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331ci 86GT - Just for fun. by fishsticks
Started on: 05-04-2021 09:51 AM
Replies: 42 (596 views)
Last post by: Raydar on 05-14-2021 11:15 PM
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Report this Post05-04-2021 09:51 AM Click Here to See the Profile for fishsticksSend a Private Message to fishsticksEdit/Delete MessageReply w/QuoteDirect Link to This Post
**WARNING - I write novella length posts**

Hey all,

I think I was on this forum 20 years or so ago, or I at least lurked here. Thought I'd pop in and show what I've been working on for the past year or so.

A little background:
This is my 4th Fiero. I took a 15+ year break to play with F-bodies, rock crawlers, Rotrex'd Tacomas, LS trucks etc. I still have some of those, but through all those years there was still a Fiero shaped hole in me. A couple years ago I bought some property with a proper shop on it, and it didn't take me long to start looking after that. My lovely bride-to-be is more than just patient with my hobbies, she encourages them. All systems were go.

I, like many others, was thinking about a 3800 swap car. I've purchased other people's projects before, and really thought I'd want a blown up 2.8 car to start fresh with. Also, I like autos for trucks and drag cars, but all my Fieros were sticks, and this one was going to be the same. This wasn't going to be a resto and it wasn't going to be a drag car. I wanted a weekend warrior that might do an occasional club day at the track.

I spent a few months looking around. I found:

- a bunch of autos
- a bunch of horrible fiberglass mods
- soooo many cars without titles
- clean stock cars that guys were still in love with and wanted way too much for
- a couple V8 swaps (4.9s)

Eventually, I ended up with this:



I actually skipped over this car twice while looking. It was listed as a "V8 Fiero with bad motor" and the pictures kind of sucked. I messaged the guy and got additional (better) pics, discovered he'd painted the car recently and it was mostly complete with a good trunk and a TITLE. I drove 3.5 hours to go look at it and bought it. The guy actually had a lot of other cool cars (not junk) at his shop. The Fiero "needs a new owner" though. He'd done some work but was over it.

The car BARELY ran and the ring gear on the flywheel was toast. We half drove, have ran the starter half pushed it onto the trailer.

I also bought one of these.



The car is an early 86GT with a 4 speed. Don't let the 88 wheels fool you. The swap was done with an Archie plate but most everything else looks like it was homebrew. The guy I bought it from did not do the swap (I actually bumped into the original owner on Youtube recently).

The original plan was simple:
- Toss the SBC
- Buy a 4.8L LS truck flywheel. They are thick enough to bridge the .400 gap between SBC and LS crank setback.
- Install LS4 to Archie plate with starter mounted to plate.
- Buy Terminator-X
- Profit

First though, I figured I'd see what was up with this SBC. Maybe I could get it going and have a motor to sell. The PO had tried to build it and put some cheap speed parts on it, including a set of heads and a FiTech. I respected that, because back when I was last into Fieros, people thought pulling a smog 305 out of a run-down truck and putting it into a Fiero somehow made a fast car.

Pulled casting numbers off the block - Wait just a second here. 1966 327-300.

Camel hump heads weren't there, obviously. Those are junk anyway, despite what your dad said. 30-30 cams suck too. It's 2021 people.

Check the front deck pad - This block's been decked. Hmmm. OK, let's pull this thing and see what we got.



Oh. Two bent valves. Tore up rocker studs. Guide plates and self-aligning rockers. There's why it runs like crap.



.030 over flat top pistons. Block was decked on both sides. About .035 deck clearance on the piston.... and the PO put .049 head gaskets on it. Reason two why this thing sucked. It was sporting like 8.5:1 compression and .085 quench.

Spin the motor over and pull the pan.



This rotating assembly is CLEAN, the forged components are still there, and it's had work done. I measured out the bores, and checked clearance on a couple bearings. This thing is fresh!

Let's look at the heads...





These are Assault Racing SBC heads. They are Chinese Dart Pro-1 knockoffs with 200cc runners and 64cc chambers. Multiple sources have flowed them at 250cfm as cast. They're notorious for having terrible hardware on them though.

But.... they're true and the seats aren't chewed up. Nor are the guides bad.

I hadn't built an SBC in a hot minute. But golly, this was starting to look like I could have some fun with it. The PO had stuck a way-too-big Thumpr cam in it with flat tappet lifters (bleh). Maybe I can bring a little 21st century tech to this thing?

That's enough for now. I'll pick this up later.

You've made it this far. Here's one last teaser picture.

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Report this Post05-04-2021 11:08 AM Click Here to See the Profile for WillClick Here to Email WillSend a Private Message to WillEdit/Delete MessageReply w/QuoteDirect Link to This Post
So it's a 0.030 over 327? Interdasting.
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Report this Post05-04-2021 12:40 PM Click Here to See the Profile for fishsticksSend a Private Message to fishsticksEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Will:

So it's a 0.030 over 327? Interdasting.


That it is.

I doubt there will be much groundbreaking tech wise in this thread. I know the 3800 is the darling currently and a lot of guys are testing the limits of various V6/Ecotec swaps now.

I'm also aware SBC swaps get some hate in various corners of the internet. Maybe some of it is warranted.

Power is power though, we're all trying to make some.

The weight thing is meh to me, as an aluminum head/intake SBC really doesn't weigh much more than the 2.8L package and when you strip out all the extras (A/C, emissions junk) the weights get even closer. If I get really stuck on weight savings at some point, I'll just go on a diet.
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Report this Post05-04-2021 01:02 PM Click Here to See the Profile for RaydarClick Here to Email RaydarSend a Private Message to RaydarEdit/Delete MessageReply w/QuoteDirect Link to This Post
This looks interesting.
The thing that most people bag on SBCs about is the low-down torque that tends to shatter Fiero manual trannies, and perceived lack of top end.
This looks to be more of a "revver". Maybe it'll make some good power without blowing differential gears all over the ground.
(I can't talk. I've got a manual 4.9, so I get it. Haven't broken any transaxles, yet, but have broken a motor mount off of the block. )

------------------
Raydar
88 Formula IMSA Fastback. 4.9, NVG T550

Praise the Lowered!

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Report this Post05-04-2021 01:33 PM Click Here to See the Profile for fishsticksSend a Private Message to fishsticksEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Raydar:

This looks interesting.
The thing that most people bag on SBCs about is the low-down torque that tends to shatter Fiero manual trannies, and perceived lack of top end.
This looks to be more of a "revver". Maybe it'll make some good power without blowing differential gears all over the ground.
(I can't talk. I've got a manual 4.9, so I get it. Haven't broken any transaxles, yet, but have broken a motor mount off of the block. )



My understanding is Archie's flywheel is also pretty heavy (>30lbs) which doesn't help with shock loading. I am using a redrilled early Corvette flywheel that weighs in at around 15lbs.

I considered overcamming the motor to shift the power curve even further up, but ultimately didn't.

Spoiler: The car actually works well. I've been driving it for several months. I am pretty easy on launches though. I don't foresee any 1.5sec 60fts in this thing's future.
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Report this Post05-04-2021 04:32 PM Click Here to See the Profile for fishsticksSend a Private Message to fishsticksEdit/Delete MessageReply w/QuoteDirect Link to This Post
So, I guess we're building a 327 now. Cool.

327s are famous for liking to wind out (though really, any SBC will). That's desirable for a small sporty car.

They also came factory with solid lifter cams. That might be cool for a retro thing and would definitely give us RPMs. But accessing the forward valve cover requires one to tip the cradle down in back. Not exactly conducive to adjusting valve lash regularly. OK, hydraulic it is.

But flat tappet hydraulics all have lazy ramps and low lift. These heads flow best around .550 valve lift. Here is the cam that came in the car.



12-601-4 Comp Cams Mutha Thumpr Hyd Flat Tappet Cam
235/249 @ .050 .489/.476 107 LSA

Good grief. This thing is designed to do one thing - idle poorly.

So, Engine Analyzer Pro is a neat program. The calculated power results aren't a substitute for real dyno time. But they usually get close if you give the program the correct values (including accounting for an actual exhaust). More importantly, the plotted curves let you compare how different components will react in a motor. For SBCs, head flow numbers, cam and intake profiles are prolific and included with the program.

Here is a plot of the two cams I narrowed my choice down to.



Blue/Green is the Comp Cams XE503 Hyd Roller 224/230 .503/.510 112LSA
Red/Cyan is the Lunati Voodoo 20120711 Hyd Roller 219/227 .515/.530 112LSA

Both are run on 1.6 rockers in this simulation. We get a touch more valve lift and the valves stay in the higher lifts (where our heads breathe the best) a bit longer.

I had great luck with the XE503 in an LT1 F-Body I had (bolt ons, cleaned up stock heads). That car dynod 363rwhp at around 6000rpm. So it was on my short list from the get go.

The Voodoo is the cam I actually ended up going with for this motor, even though the 503 made more peak HP. The Voodoo beats it all the way until around 5500RPM. While I shift this car at 6500, I don't live above 5500 for long periods of time.

So anyway, I stripped the heads and put new valves and hardware into them. Then started putting the motor back together. I used a .015 steel shim head gasket to get quench to .050. SCR came out to 9.66:1, DCR is 7.90:1.

[Cue video montage of engine assembly, cut with dramatic music and overlays of tigers roaring]





Ignore the goofy T-bars. They were floating around the shop.



That exhaust system is a war crime, but I was anxious to get the car back together so it stayed for the moment.

On Nov 24th, 2019 I drug this car home. On Jan 8th it fired for the first time. By Jan 14th I had it running pretty well.

https://youtu.be/gxey9jTzsFc
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Report this Post05-04-2021 05:46 PM Click Here to See the Profile for WillClick Here to Email WillSend a Private Message to WillEdit/Delete MessageReply w/QuoteDirect Link to This Post
Still working with the tilted carb...
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Report this Post05-04-2021 05:57 PM Click Here to See the Profile for fishsticksSend a Private Message to fishsticksEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Will:

Still working with the tilted carb...


That's a FiTech "600hp" EFI setup in ugly carb gold. I even stuck a triangle of death on it for awhile.




It's gone now.
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Report this Post05-04-2021 06:36 PM Click Here to See the Profile for fishsticksSend a Private Message to fishsticksEdit/Delete MessageReply w/QuoteDirect Link to This Post
Here's a random picture of the old clutch.



It has a Spec Stage 3+ now. The flywheel is from an early Corvette (15lb) redrilled for a Fiero clutch. It was in good shape beside the ring gear, so I bought a new ring gear. Weed burners are good for heating up ring gears for easy removal/installation. The Powermax starter needed a new clutch/drive assembly as well. Apparently I wasn't feeling like a photographer that day.

I started working on some interior things. Because OF COURSE the heater core leaked (it wasn't hooked up when I got the car). Also, someone who had no business touching electrical had touched electrical. So I had to fix that.





Dew wipes? Yeah, those too.


Found this in the CD player.


Dash wasn't terrible, but had a couple questionable spots. Vinyl wrap does a pretty good job with that.


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Report this Post05-04-2021 06:57 PM Click Here to See the Profile for fishsticksSend a Private Message to fishsticksEdit/Delete MessageReply w/QuoteDirect Link to This Post
FIero brakes suck.

88 calipers and redrilled Lambda rotors suck less. Hubs and brackets from Brian Sanburn.



A-body spindles and hubs also suck less.




You can build custom axles out of certain A-Body donors, but honestly, S-10 outers are where it's at.



13" rotors are a little big for Vette rear brackets/calipers on A-Body spindles... but close. I'll probably fab new brackets up to get them to fit. 12" rotors work for now.


New bolt pattern in the rear now. Guess I need wheels.


Enkei EKM3 18x8 5x114.3, Hankook Ventus V12 245/40/18 tires (rear)
Enkei EKM3 17x7 5x100, Hankook Ventus V12 215/45/17 tires (front)

The 88 wheels found a good home on a local 88 resto project.

This is starting to look pretty or something. Might as well get some new tail light lenses.

[This message has been edited by fishsticks (edited 05-04-2021).]

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Report this Post05-05-2021 02:03 AM Click Here to See the Profile for fishsticksSend a Private Message to fishsticksEdit/Delete MessageReply w/QuoteDirect Link to This Post
So, let's talk about this guy.



This is a VS Racing 78/75 that I bought a few years back to turbo my 6.2 LS truck with. That project just sorta never happened.

So, hey! Let's take a turbo I bought for a 5000lb truck with a liter more motor and put it on a 2700lb car! Great idea right? Right.

Well, I haven't actually done that yet.

See, the FiTech that came on the car can't read into boost, can't control timing, and it's VE table is 3 cells wide by 3 cells deep. Not exactly the pinnacle of tuning ability...

Here's where the irony sets in. One of the reasons I used to convince myself building the SBC was a neat idea was that I wouldn't be spending an extra $1000 on a Terminator-X.

So I spent $1800 on a Super Sniper and Hyperspark setup instead.



This thing reads 2.5bar, has timing control, VE tables, fueling curves, IAT and CTS offsets, extra I/O, nitrous control and the same software as the Terminator. Cool.

Why not go multi-port? Well, I'm running out of room.

See, I'd like to keep the trunk, so the turbo will need to mount over the transmission. That leaves precisely zero room for an A2A or A2W cooler. I don't want to run meth injection. BUUUUUT blow through carb fuel atomization has been shown to be a VERY effective air charge cooler. The same effect applies to a throttle body injection system.

So started putting that on... Also, those chrome valve covers? Leaked. Even with new gaskets. Red aluminum covers look cooler anyway.



The turbo project was supposed to ramp up last winter, but work took off in a big way and I found myself with exactly zero free time. And honestly, I'm pretty happy with the car as it sits.

BUT. I did do something with that horrible, booger welded, overly bendy 2" exhaust.

I cut it off and booger welded my own exhaust on. With 2.5" mandrel bends and stainless pipe. It's true dual, mostly because it was simpler and there was no room for an X pipe.




Also replaced the leaking (surprise) Sanderson headers with coated Patriots.


Pipe alignment or Fiero Takeyari?



Yeah, I know. "But you'll need to redo it again when you turbo!" Oh well. It cleaned up the exhaust note quite a bit, and it's actually quieter in the car now. Mandrel bend kits are cheap on Amazon.

https://youtu.be/HCbLI6z0w_A

This is what the engine bay looks like these days. I did loom up those couple wires that are showing.




We're basically up to date now. I've been driving it since it's been nice out. It's very well mannered. The broad torque curve lets you cruise around without shifting much, but it freight trains all the way to 6500 without missing a beat. On the freeway, 80-120 happens VERY quickly without shifting out of 4th.

Well, it did at least. Last week just cruising about 2 miles from home, the motor started to load up a bit. I got it home without much drama, but it stalled the moment I pulled it into the shop. When I started it the next day it was pig rich and running super rough. I poked around thinking maybe the FPR was stuck. Turns out I broke the #8 exhaust valve spring.

The guy on the phone at Lunati assured me those springs were good to .600 lift and 6500rpm all day long. Maury Povich has determined that to be a lie. At least it held onto the valve.

I have a set of new PAC1218 beehive springs sitting in the box here. I ordered the retainers I need, which show up tomorrow. Maybe I'll be able to get away from work and get those on.

I'll try to get some driving vids or something so there's something in here other than my endless typing...
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Report this Post05-05-2021 04:47 AM Click Here to See the Profile for Shho13Click Here to Email Shho13Send a Private Message to Shho13Edit/Delete MessageReply w/QuoteDirect Link to This Post
This is such a badass thread!!! Way cool dude, nice work, she's lookin' great!!!

------------------
"Discord"
Red 1988 GT under restoration!

Let's Go Mets!

( ͡° ͜ʖ ͡°)

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Report this Post05-05-2021 04:26 PM Click Here to See the Profile for mafv8Click Here to Email mafv8Send a Private Message to mafv8Edit/Delete MessageReply w/QuoteDirect Link to This Post
Good build, nice to see an SBC build, keep the updates coming.

------------------
84SE, aero body, 4 speed and an injected 355 V8

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Report this Post05-05-2021 09:45 PM Click Here to See the Profile for fishsticksSend a Private Message to fishsticksEdit/Delete MessageReply w/QuoteDirect Link to This Post
Well, it looks like I may have some bigger problems. I've got coolant in places I shouldn't.

Don't feel like dinking with it in the car so I'll pull it this weekend. Need to clean the shop first. At least then I can pull both heads and use my real spring tool.

I'll take pictures.
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Report this Post05-05-2021 09:47 PM Click Here to See the Profile for La fieraSend a Private Message to La fieraEdit/Delete MessageReply w/QuoteDirect Link to This Post
Nice job mate!! Looking forward to the results!!
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Report this Post05-06-2021 10:47 AM Click Here to See the Profile for WillClick Here to Email WillSend a Private Message to WillEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by fishsticks:

Well, it looks like I may have some bigger problems. I've got coolant in places I shouldn't.

Don't feel like dinking with it in the car so I'll pull it this weekend. Need to clean the shop first. At least then I can pull both heads and use my real spring tool.

I'll take pictures.


That sucks... looks like a head gasket?
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Report this Post05-06-2021 08:11 PM Click Here to See the Profile for fishsticksSend a Private Message to fishsticksEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Will:


That sucks... looks like a head gasket?


Yeah. Pulled the plugs to start moving each piston to TDC. Had the key on which ran the waterpump. Started getting a small dribble from one spark plug hole.

Couldn't find any ARP studs in stock when I put the heads on in 2019, so I bought China studs. I think they stretched. Should have just put stock bolts in, lol.


So the damper was the only thing keeping that valve and piston from an unfortunate meeting...

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Report this Post05-07-2021 07:44 AM Click Here to See the Profile for La fieraSend a Private Message to La fieraEdit/Delete MessageReply w/QuoteDirect Link to This Post
That's a bummer!! Did you put silicon seal on the head bolt threads?
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Report this Post05-07-2021 09:01 AM Click Here to See the Profile for WillClick Here to Email WillSend a Private Message to WillEdit/Delete MessageReply w/QuoteDirect Link to This Post
Chinese valvespring too?
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Report this Post05-07-2021 03:15 PM Click Here to See the Profile for fishsticksSend a Private Message to fishsticksEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Will:

Chinese valvespring too?


Right? Lunati springs. Maybe they relabel General Tso's valve springs.


For anyone else wondering WTF I was talking about when I mentioned weed burners and flywheels, this is how you pull a ring gear. MAP and Oxy torches work too. But you'll be there all day trying to use a small propane torch.

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Report this Post05-07-2021 03:16 PM Click Here to See the Profile for fishsticksSend a Private Message to fishsticksEdit/Delete MessageReply w/QuoteDirect Link to This Post

fishsticks

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quote
Originally posted by La fiera:

That's a bummer!! Did you put silicon seal on the head bolt threads?


Yeah, all wet threads got sealer. The motor held for a year. We'll see what I find when the heads come off.
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Report this Post05-07-2021 08:12 PM Click Here to See the Profile for fieroguruSend a Private Message to fieroguruEdit/Delete MessageReply w/QuoteDirect Link to This Post
Looks like a fun SBC swap.
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Report this Post05-08-2021 02:09 PM Click Here to See the Profile for fishsticksSend a Private Message to fishsticksEdit/Delete MessageReply w/QuoteDirect Link to This Post
ALL RIGHT LETS BREAK SOME STUFF!

I took the afternoon off and decided to start taking stuff apart yesterday. Only had an hour and a half to spend on it, but got some answers.

First things first... Do you hate coolant messes? I do. So we need to get the coolant out of this thing. Draining the coolant sucks. You know what works awesome though?



Ye Olde Home Depot 6hp shop vac will happily empty your cooling system for you. Just put it to the fill port and let er rip. After a minute or so, go up front and crack the radiator cap. No mess!






I'm sure many here know this already, but it's always worth saying: Plan your wire and hose routing ahead of time! Smartly laid out routing makes the difference in being able to take things apart in 15 minutes or 2 hours.

EFI Off:



Intake manifold Off:



We can see #8 intake is carboned up from reversion since the exhaust valve wasn't closing.



We'll just leave those down there for now.



Head stud nuts off. Let's make sure we're dry inside.



Hmm, no obvious signs of gasket failure from this side. #8 doesn't look great though.



Let's look closer...

Aaaaaaaaand...

Oof.




I guess this is going to turn into a REBUILD thread now.


I made a couple calls and have a few options in front of me:

  1. Send the block to a machine shop. Have them check it and install a sleeve into #8. In the interest of thoroughness, I'd likely have them go through the rotating assembly as well. I'd also take this opportunity to bump compression with different pistons.
  2. I have a buddy who's a truck mechanic. He has a professionally rebuilt L31 4 bolt main long block that's sitting in plastic. He bought it for a customer and the sale fell through. He paid too much for it though ($2400), and I don't want to kick his butt on price. Plus I only need a shortblock.
  3. Buy a forged 383 ATK shortblock from Jegs, or similar. ($2500ish)
  4. We have a 2008 Denali with a 6.2L L92. These motors have rec port heads, 403hp factory and are a cam swap away from 500hp (My 2011 6.2L truck has a few goodies and moves for a 5000lb pig). It's got 330K miles, but runs great. The trans is sketchy though, and we've considered replacing it with a new car. Yanking the trans out of that was supposed to be my next project.


LS swapping is tempting, and there's big power available, but at this point it means discarding a lot of what I've already done and starting over. I kinda want to drive this car again soon. Plus I'd need to freshen the engine.

Buying another shortblock is a quick option to get the car running again, but requires I machine a late gen1 flywheel to accept the Fiero clutch. I'd also gain some displacement and compression (with the 383). The downside of course is cost.

If I can get a quick turnaround from the machine shop, I can get this block back in service with a little more compression as well. The problem here is this block is 55 years old, and I can't figure out what caused the cylinder crack other than metal fatigue. I'm concerned this one has just lived its life.


Guess I have some thinking to do.
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Report this Post05-08-2021 09:46 PM Click Here to See the Profile for RaydarClick Here to Email RaydarSend a Private Message to RaydarEdit/Delete MessageReply w/QuoteDirect Link to This Post
I'll just drop this here. Not that it's practical, but it may give you some ideas.
https://www.fiero.nl/forum/Forum2/HTML/144310.html

When I posted this, lots of people brought up very valid points regarding SBC vs LS swaps (among other things.)
I won't attempt to argue with those, but since you're about hip-deep in SBC hardware, and not averse to "flying in the face of convention", I'll go ahead and post it anyway.

[This message has been edited by Raydar (edited 05-08-2021).]

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Report this Post05-08-2021 11:53 PM Click Here to See the Profile for fishsticksSend a Private Message to fishsticksEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Raydar:

I'll just drop this here. Not that it's practical, but it may give you some ideas.
https://www.fiero.nl/forum/Forum2/HTML/144310.html

When I posted this, lots of people brought up very valid points regarding SBC vs LS swaps (among other things.)
I won't attempt to argue with those, but since you're about hip-deep in SBC hardware, and not averse to "flying in the face of convention", I'll go ahead and post it anyway.



I like the thinking in that thread. I'm a former 4th gen F-body guy, so I've built a couple LT1s and thought in the past about doing an aluminum head swap L99. If I wasn't knee deep in nearly new SBC parts (like you mentioned) it might be a fun change of course.

One of the traps I see a lot of people fall into (especially in the "what-if" scenarios) is sky-high RPM. Yes, you can do it. Yes, valvetrain stability is a challenge that can be managed. The thing a lot of people forget is the use case though - does anyone really want to wind a motor to 8K+ on the street? I don't. I think 7K is the upper limit for a V8 street car personally, and probably less. I was pretty happy shifting at 6500 on the 327, and I wish I'd have had time to get to the dyno and compare results to what the simulations I ran said.

The nice thing about this car relates to the "Just for fun" tag I put in the title. I's not a drag car and it's not an AutoX or road race car. It's just a toy. If I was building a car for any competitive motorsport, I'd want to compete. IMO the Fiero just isn't suited to... well any of those. I'm not 19 anymore, so I'm certainly not daily driving a Fiero and dealing with all the compromises of reliability. I just built a car that I can jump in when I want to, have fun driving and hurt feelings on the interstate with.

I've had a BIG problem with scope creep on some past projects. So for this one I'm highly focused - on not making the car specialized for anything in particular.

The way I'm leaning right now is to buy a forged 383 shortblock at around 11:1 compression, bolt my current heads on, and overcam it to soften the low RPM torque. It should make gobs of power under 7000 even with the "wrong" cam, and the bottom end will stand up to being bottle fed should I get a wild hair. It's not the cheapest option, but it would me driving the car again reasonably quickly. Or maybe I'll cheap out and grab a junkyard 9:1 Vortec and do the same.

Someone please tell me why this is a bad idea.
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Report this Post05-09-2021 09:42 AM Click Here to See the Profile for fieroguruSend a Private Message to fieroguruEdit/Delete MessageReply w/QuoteDirect Link to This Post
With all you needing is a short block, the quickest path to more fun is getting another short block of the same vintage to maximize the usage of your current parts. Going with a 86+ block or going down the stroker route just means you will have more parts to buy and some parts become more complicated (stroker balancing issue). Nothing that can't be solved, but solving them will cost more $$ or require other custom parts.

Once you start looking beyond a simple short block swap that includes changing a lot of parts, then you might want to take a step back and really consider your options.

I defected from the SBC camp back in 2009 and focused my efforts and $$$ on the LS4/F40 swap when I was faced with replacing the SBC in my Fiero (pulled it to fix my DD truck). I totaled up the $$$ I was planning to spend to upgrade my SBC swap and factored in the $$$ I could get from selling off my SBC parts (got 75 cents on the dollar) and got within striking distance between the cost of the two. The main issue was the time... as there was no starter, flywheel or clutch solution at that time and it took me 3 years to get the car back on the road.

I am very happy I made the switch, but it definitely isn't for everyone.
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Report this Post05-09-2021 09:55 AM Click Here to See the Profile for La fieraSend a Private Message to La fieraEdit/Delete MessageReply w/QuoteDirect Link to This Post
Get the junkyard motor half fill it with Hard Block then get the stroker kit .060 over. Block doesnt need cooling, the heads do.
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Report this Post05-09-2021 12:19 PM Click Here to See the Profile for fishsticksSend a Private Message to fishsticksEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by fieroguru:

With all you needing is a short block, the quickest path to more fun is getting another short block of the same vintage to maximize the usage of your current parts. Going with a 86+ block or going down the stroker route just means you will have more parts to buy and some parts become more complicated (stroker balancing issue). Nothing that can't be solved, but solving them will cost more $$ or require other custom parts.

Once you start looking beyond a simple short block swap that includes changing a lot of parts, then you might want to take a step back and really consider your options.

I defected from the SBC camp back in 2009 and focused my efforts and $$$ on the LS4/F40 swap when I was faced with replacing the SBC in my Fiero (pulled it to fix my DD truck). I totaled up the $$$ I was planning to spend to upgrade my SBC swap and factored in the $$$ I could get from selling off my SBC parts (got 75 cents on the dollar) and got within striking distance between the cost of the two. The main issue was the time... as there was no starter, flywheel or clutch solution at that time and it took me 3 years to get the car back on the road.

I am very happy I made the switch, but it definitely isn't for everyone.


Thanks for taking the time to explain your journey. Before I bought this car, I did some lurking here to see what the current trends were. I've checked in on a lot of your threads and watched your progress. You've definitely brought some incredible engineering and products to the Fiero community. And (since I notice these things) you've been free in sharing your knowledge, rather than trying to cover it as some sort of trade secret. As a guy who struck out on his own trying to push the envelope on another platform (GMT360), I get the time investment that's required.

Obviously I'm not the first to go down the SBC Fiero path, nor will I be the last. But it's good to learn from those who've already been there.

 
quote
Originally posted by La fiera:

Get the junkyard motor half fill it with Hard Block then get the stroker kit .060 over. Block doesnt need cooling, the heads do.


You think like I do, lol. 388 FTW.


Here's where I'm at after a day or so of research:

  • Local machine shops with any sort of automotive reputation are all over 1-2 months out.
  • "Rebuilder" machine shops within 100 miles don't offer anything other than stockish parts, even on their "performance" offerings.
  • CL is filled with the usual "rebuilt/race motor but I lost the receipts" for $4000+, rusty "ran great when pulled" motors that have sat in the rain for 20 years etc.
  • Early SBC stuff is gold plated. Silly people asking $600/ea for camel hump heads, $300 for 993s etc. I have this weird feeling I could sell this cracked 327 block...
  • Junkyards want $1000ish for high mile SBCs and won't sell a shortblock.
  • TLDR: I live on the Left Coast. Everything is expensive, including LS stuff.


Also:
  • I am at the point in life where the money-time paradox has shifted from lacking money to lacking time.
  • This isn't an unlimited budget project, but I have cash to throw at it.
  • Time is at a premium right now. I own a small business and we've had our two best quarters ever back to back.
  • I have traditionally been the guy who needs the have his hands in every part of a project. But learning to be a good manager has taught me that sometimes you have to delegate.


So, I've delegated my engine build and bought this:
https://www.jegs.com/i/ATK-...es/059/SP52/10002/-1

It should be overkill for the power/RPM level I want. Not top shelf parts per se but I've had good luck with Scat in the past. My understanding is ATK builds their performance line in house (they farm out the cheaper rebuilds to Mexico) and they seem to review well.

I'm going to need:
  • A new flywheel - the OEM one I use currently is available in one-piece RMS flavor. I should be able to handle redrilling it here on the press.
  • A new oil pan - I've been wanting to try a baffled circle track pan, and I believe there's axle clearance.
  • A new cam - Would need to happen anyway. My retrofit lifters are tall and SHOULD clear the late model bores. But not a big deal if not.
  • There are a couple other "Wish I would have..."s that I will address.

[This message has been edited by fishsticks (edited 05-09-2021).]

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Report this Post05-09-2021 02:00 PM Click Here to See the Profile for La fieraSend a Private Message to La fieraEdit/Delete MessageReply w/QuoteDirect Link to This Post
Is it internally or externally balanced? The description is not clear.
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Report this Post05-09-2021 02:50 PM Click Here to See the Profile for fishsticksSend a Private Message to fishsticksEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by La fiera:

Is it internally or externally balanced? The description is not clear.


All SBC's are -technically- internally balanced. However, the post 86 blocks and roller blocks (1 piece RMS) moved the rear crank weight to the flywheel to make room for the rear main seal adapter. A lot of people consider that to now be externally balanced.

The one I bought is a later roller block, so it will be 1 piece RMS and need the weighted flywheel. If you look in the description, they refer to the block as a "Seasoned OE 4 bolt main 1pc seal 1996-2000 roller block". That means it will be an L31 block.

[This message has been edited by fishsticks (edited 05-09-2021).]

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Report this Post05-09-2021 05:53 PM Click Here to See the Profile for fieroguruSend a Private Message to fieroguruEdit/Delete MessageReply w/QuoteDirect Link to This Post
The 400 sbc, where externally balanced with weights on the crank and balancer. Early strokers that used this crank, had to keep both weights. The aftermarket has been doing some interesting balancing things, so hopefully the description is correct where all you need is the 86+ flywheel and don't need to mess with a weight on the balancer. Not much room for it with the Archie balancer.
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Report this Post05-09-2021 08:49 PM Click Here to See the Profile for La fieraSend a Private Message to La fieraEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by fishsticks:


All SBC's are -technically- internally balanced. However, the post 86 blocks and roller blocks (1 piece RMS) moved the rear crank weight to the flywheel to make room for the rear main seal adapter. A lot of people consider that to now be externally balanced.

The one I bought is a later roller block, so it will be 1 piece RMS and need the weighted flywheel. If you look in the description, they refer to the block as a "Seasoned OE 4 bolt main 1pc seal 1996-2000 roller block". That means it will be an L31 block.



Ah I see!! Get yourself an ATI Superdamper for it. You will fell the difference.
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Report this Post05-09-2021 11:14 PM Click Here to See the Profile for fishsticksSend a Private Message to fishsticksEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by fieroguru:

The 400 sbc, where externally balanced with weights on the crank and balancer. Early strokers that used this crank, had to keep both weights. The aftermarket has been doing some interesting balancing things, so hopefully the description is correct where all you need is the 86+ flywheel and don't need to mess with a weight on the balancer. Not much room for it with the Archie balancer.


Good catch. I did check Scat's catalog though and all their 3.75 stroke cranks are internally weighted on the front side.


Fun fact: The balancer on the front of my engine is a stock balancer for 67-71 Chevy inline 6 engines. I believe it's the same one Archie uses. Dayco PB1023N The timing mark just needs moved.
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Report this Post05-10-2021 11:20 AM Click Here to See the Profile for fieroguruSend a Private Message to fieroguruEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
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Originally posted by fishsticks:
Fun fact: The balancer on the front of my engine is a stock balancer for 67-71 Chevy inline 6 engines. I believe it's the same one Archie uses. Dayco PB1023N The timing mark just needs moved.


If you want to move into the serpentine belt era...
https://www.fiero.nl/forum/Forum2/HTML/118182.html
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Report this Post05-10-2021 01:56 PM Click Here to See the Profile for fishsticksSend a Private Message to fishsticksEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
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Originally posted by fieroguru:


If you want to move into the serpentine belt era...
https://www.fiero.nl/forum/Forum2/HTML/118182.html


Shhhh I don't need another project to add to the list.
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Report this Post05-11-2021 11:42 AM Click Here to See the Profile for fishsticksSend a Private Message to fishsticksEdit/Delete MessageReply w/QuoteDirect Link to This Post
Started ordering supporting parts today, starting with an oil pan:

https://www.moroso.com/chevrolet-small-block21320/

I'd rather there were a few more dimensions on that listing. But taking rough measurements with a tape shows it should clear the passenger side axle.

The capacity will be nice, but I'm really after some proper windage control and the crank scraper. It always seemed to me that windage issues would be compounded in an SBC Fiero, since oil will slosh to the passenger side (rear) of the pan during acceleration. Circle track guys deal with essentially the same issue.

Also grabbed the deep sump and a Melling 55HV.

[This message has been edited by fishsticks (edited 05-11-2021).]

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Report this Post05-11-2021 10:24 PM Click Here to See the Profile for La fieraSend a Private Message to La fieraEdit/Delete MessageReply w/QuoteDirect Link to This Post



I'm building a 383 for a customer and it will go in a 1969 C10 Chevy pick up 4 speed manual.
And I'm using a real man's cam, solid flat tappet.
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Report this Post05-11-2021 11:46 PM Click Here to See the Profile for fishsticksSend a Private Message to fishsticksEdit/Delete MessageReply w/QuoteDirect Link to This Post
Solid flat tappet for all those revs you need for a truck. Better put some triple valve springs on it too. At least it's neon green so he won't lose it.

I like how you mounted your methanol tank directly between the carb and the intake manifold on your car. Less hoses that way.
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Report this Post05-12-2021 06:18 PM Click Here to See the Profile for La fieraSend a Private Message to La fieraEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
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Originally posted by fishsticks:

Solid flat tappet for all those revs you need for a truck. Better put some triple valve springs on it too. At least it's neon green so he won't lose it.

I like how you mounted your methanol tank directly between the carb and the intake manifold on your car. Less hoses that way.



Dual springs on solid cams is old tech, there's so much advance in metalurgy today that makes dual springs obsolete. I've always used very aggressive solid profiles with single springs. The engine in my car is F.I. The big box is to constantly keep full atmospheric pressure at all RPMs at WOT.
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Report this Post05-12-2021 07:01 PM Click Here to See the Profile for fishsticksSend a Private Message to fishsticksEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
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Originally posted by La fiera:
Dual springs on solid cams is old tech, there's so much advance in metalurgy today that makes dual springs obsolete. I've always used very aggressive solid profiles with single springs. The engine in my car is F.I. The big box is to constantly keep full atmospheric pressure at all RPMs at WOT.



I am just razzing you.

I don't bother with flat tappet anything anymore, since roller ramp designs are so much better. The triple spring thing was for the old guys jumping coke cans in the back.

And I figured it was some sort of plenum on your car.

Where I come from, if we talk smack to you it means we like you.
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