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Camshaft / Rockers Combination - 3.1 Stroker by 82-T/A [At Work]
Started on: 10-05-2019 08:25 AM
Replies: 25 (345 views)
Last post by: lou_dias on 10-15-2019 09:21 AM
82-T/A [At Work]
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Report this Post10-05-2019 08:25 AM Click Here to See the Profile for 82-T/A [At Work]Send a Private Message to 82-T/A [At Work]Edit/Delete MessageReply w/QuoteDirect Link to This Post

Guys, second tech post of the day, I'm on a roll. Disclaimer... my Fiero has been in storage for a decade, and it'll probably stay in storage for another decade. But I want to buy a bunch of parts while I can still get them and I'm on a kick right now to collect parts. Today I have a question about cam / rocker combo.

The engine is my Fiero's original 2.8 V6/60 that I had the 3.1 "Stroker Kit" from ARI Engines installed in it. When I had the engine put together by a machine shop, I had the "Fireball" cam, whatever crap that was. I "thought" I did the break-in properly... but after a few months of driving it off and on, it wiped out a cam-lobe. So... no idea. I intend to go back through the motor again, even though it has less than 2k miles on it since the rebuild. But I wanted to know if my cam and rocker selection was acceptable.

I have a Crane Cams H272 Cam and I've got the Crane 1.52:1 roller rockers installed.

I'm going to be using the factory intake and the factory throttle body. The intake has been port-matched and hogged out, and the throttle body was ported back in the day by Darrel Morse.

Again, it's a 3.1 crank and rods with a .040 overbore piston set. I remember that previously... the engine would "fall flat" around 4,500 rpms... and just didn't produce ANY power at all beyond that. It got worse as time went on to the point where it really didn't produce much power above 4,000 rpms.

I know that even as a 3.1... air is getting restricted, and I'm committed to keeping the factory intake and plenum. Question though is... will the H272 and 1.52:1 be a good combination to give me the most about of power that I'm going to be able to get out of the car?

(side note, I have 1.7lb Accel pintle-style injectors.)


Thank you!!!

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olejoedad
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Report this Post10-05-2019 08:46 AM Click Here to See the Profile for olejoedadClick Here to Email olejoedadSend a Private Message to olejoedadEdit/Delete MessageReply w/QuoteDirect Link to This Post

Have you seen the lower intake mod that removes material from the wall between the paired intake runners?
It is not visible and is claimed to raise the usable powerband.

I think lou dias posted the information.

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82-T/A [At Work]
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Report this Post10-05-2019 09:34 AM Click Here to See the Profile for 82-T/A [At Work]Send a Private Message to 82-T/A [At Work]Edit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by olejoedad:

Have you seen the lower intake mod that removes material from the wall between the paired intake runners?
It is not visible and is claimed to raise the usable powerband.

I think lou dias posted the information.



No! I haven't seen that! I'll take a look!

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Report this Post10-05-2019 09:49 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

When you installed the 272, did you have any head work done, to accommodate the springs? The 272 has .454/.480 lift, at the valve, using the stock ratio 1.52 rockets. Stock springs will coil bind. My aftermarket springs would coil bind.
With all of that said, it seems like a lot of Crane cams wiped lobes, back in the day.

[This message has been edited by Raydar (edited 10-05-2019).]

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Notorio
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Report this Post10-06-2019 12:28 AM Click Here to See the Profile for NotorioSend a Private Message to NotorioEdit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by 82-T/A [At Work]:
No! I haven't seen that! I'll take a look!


Lou kindly sent me this link recently to his YouTube post: https://www.youtube.com/watch?v=oCr39y4nHoQ

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82-T/A [At Work]
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Report this Post10-06-2019 01:54 AM Click Here to See the Profile for 82-T/A [At Work]Send a Private Message to 82-T/A [At Work]Edit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by Raydar:

When you installed the 272, did you have any head work done, to accommodate the springs? The 272 has .454/.480 lift, at the valve, using the stock ratio 1.52 rockets. Stock springs will coil bind. My aftermarket springs would coil bind.
With all of that said, it seems like a lot of Crane cams wiped lobes, back in the day.



Hey Raydar!!! Good to see you're still around!!! I haven't been in the Tech forums for a long time.

So, I've never actually installed the H272. My question on the H272 w/ 1.52:1 roller rockers was whether or not that would be a good option. The cam that was installed in my engine when it was rebuilt was actually some cam called the "Fireball" cam that ARI offered. That one got wiped out, and I don't so much care for it anyway.

My goal is to have the H272 cam installed, with the 1.52:1 rockers. But on that topic... I'm pretty sure nothing was re-used in the top-end... but I really can't be sure. It was so long ago, and I was living in an apartment and... quite frankly... shouldn't have been buying that stuff anyway. What would you recommend I buy for the top-end? (springs / clips / retainers) with my H272 Cam? The cam is oiled up, and sitting in a box in a storage unit in South Florida.

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RayOtton
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Report this Post10-06-2019 09:34 AM Click Here to See the Profile for RayOttonClick Here to Email RayOttonSend a Private Message to RayOttonEdit/Delete MessageReply w/QuoteDirect Link to This Post

FWIW, I did every single one of the airflow mods including bored out exhaust logs, "Dawg style" upper intake, bored throttle body, low restriction cat and cleaned up Y-pipe. Also put in a Hypertech chip and underdrive pulleys.

All them them made small differences according to the butt dyno.

Then I did the 1.6 rockers and the engine just "woke up".

Not so much off the line but from 3000 RPM up to 5500 RPM there is a huge difference. Before the rockers there wasn't any reason to go past 4500 RPM, after the rockers it pulls even at 6000 RPM's though generally I don't go above 5500.

I'm so happy with the results I've given up any thought of a swap.

[This message has been edited by RayOtton (edited 10-06-2019).]

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La fiera
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Report this Post10-06-2019 02:23 PM Click Here to See the Profile for La fieraSend a Private Message to La fieraEdit/Delete MessageReply w/QuoteDirect Link to This Post

What a lot of people dont know is that when 1.6 rockers are installed the camshaft's profile changes proportionally.
In other words, your valves open earlier, stay open longer and close later in comparison to the stock rocker ratio so the cam seems "bigger".
The only concern is what Raydar mentioned about coil bind.
As far as the cam lobes being wiped out that is contributed by low quality oil with not enough zinc and phosphorous for break-in and regular service.

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Report this Post10-06-2019 11:50 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

 
quote
Originally posted by 82-T/A [At Work]:


Hey Raydar!!! Good to see you're still around!!! I haven't been in the Tech forums for a long time.

So, I've never actually installed the H272. My question on the H272 w/ 1.52:1 roller rockers was whether or not that would be a good option.


1.52 is, technically, the stock ratio. Aftermarket vendors will typically be a bit more "exacting" than the factory. (1.52 vs "sorta" 1.5.)
Yeah... The 272 is probably my favorite V6-60 cam. (I *always* prefer stock ratio rockers. They're what the cam is designed to run with.)
It's what I had in my 3.4. I used the Comp Cams roller tip rockers. Didn't see any point in springing for the full roller rockers. Seemed like a bunch of trouble and money, for very little gain.
But yeah... you'll have to have the spring pockets machined to accommodate the compressed height of the spring. Other than that, and breaking the cam in, properly, I can't really offer anything.

Good to see you man!

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lou_dias
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Report this Post10-07-2019 09:29 AM Click Here to See the Profile for lou_diasClick Here to Email lou_diasSend a Private Message to lou_diasEdit/Delete MessageReply w/QuoteDirect Link to This Post

Keep in mind that a 3.1 with a traditionally fully ported intake should be fine for a 3.1 ... My 3.4 is 10:1 compression with a 480/480 roller cam and the dyno is lower in the video because my racing wheels weigh 52 lbs each...
When I was using 45lbs wheels my torque was up to 249 ft*lbs years before I got into serious intake mods...

[This message has been edited by lou_dias (edited 10-07-2019).]

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82-T/A [At Work]
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Report this Post10-09-2019 05:56 AM Click Here to See the Profile for 82-T/A [At Work]Send a Private Message to 82-T/A [At Work]Edit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by La fiera:

What a lot of people dont know is that when 1.6 rockers are installed the camshaft's profile changes proportionally.
In other words, your valves open earlier, stay open longer and close later in comparison to the stock rocker ratio so the cam seems "bigger".
The only concern is what Raydar mentioned about coil bind.
As far as the cam lobes being wiped out that is contributed by low quality oil with not enough zinc and phosphorous for break-in and regular service.


I'll be the first to admit, I bought a cheap cam at the time. The "Fireball 2" cam... don't remember who made it. But I used Shell Rotella which even advertised having more Zinc on it. But I changed it out after 500 miles and immediately went to synthetic. Maybe that was my problem. I don't know. Next time, I'm going to have to do it right... it's going to be a few years.


 
quote
Originally posted by Raydar:

1.52 is, technically, the stock ratio. Aftermarket vendors will typically be a bit more "exacting" than the factory. (1.52 vs "sorta" 1.5.)
Yeah... The 272 is probably my favorite V6-60 cam. (I *always* prefer stock ratio rockers. They're what the cam is designed to run with.)
It's what I had in my 3.4. I used the Comp Cams roller tip rockers. Didn't see any point in springing for the full roller rockers. Seemed like a bunch of trouble and money, for very little gain.
But yeah... you'll have to have the spring pockets machined to accommodate the compressed height of the spring. Other than that, and breaking the cam in, properly, I can't really offer anything.

Good to see you man!


Thanks Raydar, having this conversation, I can almost remember the machine shop asking me if they wanted me to re-use the old springs. What they did was install big washers (of sorts) under the springs to give them better spring rates, or something... they knew what they were doing, but I was obviously re-using my old springs.

I did buy the H272 cam a while back, and that's what I'll be using, and I have the 1.52:1 rockers (thanks for that info). I think what I'll do is replace everything else (valves are new). So should I just go ahead and order all new parts from Crane Cams? Do you happen to know what I should be looking for when I order from JEGS or SUMMIT? Thanks!!!


 
quote
Originally posted by lou_dias:

Keep in mind that a 3.1 with a traditionally fully ported intake should be fine for a 3.1 ... My 3.4 is 10:1 compression with a 480/480 roller cam and the dyno is lower in the video because my racing wheels weigh 52 lbs each...




Damn, 10:1 is pretty nice. Yeah... I port-matched, and hogged out. This time, I'll probably do the entire extrude-hone process on all the intake pieces... just want to make everything perfect.

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La fiera
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Report this Post10-10-2019 09:18 AM Click Here to See the Profile for La fieraSend a Private Message to La fieraEdit/Delete MessageReply w/QuoteDirect Link to This Post

Synthetic means nothing is if doesnt have the right additive package for flat tappet cams.
This are the oils I recommend for our engines because they are rich in zinc and phosphorous and some of these oils have some Molybdenum.

Valvoline VR series Non-Synthetic
Liqui Moly MoS2 10W-40 Semi-Synthetic
Lucas Hot Rod series Non-Synthetic
Maxima Triple-Ester series Full-Synthetic

They are available in any viscosity you use except the Liqui-Moly MoS2 only is availabe in 10W-40 grade.

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Report this Post10-10-2019 10:00 AM Click Here to See the Profile for lou_diasClick Here to Email lou_diasSend a Private Message to lou_diasEdit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by 82-T/A [At Work]:
I'll probably do the entire extrude-hone process on all the intake pieces... just want to make everything perfect.


/drool

Where will you get that done at and how much?

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Report this Post10-10-2019 11:59 AM 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 lou_dias:


/drool

Where will you get that done at and how much?


It'll be cheaper if he makes a sheet metal intake and gain more performance
that process is expensive. I checked 6 years ago and they wanted $1200 for the upper and lower plenum.

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Report this Post10-10-2019 01:38 PM Click Here to See the Profile for lou_diasClick Here to Email lou_diasSend a Private Message to lou_diasEdit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by La fiera:
It'll be cheaper if he makes a sheet metal intake and gain more performance
that process is expensive. I checked 6 years ago and they wanted $1200 for the upper and lower plenum.

Lower or did you mean the middle?

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82-T/A [At Work]
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Report this Post10-10-2019 11:12 PM Click Here to See the Profile for 82-T/A [At Work]Send a Private Message to 82-T/A [At Work]Edit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by La fiera:

Synthetic means nothing is if doesnt have the right additive package for flat tappet cams.
This are the oils I recommend for our engines because they are rich in zinc and phosphorous and some of these oils have some Molybdenum.

Valvoline VR series Non-Synthetic
Liqui Moly MoS2 10W-40 Semi-Synthetic
Lucas Hot Rod series Non-Synthetic
Maxima Triple-Ester series Full-Synthetic

They are available in any viscosity you use except the Liqui-Moly MoS2 only is availabe in 10W-40 grade.



Hey, thanks for this. I really appreciate this. I'm going to write all this down. What specific oil would you recommend FOR break-in, specifically?


 
quote
Originally posted by lou_dias:

/drool

Where will you get that done at and how much?


I've never had it done, but the company is named "Extrude Hone" after the service they provide:
https://extrudehone.com/ind...solutions/automotive

Years ago, they almost exclusively did automotive... primarily hogging out intake manifolds. But it seems they've grown substantially, and their website is so convoluted that I'm not even sure what it is they offer anymore. I'd guess that maybe they're now in the business of providing the technology, rather than the service? I can't be sure. I think I'm going to shoot them an e-mail....

Essentially what they do is... there is a vat of metallic "goo..." This goo is forced through the intake at a high rate of speed. Essentially, they would build a jig that would attach to the neck of your intake plenum, and then a jig at the base of the intake manifold. The metallic / abrasive goo would be forced at... I dunno... whatever PSI or miles an hour, and it would carve out the plenum, runners, and intake. While there would certainly be a porting / hogging effect, the primary benefit is that all restriction and imperfection is completely removed, leaving the intake with what's essentially a perfect sheen with NO obstruction whatsoever.

They had numbers on there on what people typically expected to see in gains, and while "max" horsepower was increased, the most noticeable improvement was the dyno curve from mid to upper RPMs.

I don't know anyone who has ever done this on a Fiero... but with the type of 3-piece intake system we have, it just makes sense. I'll e-mail and find out and respond back.

EDIT: Ok... yeah, so that company ONLY sells the equipment now. But, there are multiple companies online that offer the service using their purchased equipment.

Here is one in CA: https://www.extrudehoneafm....ting-in-torrance-ca/
And here is one in NY: https://boneheadperformance.com/extrude-honing/

and there are a few others...


 
quote
Originally posted by La fiera:

It'll be cheaper if he makes a sheet metal intake and gain more performance
that process is expensive. I checked 6 years ago and they wanted $1200 for the upper and lower plenum.


Yeah, it would... but I'm one of those people who wants everything to look 100% stock while gaining the most performance I can on an otherwise slightly modified engine.

[This message has been edited by 82-T/A [At Work] (edited 10-10-2019).]

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lou_dias
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Report this Post10-11-2019 10:02 AM Click Here to See the Profile for lou_diasClick Here to Email lou_diasSend a Private Message to lou_diasEdit/Delete MessageReply w/QuoteDirect Link to This Post

From the NY company they list:

6 Cylinder Aluminum EFI Intake (2 pc)- $910

Anyone can port the lower intake. The main restriction is definitely the upper and middle...

EDIT:
YIKES!
6 Cylinder Cast Iron Heads- $1145

[This message has been edited by lou_dias (edited 10-11-2019).]

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Report this Post10-11-2019 10:18 PM Click Here to See the Profile for La fieraSend a Private Message to La fieraEdit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by lou_dias:

YIKES!
6 Cylinder Cast Iron Heads- $1145



WOW!!! And that is without flow numbers!!!???

I got the heads on my 2.8 CNCed for $700 with 195 @ .500! And with these heads and the upper sheet metal intake you got from me the 2.8 made 173WHP @ 6000rpm

[This message has been edited by La fiera (edited 10-11-2019).]

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Report this Post10-12-2019 03:04 AM Click Here to See the Profile for 82-T/A [At Work]Send a Private Message to 82-T/A [At Work]Edit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by lou_dias:

From the NY company they list:

6 Cylinder Aluminum EFI Intake (2 pc)- $910

Anyone can port the lower intake. The main restriction is definitely the upper and middle...

EDIT:
YIKES!
6 Cylinder Cast Iron Heads- $1145




Ugh... I know, that is brutal.

The biggest cost is because they have to make their own jig for your engine (in most cases)... though I'd suspect enough people have done this that they probably already have what they need. I'd be interested to know how they can do the work from plenum to cyl heads without damaging the valve seats, unless they expect you to install new ones.

The biggest benefit is the port-matching and eliminating restrictions in the intake. It does "polish" the pathways, but of course the media passes through the path of least resistance... which would be where the air goes, so people shouldn't expect to see an intake where every portion of it is gleaming like a polished gemstone. The areas that really get polished and smoothed to a mirror finish are the areas where there's some type of restriction or resistance... the rest of the intake will at best look "deburred."

Still... seems awesome...

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Report this Post10-12-2019 04:56 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 82-T/A [At Work]:
Ugh... I know, that is brutal.

The biggest cost is because they have to make their own jig for your engine (in most cases)... though I'd suspect enough people have done this that they probably already have what they need. I'd be interested to know how they can do the work from plenum to cyl heads without damaging the valve seats, unless they expect you to install new ones.

The biggest benefit is the port-matching and eliminating restrictions in the intake. It does "polish" the pathways, but of course the media passes through the path of least resistance... which would be where the air goes, so people shouldn't expect to see an intake where every portion of it is gleaming like a polished gemstone. The areas that really get polished and smoothed to a mirror finish are the areas where there's some type of restriction or resistance... the rest of the intake will at best look "deburred."

Still... seems awesome...


Actually the polishing part of the process is what i don't like. Believe it or not polishing a pipe in the inside where air travels will create resistance due to turbulence
of the friction between the mirror-like surface and the air traveling on it. I know it sounds counterintuitive but that's why I'm upgrading my intake and head port to gain more CFM by removing friction.

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Report this Post10-13-2019 11:26 PM Click Here to See the Profile for 82-T/A [At Work]Send a Private Message to 82-T/A [At Work]Edit/Delete MessageReply w/QuoteDirect Link to This Post

 
quote
Originally posted by La fiera:

Actually the polishing part of the process is what i don't like. Believe it or not polishing a pipe in the inside where air travels will create resistance due to turbulence
of the friction between the mirror-like surface and the air traveling on it. I know it sounds counterintuitive but that's why I'm upgrading my intake and head port to gain more CFM by removing friction.



That never occurred to me! So what you're saying is really you just want to get rid of the restrictions (bumps, ridges, etc...), but you don't want a polished surface?

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Report this Post10-14-2019 07:45 AM Click Here to See the Profile for RayOttonClick Here to Email RayOttonSend a Private Message to RayOttonEdit/Delete MessageReply w/QuoteDirect Link to This Post

A long, long time ago I read the same thing in Hot Rod magazine.

I seem to recall something about too smooth surfaces reducing turbulence too much.

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Report this Post10-14-2019 01:29 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 82-T/A [At Work]:
That never occurred to me! So what you're saying is really you just want to get rid of the restrictions (bumps, ridges, etc...), but you don't want a polished surface?


Its on the same principle of the dimples on a golf ball. Its more important in my intake manifold
design because of the location of the injectors in relation with the track. If I would polish the track, the fuel that sticks to the walls of the manifold would not have anything to slow it down (rough surface). The fuel would just trickle down fast into the combustion chamber in liquid form. What the roughness does is slow down the fuel and gives it time to evaporate so when the valve opens it can be sucked into the combustion chamber and burn quickly. Fuel has to evaporate before it burns.


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Report this Post10-14-2019 05:48 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

 
quote
Originally posted by 82-T/A [At Work]:
I think what I'll do is replace everything else (valves are new). So should I just go ahead and order all new parts from Crane Cams? Do you happen to know what I should be looking for when I order from JEGS or SUMMIT? Thanks!!!


I wouldn't use the Crane lifters. Have heard bad things about them.
Most people seem to recommend GM lifters, although they are rather spendy. (And that was a long time ago. It's been probably 15 years since I built my engine. I hesitate to recommend anything, since things are constantly changing. Listen to "modern" advice.)
I would, OTOH, buy the springs that Crane recommends for your cam, if they are still available. You'll have to make measurements, or give all the info to the people who do your head work. (Compressed and "relaxed" spring height, etc.)
My rockers were the Comp roller tip rockers. Didn't see any point in going full roller. Lots of money for not a lot of gain. (Did I already say that?)

[This message has been edited by Raydar (edited 10-14-2019).]

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Report this Post10-14-2019 06:07 PM Click Here to See the Profile for olejoedadClick Here to Email olejoedadSend a Private Message to olejoedadEdit/Delete MessageReply w/QuoteDirect Link to This Post

One bit of advice is to buy all of the valvetrain components from one repudable manufacturer.
The advances in computer assisted design enable the manufacturers to analyze valvetrain dynamics and the associated destructive harmonics, and use that info to minimize problems.
Mixing and matching sources could lead to unhappy results, even if the components are purchased from repudable manufacturers.

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Report this Post10-15-2019 09:21 AM Click Here to See the Profile for lou_diasClick Here to Email lou_diasSend a Private Message to lou_diasEdit/Delete MessageReply w/QuoteDirect Link to This Post

roller tips don't do much but roller fulcrum does which is why the GEN2 rockers are roller fulcrum from the factory...
...but when I rebuild a motor I like new parts and that's why I went full roller...and that's why I made my valve cover spacers...

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