PFF - Pennock's Fiero Forum, PDA Edition

The Turbo 3500 F23 swap (Page 42/80)

ericjon262

JUL 29, 09:21 PM

some progress, lots of parts on order, and a short block is almost assembled.

I got the piston rings in, and on the pistons, and the pistons in their respective holes, the top rings are steel, and took way longer than the 2nd rings to gap, the second rings are a napier cut ring.

I painted the valve covers with some aluminum colored paint, hopefully the paint looks good for a longer time than the bare aluminum did.

I also came to the realization that I made a somewhat large mistake with this car fairly recently. when I pulled the intake manifold a few months ago, I noticed the plenum gasket wasn't crushed around one of the ports. I should have thought a bit harder about this and fixed it on the spot and tried running the engine again. in the past when it didn't want to play nice, it would only run if it was super rich, which makes sense if there's a huge air leak into the plenum causing 2 or 3 cylinders to be much leaner than the others, which are now crazy rich and not wanting to fire. this realization has triggered the decision to ditch my custom intake for now. I'm undecided as to whether I'll run a ported stock piece, or make a new custom manifold similar to what was there.

I also need to fix my front trans mount, I put that thing together very poorly, because I was in a rush to get the car together. I'm also going to redo my engine mount so that it bolts to a stock pan without potentially weakening it.

for now, I plan to throw the car together N/A, but try and carefully plan for adding a turbo after I can drive it again.

I started looking for a better way to incorporate the oil drain into the pan, you can see the old pan and drain below the engine in one of the pictures.

I'm thinking the best placement might actually be to go between the starter and the block, there's quite a bit of room and it gets the drain out of the way of the electrical connections on the back of the starter.

The plan would be to weld a piece of aluminum tubing to the pan, with a fitting above the starter to accept a hose. the tube would intersect the pan at approximately the same angle as my hand in the pictures.

I decided to splurge and get an MS3 Pro Ultimate and ditch the MS3x, I'm currently racking my brain trying to find the best place to mount it, I think I'm going to hack the back out of the console and mount it where the stock ECM went, but I'm still contemplating mounting it in the engine compartment near where the stock battery tray was, or the trunk.

I really wanted to run a pi dash, but I don't think I'll be able to, mainly because the Fiero dash won't fit a reasonable size display without enlarging it quite a bit, and I would rather not take on a project like that yet, so I might also pick up a microquirt and have it run the stock gauges via can bus.

one of the other goals of this teardown and rebuild, was to convert to DBW. I hated on DBW quite a bit when I started this swap years ago, but I like it more and more. especially because it opens a ton of doors for different modes of traction and launch control, I'd also bet that I could make a "valet mode" that limits throttle position.

unfortunately, I didn't realize that the MS3 Pro doesn't support DBW by itself and requires an add on controller. a guy in Finland came up with this:

https://www.dbwx2.com/

it's about $385 not including shipping.

https://shop.protoparts.fi/...rt?change_country=us

it appears to offer pretty good response. I've got a 75mm LS4 TB on the way from Fieroguru that I'll adapt to a manifold, either my custom one, or a one of the plenums I have sitting around the house. my Custom plenum needs work to be made right though, the welding shop who put it together for me warped the hell out of it, I had it machined "flat" and then none of the bolts lined up, so I'll probably ditch it and start over. another plus to DBW will be packaging. the throttle cable had to run over the top of the plenum, and the LS1 TB I have, has a huge 4" mouth on it, so it required special adapters to make the charge piping fit right.

I'm also trying to have a non-lift-off decklid again, I am both glad I cut the hinge boxes out, and with I hadn't. if I can find a new decklid that isn't butchered like mine is, I'll make a set of hinges like Fieroguru made for his car.

http://www.fiero.nl/forum/Forum1/HTML/085829.html

it'll be easier to access spark plugs, and I'll regain a functional trunk of sorts. in doing this, I will have to swap the intake manifold to point towards the transmission, but I think that will only help many of the other packaging problems I have, and make getting AC back way easier. it should also help the engine come onto boost sooner, by shortening the intake tract.

in other non engine related news, I ripped my intercooler reservoir out, I'm planning on making or buying something smaller, that will mount closer to the heat exchanger. I also plan to mount the pump all the way up there as well. I'll end up building a wood or sheet metal panel to fill the hole where the old tank went.

pmbrunelle

JUL 30, 12:02 AM

While it seems like you're trying to simplify things e.g. by skipping the turbo install, you still have a lot of work to do!

Are your ring gaps and piston-bore clearances set up for the eventual turbo install?

What sort of placement/orientation do you foresee for the turbo? On my Fiero, the oil drain fitting on the oil pan worked better on the trunk side of the engine, so I am wondering how you are going to package this with the firewall side oil drain.

ericjon262

JUL 30, 12:40 AM

quote

Originally posted by pmbrunelle:

While it seems like you're trying to simplify things e.g. by skipping the turbo install, you still have a lot of work to do!

Are your ring gaps and piston-bore clearances set up for the eventual turbo install?

What sort of placement/orientation do you foresee for the turbo? On my Fiero, the oil drain fitting on the oil pan worked better on the trunk side of the engine, so I am wondering how you are going to package this with the firewall side oil drain.

I wouldn't go as far as to say I'm skipping the turbo install, just taking a much more well planned approach, Previously, I had an idea and said "that's perfect" now I understand I need to question things on a much higher level to ensure that I accomplish the goals of having a fun, reliable, powerful car, that I can enjoy.

Planning on the turbo being over the transaxle, similar to how it was, just closer to the engin, and more well executed. the rings are from total seal, the gaps are slightly larger than their up to 15 PSI spec, and slightly smaller than their 15-30 PSI spec.

from a fluid dynamics standpoint, the oil drain on the front of the engine is better, the motion of the rotating and reciprocating assemblies can provide a sort of scavenging effect to help pull the oil from the turbo, and into the bottom of the pan. whereas on the back side, oil could get sucked into the assemblies, and create additional windage losses, as well as aeration of the oil, which, among other things could cause lifter to collapse and limit airflow and restrict performance. if you have motor trend on demand (highly recommended) Hot Rod Engine Masters compared what happens to power with an overfilled pan. it makes a considerable difference, and the oil being flung into the crankcase d/t poor drain routing would most likely have a similar effect.

https://www.youtube.com/watch?v=qOmMDF8sNro

------------------
"I am not what you so glibly call to be a civilized man. I have broken with society for reasons which I alone am able to appreciate. I am therefore not subject to it's stupid laws, and I ask you to never allude to them in my presence again."

"The day I tried to live, I stole a thousand beggars' change and gave it to the rich."
http://www.fiero.nl/forum/Forum2/HTML/119122.html

pmbrunelle

JUL 30, 08:46 AM

I hadn't considered the wind being pushed up vs. down depending on which side of the crankshaft you are. Interesting comment. I focused on just getting the drain line to go straight-ish and downhill.

One idea if you wanted to prevent the turbo return oil from being stirred up would be to return the oil below the oil level in the pan, with a separate vent line for the crankcase air (like how a home toilet/sink has a stack going to the roof).

ericjon262

JUL 30, 01:13 PM

quote

Originally posted by pmbrunelle:

I hadn't considered the wind being pushed up vs. down depending on which side of the crankshaft you are. Interesting comment. I focused on just getting the drain line to go straight-ish and downhill.

the way I see it, the drain will have to go from above the starter, to below it one way or another, it should end up being a pretty straight shot until it gets to the bellhousing, and then it will take a 45 nose down to the pan,

quote

Originally posted by pmbrunelle:
One idea if you wanted to prevent the turbo return oil from being stirred up would be to return the oil below the oil level in the pan, with a separate vent line for the crankcase air (like how a home toilet/sink has a stack going to the roof).

I had thought about this, and while it should work, I really don't want to end up with the oil not draining fast enough and leaking by the oil seals. I also don't like the idea of connections below the oil level in the pan, if it were to leak, it could have catastrophic results.

I have also considered running a scavenge pump, then the turbo can be mounted anywhere, and the oil return mounted plumbed anywhere as well.

notes for me:

3015/3013 106 ICL 110 LSA

[This message has been edited by ericjon262 (edited 07-30-2019).]

Will

JUL 31, 12:36 PM

Turbo drain above the static oil level works out way better. The aerated oil has much more cross sectional area to expand into the crankcase than if it has to pile up in the drain.

ericjon262

JUL 31, 12:48 PM

quote

Originally posted by Will:

Turbo drain above the static oil level works out way better. The aerated oil has much more cross sectional area to expand into the crankcase than if it has to pile up in the drain.

that was my thought too, because the oil leaving the turbo will be more aerated than the oil in the pan, it will be less dense, therefor want to float on top of the oil in the pan, with the oil entering below the level of the oil in the pan, it will have to generate a head to overcome this and flow into the pan.

Another consideration for putting the drain on the front of the pan, is that under forward acceleration, the oil will be pushed towards the back of the pan, towards the drain, possibly entering it, and the oil attempting to drain into the pan has to push against gravity and acceleration. on the flip side, the front of the pan will experience the same thing under braking, but, you're not typically very high in the revs while braking compared to acceleration, so oil flow is reduced. and less has to drain.

Joseph Upson

JUL 31, 01:13 PM

Make sure it's above the pan level because regardless of it being aerated or not, it will back up into the tube if there is oil covering the outlet into the pan. I learned that lesson back in 1996 on my first Fiero turbo build. Make sure you are in the happy medium range for oil flow as well because a high oil flow through the turbo (from high pressure at the inlet) can potentially overrun the drain rate.

The drain on my last build was on the back side above the pan oil level with a less than optimum gravity drain height at about 3" height difference between the bung on the pan and the turbo outlet. I installed an electric pump as a bypass below the primary by adding a "T" fitting, but after installing a restrictor to scale back the free oil flow to the turbo, I never had a problem with oil backing up into the cartridge and exiting into the exhaust, even though after the elbow from the turbo drain the tube was almost level. I did use a 3/4" drain tube to maximize return area.

ericjon262

JUL 31, 01:36 PM

quote

Originally posted by Joseph Upson:

Make sure it's above the pan level because regardless of it being aerated or not, it will back up into the tube if there is oil covering the outlet into the pan. I learned that lesson back in 1996 on my first Fiero turbo build. Make sure you are in the happy medium range for oil flow as well because a high oil flow through the turbo (from high pressure at the inlet) can potentially overrun the drain rate.

The drain on my last build was on the back side above the pan oil level with a less than optimum gravity drain height at about 3" height difference between the bung on the pan and the turbo outlet. I installed an electric pump as a bypass below the primary by adding a "T" fitting, but after installing a restrictor to scale back the free oil flow to the turbo, I never had a problem with oil backing up into the cartridge and exiting into the exhaust, even though after the elbow from the turbo drain the tube was almost level. I did use a 3/4" drain tube to maximize return area.

a 3/4 inch line would be tight where I want to put it, it would have to be squished a bit to fit, I'll probably end up doing 5/8". that being said, from the turbo to the bellhousing will be a downangle, and the bellhousing to the pan will be damn near vertical straight down. I don't think I will have problems, even with 5/8"

Joseph Upson

JUL 31, 02:40 PM

quote

Originally posted by ericjon262:
a 3/4 inch line would be tight where I want to put it, it would have to be squished a bit to fit, I'll probably end up doing 5/8". that being said, from the turbo to the bellhousing will be a downangle, and the bellhousing to the pan will be damn near vertical straight down. I don't think I will have problems, even with 5/8"

As long as the outlet is clear you will not have a problem. When I had the oil backup incident the turbo was sitting over the bellousing of an automatic, draining to the front side of the pan and even at that height, the oil still backed up to the turbo as the revs climbed with the drain fitting just below the oil level of the pan. Make sure you have good crank case ventilation also, because combustion gasses can also force oil past the exhaust seal.