Semper91-RS

Wow. Just... stunned man. There's respect to be given for all the work you've put in. It's just amazing..

LS4 swap

iTrader: (1)

Thank you, but it is not done yet. I still have a lot of work to do.



One thing that bugs me is that I used the stock Monte fuel sending unit in the Fiero tank. The Fiero tank only holds 11gal. I don't know what the monte can hold, but the difference in size really screws up the D.I.C. miles remaining estimate. It is nearly half what I can actually go. It starts off over 400 miles but I can only get 200-250 depending on how heavy my foot gets.
It sure would be nice if I could recalibrate that?

The Manalishi

iTrader: (3)

That is a very nice build and the attention to detail is amazing. Great job and I bet its a ball to drive.

LS4 swap

iTrader: (1)

HaHa, yah its fun to drive.
I have to have a light foot on corners from a dead stop. The 255 45 17's brake loose easily and has a bit of snap steer at throttle lift. The balance of steering with the throttle and steering wheel is a trick, at the limit.

The Manalishi

iTrader: (3)

I imagine. I have 275's and I still can't hook, I have more power but the car is heavier. I figured it wouldn't be too bad in throttle lift but I don't know what the weight distribution is. I would assume, wrongly apparently, that a mid engine V-8 Fiero would be a good handling car. Is it just too much power or is it a weight distribution issue?

TiredGXP

iTrader: (2)

In stock trim, a Fiero has approximately 58% weight on the rear wheels. Hard to say how this may change with the LS4/4T65 combo, but since the engine is just in front of the rear wheels, I doubt the difference is terribly significant.

The Manalishi

iTrader: (3)

Which would counter throttle lift issues. He stated he had them so either the weight is significantly different or the power is too much for the chassis to handle. Mid engine cars are usually neutral or they understeer. This isn't the case in this car.

TiredGXP

iTrader: (2)

And he has an 88, which has a superior suspension set-up than earlier models. LS4 has more than twice the power and torque of the engine that GM put in this chassis, so might have an effect.

It's been a while since I checked out the thread over on PFF so I don't recall if he upgraded bushings/struts... Fiero's essentially have a FWD set-up in the rear, so torque steer could still be an issue.

Breathing Fire

Wow man that is an amazing job! I was just browsing and saw this. Amazing!! Always loved the Fiero. Such a bad *** car. Way ahead of its time in design IMO. The world of cars is a better place because of people like you. It takes some serious brain power to pull that off as perfectly as you did it.

LS4 swap

iTrader: (1)

I think you hit the nail on the head. The stock rubber bushings are still in it. I have no idea if they were ever changed but the car has over 250,000 miles on it.
The quad cam 3.5 Short Star was rated at 215hp and I did not have any of the snap steer. I now have about 100 extra hp over that swap and I think the bushings just cant take it. The car rides beautifully and very quiet so the rubber would have been fine for a while longer if I did not swapped in this V8. Looks like I will just do polly in the rear and see what happens. I want to keep the rubber in front because I like the smooth ride, so I will replace it with new. My opinion is that the front of an 88 does not "need" polly like the other Fiero's to handle better. The rubber just needs to be in good shape and it will handle great. The rear is a little different. It has more bushings than the front and with the 300+hp can get more "twisted", so polly should help.

LS4 swap

iTrader: (1)

Thank you, the car still needs some work but is a lot of fun to drive.
I appreciate custom cars because I know how much blood sweat and tears go into them. So talking to people about the car is making all the work worth while.
At the Coast on highway 1 I noticed several people stopped and looking at the car. One person was taking pictures of it so I opened the deck lid for him. 20 min latter I went back into the restaurant to eat. Then after breakfast more people were looking at it. So I must have talked for 45-an hour about hot rods.
I get to hear about lots of cool stuff and show off my car at the same time. Infact today I was a little late to work because I was stopped by a guy in the parking lot who was asking questions about the car.

LS4 swap

iTrader: (1)

I do have a few questions about HP tuner for the 06 Monte LS4.
I want to get a tune done on it so my question is what are the most common things changed on a "high performance" daily driver.
The stock tranny shifts so unbelievably smooth in this car that I literally cant feel it shift sometimes. So I know I want to install a shift kit. The car is lighter than the 06 Monte that the engine came from so I am not concerned about hurting the tranny. I just don't want the extra hard shift setting when I install the kit. Other than the none stock air box and "free flowing" exhaust the drive train is stock. I have no muffler, just a cat and resonator tips and it does not have the typical code like the catless down pipes are getting.

Any and all advice is greatly appreciated.

07carlocrusader

This is inspirational!! Love it,.....

TiredGXP

iTrader: (2)

Well, you can play with shift pressures a bit to make the shifts a bit crisper.

I'm not suggesting that you go all the way to max pressure, but if you ever want to find out what max pressure shifts feel like, unplug the maf and go for a short drive. For whatever reason, GM programmed the transmission to provide max pressure when a MAF failed - probably to ensure people brought the vehicle in for servicing. The downshifts are brutal.

Sounds like you've done relatively few mods, so your tuning requirements aren't too extensive, with your intake and exhaust mods, you probably need to have the VE table and maf curve tuned.

Stock tune delays entry into PE mode, have it come in around 2500. The PE fueling table is **** - as in ridiculously rich at higher rpm, you probably want to set the PE AFR to ~12.8 across the board. this will help power in the upper rpm range. PE enrichment rate should be increased to 1 from .02 - all this does is decrease the time it takes to move to your desired PE AFR

If you've upgraded valve springs, consider increasing shift points and rev limiter - has a benefit in first gear acceleration.

I removed all engine torque management and about half of the transmission torque management

The engine can take a bit more timing in the higher RPM and "dyn cyl air" cells, no real point in bumping timing below 2000 RPM, I just got knock when I tried.

There's a few other things that might be adjusted, but this is most of the basics.

The torque management tuning won't fix your problem when accelerating around a corner, the only way to avoid this is to disable differential score protection. Problem is that that puts the differential clutches at risk. Since you are rear wheel drive, you might get away with it. I think Ryan did this on BLKCOFY's LS4 swap.

LS4 swap

iTrader: (1)

Cool thanks, I will pass this on to the shop that will tune the car.

LS4 swap

iTrader: (1)

Did not get a tune for the car yet, but did get some "traction control" settings taken care of

[YOUTUBE]http://www.youtube.com/watch?v=OE-VqF94wBQ[/YOUTUBE]

[YOUTUBE]http://www.youtube.com/watch?v=epoLQQU73i0[/YOUTUBE]

LS4 swap

iTrader: (1)

[YOUTUBE]http://www.youtube.com/watch?v=epoLQQU73i0[/YOUTUBE]

jeep107

OK, I have got to know...read your build report and you say you plan to sell this sometime and build another amazing machine. Sure would be nice to get my hands on this one as I am pretty positive I could never even begin to build one as nice....when ya sellin it to me??

LS4 swap

iTrader: (1)

Thanks, the car is far from complete but I will continue to work on it till some one makes a good enough offer or till I just get another car to build.
I would love to have a Saturn Sky or Pontiac Solstice to swap V8 into.

firechicken76

iTrader: (14)

Just saw this on youtube, thought i would do a search on here, and its on here! anyway, i really like this swap, as a previous owner of a fiero, i know how much fun they can be, cant imagine how one would be with an ls4.