 
     |
| 88GT Road Race car build with a 3.4TDC (Page 1/18) |
|
darkhorizon
|
JUN 09, 02:02 PM
|
|
This thread kinda started in General, so I'm moving it over here for more talk about stuff thats technical. Took it to the track this weekend for its first little shake down and here is what I've found. I also have a few pics of the front suspension.
First things first, the car did drive pretty great!
Front end:
There was some loose suspension parts somewhere in the car, most noticeable on left hand braking turns.... No smoking gun on this yet but I did find a loose tie rod end on the driver front. As you can see in the pics the passenger front has a bump steer correction kit installed... yet there is a stock tie rod end on the driver side that was loose due to a loose jam nut.... oh well. Otherwise the front end felt good, shocks are in good shape and although the steering rack seems to have a pile of gravel in it overall worked fine. I also was able to find that the knuckles I have are HT drop knuckles specifically designed with 88 brakes and 87 spindles.
Rear end:
The Maxima koni shock conversion seems to be working just great. However I did have the camber adjustment in the knuckle slip and I lost all the negative camber I had back there... Easy fix and luckily it only caused me to slip off the track really pushing a slow right hand turn. I suspect the rod end 88 lat links are starting to wear out a bit but I havent looked that close at them, but they felt ok on the track so far. I plan to replace these soon.
Drivetrain:
The LS1 throttle body and super cool headers are likely causing issues with the tune. The cooling system was GREAT i mean super great, but I had issues keeping the thermostat in it, it kept twisting and popping out of the stock fiero thermostat housing that was welded onto the 3.4 tdc stuff. That caused issues because the tune became much better the warmer it was. I looked at the chip in the ecu and it looks stock, but it could have been UV erased and reflashed (highly doubt it). Previous owner swore to me this was tuned well when he sold it to me. I ordered a chip kit and will do my own tune for this soon. The symptoms were a complete power cut if I gave it more than 15% throttle under 3500rpms, and a severe drop in power after 5000rpm.... Which was nice because the absolutely flawless Quaife LSD equipped W41 transmission let me keep it right in the sweet 4000-5000rpm spot all weekend without much effort. Trans also shifted better than my s2000 somehow even with crappy cables and stuff... I commented I couldnt mis-shift that car no matter how hard I tried to lol. Was pretty quick when it was running right!
Brakes:
My gosh the brakes sucked. EBC yellows on some old beat up rotors were a horrible choice but I was able to turn laps so I am not complaining too much here. I am in the search for a new brake system that is for sure. I have a unique situation with the drop knuckles and an absolute hatred for the 88 calipers... I refuse to use these as they are expensive, poorly designed, and there are absolutely no performance pad options for them... at least without really begging some of my friends at PFC. I would love to have a conversation here with anyone that would like to suggest a good combo, but after a few hours of research I've settled on the standard corvette rotor upgrade commonly used with stock calipers, but putting on the $110 each brembo CTSV calipers with an adapter plate... both front and rear and I'll balance braking bias with a prop valve and pad compound.
Weight:
I put the car on scales and was happy to find a neat weight balance. I didnt write the numbers down but it was basically perfect left to right and had about 1425lbs on the rear and 1225 on the front, making for something like a 56/44 weight balance. Combined with little brake dive and front lift on accel it was a really balanced car to drive on track.
Aero:
The front end has some serious downforce that ramps up over 50mph. I was able to take high speed corners with zero understeer even with the LSD doing its thing but at low speeds it would understeer pretty bad sometimes (I have a few fixes for this in shock adjustment and some alignment/tire issues I had, so mostly ignoring this for now). The rear felt planted and consistent which is nice but I would like to add a big wing soon so I can really balance it out at speeds over 70mph.
|
|
|
|
Blacktree
|
JUN 09, 06:40 PM
|
|
So you've switched from drag racing to road racing? Pretty cool. I've always thought the Fiero was more suited to road racing, anyway.
The front suspension looks to be the Held / Arraut coilover setup for the '88 Fiero. Just FYI, those steering knuckles are known to fail at the welds. I'm not trying to scare you, but maybe have the welds inspected for stress cracks.
Also, I would strongly suggest some ducting to cool the front brakes. It'll have a big impact on pad / rotor life, and will reduce brake fade. Those CTS-V calipers are a popular upgrade on heavier cars (like Camaros, for example). So they should do fine on your Fiero.
Edit to add: Looks like the CTS-V calipers require an 18" wheel.[This message has been edited by Blacktree (edited 06-09-2020).]
|
|
|
|
cvxjet
|
JUN 09, 08:11 PM
|
|
A) Do you have original 88 Spindles or the Held spindles?
B)Rather than go to Gigantic brakes, make sure the originals are working properly with good pads, and definitely duct some cooling air to them.
I have an 85 SE V6 w/ 3.4 F-body- 5 spd-88 rear + brakes all around (Fronts are 12' discs on original 85 suspension)
I corner carve on back roads all the time; Usually going up-hill to not abuse the brakes, but since the conversion to 88 brakes I have been running it hard down hill- No fade of any sort....(I admit this treatment is not as harsh as track racing, but I do believe that some of the gigantic brakes on modern cars is overkill- and they require giant wheels which weigh more, killing performance of Brakes/engine/suspension....try to stay light but well-prepared!
|
|
|
|
wftb
|
JUN 09, 09:48 PM
|
|
|
What track were you at ? Looks like you are going to have a great track car with a little more sorting. Thanks for posting this. ------------------
86 GT built 2.2 ecotec turbo
rear SLA suspension
QA1 coilovers on tube arms
|
|
|
|
La fiera
|
JUN 09, 09:55 PM
|
|
I don't know about the CTS-V calipers but for the F-body metric caliper there's a plethora of pads compounds.
I run Hawk DTC-30 front pads and you can literally run with the brake pedal depressed and it will not fade.
|
|
|
|
Gall757
|
JUN 09, 10:01 PM
|
|
| quote | Originally posted by wftb:
What track were you at ?
|
|
Reminds me of turn 2 at Gingerman... could it be?
|
|
|
Patrick
|
JUN 09, 11:43 PM
|
|
| quote | Originally posted by darkhorizon:
|
|
| quote | Originally posted by Gall757:
Reminds me of turn 2 at Gingerman... could it be?
|
|
Whatcha figure... Fiero in picture about here? 
|
|
|
|
darkhorizon
|
JUN 10, 07:56 AM
|
|
| quote | Originally posted by La fiera:
I don't know about the CTS-V calipers but for the F-body metric caliper there's a plethora of pads compounds.
I run Hawk DTC-30 front pads and you can literally run with the brake pedal depressed and it will not fade. |
|
Camaro calipers are what I want to run, but so far I haven't found an easy way to use them as the rotors will allegedly hit my knuckles and the calipers are not easy to adapt. I run DCT 30 60 and 70 in some combination on my S2000 and CRX, AND the price of the pads in the camaro caliper are almost half of the honda pad prices.... I'm going to keep looking at the camaro stuff and see if I can figure it out.
| quote |
A) Do you have original 88 Spindles or the Held spindles?
|
|
Held knuckles built with 88 brakes and 87 spindles. To the comment on their failure being common, all the research I have done says that the older knuckles were the ones that started having these issues and not so much for my early ones. I have looked around at these and while they were bent up a little bit I never found any cracks that worry me.
| quote |
B)Rather than go to Gigantic brakes, make sure the originals are working properly with good pads, and definitely duct some cooling air to them.
|
|
I'm the first to say this to everyone, but the reality is the 88 caliper has zero performance options out there for pads... and the rotors are not the right size for what I'm trying to do either. My s2000 is roughly the same weight as this fiero and the brakes on it are undersized, and the fiero makes more horsepower. the s2000 brakes are about 11inch rotors with a big caliper using the most extreme brake pad compounds available, so the overkill I'm planning isnt that wild to me.
| quote | | Edit to add: Looks like the CTS-V calipers require an 18" wheel. |
|
I really hope that isnt the case, the goal is to run a 12inch rotor and use a ctsv caliper, but I am really planning on staying 17in wheel ready. the WCF kit claims that they are 16in wheel compatible. I may need to use a caliper that is like an acura TL brembo and not a CTSV if there is an issue with a 12in rotor. https://westcoastfiero.com/...kes-1984-1988-brembo
Yes this is Gingerman in South Haven Michigan. I will be heading to Autobahn raceway in Joliet at the end of the month, and would like to have the new brakes on by then.
| quote | | So you've switched from drag racing to road racing? Pretty cool. I've always thought the Fiero was more suited to road racing, anyway. |
|
I've been on road racing for about 5 years now with my hondas, just now messing with the idea of a Fiero race car though. Drag racing on a budget was much easier on 20 year old me's wallet, now that I'm into my 30s with a mortgage free house and a nice garage I can spend the $3500+ a year in track fees along with expensive "must have" road racing parts like brakes, safety, and reliability mods. My s2000 doesnt have a full cage in it, so I've been working on retiring it from track duty using this fiero as the replacement for my "slow" driver training beater car to turn laps in. I will say even running bad this car loved to get out there and run a hard 20 minute session which is more than my hondas have done.[This message has been edited by darkhorizon (edited 06-10-2020).]
|
|
|
|
wftb
|
JUN 10, 08:33 AM
|
|
You can have these for the price of shipping 2.3/8” pistons no one wanted to buy them
D 154 style GM metric ------------------
86 GT built 2.2 ecotec turbo
rear SLA suspension
QA1 coilovers on tube arms
|
|
|
|
darkhorizon
|
JUN 10, 09:01 AM
|
|
| quote | Originally posted by wftb:
You can have these for the price of shipping 2.3/8” pistons no one wanted to buy them
D 154 style GM metric
|
|
Its an interesting direction for sure. Lots of support for these.
https://www.speedwaymotors....eQU4C9saAqYZEALw_wcB
|
|
|
|