88GT Road Race car build with a 3.4TDC (Page 13/18)
darkhorizon DEC 04, 01:43 PM
My upcoming winter upgrade.... Breaking into some extreme new grounds here, pretty excited but also very nervous as this is a big pile of investing in things that not only have never been done but hell I've barely even heard people dream about.
RacerX11 DEC 04, 04:59 PM
Do I spy a DSG? Count me interested.
Dennis LaGrua DEC 04, 07:37 PM
Great project and you have no doubt done some great mods to your Fieros. I just have one question. The 3.4TDC engine and the trans weighs in at something like 575 lbs. That seems like a lot of weight for a road racing car. The lightweight Ecotech would seem a better choice but perhaps you have already looked into that.

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" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

[This message has been edited by Dennis LaGrua (edited 12-04-2020).]

Rickady88GT DEC 05, 07:21 AM

quote
Originally posted by RacerX11:

Do I spy a DSG? Count me interested.



Looks that way to me.
Cool
It looks small? Is it the wet clutch 6 speed?

[This message has been edited by Rickady88GT (edited 12-05-2020).]

darkhorizon DEC 05, 09:12 AM
You guys are sharp. It is indeed the DQ250 from a VW. its VERY compact, although strangely enough about 3 inches "longer" than the 4t65e... and almost heavier than a 4t65e... Its a dual wet clutch, rated for about 350 torque in the application I will be running on it. Its out of a 2009 Jetta turbo.

Current loose plan is as follows..

1. Adapt VW flywheel to LS4 crankshaft, as thin as I can manage.
2. create a flat-ish adapter plate from the LS4 to the DQ250, use the flywheel/input shaft to establish centricity. the bellhousing of the VW trans is like a direct copy of the 60degree v6 pattern, but its micro, like 9inches in diameter vs the 12-13 that the 60degree pattern is.
3. find VW axles that fit (mildly possible, have a ton of adjustment in the LCA for a longer than stock fiero axle)
4. install VW hubs into the fiero knuckles.
5. Run DSG using all of the CAN signals sent out by a stock Jetta
6. Run a standalone ECU on the LS motor, feeding my race dash.
7. Install a little twist knob on the dash, and some cool ferrari challenge paddle shifters on the steering wheel for the gear selection, lol

LS4 has a LS2 intake, big cam, and some oil mods. Should easily make 380-400whp.
darkhorizon DEC 05, 09:16 AM

quote
Originally posted by Dennis LaGrua:

Great project and you have no doubt done some great mods to your Fieros. I just have one question. The 3.4TDC engine and the trans weighs in at something like 575 lbs. That seems like a lot of weight for a road racing car. The lightweight Ecotech would seem a better choice but perhaps you have already looked into that.



Well, if you see the latest post you'll see that its no longer either of those BUT it isnt getting lighter. The reality is weight isnt that big of a deal. This car is already pretty light, around 2400lbs, and saving a few hundred here or there isnt going to help me nearly as much as another few hundred horsepower and instant shifts will. And with road racing you need to put a severe power discount on anything that would be common in a street going fiero. a 600whp 3800 is something I could easily do, but not something that would be reliable without significant stuff like a drysump oil system, fancy cooling, and other things.
Rickady88GT DEC 06, 08:52 PM
I have to ask, how are you planning to program the transmission? Can it be run on a primitive system? Is there an aftermarket system?

In my mind I am juggling the adapter plate and crankshaft adapter, and NOT making them to thick to fit.
I recommend at least a basic rebuild of the transmission before installation. Those have a reputation for the control unit failing and obviously the clutch system replacement. The biggest issue with the wet clutch is that it shares the oil with the grearsets. That means that the shedding clutch material is also running through the bearings and gearsets. The new transmissions have a pump that filters and circulates the oil, even a cooler is included.
darkhorizon DEC 07, 08:34 AM

quote
Originally posted by Rickady88GT:

I have to ask, how are you planning to program the transmission? Can it be run on a primitive system? Is there an aftermarket system?

In my mind I am juggling the adapter plate and crankshaft adapter, and NOT making them to thick to fit.
I recommend at least a basic rebuild of the transmission before installation. Those have a reputation for the control unit failing and obviously the clutch system replacement. The biggest issue with the wet clutch is that it shares the oil with the grearsets. That means that the shedding clutch material is also running through the bearings and gearsets. The new transmissions have a pump that filters and circulates the oil, even a cooler is included.



https://www.wiringspecialti...e-engine-management/

These polish ecu guys have the ability to emulate the CAN bus accordingly. Its mostly a mystery if it actually works, as almost nobody has used it but I'm not that afraid.



The TCU isnt that hard to get at either, so I can make tweaks to it directly. I will be using a KESSv2 to flash the trans, and some stuff I found on the internet to modify the software. There are 2600 parameters in the software that I have the ability to modify, oof!

I'm not too sure what I will do with the trans. This was a very not abused trans and while I'm going to clean it up a bit and make sure the fluid and stuff looks ok, the clutch replacement is an expensive and complex job that I might save for later. I want to find out if this thing even works at all before I invest much into it, and honestly its not more than a few hours from being back out and on the ground again once its in the car.
Blacktree DEC 07, 01:12 PM
This is gonna be awesome! (if it works )

Ironically, that LS4 is probably lighter than the 3.4 TDC. And it'll have almost double the HP.
Rickady88GT DEC 07, 06:00 PM

quote
Originally posted by darkhorizon:


https://www.wiringspecialti...e-engine-management/

These polish ecu guys have the ability to emulate the CAN bus accordingly. Its mostly a mystery if it actually works, as almost nobody has used it but I'm not that afraid.



The TCU isnt that hard to get at either, so I can make tweaks to it directly. I will be using a KESSv2 to flash the trans, and some stuff I found on the internet to modify the software. There are 2600 parameters in the software that I have the ability to modify, oof!

I'm not too sure what I will do with the trans. This was a very not abused trans and while I'm going to clean it up a bit and make sure the fluid and stuff looks ok, the clutch replacement is an expensive and complex job that I might save for later. I want to find out if this thing even works at all before I invest much into it, and honestly its not more than a few hours from being back out and on the ground again once its in the car.



It looks like throttle by wire for rev matching?