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ALLTRBO · 07-22-2010, 10:14 PM

Upon request, I'm posting my '88 Fiero GT V6 turbo build here. This thread won't be the full build thread, rather major updates that may be of interest. The full build thread is here, on Pennock's Fiero Forum...
http://www.fiero.nl/forum/Forum1/HTML/078498.html

This project is the main reason I didn't buy a Camaro SS, not because of cost, but because I don't need a V8 that'll be wasted 9-ways from Sunday by a little V6 car. That's just embarrasing.

Plus, I just LOVE the LLT and its technology, and the lighter weight of the V6 Camaro. Anyway...

It's an '88 Fiero GT 5-speed with a '90 Turbo Grand Prix 3.1l 60degreeV6 shortblock (for now) and a late Gen III (3400) top end being pushed by a Borg/Warner S258 with a .82 A/R T3 exhaust housing machined to fit, all controlled by a '730 ECU. I'm guessing it'll make somewhere around 350whp on ~12 psi, maybe a bit more. This is the first step. It'll help me get a base tune down and figure out the details I want to change about the real shortblock build.

Later on I'm going to build up a stout "3200" destroker shortblock using a 3500 block and a 2.8 crank with Diamond pistons (.100 over 3400 pistons) and 5.85" forged SBC rods, and I'll probably have the top end ported and a decent matching cam installed. Along with the huge W/A IC setup that I'm building for it and serious fuel delivery and a twin-disk clutch upgrade, the setup should support about 600whp on high boost (30+ psi) and race gas, with a smooth enough torque delivery that the eggshell Getrag 282 might handle it (if not, I'll upgrade to the F23, a slightly stronger but similar 5-speed). It's getting a sport/race exhaust, basically a high-flow regular exhaust, then an electronic cutout that will bypass that and route back into the tailpipes. This will keep the neighbors happy in "sport mode" and me happy in "race mode", and anywhere in between.

The suspension is also being worked over. The '88s had a suspension redesign that much improves on all earlier Fieros. It's already all rebuilt, and I'm working out the proper way to lower it without screwing up the geometry, which is an easy thing to do with the '88s (screw up the geometry, that is). There are ways... The brakes have been upgraded, and the weak wheel bearings will also be seriously upgraded, as will the wheel/tire combo.

I'm doing some body and interior mods also, and will have a custom high-quality paint job.

I recently had to sell my twin-turbo '90 IROC-Z [IMG]http://60degree*******/forum/images/smilies/icon_sad.gif[/IMG] to get the reliable daily driver 2010 Camaro, and I'm selling my 11-second AWD Talon and my stock AWD Talon, so the Fiero is going to be my only real sportscar to play with.
Because of that, I'm aiming for ZR1 performance levels... Well, other than top-speed, reliability, ride quality and refinement. I'll save about $80,000 so that's okay with me. [IMG]http://60degree*******/forum/images/smilies/smile.gif[/IMG] The initial build with the 3.1 shortblock is about 80% done.

Let me know what you think. If there's any questions I'll try to answer them, but most of it is covered in the build thread (be prepared for lots of reading). I won't be updating the thread here regularly, so don't fret if I haven't posted in a while.

BTW, a modest 350whp in this light Fiero will be equivalent to about 440whp in an SS, and the Fiero's 600whp will be equivalent to about 760whp in an SS. Though, the Fiero will hook up easier and still handle much better doing it. Oh, and it'll stop fast too.

07-22-2010, 10:14 PM	#1
ALLTRBO Drives: V8 up front and 7-spd out back FTW Join Date: Apr 2010 Location: MD Posts: 746	Project MIDTRBO... '88 Fiero GT Upon request, I'm posting my '88 Fiero GT V6 turbo build here. This thread won't be the full build thread, rather major updates that may be of interest. The full build thread is here, on Pennock's Fiero Forum... http://www.fiero.nl/forum/Forum1/HTML/078498.html This project is the main reason I didn't buy a Camaro SS, not because of cost, but because I don't need a V8 that'll be wasted 9-ways from Sunday by a little V6 car. That's just embarrasing. Plus, I just LOVE the LLT and its technology, and the lighter weight of the V6 Camaro. Anyway... It's an '88 Fiero GT 5-speed with a '90 Turbo Grand Prix 3.1l 60degreeV6 shortblock (for now) and a late Gen III (3400) top end being pushed by a Borg/Warner S258 with a .82 A/R T3 exhaust housing machined to fit, all controlled by a '730 ECU. I'm guessing it'll make somewhere around 350whp on ~12 psi, maybe a bit more. This is the first step. It'll help me get a base tune down and figure out the details I want to change about the real shortblock build. Later on I'm going to build up a stout "3200" destroker shortblock using a 3500 block and a 2.8 crank with Diamond pistons (.100 over 3400 pistons) and 5.85" forged SBC rods, and I'll probably have the top end ported and a decent matching cam installed. Along with the huge W/A IC setup that I'm building for it and serious fuel delivery and a twin-disk clutch upgrade, the setup should support about 600whp on high boost (30+ psi) and race gas, with a smooth enough torque delivery that the eggshell Getrag 282 might handle it (if not, I'll upgrade to the F23, a slightly stronger but similar 5-speed). It's getting a sport/race exhaust, basically a high-flow regular exhaust, then an electronic cutout that will bypass that and route back into the tailpipes. This will keep the neighbors happy in "sport mode" and me happy in "race mode", and anywhere in between. The suspension is also being worked over. The '88s had a suspension redesign that much improves on all earlier Fieros. It's already all rebuilt, and I'm working out the proper way to lower it without screwing up the geometry, which is an easy thing to do with the '88s (screw up the geometry, that is). There are ways... The brakes have been upgraded, and the weak wheel bearings will also be seriously upgraded, as will the wheel/tire combo. I'm doing some body and interior mods also, and will have a custom high-quality paint job. I recently had to sell my twin-turbo '90 IROC-Z [IMG]http://60degree******/forum/images/smilies/icon_sad.gif[/IMG] to get the reliable daily driver 2010 Camaro, and I'm selling my 11-second AWD Talon and my stock AWD Talon, so the Fiero is going to be my only real* sportscar to play with. Because of that, I'm aiming for ZR1 performance levels... Well, other than top-speed, reliability, ride quality and refinement. I'll save about $80,000 so that's okay with me. [IMG]http://60degree*******/forum/images/smilies/smile.gif[/IMG] The initial build with the 3.1 shortblock is about 80% done. Let me know what you think. If there's any questions I'll try to answer them, but most of it is covered in the build thread (be prepared for lots of reading). I won't be updating the thread here regularly, so don't fret if I haven't posted in a while. BTW, a modest 350whp in this light Fiero will be equivalent to about 440whp in an SS, and the Fiero's 600whp will be equivalent to about 760whp in an SS. Though, the Fiero will hook up easier and still handle much better doing it. Oh, and it'll stop fast too.