Put the car on a DynoJet Dyno today and pretty much met my goal of 100 more HP than the old SBC/Getrag swap!

382 wph @ about 6600 rpm


List of mods:
5.3L LS4 - stock heads and lower end
224/232 New Era DoD camshaft with pushrods/springs
Stock LS2 intake, injectors, Throttle body
Stock LS7 MAF and exhaust manifolds
4" cold air intake
Magnaflow 3" in dual 2.5 out exhaust

6 speed manual FWD transmission
12lb aluminum flywheel
Spec stage 4+ 10" clutch

 

Awesome !! What the NewEra cam run?

 

That's LS3 power. Good job!

What's the idle like compared to stock with that camshaft?

 

This is their "High Lift" version and was about $750 for the cam, pushrods and springs. I wouldn't recommend it since you can probably get a custom DoD compatible one for less $$$ now. Mine is also installed advanced a substantial amount vs. dot to dot to bring the power down from the stratosphere.

 

Manual Fieros typically have 12-15% driveline loss, so its probably 430-450 flywheel hp.

I have it idling at 800 rpm and it is has some lope to it. The 12 lb flywheel and minimal off idle torque take some getting used to for driving in stop/go traffic, but I am getting more used to it.

 

That's a lot of wheel powerhorse!

 

Is there anyway I can get info on where you got the flywheel and clutch? I just bought a f40 6-speed and already have a 5.3 but was having trouble finding a flywheel and clutch setup to work with 5.3 and f40! Thanks and great build

 

that's awesome. should also post some pics of the engine bay, the build etc. i would have liked to check them out... great job

 

DAMN, I bet thats fun to drive!

 

looks great man , congrats on ls3 power and sub corvette weight!!

 

The flywheel I designed and turned from a hunk of aluminum on a manual lathe:




The flywheel is a Spec Stage 4+ from a 4.0L Ranger... but the flywheel has to be designed (flywheel thickness and pressure plate bolt pattern) for this clutch.



The only other LS4/F40 that is currently running used a 7 1/4" LS1 button flywheel and fabbed up a custom HTOB for it to work.

 

Thanks! Yes, I have lots of pictures and a build thread. Here are a couple of good engine bay pictures:






The long detailed build thread is here - lots of pictures and commentary:
http://www.fiero.nl/forum/Forum3/HTML/000123.html

This one is here on ls1tech and is more of a summary, but still shows quite a bit of detail:
https://ls1tech.com/forums/conversio...peed-swap.html

 

Yes, it is quite fun to drive. It has been my daily driver since I finished it. It took a little time to get accustom to launching the car from a stop light without looking like a 16 year old learning to drive a stick (light flywheel, minimal off idle torque, large throttle body), but now I can drive it like a normal car.

Thanks! I still have quite a bit to do to the interior and paint of the car to make it nice, but for now it is a very fun toy!