88GT Road Race car build with a 3.4TDC (Page 14/18)
darkhorizon DEC 09, 08:26 AM
Technically the throttle by wire is just an auto blip for downshifting, but yes its an auto rev match. I was going to make this retain elec throttle body no matter what system I went with.


quote
Ironically, that LS4 is probably lighter than the 3.4 TDC. And it'll have almost double the HP.



Lots of feelings here...

1. I think its something like 120lbs lighter when the pennies hit the floor, lol. Iron block and these massive 4 cam heads are no joke.
2. The power is something that really bums me out. I had "full" 250ish whp that the modified intake and fancy headers gave me out of the TDC for a few laps at the track this year when it suddenly decided it wanted to not be a 30 year old antique.. and it was dead nuts reliable in the oil department as long as you ignored the slow leaks it had. I know the oil performance is not going to be as good in the LS4. The cam and intake combo I have planned for the LS4 will put me up in the 380 range to the wheels, so yes it will be double the 160whp that it made most of all year due to it running bad, but it will only be about 50% more than the "true potential" of this super nice TDC setup. If i was smart and left the LS4 mostly stock I would only be looking at a 25% increase to power peak to peak, with only a little bit of "powerband" improvement.
3. I'm really just tired of dealing with old junk. Being able to run a 2020 standalone ECU, using a 2010+ era transmission on a Gen4 LS motor really puts me into an age bracket that isnt about to be featured on American Pickers any time soon. I already have multiple companies that want to work with (for) me to develop adapters, horsepower, tuning, and even aero work on this car the second I've mentioned that its going to be using modern parts.


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This is gonna be awesome! (if it works )



Its going to work, that is for sure. It will be awesome if its reliable AND I dont somehow spend $5000 doing it. One thing I may mention is that I do NOT expect this transmission to be street friendly for quite awhile. I expect that the 1st gear start is going to be rough and light throttle shifting a little jerky. Its the most common gripe of the transmission control scheme I'm using but has been reported as completely fixed in the latest software revision as of just a few months ago.
Blacktree DEC 09, 02:12 PM
In any case, the new drivetrain will be more powerful AND have better weight distribution. Should be a big improvement!
darkhorizon JUL 13, 03:47 PM
Small update... Ordered all the electronics for the LS4 swap and I'm probably going to bolt it all onto the 3.4 so I can run it while I wait for the time to finish the LS4 DSG swap!
zkhennings JUL 19, 11:26 AM
Very interested in seeing where this goes, I would love to have a Fiero track car.
darkhorizon JUL 20, 01:14 PM
Its fun to think about the first few thousand posts I've had on this forum I was building an entire racing fiero for what this stuff costs, lol. Wiring should be here in a few days, I ended up ordering a chinese standalone harness for $200 assembled fully for a Gen4 LS ecu. Plan is to grommet it and shove it through the firewall and terminate what i need into the new ECU.
fieroguru JUL 20, 07:20 PM

quote
Originally posted by darkhorizon:
Its fun to think about the first few thousand posts I've had on this forum I was building an entire racing fiero for what this stuff costs, lol.



Isn't it amazing how priorities change over time and the areas you chose to spend your time or your $$$ shift significantly.
darkhorizon JUL 20, 09:23 PM

quote
Originally posted by fieroguru:


Isn't it amazing how priorities change over time and the areas you chose to spend your time or your $$$ shift significantly.



The funnier part is I'm taking this picture in my R35 GTR parked in front of my commercial property that I keep my cars at, lol.

Also I replied to your PM from last year today.... the block is absolutely going to hit the axles, but it looks like an angle grinder will have no issues taking off pointless hunks of the block and or oil pan to make room.
La fiera JUL 24, 11:27 PM
"I had measured my MG 4cyl and V6 with trans with intake, starter and most accessories when I did my conversion. The accessories can make a bit of a difference. I weighed one then the other. The V6 package came out about 15lbs heavier which is a couple of big macs and a milkshake!"

So that is 415lbs on the 3.4L platform.
LS4 Total Engine Weight= 478 lbs (does not include power steering pump, wiring harness, or computer! "GM LS4 V8 website INFO".
That's 478lbs and a wider foot print at the rear of the Fiero. It's like comparing 500lbs on a 12"x12" inches area VS a 500lbs on a 24"x24" area.
The weight is displaced on a wider patch so it will seem heavier.

[This message has been edited by La fiera (edited 07-24-2022).]

darkhorizon JUL 27, 08:31 AM
Some random progress pics. Bought a gen4 LS harness off ebay and cut the connectors off it. Things are going really well with just simply swapping the plugs to the ECUMaster ecu plugs but it does take about 6 hours to do so for some reason.. about 80 wires.

LS2 throttle body was installed using a LS1 to LS2 tb adapter off ebay for $11, pretty sweet deal there. I'll be using some new injectors I found in my injector box as well. No idea what they are but they should work as they are 60mm and EV6 connectors.
La fiera JUL 30, 10:11 PM