LS4 / F40 swap - fieroguru (Page 211/216)
fieroguru AUG 31, 04:53 PM
Fab table is right side up and fully assembled now!

Not a show quality paint job, but good enough for a work table.
I still need to use the DA sander on the top to remove some over spray and surface rust and then coat it with some oil.
It is 39" from the floor to the top at the lowest setting.
It also weighs 620 lbs.

[This message has been edited by fieroguru (edited 08-31-2025).]

fieroguru SEP 01, 04:31 PM
Fab table is done!

Moved to the proper location, leveled, top sanded with 180 grit with DA sander, then light coated of oil.


Now i get to start making all the fixtures and hold downs!
fieroguru SEP 06, 09:32 PM
Started working on some weight reduction.

Replaced the 12" springs with 10" springs - reduced 1.2 lbs in total




Removed one of the original lateral link relocation brackets for some custom lighter ones: reduced 1.4 lbs.




Working on the brake brackets for a different rear rotor that is slightly smaller, but 2+ lbs lighter per side.

[This message has been edited by fieroguru (edited 09-07-2025).]

dskebo SEP 07, 10:21 AM
I would like to buy your original brackets from you.
fieroguru SEP 07, 01:34 PM

quote
Originally posted by dskebo:
I would like to buy your original brackets from you.



Which brackets: Lateral LInk Relocation or 13" brake kit? How much you offering?
fieroguru SEP 07, 06:26 PM
Finsihed up the brake brackets:


Here is the caliper, bracket, and mock up rotor installed: Now waiting for drilled/slotted rotors to be delivered.


Within my rotor database, there are close to 350 different rotors. If I filter with a rotor thckness that allows retaining stock 88 calipers and overall rotor diameter between 12.0 and 13.0", there are 22 applications.

The lightest is the 12" 88 C4 front rotor @ 13.5 lbs and has 1.12 lbs/inch of diameter.
The nearly 12.5" rotor I am switching to is the 2nd lightest @ 14.0 lbs and has 1.13lbs/in of diameter.
The 13" traverse rotor currently on the rear is 1.39 lbs/in of diameter.

With this change, I will drop some rear, unsprung & rotational weight, and likely allow fitment of a 16" wheel (without needing to modify the calipers) for drag racing.

While I have the car down (no longer than 2 weeks), I am mocking up some intercooler options. I have both A2A and A2W setups to play with. The A2A is the most weight efficient, but likely less effective than the A2W setup.

Below is one location for the A2W. It will require some sheet metal trimming/denting to get it level. I will have to add another bleeder port to get all the air out of it. It is also the absolute shortest length of charge pipe. Doesn't really go with my stealthy vibe, but I could paint it black (and insulate it) so it blends into the engine bay and is less obvious. After a 2 hr drive at interstate speeds on a 70 degree day, both decklid vents are 119 degrees. On the same trip the IAT was showing 105 degrees most of the time, so a slightly cooler location would also help.

dskebo SEP 08, 10:27 AM
You have a PM.
pmbrunelle SEP 10, 07:47 AM

quote
Originally posted by fieroguru:
Below is one location for the A2W. It will require some sheet metal trimming/denting to get it level. I will have to add another bleeder port to get all the air out of it. It is also the absolute shortest length of charge pipe. Doesn't really go with my stealthy vibe, but I could paint it black (and insulate it) so it blends into the engine bay and is less obvious.



The car wasn't fast enough without the intercooler?

With a 3D-printed plastic insulating case, this could be made to look like an air filter enclosure.
fieroguru SEP 10, 09:36 PM

quote
Originally posted by pmbrunelle:
The car wasn't fast enough without the intercooler?



Just trying to max out the combo. Already have 450 walbro, 1050cc injectors, and a 9 1/4 twin disc clutch.
With the current rear wheels/tires, at 7200 rpm the car will top out at 135 mph in 3rd gear. I have reached this level many times while tuning, I just want to get there quicker.
Not really a 1/4 mile enthusiast, but I do have the opportunity a couple times of year to run w/o normal NHRA tech requirements.

1st and 2nd gear are traction limited (and I will be limiting boost by gear and throttle opening by RPM), so to minimize ET it needs to pull as hard as possible in 3rd gear from 85 to 135.

4th gear would only be needed for standing mile events, but within an hour is a 2000hp dyno capable of 200 mph, and 7200 in 4th is 187 mph. I can rent this for 4 hrs for $500, which is my plan when I am ready.



quote
Originally posted by pmbrunelle:
With a 3D-printed plastic insulating case, this could be made to look like an air filter enclosure.



Not generally a fan of "covers", but that might be a good compromise. I might start looking for OEM plastic air filter housings that could be used as a cover.

pmbrunelle SEP 11, 08:53 AM

quote
Originally posted by fieroguru:
1st and 2nd gear are traction limited (and I will be limiting boost by gear and throttle opening by RPM), so to minimize ET it needs to pull as hard as possible in 3rd gear from 85 to 135.



I am dissapointed that the Haltech is not "torque-based", in the sense that the accelerator pedal doesn't request a torque, and then the Haltech would figure the required throttle opening and boost pressure.

I'm working on a (non-Fiero) naturally aspirated project with a Haltech Nexus, but I want the accelerator pedal to roughly represent torque, so (in conjunction with a MAP vs. RPM vs. TPS correlation) I need to do some calculations in Excel beforehand to populate the pedal-to-throttle table.

[This message has been edited by pmbrunelle (edited 09-11-2025).]