MrVette90l98mt

I'm wrapping up the research phase for my LS3 EROD swap but I have a few questions before dropping the money. Car is a fully loaded 1990 L98 car.

1) Quick time Bell housing height and fork ball stud location the same as OEM ZF bell?- Found this weld on slave cylinder mount for quick time bell housings (RM-6018E) and was wondering if a stock slave will bolt up to this and be able to retain my stock type pull type clutch (SPEC stage 2 Kevlar <10K miles, I know I need new 168T LS flywheel, sourced from SPEC)

2) Engine mounts (L98 cars)- are there any specific LSx plates or will generic SBC Gen 1 to LSx plates work with stock C4 sbc mounts? LS3 to ZF6 any need for auto C-Beam, etc.?

3) High mount A/C compressor, R4 or Sanden 508- has anybody use the Holley Sanden high mount A/C compressor with C4 LSx swaps? It looks like the mount system for the sanden hangs out too far and will hit the fender liner and the pressure lines will hit the hood. I know the R4 will fit, I assume with Holley mount...I saw a youtube video of an LS3 EROD '87 C4 on dyno and saw the R4 compressor installed on the LS3. Or will my stock compressor fit with mods to the bracket?

4) Tach / guages, use both ECMs?-Is it feasible to run 2 ECM's in the car? The EROD LS engine controller for just the engine and use the O.E.M L98 ECM feed with minimum signals to keep subsystems happy (BCM, FX3, C68 auto climate, ABS). Are sending units calibrated differently? LS3 EROD Manual trans comes with ecm 19257236

5) What subsystems will not work without original ecm? 1990 L98, FX3, ABS, C68 auto climate car

6) Can the engine and ZF trans be pull together from the top with car on jack stands? (with hood removed)

Thanks for the info!

aDigitalPhantom

1. That bracket uses the LT1 Camaro slave cylinder, and in this case is for a push type clutch.

2. Not sure

3. The holly bracket for the sd508 will fit, but you may need to trim a small piece off the hood.

4. Not sure

5. Not sure

6. Yes. Not sure if you need remove the shifter or not.

aklim

From what I understand, the gauges won't be that big of an issue. I'm curious as to how to use BOTH ECMs though. Besides tach and speedo, which the new ECM has outputs for, aren't the other gauges more mechanical and we can tap into the wiring?

AFAIK, if you want to use the EROD LS controller, you have to get different ABS reluctors. I really would rather keep my FX3 and C68 and DEFINITELY the ABS that I spent a lot of time and money fixing but the LS swaps are tempting too. OTOH, if I have to spend too much money, it might be better to sell what I got and get a C5. So say if you spend 20K on the swap, would you be better off with a C5? OTOH, if you spent $5000 to do it, sure.

Obviously, whatever you do with the electronics, you are going to swap the motor so whether it is a crate motor or whether you trust a junkyard motor is another story. I have friends that do not trust anything that didn't come in a crate or a rebuild shop. Another way is to get a cheap JY motor and when it dies, get whatever you want since the LS platform is going to be more modifiable than the L98 once you maxed it out.

pezter22

I'm in the middle of planning my LS swap for my '84.

I found these adjustable mounts from Dirty Dingo that look like they will work for me. They also sell a upper AC bracket as well.

http://www.dirtydingo.com/shop/produ...f7661502d5c70a

http://www.dirtydingo.com/shop/produ...oducts_id=1418

TurbineSurgine

I used these http://amzn.com/B00JU7LQ8Y on my 85 ls3 swap with zf6, the c beam did not have to be changed or modified. the only fitment issues is with the wiper motor and fuel rail are occupying the same space and the drivers side valve cover has a capped nipple that must be eliminated.

MrVette90l98mt

This is all good info, This is why i love this forum!

For the Quicktime bell- is the over all height and ball stud location the same as OEM bell? will an OEM fork fit? On second thought the slave mount that I mention will not be a direct fit but what if I had a fabricator to create something similar? I really don't want to buy a whole new clutch setup as my current SPEC clutch is still new with <10k mi and can hold up to 550 Lbs/ft torque. What pilot bearing to use?

Cool, engine mounts sound like they are sorted out. Corvette Central will be releasing their own engine mounts soon. I wonder why? Could they be different to make things more drop in friendly?

As far as keeping both ECM's-I was planning to splice the minimum needed signals to the old ECM to keep the sub systems happy (if needed). I know my A/C clutch will not engage unless the engine is running. I'm not sure if the BCM will go into a security lock out mode with no OEM ECM present.

Off topic a little but does anybody know if Jeg's or Summit have sales on create engines? Like a "Tax refund" themed sale or holiday 10% off everything sale soon?

TurbineSurgine

Do you have the factory service manuals, you have a 90 right? I think pretty much everything can be work around to eliminate the requirement of the factory ecm. I so happen to have the fsm manuals for a 90 model and looking at some schematics you can run the a/c clutch off the e38 (ls3) ecm x1 plug pin 63 -> c237 pin H. The selective ride control looks like it only shares a input signal from the speed sensor on the tailshaft of the gearbox, I don't believe the factory ecm needs to be connected to operate the src, you would wire these into the e38 x1 plug pins 71 and 72.
Here are the pinouts for the e38 ecm-- http://www.lt1swap.com/wiringharness.htm
If you don't have the factory fsm I would be happy to sell you mine