Make sure you ck all the fluids first.
I look forward to the video.

 

Anxiously awaiting your results!

Please let me know if it works out.

 

Here's a lame rear bumper video. The motor needs a bunch of tuning and the Open headers are limiting time out of the garage and thus tuning time. I'm working on getting the shop scheduled to have the exhaust made soon.

Note, no cats, emissions related or real, were harmed in the making of this video...

http://www.eecis.udel.edu/~davis/z28...y/L99Vette.mov

 

poor cat.. sounds like you are getting close. GJ

 

Hey it's running! Awesome! Very excited for you. Sounds rough, but I think that's expected without a tune, no? Do you have a WBO2? Keep up the good work - getting it running is the first step to getting it running right!

 

Still waiting for shop time to have the exhaust system made. I have the idle tune working, still tons of tuning to do once I can it out on the road. Trying to get it road worthy to make the Ocean City, MD Corvette Weekend in October.


Video clip with open headers, idling, ECM Scanning and dash tach, and some exhaust temps taken soon after startup.

 

Congratulations! I wish I could see what was on the HPT screen. Maybe you could take a screenshot next time. Is the tach right? If so, wow that is a low Idle speed - 500rpm? What tuning tools do you have?

Very happy for you. Keep it up!

 

YouTube really cuts the quality down, you can read the HPT screen in the raw video.

Tach is 400-500rpm low, actual idle was 900-1000 (tuned up because of the open headers). I was actually trying a 500ohm pull up in this test to see if it got better, because the 1K pull up read the same 400-500 lower.

I do pretty well just tuning using HPT and the stock O2s. For fine tuning, I have a zeitronix ZT2 WB-O2 in my camaro that I can pull out and tune another vehicle, and I picked up a barely used PLX Devices WB-O2 that I need to get a cable for. Probably leave the PLX installed in the vette if it works out.

 

VSS E38 hack didn't work. (still with open headers..)


I found one more setting in HPTuners to try, but haven't had a chance to test. I know the VSS is working because I have it wired to the C4 ECM/CCM and the digital display works. (Just way out of spec. Still has the stock 4000ppm while the T56 is putting out around 45000ppm)

 

you aren''t trying to share the vss with both ecm's are you ?

 

Sure am.. That's been one of the major parts of the swap, wiring/adapting sensors and signals between the 2 ECMs.

 

on my vet,i fed the vss to the new ecm and the output to the speedo. it works and hptuners can then be used to match speedo to gps for accuracy. ecm's dont like to share inputs.

 

"What pins on the E38 ECM did you use to feed the VSS and output to the speedo ? "

I tapped into the wire going to X1-71 for my VSS signal. In my case that is the TOS signal coming from the 6L80E. My car is not running yet so I don't know for sure that will work.

 

Thanks, I know what the pins are, actually X1-71 and X1-72 for the Discrete VSS without using a TCM. My point was that the GenIV ECM isn't the same as the GenIII setups that most swaps use and assume are the same.

 

Have you tried running the VSS as a dedicated into the E38 without the older ECM in play? Might be worth a shot - I agree with you it isn't a blanket statement, but may not be too hard to test just by disconnecting the old ECM.

Is there something special about the VSS used in the newer TR6060s compared to the T56? They do use the same ECM between the LS3 and L99 gen 5 Camaros right? Maybe having no communication with the tranny is upsetting things. Please keep us posted - eventually I'll run into the same issues.

 

Nope, not yet.. It was the first time the car ever moved under it's own power since I've had it almost 2 years. The neighbors' appreciate me not testing it a lot with open headers.. I have lots more tests to run, just reporting that it didn't work on the maiden voyage.. I'm positive I can and will get it working and it has been done already by others using the same setup.

 

Congrats on gettin her running! Yeah your gonna have some fun with that tune all right

Keep your eye on the throttle position mine was rolling back to 50% at about 20mph for yet another unknown reason

 

Nice build!
Thanks for sharing.

Mike

 

Well I'm eating Crow tonight, with a side of humble pie.. After doing a couple more OS tweaks, and grounding the P/N pin of the E38 PCM with no success, I pulled the VSS pins going to the Factory C4 ECM and the E38 started picking up a good VSS MPH signal. (Although I've split the VSS signal before, the C4 has the VSS feeding the ECM, the CCM, ABS, ASR, and FX3 shock controllers and hindsight is always 20/20)

So I'll have to dig back into the harnesses and schematic to play around with back feeding the C4 ECM (factory dash speedo) from the E38 PCM VSS output signal.

Note that I never had the 158mph reading in the E38 scanner as others did, my mph always read 0mph. I will try some other tests since I have to be in the harness again anyway, to try and get mine to read 158mph now that I know it works otherwise..

Finally, My tach now reads correctly too. I was following the post on HPT forums and missed the part about the poster putting his autometer in 4cyl mode and halving the RPM resolution (15/15) in the tune. Since my factory tach is in 8cyl mode, I doubled the resolution (7/7) and it now reads within 5% of what the Scanner tells me..

 

Hate to say it but. Lots of fun with these swaps.... Exacting is not precise enough


But with the methodology you employed thus far, You'll bring her home.

Carry on