Frame Rate Discrepancy

[5_Liter_Eater]

If I am I reading the help file correct it says that E38 and E67 PCMs will maintain 40 frames per second for up to 28 bytes. The attached log (from my E38 '05 vette) has 20 bytes and when I calculate the frame rate (by scrolling through the charts) it's only 1/3 of that. Am I missing something?

[EC_Tune]

Yep, the E40 (05 Vette, SSR, Tblazer, GTO, 06 SSR, TBlazer, GTO) is slower than the E38 as far as data goes.

[5_Liter_Eater]

I don't know that I was thinking. For some reason I had it in my head when I posted this that I had an E38.... Guess I shoulda read my sig...

So I need to keep it at or under 14 bytes to get a bump. Damn E40's....

[EC_Tune]

Hahaha Yeah sometimes your sig comes in handy.

The E40 is still a bunch faster than the PCM in the LS1-LS6's. You should be fine with 24 bytes. How much data per second are you trying to get and what are you logging? Nuther words, whacha after?

[5_Liter_Eater]

I'm not that concerned about it actually. When I got confused I was stoked thinking I had 40 frames/sec, but as long as I keep it under 28 bytes I still have 10 which is fine I guess.

[EC_Tune]

Okey Dokey. How's the tuning coming along in general?

[5_Liter_Eater]

It was taking longer than I hoped to get the 2 bar SD dialed in. Even multiplying by 1/2 and overshooting. Some cells that got hit a lot were able to get down to +-1% but I wasn't happy with it and started to remember why I gave up trying to tune the E40 VE over a year ago. I started logging MAF Hz and flow and I was barely under both limits (coming closer to maxing out the Hz first) so last night I tried converting back to the stock OS. Within 2-3 iterations I had the curve nailed. Very close AFR error and the car felt much better and smoother.

I got to talking about MAFs with Joe Lynch on CF and I think I'm going to take a queue from him and install a bigger MAF to get more frequency range.

http://forums.corvetteforum.com/show....php?t=2069526

Here's my current if you have some time to kill.

[EC_Tune]

Yeah that MAF is basically the 08 LS3 MAF in a custom housing. VaraRam supplies that style housing for their C6 Z06 & 08+ LS3 CAI's. Might want to give them a call about the housing. I can get you a deal on the LS3 MAF & pigtail. Let me know...

[Frost]

I am working on the both pigtails and making a plug and play harness for the new style MAF. The harnesses (for both ls1 and ls2 applications) will support the IAT in the MAF in one form and another will break the IAT out for relocation for FI, etc.

[EC_Tune]

Frost, while you're on it, how about making a harness for the 2.5 bar MAP/IAT combo from the Cobalt/Ion Redline.

[Frost]

Frost, while you're on it, how about making a harness for the 2.5 bar MAP/IAT combo from the Cobalt/Ion Redline.

Hmmm, Doug I'm not sure exactly what we are talking about here, but what would you need on the ends?

I have made a MAP harness that lets you plug the 3-bar (12223861 - 16040749) and 2 bar (12247571 - 16040609) MAP sensors directly into the LS1/6 harness and gives you a little extra length to boot.

[EC_Tune]

I was thinking about the E40, E38, and E67 PCM's. So it would have to plug into the factory MAF harness to pickup the IAT and the factory MAP sensor then combine the MAP & IAT to plug into the MAP/IAT of the Cobalt 2.5 Bar sensor.

[Frost]

I'm looking into it for you now

[EC_Tune]

Thanks Steve!