Went to the track! 15 psi and 93 octane Citgo gas!

[nitrorocket]

Well, I finally went to the drag strip with my Twin Turbo Chevelle. I went 10.50@ 136.34. I was hopeing to go faster, but the track was way too busy to make any passes. This was on 315/35/17 drag radials and Citgo 93 octane @ 15 psi. I wish I had more time to dial in the suspension. I only hooked a 1.80 second 60'. Last year I did a 1.60 60', but the car did not have turbos. A few more launches and I would have pulled off a high 9 second run. Oh well, always next year!

I wish I would have had time to tune. I was at 11.5:1 afr and 15.5 degrees of timing. I CANNOT GET MY TIMING TO STAY AT TABLE VALUE's!! I am commanding 18 degrees and only getting 15.5???? Anyone know what the deal is? :bang:

All in all, not bad for a pumpgas car with a raceweight of about 3840 lbs.

[foff667]

congrats on the times...theres probably some adder/multiplyer tables coming into play.

[Blacky]

Got a video?
Paul

[Blacky]

I wish I would have had time to tune. I was at 11.5:1 afr and 15.5 degrees of timing. I CANNOT GET MY TIMING TO STAY AT TABLE VALUE's!! I am commanding 18 degrees and only getting 15.5???? Anyone know what the deal is? :bang:

Have you logged the GM.EST_xxx_DMA PIDs? They shuol dshow you all the partial spark components that are added to obtain the final "run spark". You can usually see which table is responsible for pulling the spark.

Regards
Paul

[nitrorocket]

No I have not logged those tables. Just the SAE.SPARKADV

I do not have a video. I am also having hot intake temp problems. My turbos are mounted behind the radiator and are sucking 200 degree air. At the end of my pass I was seeing 138 degrees!

What tables would probably be the timing reduction culprit?

[GMPX]

First up, nice times for the first outing, I'd be interested to hear some reactions of people that looked at the engine bay.

Nasty intake temps for sure, better check table {B5911}, might be losing it in there, would be better to get the lower intake temps though!.

Cheers,
Ross

EDIT - Metric mind thinking here, you were talking 138degF, not 138degC. :oops:

[nitrorocket]

According to that table, It would have pulled about 2.5 degrees of timing at 138 degree intake temps.

My biggest problem is my converter. I need to buy a different one. I am pushing through mine. I get 5500 rpm off the trans brake! And my data log shows the car stayed at 6600 rpm the entire pass and went through the traps at 6900 rpm at only 137 mph!! I have a 3.42 gear with a 26" tall tire! That doesn't sound right does it!

With the custom O.S. 3 bar, should I have high and low timing tables the same? Will the pcm still have the ability to lower timing for knock?

Also, was'nt there some talk about making a IAT VE correction table instead of the engine temp table? I sure could use that.

I want to thank everyone for your help. It has been quite a learning curve with the setup I have!!

[GMPX]

According to that table, It would have pulled about 2.5 degrees of timing at 138 degree intake temps.

As Paul said, you should log the spark PID's to see which one is the offender.

With the custom O.S. 3 bar, should I have high and low timing tables the same? Will the pcm still have the ability to lower timing for knock?

One of the advantages is that you get the twin maps, don't make them the same, it is safe (and better) to pull say 5 - 7 degrees out of the low octane table above say 0.40g/cyl. Just make sure {A0000} is set to disable and {A0002} is set to 100.

Also, was'nt there some talk about making a IAT VE correction table instead of the engine temp table? I sure could use that.

Yes, just need your O.S number.

I want to thank everyone for your help. It has been quite a learning curve with the setup I have!!

No problem, it's good to see how far you have progressed, certainly a brave man to take the challenge tuning that motor on your first use of EFILive.

Cheers,
Ross

[nitrorocket]

Thanks for all the info.

And to think everyone heavily doubted my abilities because of all my stupid questions!

I will have to make sure my low octane table is setup that way. I only have it 1 degree lower.

My O.S. # is 02020003. Is that the best one?

[mistermike]

No problem, it's good to see how far you have progressed, certainly a brave man to take the challenge tuning that motor on your first use of EFILive.

Cheers,
Ross

Brass balls, I'd say. Good job, Nitro!