Spark Timing - Page 2

Jeff Lee · 03-08-2011, 07:21 PM

Quote:

Originally Posted by Chris Hill

Art, what did the turbo cars like for timing?

My AF/S Shelby w/ VP116 & 25+ PSI boost liked 38-40 degrees total!

Billy Nees · 03-09-2011, 09:53 AM

That's because you were trying to use VP-116 and 25. Burns too slow and kills your EGTs and boost.

art leong · 03-09-2011, 10:42 AM

Quote:

Originally Posted by Billy Nees

That's because you were trying to use VP-116 and 25. Burns too slow and kills your EGTs and boost.

I actually ran quicker with pump gas. For nhra races I used the cheapest acceptable fuel I could get.
EGT's were 1800 at the finish line on the best runs.

Jeff Lee · 03-09-2011, 05:09 PM

This was when dialing in with a lap-top was "exotic" back in the dinosaur age of the mid '90's. I ran it rich with over sized injector's after melting three heads and knocking the crowns off three sets of factory pistons. Once I figured rich was not fast but safe, I never had a problem again. I always figured a sharper tuner than I could get it into the 12's. It took about 10 years for anybody to top my 13.26 record so it must not have been all bad!

art leong · 03-09-2011, 06:10 PM

Quote:

Originally Posted by Jeff Lee

This was when dialing in with a lap-top was "exotic" back in the dinosaur age of the mid '90's. I ran it rich with over sized injector's after melting three heads and knocking the crowns off three sets of factory pistons. Once I figured rich was not fast but safe, I never had a problem again. I always figured a sharper tuner than I could get it into the 12's. It took about 10 years for anybody to top my 13.26 record so it must not have been all bad!

Jeff the trick was to use pistons with over 100,000 miles on them. They are coated with carbon. I never had any tuning, just fuel pressure. My turbo wouldn't put out more than 18 pounds in the best conditions, but it was the small mitsubishi not the garret.
Ran a 13.46 with the Spirit on pump gas. On a mineshart day at Cecil County.

Mart Jeltema · 03-10-2011, 05:11 PM

This is a loaded question. BST differs from the dyno to race track in many cases. On our open chamber 10:1 engines we run anywhere from 42-46 degrees. BSFC numbers will vary with BARO (CALT) etc. It's a at the track tuning.

MJ

03-09-2011, 09:53 AM	#12
Billy Nees VIP Member Join Date: Oct 2002 Location: On a hilltop in Pa. Posts: 4,504 Likes: 3,606 Liked 7,807 Times in 1,748 Posts	Re: Spark Timing That's because you were trying to use VP-116 and 25. Burns too slow and kills your EGTs and boost. __________________ Billy Nees 1188 STK, SS I'm not spending 100K to win 2K

03-09-2011, 05:09 PM	#14
Jeff Lee VIP Member Join Date: Jul 2007 Location: Anthem, Arizona Posts: 2,766 Likes: 0 Liked 3 Times in 3 Posts	Re: Spark Timing This was when dialing in with a lap-top was "exotic" back in the dinosaur age of the mid '90's. I ran it rich with over sized injector's after melting three heads and knocking the crowns off three sets of factory pistons. Once I figured rich was not fast but safe, I never had a problem again. I always figured a sharper tuner than I could get it into the 12's. It took about 10 years for anybody to top my 13.26 record so it must not have been all bad! __________________ Jeff Lee 7494 D/S '70 AMX

03-10-2011, 05:11 PM	#16
Mart Jeltema Junior Member Join Date: Feb 2007 Posts: 37 Likes: 0 Liked 10 Times in 2 Posts	Re: Spark Timing This is a loaded question. BST differs from the dyno to race track in many cases. On our open chamber 10:1 engines we run anywhere from 42-46 degrees. BSFC numbers will vary with BARO (CALT) etc. It's a at the track tuning. MJ