spark table tuning questions..
Thread Starter
Race Director
Joined: Nov 2000
Posts: 17,103
Likes: 39
From: stop the fun suckers
spark table tuning questions..
Whats the best way to approach tuning the spark table? I'm using a stock LT1 table now.. however, I am running 10.8:1 compression now with a cam that is similar to a hotcam.. I run 93 only..
thanks.
thanks.
Melting Slicks
Joined: May 1999
Posts: 2,037
Likes: 0
From: Sarasota FL
Re: spark table tuning questions.. (BluByU)
What car? MAF or MAP?
My extremely simplified version - eliminate knocks by retarding timing, get fueling on target, advance timing a little, lather, rinse, repeat.
Disclaimer: every car is different, many tuning parameters interact, you should work on the whole operating range - idle, part throttle, WOT
My extremely simplified version - eliminate knocks by retarding timing, get fueling on target, advance timing a little, lather, rinse, repeat.
Disclaimer: every car is different, many tuning parameters interact, you should work on the whole operating range - idle, part throttle, WOT
Pro
Joined: Jun 2001
Posts: 708
Likes: 0
From: Florida
Re: spark table tuning questions.. (STL94LT1)
STL94LT1,
I'd love a copy of that spreadsheet too :yesnod:
e-mail: Donovanhalen@cs.com
'95 LT1 (in a '76) 1-5/8" lt headers, 1.6 RR, MAF, "mild" porting...nothing too fancy
Thanks :cheers:
Dr.
[Modified by DR'76, 12:02 AM 12/21/2003]
I'd love a copy of that spreadsheet too :yesnod:
e-mail: Donovanhalen@cs.com
'95 LT1 (in a '76) 1-5/8" lt headers, 1.6 RR, MAF, "mild" porting...nothing too fancy
Thanks :cheers:
Dr.
[Modified by DR'76, 12:02 AM 12/21/2003]
Instructor
Joined: Sep 2003
Posts: 109
Likes: 0
From: Ft. Lauderdale FL
Re: spark table tuning questions.. (DR'76)
Staying up late into the Wee hours of the morning surfing the web are we Dr?
Should be locked away in that garage of yours finishing up your ride while the weather is still cool. Once it warms up, you might not want to :D
Should be locked away in that garage of yours finishing up your ride while the weather is still cool. Once it warms up, you might not want to :D
Instructor
Joined: Sep 2003
Posts: 109
Likes: 0
From: Ft. Lauderdale FL
Re: spark table tuning questions.. (BluByU)
BluByU-
I have not messed with LT1 engines, but alot of research has revealed conventional smallblocks like conservative overall timing with an aggressive timing curve- like, all in by 2200-2400 rpm in WOT. More efficient combustion chambers like a VORTEC or your fast-burn(?) heads will require less advance because the chamber is more conducive to combustion (no obstructions to the flame-front). For part throttle, the only way to gauge if your timing change is accomplishing anything is by looking at your TPS voltage and possibly a vacuum gauge. If you get the same mph over the same stretch of road, but with less throttle (lower TPS voltage) and higher vacuum , your timing change is for the better.
Always start with conservative total advance and work up to max timing, never start with spark knock and pull timing out- too risky for the motor.
Tuning a spark table can be a real PITA, but the results can be eye opening. :eek:
Good luck.
I have not messed with LT1 engines, but alot of research has revealed conventional smallblocks like conservative overall timing with an aggressive timing curve- like, all in by 2200-2400 rpm in WOT. More efficient combustion chambers like a VORTEC or your fast-burn(?) heads will require less advance because the chamber is more conducive to combustion (no obstructions to the flame-front). For part throttle, the only way to gauge if your timing change is accomplishing anything is by looking at your TPS voltage and possibly a vacuum gauge. If you get the same mph over the same stretch of road, but with less throttle (lower TPS voltage) and higher vacuum , your timing change is for the better.
Always start with conservative total advance and work up to max timing, never start with spark knock and pull timing out- too risky for the motor.
Tuning a spark table can be a real PITA, but the results can be eye opening. :eek:
Good luck.
