How much extra timing to pull for every 10 degrees temperature increase
04-20-2013, 08:55 PM
#1
How much extra timing to pull for every 10 degrees temperature increase Going to the track tomorrow and it will only be 45 degrees. I'm sure that is good for horsepower but I'm looking for a good rule of thumb for timing. At 65 degrees on a 200 shot I am pulling 10 degrees from base of 25. I will be pulling plugs ..just looking for a starting point. Appreciate some voice of experience on this one.
Last edited by CanadianEh!; 04-21-2013 at 07:27 PM.
04-21-2013, 07:35 PM
#2
Temperature does make a difference! Decided to pull 2 extra degrees (25-12=13 degrees total) on 200 shot due to the cold weather (41degrees fahrenheit). Still melted #5 plug on the same 78/36 combo I ran no issues last year in warmer weather (75-80 fahrenheit). Added 5 pounds to the dedicated and plug looked ok for timing but due to tire issues could not make any aditional runs. Just a FYI for less experienced nitrous users to consider the weather changes to your tune!
Last edited by CanadianEh!; 04-27-2013 at 07:10 AM.
04-22-2013, 07:02 AM
#5
#5 is my hot plug. The rest of the plugs all show less timing mark. I'm considering running a #10 plug in that hole. I have been tuning off #5 which I feel is more conservative and gives me more of a safety margin. Running Sunoco 110 in the dedicated at 50 psi and a mix of 94/110 in the main tank. I suppose I could also have the injectors Flow tested and put the highest flowing one for #5.....
04-22-2013, 09:56 AM
#6
Strange.. I'm aware you ran in cold weather and every setup is different, but with your setup, 13* is pretty low timing for only a 78 jet. You sure the #5 injector is ok? 
You might wanna do a compression or leakdown test in that cylinder.
You might wanna do a compression or leakdown test in that cylinder.
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04-22-2013, 06:15 PM
#8
Timing Pulled Hear you guys about the timing pulled but I am targeting 13:1 A/F on the Bottle so my tuning window is quite narrow. I have found I am running the same times on the 200 shot as I used to make on the 250 shot when I was running a richer tune. Still trying to find the sweet spot and keep up with weather changes and such. Some smart people on this forum have said that it's too much timing that hurts motors not running too lean (to a point).
04-23-2013, 10:06 AM
#9
It was definitely not too much timing. i think you needed to put some fuel in it. We have run ours in 35 degree temps on an .088/.044 with 15 degrees and made 6-8 passes that night and plugs looked fine. Could have pulled probably 2 steps out of fuel but played it safe in the cold air.
04-23-2013, 11:47 AM
#10
[QUOTE=Killer5.3;17340723]It was definitely not too much timing. i think you needed to put some fuel in it. We have run ours in 35 degree temps on an .088/.044 with 15 degrees and made 6-8 passes that night and plugs looked fine. Could have pulled probably 2 steps out of fuel but played it safe in the cold air.[/QUOTE
Thanks for the feedback and you are right it did need more fuel. The interesting thing is when I ran my 92/92 FAST set-up I was jetting 78/42 running consistent 10.50s. When I swapped to the 102/102 set-up with 100mm Maf it only wanted a 36 fuel jet and ran the same times. Don't know why that would be - perhaps someone has some thoughts. In any case swapped to a 3.73 gear this year so I can run a 28 inch tire - picked up 4/10ths on the n/a pass! On the nitrous passes was twisting and forcing the rear passenger side fender skirt into the tire so could not get any passes before doing some more trimming and adjustments. Always lots to learn but looking forward to some good times this year! Thanks to everyone for the feedback!
Thanks for the feedback and you are right it did need more fuel. The interesting thing is when I ran my 92/92 FAST set-up I was jetting 78/42 running consistent 10.50s. When I swapped to the 102/102 set-up with 100mm Maf it only wanted a 36 fuel jet and ran the same times. Don't know why that would be - perhaps someone has some thoughts. In any case swapped to a 3.73 gear this year so I can run a 28 inch tire - picked up 4/10ths on the n/a pass! On the nitrous passes was twisting and forcing the rear passenger side fender skirt into the tire so could not get any passes before doing some more trimming and adjustments. Always lots to learn but looking forward to some good times this year! Thanks to everyone for the feedback!
04-23-2013, 11:52 AM
#11
[QUOTE=CanadianEh!;17341005] Did your NA tune change?
It was definitely not too much timing. i think you needed to put some fuel in it. We have run ours in 35 degree temps on an .088/.044 with 15 degrees and made 6-8 passes that night and plugs looked fine. Could have pulled probably 2 steps out of fuel but played it safe in the cold air.[/QUOTE
Thanks for the feedback and you are right it did need more fuel. The interesting thing is when I ran my 92/92 FAST set-up I was jetting 78/42 running consistent 10.50s. When I swapped to the 102/102 set-up with 100mm Maf it only wanted a 36 fuel jet and ran the same times. Don't know why that would be - perhaps someone has some thoughts. In any case swapped to a 3.73 gear this year so I can run a 28 inch tire - picked up 4/10ths on the n/a pass! On the nitrous passes was twisting and forcing the rear passenger side fender skirt into the tire so could not get any passes before doing some more trimming and adjustments. Always lots to learn but looking forward to some good times this year! Thanks to everyone for the feedback!
Thanks for the feedback and you are right it did need more fuel. The interesting thing is when I ran my 92/92 FAST set-up I was jetting 78/42 running consistent 10.50s. When I swapped to the 102/102 set-up with 100mm Maf it only wanted a 36 fuel jet and ran the same times. Don't know why that would be - perhaps someone has some thoughts. In any case swapped to a 3.73 gear this year so I can run a 28 inch tire - picked up 4/10ths on the n/a pass! On the nitrous passes was twisting and forcing the rear passenger side fender skirt into the tire so could not get any passes before doing some more trimming and adjustments. Always lots to learn but looking forward to some good times this year! Thanks to everyone for the feedback!
04-24-2013, 05:56 PM
#17
Interesting thoughts about the timing. Tuner told me timing was 25 degrees at WOT but something isn't adding up for sure. I keep pulling what I think is conservative timing....using my Timing Tuner (validated it is working) and I'm still melting plugs. On the run using 78/36 jets, pulling 12 degrees, with 46llbs in dedicated (with 110), 50/50 mix (110/94) in main tank, it melted the strap on #3, 5 and 7. The rest of the plugs showed signs of just being on the edge of melting. I added 5 psi to the dedicated and pulled #5 on the next run and it looked ok but had to drive it down the return road due to tire issue. I can only pull maximum of 12 degrees using the Timing Tuner but have a new Lingenfelter 2 step that will allow me to pull 15 degrees. Next opportunity I'm going to start at 78/36, 50 psi in dedicated and 12 degrees pulled, pull plugs and take it from there. Plugs will tell the story!
Last edited by CanadianEh!; 04-27-2013 at 07:14 AM.