What are your thoughts on this AFR
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What are your thoughts on this AFR
I've taken my car to the dyno a few times (tune it myself) and it always seems to make the most power at around an 11.8 afr. It is naturally aspirated with a 224/236 574/572 111 lsa cam. Do you guys find this strange. We're talking a significant gain from an afr in the low 12s to 11.8 40-50 hp. Anybody have any thoughts. I always hear and read people set the car at like 12.7-13.1. I wouldn't make any power at that range.
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timing seems to have little effect on the car from 33-39 degrees only like a 3-5 hp difference. when I play with the afr i see the biggest jumps. i gotta check what my WOT timing is Im pretty sure its at 33. It looks like no matter what the timing it likes to be real rich. could there be a problem somewhere?
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I have read some old Datamaster files for my old LT1 and it took alot of time, after all the other factors were considered. It was kinda scary at least compare to LSx. But that is due to the fact that LS1's have such good cyl head tech and the burn rates are superior.
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28 seems a little low for the lt1 most guys run 35-37 at WOT. it can't hurt to try though.
the first dyno session i did timing only and the car had only 3-5 hp differences. however on 1 pull the afr with no explanation dropped to 11.8 making 452 hp about 80 more than all the other runs. on all the other runs the afr was pretty consistant with timing changing. When I went another day I was going to tune strcitly the afr at the timing which made the most power which was 33. All afr changes had minimal affect. For some reason I couldn't get the car back down to 11.8 but it hink this had to do with my CAT overtemp tables screwing me up.
I checked dyno logs of my old setup and it confirmed that at an afr of 11.8 i made the most power of 396 hp which was 40 more than all the other runs.
I find it real weird that ~11.8 seems to be some magical number for my car.
Has anyone ever seen something like this before?
the first dyno session i did timing only and the car had only 3-5 hp differences. however on 1 pull the afr with no explanation dropped to 11.8 making 452 hp about 80 more than all the other runs. on all the other runs the afr was pretty consistant with timing changing. When I went another day I was going to tune strcitly the afr at the timing which made the most power which was 33. All afr changes had minimal affect. For some reason I couldn't get the car back down to 11.8 but it hink this had to do with my CAT overtemp tables screwing me up.
I checked dyno logs of my old setup and it confirmed that at an afr of 11.8 i made the most power of 396 hp which was 40 more than all the other runs.
I find it real weird that ~11.8 seems to be some magical number for my car.
Has anyone ever seen something like this before?