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Has anyone tried more timing(360-2 INDYS)???

Posted By: jb15

Has anyone tried more timing(360-2 INDYS)??? - 06/14/09 12:19 PM

seen in a post by Ryan,J ,that He found the Indy small block heads liked lots of timing(38-42deg,s) something like that. Wondering if anyone has tried this on the track with any results.
Jim.

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Posted By: mopar dave

Re: Has anyone tried more timing(360-2 INDYS)??? - 06/14/09 01:08 PM

i noticed that post also. i have the 360-1 heads and used to run 32* as the best on a previous dyno using 92 pump gas, but found on a dyno last week it liked 35* with ultra 94, picked up 15hp. i'll find out more on this when i get to the track.
Posted By: Quicktree

Re: Has anyone tried more timing(360-2 INDYS)??? - 06/14/09 01:16 PM

my 1s like a lot of timing.
Posted By: jb15

Re: Has anyone tried more timing(360-2 INDYS)??? - 06/14/09 11:34 PM

I've tryed as much as 36 degrees, but was just curious if anyone had tried higher with good results, as we don't get to play much here before eliminations. OOOh well ,thanks for the input.

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Posted By: RyanJ

Re: Has anyone tried more timing(360-2 INDYS)??? - 06/16/09 03:08 PM

All the stuff I've ran with the big timing has had the INDY CNC combustion chamber....Those #'s do NOT relate to any type of hand ported chamber as they can be any & all kind of shapes/sizes etc. It just seems the CNC chamber for whatever reason seems to make best power with alot of spark lead. There are alot of factors that go into what timing an engine likes, fuel, chamber design, piston design etc etc. But as generality they seem to like alot of timing, at least all ones I've ever dynoed have.
Posted By: a408swinger

Re: Has anyone tried more timing(360-2 INDYS)??? - 06/16/09 04:22 PM

Quote:

seen in a post by Ryan,J ,that He found the Indy small block heads liked lots of timing(38-42deg,s) something like that. Wondering if anyone has tried this on the track with any results.
Jim.



My old hand ported -1's made best power at around 33-34 degrees of timing. My CNC -1's seem to like 38-40*. Im guessing because they have a much larger chamber. Usually a more efficient chamber requires less timing so Im not sure why they like so much timing either but that seems to be the case with my heads also. My chambers are still 67cc's after being milled .030 and my old chambers were 57cc's.
Posted By: RyanJ

Re: Has anyone tried more timing(360-2 INDYS)??? - 06/16/09 06:11 PM

Quote:

Quote:

seen in a post by Ryan,J ,that He found the Indy small block heads liked lots of timing(38-42deg,s) something like that. Wondering if anyone has tried this on the track with any results.
Jim.



My old hand ported -1's made best power at around 33-34 degrees of timing. My CNC -1's seem to like 38-40*. Im guessing because they have a much larger chamber. Usually a more efficient chamber requires less timing so Im not sure why they like so much timing either but that seems to be the case with my heads also. My chambers are still 67cc's after being milled .030 and my old chambers were 57cc's.



It's more to do with the shape of chamber than raw size...Those CNC chambers generally wet flow & burn alot differently than a hand ported version of the cast ICH chamber. ie. most hand port jobs do not change the shape of the chamber as drastically as the CNC version is, so end up with 2 completely different shapes. It's a very efficient chamber, I've gotten to see burn patterns off of a bunch of used ICH CNC chambers & they always exhibit a nice burn, it's big part of why they make so much power.
Posted By: mopar dave

Re: Has anyone tried more timing(360-2 INDYS)??? - 06/16/09 06:55 PM

quicktree, what timing have you found to be best for your combo? i use a reverse dome piston at 0 deck and .039 quench. is yours simular?
Posted By: Quicktree

Re: Has anyone tried more timing(360-2 INDYS)??? - 06/16/09 07:50 PM

Quote:

quicktree, what timing have you found to be best for your combo? i use a reverse dome piston at 0 deck and .039 quench. is yours simular?



mine likes around 38-40 I have flat tops down in the hole just a tad. mine are hand ported by Dwayne.
Posted By: SB449VALIANT

Re: Has anyone tried more timing(360-2 INDYS)??? - 06/16/09 08:39 PM

im under the impression that the more eficient the combustion chamber the less time will need, might be complety wrong
Posted By: mopar dave

Re: Has anyone tried more timing(360-2 INDYS)??? - 06/16/09 08:57 PM

thanks quicktree. i have alittle better quench, so mine should be good where its at,35*. i might try 38* when i get to a track.
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