My buddy Jack was asking me if he built a high compression stroker with 12:1 and he sprayed 100 wet or dry what octane should he run, would straight 100 octane work with say 22 degrees of timing?

 

I dunno what kind of timing an LS1 motor will usually take, I'd figure with 4-5 degrees of retard from full advance (on motor) and 100 octane he should be plenty fine.

Don't forget plug heat range. <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Pro Stock John:
<strong> would straight 100 octane work with say 22 degrees of timing?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">With that much timing, your friend will most likely go <img border="0" alt="[kaboom]" title="" src="graemlins/gr_bomb.gif" /> Drop the timing at least in half.

 

I agree John....even the FI cars making 500rwhp on stock bottom ends are running 18-20 degrees of timing with zero KR.

My motor will be about 11:1 when it goes back in, and I plan on spraying eventually. I'd say with 12:1, you need to be fairly conservative at first. Try 20 degrees and see what happens, then work your way up. Only way to find out is trial and error.

 

ARE is my primary engine builder and they are reccomending that I run 18-19 degrees of timing to start with the new 12:1 setup and a 150 shot.

 

I would start out in the 18~19 degree range, then gradually build up until you do get some KR, then back it off 2 degrees. I say this assuming you will have forged pistons and be running race gas.

 

I errr I mean Jack has forged pistons (Ross) and will run straight 100 octane.

 

ls1290, why do you say that? Stock timing is let's say 28 degrees. I think 14 degrees of timing is too low.

I've been told to drop timing 2-3 degrees for every 100 shot of nitrous, so at say 200 shot we're thinking we'd run maybe 20-22 degrees of timing.