I've got my head milled .050" and I am wondering if pumping mid-grade over regular-grade would give any benefit because of the increased compression. Is .050" enough to have it be worthwhile to run mid, or not? Thanks for any help.
There are too many variables to give a simple yes or no answer. Examples of the variables are altitude, engine maintenance, and load (weight). Second FT's advice, you'll need to tune it to your conditions. See if this helps, section 6.13: http://www.faqs.org/faqs/autos/gasoline-faq/part3/ Also, somewhere in there I picked up a rule of thumb that 1* of additional ignition advance or retard moves the octane requirement 1 point up or down. So if you move from 10* initial to, for example, 14*, add 4 points to the engine's octane need. Section 7.4. Good luck
Cool, thanks for the help guys. Funny story, my timing cover doesn't have any timing marks on it, so that makes it kinda hard to adjust my ignition timing. Don't ask me why they're not there, they just aern't.
running a higher octane gas isn't going to give you any more power by itself. All a higher octane rating dose, is it resists detination better then the lower octane fuel. Granted, a higher octane gas will allow you to run more timing, which means more power, but we are talking maybe 5hp, and alot more expensive fuel. I would think that you shouldn't be able to get by on 87, considering that you had the head milled, but if you can once you get the timing dialed in, then dont bother buying expensive gas.
