I agree, my build worked out to 10.71 compression. I can't get more than 26 degrees on 93 octane. I can go to 32 with a mix of race fuel. Do not let it ping !! I can't stand that noise.:blast:
I don't think it will effect it that much. Trying it costs nothing. Just because someone else's motor likes 32, or 34, or 36*, doesn't mean yours will. Reduce it down to 30, then 28* if you have to. Get it to stop pinging first. If it was me, I'd just add some race gas to it, which is what I used to do.
I did just buy a big Race jug for high octane gas that i can get at Atco, but was curious if any of you have used the stuff in the attached link? http://www.batterystuff.com/products/OScase.html
Looks OK, but when they say boosts octane in points, that means 1/10 of a number to me, so 2 points means a boost of 93 to 93.2. How much do you need to use? Probably quite a bit. I haven't come across anything as economical as race gas. Adding 2 gallons of 110 to 18 gallons of 93 gets you 94.7 octane. 3 gallons 110 to 17 gallons 93 gets you 95.5 octane. It's a simple average.
I think you need to confirm the engine temp. Do you have an infrared gun? Does the upper radiator hose get hot? What type of pulleys? Backing your timing off a couple of degrees won't effect the engine temp. If your engine temp is indeed correct, I would start there.
I don't have an infared gun. I am using a brand new Autometer temp gage. Upper radiator hose does get hot. i am using March underdrive crank pulley, TA perfomance billet smaller water pump pulley.
Use the search key for the histories of overheating problems experienced by members using the same March underdrives.
Just the crank is underdrive. the water pump is stock size Aren't there some using with no heating issues??? I didn't use the March water pimp pulley case it WAY bigger than stock
sounds like they did what i have now, smaller crank pulley with stock size water pump pulley (ditch the large water pump March pulley) and that worked, if i'm reading that correct.
You had the car out before this started and it ran fine, no pinging, etc. You took it out and ran it hard and it started with the following symptoms: 1) Getting hot at most engine speeds 2) Idles higher than before this problem started 3) Pings under load when it was fine prior to this, with no changes to the ignition timing. 4) All the plugs have the same color. With all due respect to the Wizard, it sounds like to me you need to start checking for a vacuum leak. Start the engine and let it idle. Restrict the air going into the carb by placing your hand over the top of the carb itself until you feel the suction from the engine. If the idle smooths out, voila, you definitely have a leak. My Chevy pick-up did something pretty close to what you are experiencing. It was about 300 miles after I put a spacer under the TBI unit. It came with thin paper gaskets. Turned out, one of those gaskets failed and allowed a leak. It started to ping, idled too high and ran hot. Replaced both gaskets (after a BUNCH of playing around, trying this and that) and it instantly cured the problems.
I totally agree, so much so, that I have a vacuum gauge permanently installed in my GS. I know what my normal vacuum reading is, and always check it.
Kick, I have a similar combo and I am worried about the temp first. EVERY time I have had my motor apart & back together my temp would do the same thing on initial start up. It was(for me) an air pocket somewhere in the cooling system. I would squeeze the upper rad hose with my hands a few times & then the pocket would excape & temp would go back down to a normal level. I have 9.8-1 compression & run pump 93 gas @ 34deg total timing. Never a problem. I am not too familiar with MSD stuff. I run GM HEI with a crane adjustible vac advance. My plugs look similar to yours, but I have no pinging & with my alum rad, cant get the temp over 190. Do a visual check of your harmonic balancer, mine just broke/separated the outer ring. I would just be happier if the temp was at a comfortable level before I drove it to Yardley's. Check vacuum leak also. Good point.
I use a 180F thermostat (regular old Napa one), stock fan clutch, fan and shroud. The key for me was the aluminum radiator. Adding TA's pulleys this year made no difference, which is good.
