I just heard about this website the other day and after reading through some of the posts I'm impressed with the amount of knowledgable guys that frequent this site. I hope I won't get booted for not having a Chevelle but I could really use some of you guys' expertise.

I'm building a 355 to put in my '65 Nova and I'm trying to figure out if it'll run ok on pump-gas. I've plugged the figures into Pat Kelley's calculator and it comes up with a DCR of 8.19:1 and a SCR of 10.2:1 with a steel shim gasket. The quench sits at .040. I live at a 7000ft DA and I'm hoping this engine will run on 91 octane fuel, especially since it's a 2900lb car.

EA3.3 says that at my altitude the DCR ends up being 7.66 which sounds like it should work. I know DCR isn't everything (read that in some older posts) but until I get the car together I won't know how it handles 91 octane. I'd rather change something now while the engine's being machined than after I put everything together. Combo is below.

.030 over 350
Cast flattop pistons
Victor Jr.
Ported Sportsman IIs (263/214@.500)
1 3/4" Super Comps
BTE 3500 stall
Edelbrock 750 carb
Isky 274-Mega (226/226@50, .523 lift, 108 LSA)

Any thoughts/advice?

I think you'll have a good combination there, with the dcr you have 91 octane shouldn't be a problem IMO. The quench or squish should be right on at .040. In fact I bet it will run on 87 in a pinch if you pull back a couple degrees of spark timing. Many things factor into whether the combo will work on a certain octane. Make sure you take off any sharp edges or rough spots in the combustion chamber, polishing the exhaust valves also loweres their running temperature/ability to absorb heat. Spark plug selection also is critical if running on the edge. Your car is light also which helps. I think it'll be just fine.

Hey badbob, which spark plugs would you recommend? I have had good luck with Autolites but I've never tried anything else except for $plitfires.

You'll be fine on 91 man. Like baddbob said, if you were to kick the timing down a little, you could probably pull off 87. 93 is only .20 more than 87 anyway....why worry?

Best of luck
-Ben

P.S. 65 Nova's are kick butt! I've got a buddy building up a 65 or 66 (forgot) nova right now. Plans for engine will put it between 1,000 - 1,200 hp, depending on which combo. lol He's a crazy guy! Have fun

I'm glad you guys think it will be ok.

71chevy0192- I wish we could get 93 around here but the best I can get is 91. Sounds like your buddy is shooting for 8-second territory. Should be a wild ride. Mine won't be anywhere near that powerful. I've got a little four-door that should be a fun sleeper.