I will be putting together a stage 2 motor sometime in the near future. The heads are flowing 315,280. The cam is a 296-08H- 107 deg. 243/247@.050. It will be a 464 with forged pistons, stock rods with ARP bolts... your typical 464 short block. I plan to use an SPX manifold with an 850 Holley for now, and upgrade to fuel injection soon after. I will be using large tube full length headers. First question... can anyone guess what kind of power this engine will make? My guess is somewhere around 575Hp. second question... What block modifications will a motor like this absolutely need? I don't want to girdle it if I don't have to. I was thinking about using main studs and a Poston girdled pan. I don't plan to ever spin it over 6000 RPM. The goal is a fast (low 11's) but streetable car that will see a lot of track weekends.
Steve, if you aren't planning on reving over 6000, I'd run the Stage 1 alum heads. Stage 2's only pick you up over 6000, IME. Bruce
I think your Stg 2's are a good way to go. You can't go wrong with air flow. With that SPX, it likes a little more plentium volume and that 850 is small for your combination so If you could fit a 1" carb spacer on it that would help. I would definitely do the main studs and look at a halo girdle. Get a good balance job. If you haven't bought the pistons yet go to a litter higher $$ forged since it will take some stress away from the bottom end. The Seal Power and Hyper pistons are heavy. Thats my opinion....:TU:
Thanks, Rick. Pistons are forged 22cc dished from finishline motorsports. If I remember right, they are right around 680 grams... not the lightest, but not super heavy. I know that the carb is too small. I picked it up for a good price, and I will use it to get the car up and running. Once everything is tweeked and the motor is broken in, I'm going to go with fuel injection, so I'll replace the small carb with a bigger throttle body. I've got the main studs, and a good sfi flywheel and balancer. Is it necessary to internally balance, or do you mean a good external balance job? I don't plan to spin it up past 6000. I figured good heads were the best way to a fast street car, and would be a good investment. I'm not sure how a good flowing exhaust port wouldn't help power across the board.
A good external type balance should be fine. Internal balance is always a better way to go but its a money issue. You'll be no more than 6000 so I don't see it to be a problem. As long as down the road you don't plan on pushing the rpm's higher with the external balance. On the carb, a 1" spacer will help if you have the room but if its just to get you running for now I understand it will work.
