OK, well here's some info. From Jon Kaase
The engine is a 4.627" bore aluminum block, 4,375" stroke. makes 588". We traded for the block and crank, but they were new. It's a Bryant billet crank. It uses Oliver 6.8" rods and Diamond pistons. compression is 10.5 to 1. The boss heads and intake are our new stuff. both are as delivered, unported. They use 2.300 and 1.900 valves, steel Manley. The springs are 221443 Manley. (the same spring we supply with P-51 roller cam heads)
The cam we started with was a Comp, 273-280, 109*, .456 lobe lift with 1.75 rockers. This cam was not realistic for the street, it runs too rough at 2000-3500. It would make good peak power though. The second cam was the street roller (mech. roller). 251-251, 110*, .400 lobe. With lash and flex, net lift is around .660"
The first afternoon we made some max power type runs. It made 973HP right away, which was about right about where we thought it would be. I wanted to see 1000, but the weather was not going to cooperate, with terrible barometer and nonstop storms. Water was dripping off the manifold and carb. I put the Enginemasters 2" headers on and it was about the same until 6000, then lost about 30 peak.
The next day we changed to the street roller. It did really well, as the low speed was better, as well as the peak torque. It always made about 800 ft/lbs, no matter what cam or headers were on it. The smaller cam didn't have the peak HP numbers above 6000, but I would bet that it feels stronger in the car. It makes 885HP. It's real smooth from 1100 rpm, all the way to 7000.
I had to make a spacer/adapter for the crank pulley. The drive kit was made to use a long snout 460 type crank, where my crank uses a Cleveland snout and ATI balancer. Other than that, we installed the whole front drive setup in an hour. Nice stuff. As you can see from the photos, it fits in the car real well.
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