Another point worth noting, engine vacuum.
When the car was together before, the engine made 4" of vacuum. Not really knowing items such as ring seal, camshaft timing, and how much porting the original heads had received, is one of the reasons I elected to freshen the engine when switching to the aluminum heads. Another point worth making, is both the aluminum 842's and the iron 840's, each were converted to a 2.30 intake valve. Steve at AMS was impressed with the porting work on the iron 840's and noted that they were not all hogged out. I know when Jim Y. (A Stock) was in the engine 20 some years ago, he spent some good money on those heads (I have the receipt).
The rings and cylinders looked really good. All AMS did was hone and rering. The cam was checked for any wear, measured for lift and duration, and reinstalled at 106 degrees (as it had been previously) with a new timing chain and gear set.
On the dyno, idling at 1200 (where it had been idling previously) it now pulls 8" of vacuum. In short, that's how restrictive the stock exhaust system is on these cars. Over the summer, I finally had met John Karvonen (302mo) in person and saw his beautiful 67 L78 car. At the time, John just had header mufflers. Later on, John had gotten his Gardner system installed, and it changed the personality of the engine considerably. Mind you, that is in no disrespect to Gardner exhaust at all, it's just how inefficient the original design is. In hindsight, I probably should have changed the exhaust before diving in. I suspect the Camaro would have been silly.
On the last note, I have the original 396 short block at AMS as well. Steve is checking that over. Depending what is found, I may freshen that up. A while back, Eric Jackson had Bullet Cams grind up a duplicate of the stock 143 cam to some exacting specs. I had gotten one of them for the original motor, thinking I'd freshen it up one day in the future.
We'll see what happens.......it seems like I have been heaving money all over the place lately.
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