73 Mike
I'll drive it someday
It's time to get started on my next engine. For those of you that don't remember, I had a minor mishap with my last one that resulted in me replacing it with a cheap, used crate engine that has less power than my old 72 Chevy Vega with a straight 4. Kept me on the road for the summer at least.
I plan on using the crank (3.75 stroke and already magnifluxed) and rods from the last build. I did replace the one that was slightly bent :bounce:
I also plan on using the iron head (72 cc chamber and 200 cc runner) and am looking for a static CR around 9.75:1. I'll likely switch from the solid, roller lifter set up that I used to a hydraulic roller, but that discusion is for another day.
I was able to pick up a nice Motown block that needed boring. Unfortunately, it came with installed o-rings that had to be decked off because the placement didn't allow for an overbore. The net result is that I now have a deck height that is 27 thousanths below 9.8 inches. I picked up a cheap piston from Summit and verified the deck is even accross all eight cylinders.
I think that I have three realistic options for the pistons:
1) Purchase a set of custom pistons with a lower compression height so that I have a zero deck. This is probably the most expensive but not by all that much. I'd also have to machine the intake, but it's only money :crap:
2) I found a set of Felpro head gaskets with a compressed thickness of .080 inches. The sample piston that I got has a chamfer on it so the "flat part" of the piston would be totally below the deck. I don't think that there would be any issues with the top ring or the ring land. Surprisingly, this isn't all that much cheaper than option 1 as the head gaskets are $110 each. People seem to be very uncomfortable with negative deck heights though.
3) Several of the pistons that I've looked at have pretty large top ring lands. I could get a set of these and machine off the top 27 thou. This is the least expensine option but makes me the most nervous. I'd also have to machine the intake.
Although I don't intend to race or autocross this motor, the truth is that I'm pretty hard on them. Although I'm getting very good at swapping motors, I'd like this one to last a little longer than the 200 miles or so that i got from the last one. I never really figurged out what went wrong so I'm trying to be a little more careful this time around.
I plan on using the crank (3.75 stroke and already magnifluxed) and rods from the last build. I did replace the one that was slightly bent :bounce:
I also plan on using the iron head (72 cc chamber and 200 cc runner) and am looking for a static CR around 9.75:1. I'll likely switch from the solid, roller lifter set up that I used to a hydraulic roller, but that discusion is for another day.
I was able to pick up a nice Motown block that needed boring. Unfortunately, it came with installed o-rings that had to be decked off because the placement didn't allow for an overbore. The net result is that I now have a deck height that is 27 thousanths below 9.8 inches. I picked up a cheap piston from Summit and verified the deck is even accross all eight cylinders.
I think that I have three realistic options for the pistons:
1) Purchase a set of custom pistons with a lower compression height so that I have a zero deck. This is probably the most expensive but not by all that much. I'd also have to machine the intake, but it's only money :crap:
2) I found a set of Felpro head gaskets with a compressed thickness of .080 inches. The sample piston that I got has a chamfer on it so the "flat part" of the piston would be totally below the deck. I don't think that there would be any issues with the top ring or the ring land. Surprisingly, this isn't all that much cheaper than option 1 as the head gaskets are $110 each. People seem to be very uncomfortable with negative deck heights though.
3) Several of the pistons that I've looked at have pretty large top ring lands. I could get a set of these and machine off the top 27 thou. This is the least expensine option but makes me the most nervous. I'd also have to machine the intake.
Although I don't intend to race or autocross this motor, the truth is that I'm pretty hard on them. Although I'm getting very good at swapping motors, I'd like this one to last a little longer than the 200 miles or so that i got from the last one. I never really figurged out what went wrong so I'm trying to be a little more careful this time around.
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