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I'm building a warmed-up 2.8. "Why a 2.8?" has been asked in this forum. It's for a light dune buggy (mid-engine) and should have plenty of power-to-weight for this old man. Why warm it over? I'm lifelong into modified engines and think any engine should an exhaust note that's at least crisp (especially any full-dual six!), a slightly ragged idle, and a rate of acceleration that rises with the rpm.
After two full days on the pushrod performance forum, I've found invaluable resources for cams, intakes, and more, thank you all. However my luck has run out. Questions (you knew that was coming, right?):
First, the important one: You know performance bits have to work together. I'm good except for higher-compression pistons. I did find the long discussion on shaving and dishing various factory pistons. What about using the factory 12.5:1 domed piston, cut down? The GM performance books say it might have to be milled for valve clearnce with a long-duration cam, suggesting that the dome would stand a good bit of milling. Is anyone here up on this or does anyone have access to such a piston to caliper it out? (No need to saw it up, just see if the dome is thick all over.) Otherwise, does anyone recommend an aftermarket piston maker for this job?
Now two just for curiosity's sake:
1) The seller said this engine was from a '91 Firebird, which I think only had the 3.1, but it is clearly a 2.8. The serial number starts out "AO91" and ends "AAH" and there's a big "L" cast into the right side of the block. It has the taller pistons, thinner head gaskets, and multi-port injection, so I'm guessing '87 Camaro. What do you think?
2) This is weird: The pistons and combustion chambers are full of thick black "stuff" that looks and smells more like burned oil than too-rich soot. No, the honing marks are still on the cylinder walls!! A semi-expert neighbor thinks it overheated, ruining the rings, but after (mumbly-mumbly) years, that's a new one on me.
Now for my contribution: I saw the Bow Tie aluminum block mentioned and have some further details on it: The stroke is limited to 3.2", meaning a stock 2.8 or else custom crank. The bore is limited to 3.582", again meaning 2.8 or custom pistons. It's still tempting, as it weighs 47 pounds less than the iron block, fits FWD and RWD (starter either side), has splayed four-bolt mains and the bigger late mains, and accepts aluminum heads, which again weigh less that the iron ones. C'mon lottery!
After two full days on the pushrod performance forum, I've found invaluable resources for cams, intakes, and more, thank you all. However my luck has run out. Questions (you knew that was coming, right?):
First, the important one: You know performance bits have to work together. I'm good except for higher-compression pistons. I did find the long discussion on shaving and dishing various factory pistons. What about using the factory 12.5:1 domed piston, cut down? The GM performance books say it might have to be milled for valve clearnce with a long-duration cam, suggesting that the dome would stand a good bit of milling. Is anyone here up on this or does anyone have access to such a piston to caliper it out? (No need to saw it up, just see if the dome is thick all over.) Otherwise, does anyone recommend an aftermarket piston maker for this job?
Now two just for curiosity's sake:
1) The seller said this engine was from a '91 Firebird, which I think only had the 3.1, but it is clearly a 2.8. The serial number starts out "AO91" and ends "AAH" and there's a big "L" cast into the right side of the block. It has the taller pistons, thinner head gaskets, and multi-port injection, so I'm guessing '87 Camaro. What do you think?
2) This is weird: The pistons and combustion chambers are full of thick black "stuff" that looks and smells more like burned oil than too-rich soot. No, the honing marks are still on the cylinder walls!! A semi-expert neighbor thinks it overheated, ruining the rings, but after (mumbly-mumbly) years, that's a new one on me.
Now for my contribution: I saw the Bow Tie aluminum block mentioned and have some further details on it: The stroke is limited to 3.2", meaning a stock 2.8 or else custom crank. The bore is limited to 3.582", again meaning 2.8 or custom pistons. It's still tempting, as it weighs 47 pounds less than the iron block, fits FWD and RWD (starter either side), has splayed four-bolt mains and the bigger late mains, and accepts aluminum heads, which again weigh less that the iron ones. C'mon lottery!
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