The 9 to 1 is a little iffy with out big boost and staying out of detonation I would say yes. With your set up you are not going to see high rpm. That is the piston killer. I will get flack for that last statement.https://www.jegs.com/tech-articles/superchargers.html
9:00 to 1 compression ratio if I'm reading that right - that's on the edge. Is this a street driver only of strip ? Street - for a while as long as you are not really hammering/ revving it all the time.... Strip - probably not for long..... Those blowers make a lot of power and can really blow stuff up - especially cast anything. Forged Pistons would be a lot better. My opinion
This must be an afterthought? If you keep the max boost low is should be ok. But by doing that you’ll be making blower noises and dragging the parasitic loss just from driving the blower. Get forged pistons
I suppose why he asked the question. Ive got a hair up my ass to put a 671 on a bone stock SBC 307 with stock flat top pistons and the shitty stock heads. Those 307 boat anchors are almost free and not 10gs though. Sounds sweet don’t it?
Would not care about to much about the pistons as much as the boost, general rule is that you should o-ring the cyl's with anything over 9# of boost. and in reality using a non stripped blower (and a little loose for street) @ 3# will set you way back in the seat.
I don't put cast pistons in anything I want to last very long anymore... Forged are always worth the money, in my opinion; especially if there's a power-adder or high compression involved.
I was going to buy the engine .. it it was a good price we worked out a deal I did some research and wanted to reach out for some other opinions Sent from my iPhone using The H.A.M.B. mobile app
I wouldn't put cast pistons in anything anymore especially in blown applications. I had an experience with the engine in my convertible that makes me a believer in forged pistons. When I built the engine the only kit could buy had forged pistons, the engine always detonated and got worse the longer the engine was ran. Short story I had an engine knock when I got home from the lead sleds in Salina 3 years ago. Engine siezed a piston on the wrist pin. A cast piston would have been destroyed. A new piston , and rings ran a hone in the cylinder, engine is good as new. I did get the cause of the detonation fixed as well
In addition to the high 9:1 on a cast piston you also need to be cautious about the skinny connecting rods, and head gaskets. Lots-o-places for things to go wrong. .
No you won't. As long as the boost is not silly high (I have an opinion on low boost but I'll keep it to my self) and you don't rev it 'til it comes a apart you should be fine. @sunbeam back in the '90s I had a friend at MOPAR Performance that said stuff that you could take to the bank and nearly everyone on this board would scoff at. I put some of the things he said to the test. He's retired now he was a grey beard back then and he knew his chit.
I'm a bit late to the question at hand.... heres some truths in my opinion and from my experience with hemis and superchargers. can you bolt up a supercharger to a stockish 331 engine with cast pistons and run it? Yes you can, you easily can have a street engine that will live but there are many limitations. you need to keep in mind a few things, piston speed, cylinder temperature, timing, and flame travel. One you absolutely need to kept the boost fairly low, I wouldn't exceed 3 to 4psi at 5500 rpm and I wouldn't take it there very often. stock rod bolts are one of the weak points as with the rods, pistons & rings, and exhaust valves. two, you need to keep the tune dam near perfect to avoid detonation because cast pistons will melt and/or crack and you run the risk of breaking the cast iron top ring or over heating it and the ends touch and it seizes in the cylinder or breaks a ring land. ALWAYS start rich and work back from there, carbon fouling is better than a lean condition. Period. MAKE SURE your carb tune never leans out or you'll detonate! three, keep your timing mild. lock out the mechanical advance and start with 29 total and work towards 30 to 31 total and leave it at that. last thought but look for a good hot spark, I prefer a magneto but any good ignition will do and run 0.030 gap. I run two heat ranges cooler on your plugs, I run a champion no 300 (N9YC). Stock for hemis was no 38s. ultimately detonation, higher boost your rotating assy can handle and rpm will kill a stock hemi on boost. Now, all of this said it's still no guarantee that it will live. if your building a hemi do yourself a favor and invest in the bottom end. Go forged pistons, good stainless top ring, aftermarket rods (I run BBC 7" h-beams) and stud the bottom end, and don't forget to run quality exhaust valves!...... then run 9psi or higher (highly recommend o-ring but ypu can also run SCE ICS Titans and not machine in grooves). There's a lot going on in a supercharged engine but there fun. Pics posted of my destroked & supercharged hemi that I built and tuned. I run about 9ish psi due to belts slippage and turn 6800rpm. Sent from my SM-G900V using The H.A.M.B. mobile app
Just make sure that the top pulley is bigger than the bottom pulley with a loose blower and you'll probably be OK.
That ring set number looks like a PAW special, NOT SpeedPro. https://docplayer.net/34293274-Performance-automotive-warehouse.html Older Speed Pro info would suggest .016 end as a minimum for the top ring in a ~4" bore for performance street use. The second ring would be .020" minimum. The generic Supercharged category would START at .024" First and Second. https://www.aa1car.com/library/ring_info_speedpro.pdf
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