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Discussion Starter #1 (Edited)
So I'm getting sick of adding a quart of oil to my engine every day or every other day and I decided it's time to do something about it. I was planning on stroking the 350 to an n/a 383 a while ago, but not too long ago I decided I was going to supercharge it. Basically, the heads on this engine are garbage and they're leaking oil and I figured I'd fix that and maybe get some more power by getting some new aluminum heads. A friend from another forum gave me his combo for his 383 and these are the heads he used:

http://store.summitracing.com/partdetail.asp?autofilter=1&part=DRT-11521122&N=0&autoview=sku

My question is, would those heads be good for a supercharged motor? I'm planning on getting a 6-71. I'm thinking the combustion chambers might be too small, but I'm hoping 215cc's will be fine? I'm trying to go for as low of a compression as I can (hopefully 8:1), so I'm pretty sure I'd need bigger chambers. This is going to be a street/strip car and I'm looking for hopefully 600 hp/600 ft lbs. I also don't mind if it drops the power of the engine right now because it's going to be getting a rebuild soon (hopefully) and at least if the compression went down I wouldn't have to use 91 octane. :p

Thanks,
Matt
 

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You need to know what pistons you currently have in the motor (since I think all you are planning on doing is changing heads and installing the blower) If your pistons are flat top with the 4 eyebrows then I suspect with the 64cc chambers you will be above the 8:1 you are looking for.....how much above I couldnt say without actually measuring (CCing) your parts and figuring out your REAL compression ratio.

With the 64cc chamber I "think" you need to have dished pistons to get down to 8:1CR.....So you might have to buy pistons too so you can get the CR down to a safe level for supercharging....just my 2 cents on this....

Good luck:)
 

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SuperNova69 said:
I'm thinking the combustion chambers might be too small, but I'm hoping 215cc's will be fine?
This sentence makes me wonder if you know the difference between Intake volume and combustion chamber volume.

These heads have an advertised 64cc combution chamber volume. What volume does you current heads have?
Stroking an engine will increase your compression ratio because the swept volume is higher.
I think you need to carefully figure out all the parts you'll need and learn to measure volumes with a burrette and calculate compression ratios. Supercharging an engine is a fairly advanced project. You don't want to mismatch components.
 

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Discussion Starter #4
Paul Wright said:
This sentence makes me wonder if you know the difference between Intake volume and combustion chamber volume.
No disrespect, but how did that sentence lead you to believe that?

Also, 69NovaSS, what I meant was, I'm looking to replace the heads that are on the engine right now with the heads that I plan to use on the 383 later. I am NOT planning on just throwing heads and a blower on and calling it a day. What I'm basically wondering is, what is the recommended size combustion chamber and intake runners for a supercharged motor? Sort of a "universal rule," you know?

And Paul, my heads are 041 castings. Mortec says:

3947041....69-70...302/350......"Right angle" casting identifier, 64cc chamber, accessory holes, good HP head

I'm just trying to find a good head that will flow well enough to support a supercharger and get around an 8:1 compression ratio with the right rotating assembly. Guess it was more complicated of a question than I thought, but I did ask it when I was tired last night. :eek:

Thanks,
Matt
 

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Well, it sounded like because you asked if 215 cc's would be ok that you thought 215cc's was the combustion chamber volume.
 

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Discussion Starter #6
Heh, well I apologize. I meant 64cc sounded pretty small for a good supercharged engine to build a lot of boost. I was hoping 215cc would be decent for the intake runners, though. :)

Matt
 
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