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Machine small intakes or get 3.2 heads?
So I started this thread over in the tech forum and didn't get a whole lot of replies so I'll ask over here. For a street car with some autoX work, am I better having my small intake SC heads ported to increase HP and rev range, or should I get a set of 3.2 heads and have them totally rebuilt. The known factor is that the 3.0 heads were redone 10k ago so guides, valves, seats should all still be goood. I am upgrading the engine w/ an S mod cam and new pistons.
This is what I learned from one other pelican...... Originally Posted by EarlySport A long time ago I recall reading an article in European Car magazine that used a lot of flow bench data that comprehensively showed that ported SMALL port heads were the best flowing. I think this maybe because the small port heads can be opened up to a larger size and the port can be raised while doing so, providing a more direct path. Of course the manifold would have to be ported as well to match. I am soon to rebuild a 3.0 and I have small port heads standard, but I've bought a set of 3.2 heads as well. Not sure yet which way to go, so I'm interested to see what other feedback is posted. Done on 912 engines a lot, You can angle cut the head intake flange 7 degrees and cut the port to match which will help straighten out the flow, carbs are tipped out a bit.. __________________
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joe ------------------ '69 911 E Targa - aka "RoxiE" |
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good question. I've always heard the 3.2 heads flow REALLY well.
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-Jay '74 Mexico Blue 911 3.0 EFI (Fast and Loud) '70 914/6 Race Car (Faster and Louder) '71 73RSR tribute vintage race car 3.0 '68 SWB 911T "RENNRAT" 2.8 twin plug/915 gearbox '81 Magenta IROC clone in progress 3.6 varioram/G50 |
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For all out race high RPM use, that's what I've heard. I'm curious if there are any folks who have tried raising the port when opening the small intake.
Again, I'm not building a race motor so if there are any special techniques to opening my small intakes while preserving power in the 3-4k range, I'm all ears.
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joe ------------------ '69 911 E Targa - aka "RoxiE" |
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No Clue
Interested in feedback on this same topic as well...
Gordo
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Don "Gordo" Gordon '83 911SC Targa |
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