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Help needed to new 12A NA project

Old 03-27-13, 05:14 AM
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Help needed to new 12A NA project

Hi

I need some advise for my new rebuild.

The rx7 1982 is a street car (not a daily driver) that do some times trackdays and gymkhana. I want port the 12a engine, and want the best power i can get from it, i would like 150/160rwhp, but my redline is 8500rpm and i ideally want top power at 8000rpm.

I have a weber 48 ida, RB RB road race header, RB power pulse main muffler, and a custom mid dual pipe.

What the size port combination that you recommend me? race streetport intake and race exhaust port? Race streetport intake with a smaller exhaust port? Another options are well received.

Regards
Old 03-27-13, 01:41 PM
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well depending on the health of the engine and the tuning, you actually should be in the 140-150 rwhp range already.

so if you still want to port, i'd do a street port. that should have you in the 160-170whp range

give or take of course depending on the dyno you're using
Old 03-28-13, 01:03 AM
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If you want a fast motor bridge it ,you have the right carb and header for it . and I think the last posters rwhp numbers were a little to generous . my old street port 13b fully tuned with the proper exhaust and carb produced 166 rwhp at 7800 rpm so logically the 12a with a street port would be a bit lower .
Old 03-28-13, 10:01 AM
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Originally Posted by mattallac
and I think the last posters rwhp numbers were a little to generous
yeah could be, not a lot of data points, actually.

a stock 12A with the pro7 setup, stock carb, stock exhaust, will do 110-112rwhp. add an RB header and you're in the 120-125rwhp ballpark, but after that its a bit hazy.

a bridge should be around 180-210, bridges vary in size! and the P port should be like 225rwhp
Old 04-02-13, 01:36 PM
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I will do a large streetport and machting exhaust port from Pineapple Racing. Hope achieve 160rwhp!

Regards
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