What approx output at the flywheel of

998 single 1 1/4
998 dual 1 1/4
998 single 1 1/2

standard everything else -

Thanks

Without having any numbers to contribute, assuming that a HS2 is able to supply all the air a 998 needs, you're not going to get a power increase with a single HS4, are you?

Twin HS2's should give a little more, but only by providing a more consistent mixture to each cylinder.

Assuming the 998 isn't restricted by the HS2 of course...

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Simon

The adventures of an owner builder in the Tallarook Ranges

Download and have a play with a program called win su.
Google it and you should find it. I think you can demo it for a week or something without buying the license. it will give you output figures for all types of different configurations of block, head, inlet manifold, carbi, exhaust, ignition etc... Also gives suggested needle configuration. I don't know how accurate it is but it is a bit of fun...

Google winsu download and you should find it.

doesn't do twins....

BIAM, I reckon the first set up would pull the skin off 1 bowl of custard, the second one, 2 bowls, and the third only 1 and a half

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did I tell you that I won a trophy?

HS4 and manifold on a stock 998 is worth a couple of HP over a single HS2.
That's why ALL the automatics (even 850 in UK) got an HS4 before the others.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.