jhy

I am building up a 3.3 engine and need some recomendations/opinions on which cam I should use.

The engine will basically be a conservitive efi build for the street
I am not looking for big horspower....just maybe 450-500 hp...
I am keeping stock pistons
using the 3.2 manifold for the efi
using k27-7200 turbo
will run no more than 1bar of boost.

the options of cams I have are the following
964 cams
993 supersport cams
gt2 evo cams

many people advise me to go with the evo cams, but am just afraid that it may be to radical for me.....meaning, that I want the car to be a good street car....not something where I have hard cranking....poor idle..low bottom end...etc...

Any advice on which cam I should get???...I am thinking of just getting the 993 ss cams...since that is in between the 964 and the evo.

thanks in advance.

DonE

The cam is the heart of the motor, so be very careful in matching the cam with the engine.

First, you need to reconsider the turbo as it will limit everything else you have and your EFI rebuild will be a waste of money.

Once you decide on the turbo, EFI system, injectors, headers, headwork (if any) and IC, then decide on the cams based on what you will do with the car (track or street). For me, the 964 are perfect for the street and any DE's I will do, and my motor produces 530hp and 470 ftlbs. EVO's sacrifice low end. If you will be on the street, 330 SC cams are great too. Depending on your budget, the correct way to finish your build is to call Webb, Elgin, or Dougherty for a custom grind specific to your motor and expectations.

IMO, 450 - 500hp is big HP for any build, and might be a bit more than what you will be able to get with your build sheet above.

Good luck

Geoffrey

Custom ground camshafts will give you the best results. GT2 Evo cams are not all that radical and I think they are the best off the shelf camshaft available from Porsche. I don't feel they sacrifice any real bottom end, however, running with the factory stock 7:1 pistons (more like 6.5-6.8:1) and longer duration, your dynamic compression ratio may not be all that high. I've always run the GT2 Evos with 3.4l higher compression.

DonE

Geoffrey - what numbers are you using for timing the EVO's?

m42racer

In my opinion, call Stephen @Imagine and ask him about the Cams he used in an engine he dyno'ed. Nothing like having dyno numbers. If I recall, he made over 420Hp on an engine with no other internal mods. from your concerns, he should be able to give you a dyno print out showing the engines Torque curve.