3.2 Intake on a 3.0

[redstormcoach]

I read somewhere that 3.0 911sc owners upgrade to a 3.2 intake for more HP. Is that true?

How to do it and what's needed for a '79 3.0 non-turbo?

[AFM744]

The 3.2 intake is typically installed on the 930 as part of an electronic fuel injection conversion (please see my h-link in my sig). The stock CIS injectors will not fit the 3.2 manifold, nor will the intercooler. The stud format is the same, but the 3.2 manifold is 40.5mm ID vs the stock Turbo's intake ports at 32mm.
You say your car is a '79 and a 3.0, but in '78 they went to the intercooled 3.3 motor IIRC. Let us know if/what other mods you already have.

[redstormcoach]

This is not a turbo. Its a 1979 911SC 3.0 litre.

[mb911]

only if useing an aftermarket efi like bitzracing.com or the likes. thats where I started.

[911nut]

Red,
As stated by Ben, you would have to go to EFI to make this mod. With the large port heads that you have on your '79 SC you will get a bump in low end torque from the Carrera manifold. Additionally the removal of the air sensing plate that is part of CIS will yield better throttle response and an additional torque bump.
Long intake runners increase low end torque due to the volume of air sitting in the runners. Air has mass and the momentum generated by the column of air in a long intake runner improves cylinder filling at low engine speeds.

[AFM744]

Originally Posted by redstormcoach

This is not a turbo. Its a 1979 911SC 3.0 litre.

Pardon my assumption.

[flat6pilot]

I have an 80 euro spec (large diameter intakes) motor in my SC running Bitz EFI. Are there any mods that need to be done to the Carrera runners themselves or my intake ports? I.E. port matching..??

thanks
kyle

-I just realized this thread is in the Turbo section.. ???

[JohnJL]

Hi Kyle, saw your PM. I'll answer here for other's benefit too...

On both the 80 and 83 heads that I've used with the 3.2 aluminum intake I needed to do some modifications for fit and some for performance/flow.

In both cases it was necessary to use phenolic spacers which the SCs didnt use. The spacers were necessary to allow for porting to the heads for the injectors to point into the intakes properly. If you just plop a 3.2 intake onto SC heads your injectors will be partially obstructed by the intake surface. If you use a spacer you can then dremel/machine the intake manifold/spacer/heads into a smooth contour into which the injectors aim cleanly.

As a result of using the spacer, I also needed to install longer studs. The pattern and spacing is the same but the studs are not long enough to fit the intake, washers, gaskets and nuts.

In both cases I did some minor grinding to the heads to smooth the "step" between the intake and the heads. Its not hard (use a 3.2 manifold gasket as a pattern) but you need to be careful to make each head exactly the same and you need to be careful to leave enough meat on the injector side for the gasket to make a good solid seal.

Its a "heads-off" job in my opinion.

Hope that helps.

Oh, and if anyone is going to do this I have a spare set of 12 gaskets and 6 spacers. And 26lb injectors, which are what you need for up to 290 hp.