Macca

Hi,

I have a 1994 993 C2 ROW spec with Steves chip. powerflow and RSR mufflers. I have discussed other mods with my Porsche mechanic and he has mentioned enlarged throttle bodies and possible hp gains.

Does anyone here know what is involved and who could supply enlarged throttle bodies? This is a pretty standard modification on many older performance NA engines so I was wondering if anyone has tried it. I am wondering if it is expensive, if there are gains and if the MAS or ECU would need changing.

Appreciate your help in advance.

Oh - and I might try cat bypass pipes but no one seems to be overly impressed with these on the board....

Cheers

Macca the Kiwi

CalvinC4S

Hello Macca,
I know that FVD has the T-body you mention.
In the US Automotion is the FVD hook-up. Hope that helps- Bill

P.s. I would think to get the most out of it, you would need to cut bigger valves into the heads?

Hank Cohn

Macca:

I sent you a reply privately with one vendor that I know carries the part you seek. It sounds like you have done some nice mods to your car to add some extra performance. I don’t know what the tradeoffs are with a larger bore TB, but I am sure that the gains are relatively small. What I do know is that an engine’s power really comes from the heads and the cams. While you can incrementally increase horsepower and possibly torque with some simple bolt-on mods, real power can only be realized by enlarging the intake ports, the exhaust ports to some degree, although that is difficult given the ceramic inset molded into it, smoothing the airflow through the heads and changing the cam profiles to better fill and scavenge the cylinders.

If you intend to drive your car on the street and continue to enjoy doing so, choose your next engine mods carefully or you will end up with an engine that is very peaky with a fairly narrow power band. In order to maximize those mods, you will need to change the gearing to keep the engine in the power band. Without building a race engine, it will be difficult to get much more than 280-295 HP out of your motor and still allow it to pass emissions. I am sure you can get pretty big HP numbers out of a 3.6 if you were trying to build a race only motor. You should be able to approach 360+ HP, but you will have a motor that will need rebuilding fairly often and one that is not suited for street driving at all.

Hank

Macca

Hank/Bill,

Thanks for your responses.

Yes this is a street car and I want it drivable at the very least! Your wisdom Hank is appreciated. I think you have summed it up pretty well - although luckily emmissions are not an issue here in NZ (would you believe!).

Cams and manifolds are something I do not want to touch (too expensive and for the track). I was working on the basic philosophy of air in and out. I suspect the throttle body would give better response above all but perhaps on a few hp advantage.


Appreciate your feedback guys.

Cheers

Macca the Kiwi

Caveman

Hi Macca,

I'd heard about this and asked my garage who I trust and they didn't think it added a lot. They reflected a lot of what the other replies said.

Cheers,

David
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