TWN or JENVEY injection ( Anybody have any experience with them?)

herman maire · 05-03-2006, 07:05 AM

Just wondering...I have a long block 95 993 motor and instead of just buying the stock intake is a single throttle body set up much better???

Jenvey cost $2500-3000
I still have not checked for the what the TWM set up cost.
Are there any others that are cheaper?

Are they worth it?? How reliable are they?

This would be for a street track/street car.

Also what can a 993 motor with hydrolic valves safely rev too.
Is it worth swaping in a 964 valve train if I plan to rev to 7200-7500 RPM.

Thanks for any info

911teo · 05-03-2006, 10:54 AM

Hi there

I went with the Jenvey throttle bodies. The TWM are similar in cost but from my research (no personal experience here) people tended to prefer the Jenveys.

The Individual Throttle Bodies set up will increase dramatically your throttle response. It will be like one of those old carb engine in perfect state of tune... It will be an incredibly fun engine...

But toghether with the throttle bodies you'll need a lot of other components (namely horns, linkages, fuel rails, air cleaners).

Realistically you need to budget $3,500-4000 for an ITB set up.

And it does not finish there as you can ditch your Motronic control unit because you'll need a complete new set up.

A new ECU and harness can cost anything from $2,500 to $8,000 depending on brand and options you decide to have.

Regarding the revving... The firs mod to Porsche (and any race engine builder) did to these engine was to go for solid lifters. Then I would address the valve themselves, the retainers (ti) and springs (ti).

After you address that the weak link would become the rods.

But my question to you is about the cams. If you want to have your engine spin to 7,500rpm you need to change the cams otherwise there is not much point.

I am in the process of having a high revving 993 engine built. We have done all of the above and with some DC62 cams will set the redline at about 7,500rpm.

Will the motor take 8,000rpm? yes... will it last long at 8,000? NOPE.