Timspu

I have a standard 930 Turbo, is adding a free flowing muffler a beneficial mod?
I don't want to run into replacement headers. Was also thinking of a 1 bar boost spring.
Has anyone got any feedback on this?

Thanks
TIM

HkPlinker

I went with FabSpeed exhaust and a 1 bar spring. I also up-graded my inner cooler, which is highly recommended. My car now picks up boost at 3200 rpm. I love it.

964speed

free flowing muffler and 1 bar spring with make your car perform better...

it becomes a very slippery slop...

than you upgrade the turbo and intercooler ...

Than you'll change the headers...

than you'll think about a race gear box...

OR EFI...

This Porsche thing is a needle in the vein!

Mark Houghton

A free-flowing muffler is the first and probably most economical modification that yields good results, especially if you were also saddled with a catalytic converter. The less exhaust back pressure, the better for turbo cars. Follow that with a larger intercooler to get a cooler charge temperature and you'll see HP gains there as well. Both are easy bolt-on mods, the IC being most important if you plan on running much past the stock boost of .8 bar.

Then, slap in a more efficient turbocharger. Follow those changes with a set of headers, play around with different cams, programable ignition and adjustable WUR...and you'll have a car that runs very strong.

Definitely a "needle in the vein". Porsche 930's are more addictive than heroin.

MUSSBERGER

And keep all the stock parts!

Timspu

Thanks for the additinal info. I am going to stick with just the muffler as i don't want to spend thousands on performance parts which i know can easily be done as the wish for more power.

Thanks
TIM
Newby 930 owner

John@Fabspeed

Hey Timspu, the mufflers will really really wake up the car in sound and power, and just make the 930 come alive and more fun to drive. Let me know if you decide to do a muffler or Headers upgrade and I will take care of you of the price as a member discount. Let me know if you have any questions.
thanks,

Timspu

Hi Alex,
Thanks for the offer, i would like a muffler that is not too noisy especially at constant throttle while cruising, my car is a UK spec car so no Cat converter fitted. What would you recommend?

Thanks
TIM
1988 Targa Turbo

WPOZZZ

I would suggest a single out muffler as a dual out will drive you bat sh*t crazy with the cabin resonance. I had a B&B dual out and replaced it with a Fabspeed single out and couldn't be happier. The butt dyno fells like I lost a little power, but I can drive the car now without losing my sanity.

Mark Houghton

I love my single out Fabspeed (exit right hand side). Made a substantial difference in performance, and the noise in the cabin went up just a touch from the stock muffler. Sounds great, especially for those behind you.

WPOZZZ

That's the one I have and I love it!

Timspu

Is there any comparison between Fabspeed and Rarly8 Muffler? What would be recommended, value for money?

Out of interest with WOT my turbo starts boosting around 3200 Rpm and full boost after 4k, power drops off around 6k. With the muffler change when will full boost be noticed?

I am also looking at installing a manual boost control to have around 0.9 to 1.0 barand ensure waste gate remains closed until required to open. Coming from a 993 C2 the Turbo engine looks pretty complicated with lots of pipe work and valves, can some one confirm that the MBC connects in the flexible pipe from the intercooler to the lower side of the Waste Gate.

Also i have a boost gauge which does not always stay at Zero when off boost, normaly sits on around 0.2 bar, Is the transducer for the gauge the large Orange VDO unit under the intercooler? Hoping its a sendor issue and not a bad gauge as i did have an alternator failure which caused an over voltage sending the tacho to 7 k rpm and fluctuating boost gauge.

Sorry for the amount of questions but this forum is the best source of reliable info out there.

Cheers
TIM
1988 Targa Turbo

WPOZZZ

I wish I could chime in on your question, but my car is modded. It pulls hard from 3k to 7k+. I think you are running out of power at 6k as it may be the threshold for the stock 3ldz turbo.

Here's a Fabspeed exhaust clip.

Mark Houghton

Out of interest with WOT my turbo starts boosting around 3200 Rpm and full boost after 4k, power drops off around 6k. With the muffler change when will full boost be noticed? There really isn't any "rule of thumb", depending so much on level of tune and stock vs. modified. You might see boost onset a couple hundred rpm's sooner.

I am also looking at installing a manual boost control to have around 0.9 to 1.0 barand ensure waste gate remains closed until required to open. Coming from a 993 C2 the Turbo engine looks pretty complicated with lots of pipe work and valves, can some one confirm that the MBC connects in the flexible pipe from the intercooler to the lower side of the Waste Gate. That would be the hose that sends the boost signal to the WG. Simple boost controllers are installed in-line there, to interrupt the signal until whatever set point is reached.

Also i have a boost gauge which does not always stay at Zero when off boost, normaly sits on around 0.2 bar, Is the transducer for the gauge the large Orange VDO unit under the intercooler? Yep, that's the sender. Somewhere I have the resistance specs at various pressures, so you can bench-test with an ohm meter. Most likely the gauge, though.

Mark Houghton

Tim, go here for specs on the boost sending unit.
http://forums.pelicanparts.com/911-9...ance-data.html