Exhaust options for twin turbo 993

[moparrob]

I recently picked up a 1975 wide body that is running a 1996 993 twin turbo 3.8 engine, and the exhaust comes straight out of the turbos into two short pipes. Needless to say, it is LOUD and tough on the neighbors when I fire it up.

I want to add a muffler system in place of the straight pipes and was wondering what good options currently exist. Is this something that likely needs to be custom fabricated as this is not a stock turbo configuration?

This is the car:





and this is the exhaust setup:





You can see how it mounts directly to the turbos:









My rear valance already has openings for dual side exhausts in addition to the center exhaust outlet.

Any suggestions would be greatly appreciated. Thanks.

[turbo ride]

Wow I bet that things is just a beast! :-) Cool.
Me thinks you'll need to go full custom. The 993 butt is much wider and I think the mufflers are housed off to the sides. So I don't think OE 993TT exhaust will fit in the early body work.
So custom. Either local (I'm sure you have plenty of options in LA - just gotta figure out who) or ship (better yet DRIVE) the car to a known expert (Brian at RarlyL8) for fab work.

[Porsche 935]

You could add some supertrapp mufflers to the ends of those pipes.

[TurboKraft]

You're looking at a full custom setup, nothing off-the-shelf.
'Trapps in place of those tips will do very little.
Do you want to maintain the dual center outlets?

[moparrob]

Thanks for the info Chris, I sort of figured that would be the case. I wish your shop was closer.

I am really indifferent as to whether the exhaust exits from the center or from the two sides. I just want the sound be something more manageable. It seems like you could route the exhaust and squeeze in a glass pack or something between the turbo and the exiting tip. I'm not too concerned about power loss because this thing is an absolute monster.

Are there any vendors who sell the exhaust flange that mounts to the turbo output which could be welded to, so I could have a local shop configure the exhaust?

[TurboKraft]

355mi from Los Angeles, we get cars from there all the time.

Those look like plain Ford 5-bolt turbine exit flanges, nothing special. You can get those flanges all over the place. Probably 2.5" exit hole. You can exit off the turbo, make a 180deg (2.5" OD tubing on 2.5"CLR) and run to a pair of compact mufflers of your choice: Magnaflow, Burns. whatever.

Easiest to then exit the stock left/right outlet locations; more difficult to 180 back around and exit out the center again.

[moparrob]

Thanks again for the education. I will check around locally and see if I get a degree of comfort with the local vendors.

I did some checking online and most of the 180° 2.5 inch OD tubing I have seen has a much higher centerline radius, closer to 3.75 inches or 4.0 inches. Do you buy those pre-bent or do you bend those yourself?

[TurboKraft]

PM sent

[onboost]

Originally Posted by TurboKraft

355mi from Los Angeles, we get cars from there all the time.

Sounds like a nice road-trip to get acquainted with the beast to me!

[Rufian]

With those center outlets you can squeze some short Burn Stainless cans,,cheers.

[moparrob]

Thanks for the tip. They are an hour from my house so I can actually drive the beast there. I will call them this week.

[lee88]

Agree the OE 993TT exhaust system prob won't work here. It has two sets of mufflers actually in addition to the cats, and the system is kinda serpentine and all coiled in the rear fenders and number area. Custom setup prob is your only route, good luck getting it squared away.

[RarlyL8]

Can you take a picture from under the car so we can better see what(space) you have?

[moparrob]

Chris, I will not have a chance to get under the car until Friday. I will post some pictures after that. Thanks again for the help.

[TurboKraft]

Originally Posted by lee88

Agree the OE 993TT exhaust system prob won't work here.

Absolutely will not work in this application.
Look at the arc from the rear fenders to the bumper on a 993 vs. a 930 -- the 930 is concave, plus has an oil tank occupying the right rear.

[moparrob]

I finally had a chance to get under the car today and get some pics. It definitely looks a bit tight up there...












I have a few safety issues to address before I focus any further on the exhaust system, but I will definitely update the thread when I get it done. Thanks again.