|
|
|
|
| Author |
|
|
Stranger on the Internet
Join Date: Apr 2004
Location: Bradenton, FL
Posts: 3,244
|
Wastegate Discharge
My wastegate dumps out a short pipe under the engine. I would like to pipe it to the inlet or outlet side of the muffler, just to tidy it up a bit. Would that be unusual? I don't know where 930's dump to. The wastegate is a little Tial, 38MM, and the pipe is maybe 1-1/4 or so.
It can be seen on the left. The Flowmaster is back off, and the M&K is going back on, as soon as I fab up a new pipe from the turbo. I was thinking maybe a "Y" fitting? TIA Pat 
__________________
Patrick E. Keefe 78 SC Last edited by patkeefe; 03-23-2013 at 05:42 PM.. Reason: Flowmaster |
||
03-23-2013, 05:32 PM
|
|
|
Registered
Join Date: Jul 2008
Location: Central Washington State
Posts: 4,403
|
Didn't some of the earlier mufflers have provisions where the waste exhaust was routed to the front of the muffler via some sort of plumbing?
Years ago I took off my WG shorty-muffler in favor of an extension and matching tail pipe. My single-out Fabspeed muffler exits on the right side and the WG on the left. From the rear, looks like a dual out muffler setup. I don't hardly notice the WG when it opens, since it's blowing straight back behind the car now vs down beneath the engine as yours is pointed.
__________________
Mark H. 1987 930, GP White, Wevo shifter, Borla exhaust, B&B intercooler, stock 3LDZ. |
||
|
03-23-2013, 05:39 PM
|
|
|
Stranger on the Internet
Join Date: Apr 2004
Location: Bradenton, FL
Posts: 3,244
|
I don't know. I'm sure I've seen a picture of that arrangement, but I can't find one now. I would think a "Y" at the inlet to the muffler would be a decent flow point. On my car, it's a PITA to increase that to a 3" and make it look like a dual out. I have way too much oil plumbing in the way.
__________________
Patrick E. Keefe 78 SC |
||
|
03-23-2013, 05:45 PM
|
|
|
Non User
|
__________________
Infraredcalvin - AKA Pat '76 Turbo Carrera #311 - Factory LSD, Sport Seats ‘71 914-6 GT 3.4L twin plug track car '75 914 GT clone project '71 914 track car, fresh 2165 FAT motor (for sale soon) |
||
|
03-23-2013, 08:08 PM
|
|
|
Preferred pronoun:Maestro
Join Date: Sep 2012
Location: Group W Bench
Posts: 11,351
|
On the factory exhaust of my `80 the wastegate was piped into the muffler. Of course, the `80 is a Euro model - not certain if they did this on the US models.
__________________
When in doubt, use overwhelming force. |
||
|
03-23-2013, 08:14 PM
|
|
|
beancounter
Join Date: Jan 2008
Location: Weehawken, NJ
Posts: 3,593
|
Factory exhaust on a '79 USA model 930. Just like the workshop manual illustration posted by mr. InfraredC above.
 
__________________
Jacob Current: 1983 911 GT4 Race Car / 1999 Spec Miata / 2000 MB SL500 / 1998 MB E300TD / 1998 BMW R1100RT / 2016 KTM Duke 690 Past: 2009 997 Turbo Cab / 1979 930 |
||
|
03-24-2013, 04:06 AM
|
|
|
|
Registered
|
I don't know if this is relevant but some books show an increase in torque around 1983/84 from 303 lbs/ft to 314 lbs/ft on the Euro Turbo. The only major engine modification I can track down from that time is the venting of the wastegate being changed from into the rear box to it's own small silencer.
|
||
|
03-24-2013, 05:19 AM
|
|
|
Registered
Join Date: Jul 2003
Location: Back in B'ham, AL
Posts: 3,459
|
Quote:
|
||
|
03-24-2013, 05:36 AM
|
|
|
I've gone native
Join Date: Sep 2011
Location: Long Island, NY
Posts: 1,695
|
BB makes a muffler pass side out w a drivers side wg pipe as mark h describes.
|
||
|
03-24-2013, 07:42 AM
|
|
|
Registered
Join Date: Oct 2007
Location: Calgary
Posts: 364
|
How is that 38mm wastegate working for you?
I find I need to use a 46mm. Any boost creep with the 38mm?
__________________
1981 411 rwhp, Ruf intercooler, 964 cams, Turbo Kraft injector blocks, Extrude honed intake, 7006 Turbo, Tial wastegate, RarlyL8 exhaust, MSD6al |
||
|
03-24-2013, 11:46 AM
|
|
|
Registered
Join Date: Jul 2003
Location: Glorious Pac NW
Posts: 4,184
|
Quote:
So you can potter about quite inconspicuously (other than the increased growl through the GHL's over 3000 as compared to factory H/E's) - but should the wastegate open, it's quite obvious..
__________________
'77 S with '78 930 power and a few other things. |
||
|
03-24-2013, 12:13 PM
|
|
|
Stranger on the Internet
Join Date: Apr 2004
Location: Bradenton, FL
Posts: 3,244
|
Maybe a little boost creep, but I can't say I notice it. I only run 5.8 psi boost. Quite frankly, I had the new 38, and was too cheap to go with the bigger wastegate. The Tial is much more precise than my old wastegate was.
__________________
Patrick E. Keefe 78 SC |
||
|
03-24-2013, 12:16 PM
|
|
|
|
Stranger on the Internet
Join Date: Apr 2004
Location: Bradenton, FL
Posts: 3,244
|
Spuggy, after seeing the pictures of the factory wastegate outlet, I notice that the muffler configuration is in and out, same side, which may not be optimal. But, I don't know how the factory constructed the mufflers, so maybe it's not so bad. If I go in on the inlet side of my M&K muffler in a "Y" fitting, I don't think it will limit the wastegate flow, as the WG discharge pressure will certainly be higher than the turbo outlet, and may entrain some flow from the turbo. I willl certainly test it next time it goes to the dyno
__________________
Patrick E. Keefe 78 SC |
||
|
03-24-2013, 12:28 PM
|
|
|
Registered
Join Date: Jul 2003
Location: Glorious Pac NW
Posts: 4,184
|
Quote:
 From pictures someone posted 6-7 years ago, I think that location just bypasses a foot or 3 of pipe-with-big-holes-in-it. Quote:
It may cost a few ponies. Probably no big deal, so long as you can control boost. Is it track noise restrictions you're concerned about? Only downside of the dump pipe I've ever seen was the 9" blue flame burning the epoxy floor coating at the dyno... By the time it opens, I find the motor is making so much noise anyway that I don't really notice any more...
__________________
'77 S with '78 930 power and a few other things. |
||
|
03-24-2013, 01:09 PM
|
|
1976 Porsche 930 3.0 turbo
The Beater
71EURO6
