| Slant Six Forum https://www.slantsix.org/forum/ |
|
| Turbo Exhaust Pipe Diameter https://www.slantsix.org/forum/viewtopic.php?f=30&t=59487 |
Page 1 of 1 |
| Author: | casedawg [ Mon Apr 18, 2016 3:40 pm ] |
| Post subject: | Turbo Exhaust Pipe Diameter |
What diameter of exhaust pipe should I be running from the turbo to the back of the car if my goal is 3-350HP with an HX35? Is 2.5" adequate or should I go to 3"? Thanks, Casey |
|
| Author: | Dart270 [ Mon Apr 18, 2016 3:47 pm ] |
| Post subject: | |
I would go 3". Had 2.5" on my car when it was in the 275-300 HP range and the step up to 3" made a significant difference. Lou |
|
| Author: | casedawg [ Mon Apr 18, 2016 5:02 pm ] |
| Post subject: | |
Lou, Did you make only the change to 3" and see the improvement? What improvement did it make? More power over all, down low, or up high? Thanks, Casey |
|
| Author: | Dart270 [ Tue Apr 19, 2016 8:30 am ] |
| Post subject: | |
Yes, only the change to 3". Boost came up quicker and more power overall. That's about as much detail as I remember. Boost rise was the most noticeable thing on the street and the 1/4 mile times were perhaps 0.2-3 sec faster. Most of that was not gained in the 60 ft. Lou |
|
| Author: | casedawg [ Tue Apr 19, 2016 2:33 pm ] |
| Post subject: | |
Good to know. I'll plan for 3" then. Any trouble areas fitting 3". |
|
| Author: | Dart270 [ Wed Apr 20, 2016 6:07 am ] |
| Post subject: | |
Watch up front past the tbar, going under the tbar/trans Xmember, then between gas tank lip and frame rail in back. Good to angle (big oval) muffler upward and I often aim rear of muffler toward the dr side of car. Use muffler with both ends (inlet+outlet) offset. For a turbo car where you don't mind a little noise, I would just forget the muffler. Mine is quite quiet with Hooker Aero Chamber. I have 3" out the back on 64 and 68 Darts. 64 Dart has big Jones muffler and resonator at the very end (headers, NA, big cam, kinda loud). Best advice - find a good custom exh shop. They are worth driving, paying, and waiting while they do the work (~1/2 day). Most shops are crap, so get a rec from a trusted hot rodder near where you live. Lou |
|
| Author: | Ssg Pohlman [ Sun May 22, 2016 7:57 am ] |
| Post subject: | |
Mines a d150 but yes run the 3". Mine is 3" all the way and goes thru a cheap autozone thrush turbo. Offset inlet outlet. Nice and quiet when cruising and even when you step on it, still quiet enough that you hear the hx35 sucking and spooling.  cant comment on other sizes, just knew I wasnt going any smaller than turbo outlet all the way.
|
|
| Author: | jcc [ Sun May 22, 2016 12:34 pm ] |
| Post subject: | |
What then is the upper HP/turbo suggested limit for a single 2.5" exhaust? Knowing 3" would always be an improvement, fitting and road clearance are still downsides I need to consider. |
|
| Author: | Dart270 [ Mon May 23, 2016 9:44 am ] |
| Post subject: | |
Probably about 225-250 HP. I'm sure it will depend on turbo size and engine parameters too. You might make plenty of power with 2.5", but you will just make a little more with 3". There are always tradeoffs. Lou |
|
| Author: | jcc [ Mon May 23, 2016 3:15 pm ] |
| Post subject: | |
That was the range I was figuring, thanks. |
|
| Author: | 1974duster kev [ Tue Oct 04, 2016 11:14 am ] |
| Post subject: | |
I had almost identical gains as Lou reported when I changed from 2.5'' to 3'' Mine showed a couple mph gain and lost a couple tenths in the 1/8 mile on 10psi. Kev |
|
| Page 1 of 1 | All times are UTC-07:00 |
| Powered by phpBB® Forum Software © phpBB Limited https://www.phpbb.com/ |
|