Re: Best Anti reversion / x pipe muffler combo
[Re: FurryStump]
#2975272
10/17/21 10:55 AM
10/17/21 10:55 AM
|
Joined: Mar 2003
Posts: 9,099 Rogue River, OR
Jeremiah
master
|
master
Joined: Mar 2003
Posts: 9,099
Rogue River, OR
|
Low restriction is the name of the game. When I put a 2.25" reproduction exhaust on my GTS I was in a hurry and used the supplied clamps. First good flat footed gear change blew the mufflers off of the intermediate pipes. Keep in mind this was the stock 383 with manifolds, etc. That really got me thinking I needed cut outs.
After the 451 went in I added the cutouts and did some dyno testing. We measured a consistent 25whp gain with no other changes.
Regardless of the tube size, cross pver type etc. your problem will persist until you have a higher flowing set of mufflers. Just my thoughts from some testing we did. Interesting subject!
|
|
|
Re: Best Anti reversion / x pipe muffler combo
[Re: gch]
#2975547
10/18/21 05:39 AM
10/18/21 05:39 AM
|
Joined: Jul 2003
Posts: 5,180 upstate western ny
sogtx
OP
master
|
OP
master
Joined: Jul 2003
Posts: 5,180
upstate western ny
|
Darn I have corresponded with Dr gas in regards to his x kit I was hoping to put his x in .
|
|
|
Re: Best Anti reversion / x pipe muffler combo
[Re: sogtx]
#2975727
10/18/21 03:54 PM
10/18/21 03:54 PM
|
Joined: Aug 2003
Posts: 43,115 Bend,OR USA
Cab_Burge
I Win
|
I Win
Joined: Aug 2003
Posts: 43,115
Bend,OR USA
|
I've done a little exhaust system testing, your 2.5 system is not what I would stay with based on my personal experiences. Car one is my 1969 Dart GTS with a stock stroke and bore 440 motor with a set of the old11.5 to1 TRW pistons and a set of mildly ported big valve 906 heads, TM7 intake and early production Holley 950 HP carb, Hooker 1 7/8 inch fender well A body headers with 2.5 inch pipes through a set of the Thrush 2.5 inch Corvair turbo muffs with a set of 2.5 inch tail pipes exiting in front of the rear wheels. That system was around 7 ft. long and weighed maybe 25 lbs. per side with the muffs, head pipes and tail pipes The car ran from 12.31 to 12.23 at 112.+ MPH in runs in three hours at the old LACR track on a test and tune Friday night with the exhaust system on. I remove the pipes and muffs and made the next run the next morning with about 300 Ft higher difference in the corrected air density, first run with no other changes it ran 11.39 ET at 117.+ MPH That shock the heck out of me but it repeated near those times(11.39 to 11.41 ET) the rest of the day with the open exhaust I got beat in the 4th round and put on a set of 3.5 inch Bullet type muffs hooked directly the header collectors and it slowed down to 11.54 at 116.+ MPH I thought it would pick up by adding collector length, but it didn't My last pump gas car got a 3.0 exhaust system on it with those same Hooker 1 7/8 inch fenderwell headers and a set of the old Magna flow 14x7 inch oval muffs fed with 3.0 inch pipes from the 3.5 inch header collectors with 3.0 side inlet and center outlet size muffs mounted at the rear bumper. That car had a 517 C.I. Pump gas stroker 400 motor in it with a low deck six pack set up with stock type 440 vacuum carbs on it. I raced it here locally at our 1/8 mile Madras track with the exhaust system hooked up, it ran a best of 7.01 ET at 95.3 MPH. I remove the full exhaust system after racing that afternoon and the next run was made at 10.30 AM the next day with less than 200 Ft air density differences, it ran 6.98 at 95.5 MPH with no other changes Not worth taking the exhaust off, huh I would make the entire exhaust system bigger I.D. if I was you
Last edited by Cab_Burge; 10/18/21 03:59 PM.
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
|
|
|
Re: Best Anti reversion / x pipe muffler combo
[Re: sogtx]
#2975984
10/19/21 08:27 AM
10/19/21 08:27 AM
|
Joined: Jan 2003
Posts: 13,354 Marion, South Carolina [><]
an8sec70cuda
I Live Here
|
I Live Here
Joined: Jan 2003
Posts: 13,354
Marion, South Carolina [><]
|
Which dynomax mufflers do you have? Super turbos or Ultraflows? HUGE difference b/t the super turbos and the Ultra Flows. If you have the Super Turbos, the best thing you can do is throw them in the trash if you're trying to make any power.
CHIP '70 hemicuda, 575" Hemi, 727, Dana 60 '69 road runner, 440-6, 18 spline 4 speed, Dana 60 '71 Demon, 340, low gear 904, 8.75 '73 Chrysler New Yorker, 440, 727, 8.75 '90 Chevy 454SS Silverado, 476" BBC, TH400, 14 bolt '06 GMC 2500HD LBZ Duramax
|
|
|
Re: Best Anti reversion / x pipe muffler combo
[Re: sogtx]
#2976390
10/20/21 07:55 AM
10/20/21 07:55 AM
|
Joined: Jan 2003
Posts: 13,354 Marion, South Carolina [><]
an8sec70cuda
I Live Here
|
I Live Here
Joined: Jan 2003
Posts: 13,354
Marion, South Carolina [><]
|
I know some of the TTI kits came w/ the Super Turbos...that's why I asked.
CHIP '70 hemicuda, 575" Hemi, 727, Dana 60 '69 road runner, 440-6, 18 spline 4 speed, Dana 60 '71 Demon, 340, low gear 904, 8.75 '73 Chrysler New Yorker, 440, 727, 8.75 '90 Chevy 454SS Silverado, 476" BBC, TH400, 14 bolt '06 GMC 2500HD LBZ Duramax
|
|
|
|
|