Just wondering who or what exhaust set-up has the fastest timeslip?

Either motor or nitrous pass (not turbo or super-charged- they can cheat with their exhaust, lol)

The exhaust set-up has to be over the axle with and thru the mufflers.

I have a 400sbc with hedman 1 5/8 shorties with single 4" exhaust over the axle thru a flowmaster muffler. My best pass was 11.89 @ 111.

I am sure there are faster 3rd gens than mine .

Post up your timeslip and exhaust set-up!

 

Come on! There has got to be faster cars than me!

 

87_TA went 10.41 at 131 all motor and 9.88 at 142 with a 175 shot I believe but that was on a slightly different setup. No new times with the current motor that runs 10.4's all motor.

Think he has hooker longtubes, custom Y pipe or mufflex Y pipe and a 4" single over the axle dumped. No muffler at the track Sounds amazing and its brutally fast.

I've been 10.63 at 127 with a 383 on a small 150 shot. Single 4" exhaust, hooker longtubes, custom ypipe, Dynomax ultraflo round muffler, and dual tips out the back. FULL exhaust.

 

Hookers? like a 2210?

And then the pipe after the collector on the driverside going underneath the driveshaft to the y-pipe? Whats your ground clearance like?

 

Yep 2210's.

Ground clearance was minimal with the y pipe going under the subframe. I scraped alot and actually ovaled the tubing from bottoming out.

I hugged the crossmember as tight as i could and even had the pipes touching the frame but 3" is just too much pipe to clear.




driver cross over clears well when you run thru the crossmember

 

anybody else has a fast timeslip thru a muffler?

 

I am a procharger guy now, but just two seasons ago when I ran spray, car ran 9.95 @134 with a 383 and 250 shot. With hooker 2210 3" duals bent to single 4" mandrel over axle (mufflex).

 

Have to love the 4 inch lol drags on everything

Hooker super comps
4 inch out the back
Flowmaster 50 series

11.6 on street tires

 

I actually do like the 4" over the axle. Sure it is tight in spots but it works great. I re did the front in mandred 3" and went 8.98 @ 157 with my blower. I think that is good for a full exhaust. I will post some pics soon.

 

I always thought you had plenty of clearance with 4", even going over the axle. I ran a 6" case round muffler in the I pipe region next to the rear end pumpkin and cleared fine and my car is LOW. The ypipe is the problem with longtubes unless you cut the frame up or have a T56/manual with a custom xmember.

 

When you say cutting the frame, where would you cut? Got pics?

 

I dont have pics, but you cut around the subframe around the transmission tunnel/crossmember and box it up. Basically make a notch so you can run the pipes thru there. Some guys make new rails to gain more clearance. If you search for it, you should find pics of setups using cut frames.

 

Not quite as quick as you. Don't have the time slip scanned, but my best is a 12.03 @ 112.6 MPH with the '82 Berlinetta LS1/4L60E. Hawks 1-3/4 x 2.5" long tube headers, custom 2.5" Y-pipe to 3" cat-back, Magnaflow single in/out 3" muffler in the stock location.

Don't have much for pics, this is the custom Y-pipe:




I know the car is an ugly cuss, hope to do something about that soon.




FWIW, I've been driving it to work.

 

any pics?

 

Old combo went 11.50s at 120 ish with a stock chip, slipping trans, street tires and had to lift outa the gas to get trans to upshift..

 

I have an 85 Iroc Z with a 385 afr 195 comp eliminators the same xfi 280 comps cam.T56 The exhaust is an slp dual cat system 1.75 headers to 2.25 Y to a 3 " cat back the muffler is a ? as the slp muffler split many years ago.(walker I think).rpm air gap and a pro systems 4150 based carb.Long winded but interested as you running same cam.Only ran 12.54 so far but was first trip to track but speed was 115.I believe the the exhaust is holding it back now as we went to dyno after the day at track.It put 415 at 5600 and 440 at 4300 I felt that the low peak rpm was indicating the exhaust was not flowing enough? What does you engine peak at?thks

 

On my 383, I think it peaked at 6200.
But that was with 1 5/8 headers and dual 3" open exhaust.

When I had my car on the dyno, i LOST 30twhp by going thru the exhaust(that was single 2 3/4 exhaust)

 

my lil 358. shorties T5 ran 113. 1.8 launching from 2nd. no slicks

 

So what et was that?

And you said you had shorties? 1 5/8 or 1 3/4?
Then how big of exhaust after that? What kind of muffler?

 

1-5/8 Edl 6872 supertrapp cat back.. HSR conv.. the ET was horrible launching from 2nd
the guy I ran against pulled a 1.5 12.7X @ 111

 

Hooker LT's into a 3" Flowmaster American Thunder "catback": 11.50 @ 119

Same setup with a $20 Summit 3" cutout installed in the I-pipe right before the axle = 11.25 @ 121mph.

Those are both motor times. Nitrous times considerably faster...

 

3mph gain is good gain...but not to shabby for a flowmaster 80 series... Thats the fastest i've see thru one so far Was this run on the same day back to back?

 

SO what did you run with nitrous? did you try nitrous thru the mufflers?
How big a shot?

 

Any other fast timeslips running through the mufflers?

What exhaust combo do you have?

I think the gerneral consensus is 1 3/4 hooker LT's with a 3" merge pipe with a single 4" to the back.

Anyone have pics of cutting the frame and making better clearance?

 

Update for this thread.

I have gone 11.16@116 thru the mufflers.
See sig below. That was with an 85hp shot of nitrous.

The last race of the year I'll step up the nitrous and run a sub 11 pass with ease