I am trying to find out what the fastest someone has been with shorty headers and single exhaust.

I have dyno don headers, 2 1/2 y pipe into 3.5 pipe into 4inch mufflex.

I am trying to decide if it would be worth it go to hooker L/T's w/ 3inch y pipe.

 

i ran a 11.72 with dyno dons headers into a 3 inch exhaust with a 3 inch cutout. I know I can get down into the 11.50's with this setup. How fast are you wanting to go?

 

low 13s all day on heddman shorties and a flowmaster cat back. thats on a pretty mild 383

 

low 12's on mine, at somewhere near 4,000 feet altitude (idaho). flowtech shorty headers, into two 2 1/2 into a single 3 1/2 through a hooker aerochamber.

 

Jerrywho went 11.61 @ 115 with 200 shot

Also...you need to read this thread:


https://www.thirdgen.org/forums/tpi/...lts-added.html

 

I am building a solid roller 406 w/ AFR heads. Power should be around 560-570 according to AFR.

I hope to run mid low 11's.

 

"I am building a solid roller 406 w/ AFR heads. Power should be around 560-570 according to AFR.

I hope to run mid low 11's."

I don't see anything holding you back. Dyno Don's short tube headers will not hold you back. In fact with that much power you will be getting very close to the 10's if not a 10.99.

 

I hope to get to that. I wonder how many passes the 7.5 rear will take.

I am planning on taking off the flowmaster and put a magnaflow muff instead. The magnaflow is suppose to flow way better.

 

hooker maxflow's are the best flowing, the second is the aerochamber.....I'll try to find the muffler flow bench testing sheet and post it back on here.

 

Here is the flow test numbers.....

 

I think you will have that 10 bolt crying uncle in short order. The saving grace is you are running an automatic trans. I think any of the straight through muffler designs such as DynoMax and Magnaflow will get the job done. The bigger the diameter the more CFM.

 

I run MAC 1-5/8" shorties/3" flowmaster pipe with a single 3" in/out Magnaflow welded. Car ran 12.6@114MPH. It's getting longtubes and larger exhasut soon though.

 

12.49 @114mph N/A on normal street tires with old school SLP 1 3/4" shorty's, dual magnaflow cat's and an IMCO 3" cat back

 

There is a thread on the LS1tech board that people have picked up 30RWHP going from the 4inch flowmaster dual outlet to a straight 4in muffler like the magnaflow. That's a bunch.

 

A little of topic but since the subject of 10 Bolt strength was mentioned you might consider one of the LPW Ultimate covers. Adds allot of strength with the bearing cap studs and heavy cover. Here's a link to their site. http://www.lpwracing.com/p_capcovers.asp and here's one for their axle tube brace kits http://www.lpwracing.com/p_axletubebrace.asp

 

I have the rear end girdle. I think it's from T/A. The car has went 7.8's on radial tires with a 1.8 60' and is still together.

 

Does it count if there's a turbo in the mix too? I was using what's in my sig., 1 5/8" shortie headers. I had a 5" cutout after the turbo, but a single 3" pipe with the cutout capped. It still dynoed over 520rwhp with 8psi and the 3" pipe and ran at least a low 10.