Does any one have a dyno of a stock Bullitt exhaust and of a Bullitt with Longtube headers& H-pipe .
I would like to know if there is still a @25 rwhp difference with the Bullitt's and Longtubes
I had a STOCK 07 Mustang GT Automatic that Dyno'ed at 262 rwhp with just a Dyno tune. I installed a Roush under drive pulley , Slp longtube headers, Slp X-pipes, 4.10 rear end gears, C&L Racer intake and an aluminum driveshaft. Then we dyno tuned again at "298 rwhp" .
So what I was thinking is with the same set up , except for the 4.10's ,would I get over 300 rwhp.
A young lady bought my 07 Mustang Gt and she lives about 10 miles from me. Someday we will race the 2 mustangs, as it sets now I will be look at her tale lights
It's doesn't seem right to be beat by a Mustang that I built and then sold!

 

I would guess those 2 engine mod combinations would yield about the same gain. The auto will dyno a little lower than the 5 speed due to driveline losses (higher with an automatic). Both engines are the same except for the factory tune, harmonic balancer, flywheel and clutch, cold air intake and the exhaust system. Also the heads are different as they have changed to better engineered spark plugs in the Bullitt and engines producer after 12/07. I would recommend going with Kooks longtube headers. I would also think with that setup near sea level with a good driver that high 12 second 1/4 mile passes would be very possible.

 

I've got one. Will post soon.

We gained 19whp after LTs and O/R H at 5800, which is where the dyno stopped. The operator had the cutoff speed at 120mph, instead of 140mph. It's easily safe to say there were and additional 6hp on the top. Stock Bullitt tune.

Also, drag racing S197's, autos are quicker.

 

My bullit stock was 279hp to the rear. After a tune I went to 289hp and i know someone that has a bullitt with a tune and longtube hearders..they clocked 301hp... Hope that answers your question

 

Yes Thank you for your answer!

 

Nice blanket statement. You realize it comes down to the driver, right?

 

HEY! Don't pick on Montoya....HE IS AN EXPERT!

 

I guess you need some S197 education.... http://www.s197forum.com

Even the expert stick drivers can't keep up with those quick shifting autos!

 

Yeah, with the long tube headers (ONLY) how much torque loss under 4000 RPM have you documented?

Because with a stock engine, heads & fuel system the long tube headers give small peak RPM horsepower gains at the expense of low RPM Torque. Most of us aren't going to realize or notice the MAX RPM horsepower gain in our daily driving, yet you will notice the low rpm Torque drop.

Sure the tune helps, but the tune helps without the long tube headers too. The honest black and white gains provided by long tube headers on basically street cars are HIGHLY overrated. Truthfully for the cost and trouble there many more efficient dollar for horsepower modifications available.