Interesting Header + Tune Data Inside

Well I debated doing headers for quite sometime because no cat back sound fit my ear, but I decided to bite the bullet and do it a few weeks ago. Me and a buddy installed the kooks with catted x pipe and it absolutely gave me the sound I was looking for, love it. I drove the car for a few days, monitored afr's and debated doing a tune. I figured what the hell, I came this far might as well go all the way. I had already done a base pull on the dyno on 93 so I already know what the car made stock 465/398 sae. I decided to get a 93 performance tune so I started email/logging process. After the revisions were done, the car felt like it pulled harder and still drove great. It did 485/407 sae on final tune. After a week, I decided to get back on the dyno just to see what the numbers were (all pulls were done on the same dyno in 5th). The only thing I added to the equation was a fuel additive. I strapped the car down and made a pull 490/420 sae with headers, additive and tune. I then reverted back to stock tune, let the car cool and made another pull 490/413 sae. So as you can see, the additive was worth 5 hp/trq and there was no positive knock on the log with stock tune. The car with tune picked up torque/hp across the board, the peaks are just the same. I can feel the difference but I am going to do a comparison at the track or with the cars accelerometer as I think there will be a noticeable difference.

Analyzing other graphs (yes I know all dynos are different) the gains from just a 93 tune versus just headers no tune are close. The other graphs I'm referring to have been in numerous threads on this board. All in all I'm happy I made these changes, I just wanted to share my data with you guys. The only thing left to do now if I choose is corn, which I know will bring big gains. Here's a graph below with all the pulls and the color details are: Red - Stock....Blue - Headers, no additive, stock tune....Green - Headers, additive, stock tune....Orange - Headers, additive, tune....




One example...yes its std but they are close to sea level, so still a good comparison

Very intereting I think you made some spelling errors were you stated the car made 390 on thr stock tune.

So just to recap the car drove and felt fine with headers and green cats on a stock tune and AFRs were in the safe zone?

How is the but of the pants feel with adding the headers does it pull a lot better up high with them now? Do you feel you gained or lost and low rpm torque?

I have been very interested in this combo for some time now.

Thanks for doing this.

Yup sure did, fixed it thanks. The drivability is great and you immediately feel the torque down low and power up top. I did several logs and the car never had positive knock and never leaned out on stock tune. I don't have the green cats, just the tuner cats. You will not regret headers if you do it!!

How long did it take you to install the kooks? Did you have a lift?

~6hrs with a lift :frusty: Drivers side is cheesecake passengerside not so much.

Whose tune and which additive?

It's an AED tune and the additive is ehhhhh, I forget.....It only takes 1oz per 5 gallons though.

Dang man you let me down, I was expecting a smartass one liner from you lol.....It's called Aces IV

chops44 said:

Yup sure did, fixed it thanks. The drivability is great and you immediately feel the torque down low and power up top. I did several logs and the car never had positive knock and never leaned out on stock tune. I don't have the green cats, just the tuner cats. You will not regret headers if you do it!!

Click to expand...

Thanks for this this what Inalways suspected on a stock tune that it would work quiet well with headers. I know there may be a possibilty of check engine for cat efficiency faults.

nice info! car sounds perfect too man:cheers:

oh, and ...

Got any videos of how she sounds?? Catted longtubes and stock catback is what I'm leaning towards as well.