Headers & exhaust

[edram454]

To each his own. seems to me that there is a reason why GM did not run 3 inch exhaust in the zr1. they probably thought they would have tons of complaints from the customers of the new zr1's complaining as to why the lt1's were smoking them off the line and why they had to rev up like a ricer to make power. My experience with too big of an exhaust proved it to me. In the end, I wound up selling that sweet 1971 mulsanne blue big block coupe because I just was not getting the torque I should have been getting from a healthy 468 big block. I didnt want to spend another 2500 for new smaller diameter side pipes so I sold it. I wish I kinda had it back again. That car was completely restored and won lots of trophies. After that car I stopped being a waxer owner and became just a regular owner.

ed ramos #3028

[bradley]

my black 90 has run 119.47 in the 1/4 with a 21/2 in drgas system and spin tech mufflers . the car only has plenum and injector housing porting headers, and a tune. wish I had the time to switch it to the 92 and see what the difference is.it has a 3 in system with a xpipe and super turbo mufflers callaway porting which is suppose to inc the heads and has only run 118.10 as the best mile an hr .both run about the same et.makes one wonder what is the best way to go ???????

[Schrade]

Originally Posted by bradley

my black 90 has run 119.47 in the 1/4 with a 21/2 in drgas system and spin tech mufflers . the car only has plenum and injector housing porting headers, and a tune. wish I had the time to switch it to the 92 and see what the difference is.it has a 3 in system with a xpipe and super turbo mufflers callaway porting which is suppose to inc the heads and has only run 118.10 as the best mile an hr .both run about the same et.makes one wonder what is the best way to go ???????

So do we!!! That would be VALUABLE info.

Unless Ed has before and after dyno graph info here....................

Does Marc have dyno graphs on his site? I haven't see any info there...

[edram454]

no i dont have dyno graph info on my corvette or my old fox mustang. where i really noticed it was with my big block 71 corvette going to the super-competition hooker sidemounts killed low end torque in a torque monster like a 468 hydraulic cam big block coupe. I did have supertrapp mufflers on my fox mustang and I had something like 20 spacers just to drive around on the street but when I would go racing I would remove all spacers and the cap and run wide open exhaust. my exhaust was 2.5 at the header flange into a 4 inch pipe then into 5 inch super trap mufflers. but at 1200 hp it needed that. My big block corvette definitely felt like it had more torque before the header install. I am not surprised that bradley's 90 ran such a good mile an hour with 2.5 inch exhaust. If he had 3 inch he would probably have a slower 60 time unless he drops the hammer at 5k rpm which would only blow the tires away or chew up some u-joints.

I know that the ex-owner of my car said the few times he went to a track day that a buddy of his who had a 368 lt5 stroker, could not pull away from him on the straights at all and that surprised him. the only time his buddy would pull away a little is when they were coming out of a turn because his friend had 4.10 gears in his z and he had the stock 3.45. Sometimes these cars are like fine wine, some just have the right tweaks and runs like a bat out of hell while some have the wrong combination of tweaks and runs normally but not like one anticipates it to run. On another note, we know that each of these z's were dyno tested before leaving bowling green and I am sure, for whatever unexplained reason, some cars ran better than others which is why they wont release those dyno sheets.

[TomZR1]

I agree with Ed I think 2-1/2 is perfect for the z just wondering if I will lose any torque with headers? I know everyone saying you will get around 20 hp

[TomZR1]

That's why I went with those discontinued hard to find flowmasters force11,plus love the look & I'm sure they'll sound awsome!!!!!

[edram454]

you will not lose torque with the headers. your 2.5 inch exhaust system will have just the right back pressure to insure your torque stays around to do its work. its those big pipe systems that will not supply enough back pressure and the engine having to rev more to produce the backpressure it needs to have the torque. headers and flowmasters without cats and the resonator is perfect. It will last forever and the sound will be great when you are on it and nice when you are just cruising. no tinny sound out of the flowmaster system.

[TomZR1]

I will post pics when done,as for headers can't find anyone to install them here in Michigan once I get em.any one know of anyone in Michigan ?

[TomZR1]

I know what you guys are thinking ,install them your self ,hell no it looks like a pain in the azz,not going to start something that i can't finish.

[TomZR1]

got my exhaust,they look awsome!!!!!!!!