Originally Posted by SSfamilywagon (Post 7541185)

I'm very curious on those trq numbers if you ever get a chance and remember. That is interesting stuff. These things really do need more injector to begin with. I think I've only read one ported head only change on a dyno for a TVS car. I'm just curious what results would be on a m62 car both big and smaller pulley. We all know you'll gain HP for sure, how much just interests me.

That's a good comparison from yours and your buddies TVS set up. Makes me hopeful for the wife's Redline when we finally do the head.


Now that is a nice comparison. It all makes me wonder because lately on the forums and fb pages its all header and dp are a waste of time and no gain on a m62 car. You'll loose trq/flow blah blah. No real dyno of it.

I also thought bolt on's on a stock tune car were a waste because my completely stock Redline is just as fast if not faster then my buddies Cobalt with 3" intake, 3" dp, 2.25 cat back, dual pass, opt b car. Now I'm thinking he sucks at driving haha. I've driven his car and it feels like mine maybe faster. Hpt log times show similar results. Maybe now we'll video a slow as stock race haha.

Anyway I'm just curious guys. Thanks for sharing and info. I'm still leaning on ported head, injectors, tune/e85 as my first mods for my silver car. After a complete stock dyno read out first.

Originally Posted by Staged07SS (Post 7541473)

This is exactly the reason the FB pages are making our community look like a bunch of tards. Full of young dumb kids who think they know it all. Let them think this man. They will always have slow under powered LSJ's.

Originally Posted by matthewj182 (Post 7541513)

I agree with you 100% with the FB pages. I was on the cobalt ss gang page but I left because I couldn't handle the stupidity.

Originally Posted by Staged07SS (Post 7541473)

This is exactly the reason the FB pages are making our community look like a bunch of tards. Full of young dumb kids who think they know it all. Let them think this man. They will always have slow under powered LSJ's.

Originally Posted by InfraRedline (Post 7541587)

I don't even go on any of the regular FB pages besides the IRL one once in a while, and usually only when someone tags me haha. One of my first races over 7 years ago when I was stock with a short ram intake was an LSJ SS with intake and full Hahn header-back exhaust. From a 30 roll we were close until about 50 and then he put 2 cars on me by 100. That's when I learned what exhaust did for these cars...then I bought his header and DP shortly after that when he sold his car :lol:

Oh and after that race we raced from a dig in front of like 40 people and I got the launch and he couldn't catch me :D lol

Originally Posted by SSfamilywagon (Post 7541607)

Agreed. Got one person who dynoed on two different days and different dynos with unexpected results and now has the whole community thinking header/dp is a waste or time and money. SMH. I just know from personal experience doing those mods really made a difference, but again no one has and actual dyno proof.



Lol driver makes all the difference in these cars. See another exhaust test showing it helped. Just like staged said, gonna continue to have a lot of underpowered LSJ cars because people can't put their money in smart places.

Originally Posted by Viperoni (Post 7541740)

What kind of gains would you see from the stock catback to a 2.5" one? Can a pullied M62 take advantage of a 3.0" catback, or is 2.5" the sweet spot?

Originally Posted by Staged07SS (Post 7541744)

3.0" is overkill on an M62 car unless u are spraying.

The stock SS/SC catback is 2.5" for the most part, minus a neck down portion over the rear axle and a tiny inlet to the resonator.

The gains from a catback are due to a straight through muffler, and larger inlet to the resonator.

Gains from a catback on the SS/SC are generally 5 hp or so. The real restriction lies in the exhaust ports in the head, and the downpipe.

Originally Posted by Viperoni (Post 7541758)

I knew about the size reduction to 2.25" before the rear axle, but not the tiny inlet into the resonator..... so there might be a few horses to be had by replacing the resonator inlet and resonator to something that's 2.5" in/out, but probably not worth it.

That's exactly what I needed to know, thanks!

Originally Posted by Staged07SS (Post 7541775)

The inlet to the stock resonator is 2 1/16".

Originally Posted by SSfamilywagon (Post 7542090)

People are so stuck on pipe size being the determining factor for performance that's really half the battle probably even less then that. What you should be more concerned about is cfm flow. Even 2.25 is enough for the m62, its getting rid of the restrictive parts of the exhaust, the factory cat, the resonator and muffler.

Good components like Borla, Corsa, Dynomax are good places to start. People don't realize that in most Magnaflow components the like of the inner diameter of the mufflers or resonator shrink. 2.5 mufflers or resonators usually have 2.25 cores. They also use baffled resonators or louvered ones which hurt flow.

People think they are gaining going to a 3" exhaust, but what's they really get from that is not the piping size, but the mufflers size increase adding more flow. Eventually 2.5 will restrict a high flowing set up, gotta dyno to find out when.

Originally Posted by SSfamilywagon (Post 7542090)

People are so stuck on pipe size being the determining factor for performance that's really half the battle probably even less then that. What you should be more concerned about is cfm flow. Even 2.25 is enough for the m62, its getting rid of the restrictive parts of the exhaust, the factory cat, the resonator and muffler.

Good components like Borla, Corsa, Dynomax are good places to start. People don't realize that in most Magnaflow components the like of the inner diameter of the mufflers or resonator shrink. 2.5 mufflers or resonators usually have 2.25 cores. They also use baffled resonators or louvered ones which hurt flow.

People think they are gaining going to a 3" exhaust, but what's they really get from that is not the piping size, but the mufflers size increase adding more flow. Eventually 2.5 will restrict a high flowing set up, gotta dyno to find out when.