[squish72]

I went with 2" kooks ceramic coated based on all the tests on here that say the the opposite. I may be "leaving" power somewhere but getting rid of the bottleneck that is in the primary cat is the comfort I'm after.

Wish it would warm up so I can install them and LEAVE some black marks on the pavement with all the power I'm able to bring along

[JCurry2885]

Originally Posted by Baker

You already got yours? I ordered mine too and they haven’t shipped yet

Yep got mine 2 days after I ordered them. They are only 2 hours from me, so I suppose I could have drove to get them also.

[Umbriel]

Originally Posted by 18ss376

I do my homework before I listen to anyone.
The dyno & software are just tuning tools.

Real world results = a time slip form the drag strip!

Agreed! I'll be there as soon as it opens back up to see where I am from stock which is 12.20 @ 114 mph. I expect to be 11.70 @ 119 now.

[oldman]

Originally Posted by 18ss376

I do my homework before I listen to anyone.
The dyno & software are just tuning tools.

Real world results = a time slip form the drag strip!

My real world is how my car goes down the street and that is much better with 1 and 7/8.

[biker2k]

how many people have had heat issues with 1 7/8 headers
do I really need heat wrap and if so where...

anybody running headers with no special heat treatments and no problems..

[6spdhyperblue]

Originally Posted by oldman

My real world is how my car goes down the street and that is much better with 1 and 7/8.

Much better? How do you know that?

[oldman]

because I can judge by the way it did not work at all with the smaller header and no cats... LOL. 2" would have been that much worst. How do you know that 2" headers will work better on my DD? Right, test show there is more HP a WOT.
I'm WAY PAST that. In fact I need no HP at all. So 2" headers vs what I have on the car right now. I can tell you FOR SURE, I have the stock OEM spark plug wires on the ride. Try that with 2" headers.


With 1 and 7/8 header the engine produced no power (as in can't move the car) between 850 rpm and 1200 rpm till I put cats in the car. With 2" just off the cuff it would be 850 to 1450 RPM (going by increase in tube volume), that is um 80 percent of my DD performance, also know as "goes down the street".


The factory header is actually good with what dunno 1 and 1/2 with a 2" collector. with no cats the engine would produce HP off idle but it would have a strange harmonic. I have no doubt in my mind that is why GM went with AFM exhaust valves for the auto. I have a M6.


So I've made no contention that the 2" header will be not be faster in the 1/4 mile, I'm sure it will. I have only speculated, and the goes especially for a M6, that real world performance aka goes down the street will be even further reduced and drop like a stone if we are talking a M6 2" headers into a catless 3" exhaust.


I've already stated for my target HP of 709 WHP, a 2" header would have to show 20 WHP for me to give up the drivability, fitment and what I perceive to be more heat in the engine compartment. All enemies of a DD street car. I have already admitted guys going for 1000 engine HP, should only consider 2"..

For some reason there are people that want to contend that all mods must yield max WOT HP. I find it better to build a more flexible package. If I did not do supercharger, I would have done a 416 with 12:00 pistons and a 112 LSA cam, would it produce more HP than a high rev 376? probably not, but it would be a much more livable packaged.

If you don't have a M6, then maybe my observations over years now do not pertain to you and your ride. The M6 is sensitive to flow velocity, I don't know if it is directly related to not having AFM.

[6spdhyperblue]

First I heard of loss of power being catless. Good to know thanks

[oldman]

Let’s just say with no cats or maybe bullets, at small throttle openings, for both FBO and with procharger, the engine wii not produce enough torque to maintain speed from off idle to about 1500 RPM (just checked). You always have to keep the rev up. For me 65mph, low rolling hills was not doable in 6th with no primary cat. 67 was the minimal mph for 6th. With cats it is 7to 10 mph lower, and that holds for each gear.

After checking 1500 rpm the n 5th is 45MPH, this is ok with cats, and 52 without or 1750 RPM.

what mods do you have? I have a ported msd and 103mm tb, but noted an issue ev n with stock tb. Who knows maybe the msd could be also contributing to the issue.

[Umbriel]

Odd I have 2 inch headers and have none of those issues, I even have the stock plug wires still on there *gasp*

Sounds like the ported MSD is the majority of the problem with your issues honestly.

[KingLT1]

There is a header fitment poll thread right in this section. Based on the statistics, Kooks headers show that there is roughly a 80-90% chance you will not have issues. Texas Speed headers show that there is a 60% chance you will.

https://www.camaro6.com/forums/poll....ts&pollid=3854

[Umbriel]

Originally Posted by KingLT1

There is a header fitment poll thread right in this section. Based on the statistics, Kooks headers show that there is roughly a 80-90% chance you will not have issues. Texas Speed headers show that there is a 60% chance you will.

https://www.camaro6.com/forums/poll....ts&pollid=3854

I wonder if that is with the TSP old version or new? I just got mine a few weeks ago and they fit fine but maybe I was lucky?

[KingLT1]

TSP could have very well made some design changes. I have not read of it being mentioned, but I do know as of late there has been a lot less reports of fitment issues.

[Umbriel]

I know I read somewhere they changed something and they were actually out of them for a few weeks waiting on that change and I bought mine right when they were available again. Maybe they fixed all of their issues because mine fit fine, even with stock plugs wires.