Orange Juice

iTrader: (3)

Well the motor should be on the dyno any day now. It is an ls7 based 440 with TFS 235 heads and a 244 246 114 xer lobe cam with Kooks stepped headers 13/4 to 1 7/8. I currently have the a 3 inch flowtech collector into a 3 inch over the axle to a open cutout that still has the stock muffler and cme tips.
I need to quiet the car down now so one idea I had was to have a custom set of tips made to replace the stock and put them aside. They are starting to crack a little at the flanges. Remove the stock muffler and replace it with ?
Or my second idea which will be the more expensive is true duals exiting just ahead of the rear tire. The issue with this is that the car is pretty low so I would have to go to an oval pipe and I don't know if I could find mufflers that were thin enough to fit.

Redcorvette2000

iTrader: (5)

Are you kidding, you used tfs 235's instead of an ls7 head? Isnt that going to kill your horsepower? Sorry to kind of hijack your thread but i am doing a 440 on my z06 in a few months and was really curious......

Orange Juice

iTrader: (3)

I didn't really want to switch out my intake and injectors for one. Depending on cam and drivetrain some are getting close to 600 rwhp.

MPM IV

iTrader: (3)

Since you already have LS7 heads it dosen't make a lot of sense to switch. I didn't and also went with the 245's. I thought the ls7's were the way to go but the TFS kept being recommended instead. This was two years ago, but I haven't seen a lot of people making much more power. I think the limiting factor is the intake, not the heads.

To the OP, no real idea on making it quieter. I'm using a stock ti catback on a C5 with cutouts. It's pretty quiet for what it is when they are closed, sounds great when they're open.

Orange Juice

iTrader: (3)

Pretty impressive numbers with a 90/90 intake. So the exhaust is dual 3"?

MPM IV

iTrader: (3)

Thanks. I think it's 2.5" actually, but I'm not positive. I always have the cutouts open when I'm runing it. I like the sound closed and had a hard time with the idea of replacing a ti part with a steel one.

LS6427

iTrader: (2)

Why 1 3/4" headers? Thats small.

You should use 1 7/8" stepped to 2".

.

Orange Juice

iTrader: (3)

I had bought the headers for a 347 build. I had asked a couple of engine builders if they would be a problem but was told that they shouldn't.
This isn't a maxium effort build, hoping to be in the low to mid 500 with very streetable manners.
We will see. Motor is suppose to go on the engine dyno today.

Mr Monaro

Going to be one mean cuber nice build by ASE for sure.
CHEEERS

LS6427

iTrader: (2)

There's quite a few C6 Z's around here making between 580-620 RWHP....very streetable cars but aggressive cams. I have yet to see any of them with 1 3/4" headers. I'm almost certain they all have 1 7/8" and the 1 7/8" stepped.
If I get home in time tomorrow there's a gathering and another C6 Z is showing up that supposedly dynoed 605 RWHP last week, we'll see what he has for headers. Later on in the night, we'll see how he runs (roll runs) against the others in real life though.....

.

Orange Juice

iTrader: (3)

I even sent Kooks an email asking about the stepped headers but they never replied. It will be interesting to see how much I lose from flywheel to rear wheel. The motor will be dynoed with a carb and 17/8 headers. Now putting it infront of a 9" rear is going to suck up the hp. I can feel the difference with the new rearend with 400 plus to the rear wheels.

Redcorvette2000

iTrader: (5)

I didnt think anyone even sold 1 3/4 headers for z06's....I thought most people only sold 1 7/8's for those cars......But ive been wrong before.

ramairws6

iTrader: (33)

Ya, that 9 inch is brutal..........

Orange Juice

iTrader: (3)

This is in a Camaro

Redcorvette2000

iTrader: (5)

.....oops

melsie68

iTrader: (8)

In a recent conversation with Kooks I was told 1.875 primaries are good to roughly 725hp. I know Nascar engines are 850+hp and are using 1.875 primaries at 9500rpm. Their headers are tri-y design though which step into usually 2.250 at the first merge and then 3.500 collectors. Food for thought...

dtroike

iTrader: (4)

I just got done building dual 3" over the axle exhaust on my 02 camaro. I used the BMR panhard suport and it is still a very tight fit. I used one borla XR-1 5" on the passenger side and the magna flow I already had in the origanal spot for the driver side pipe. I also used 1 7/8 AR headers and a magna flow x pipe. It sounds awesome and quieter than I expected when cruising. It is a 427 ls1 with TFS 245's and a pretty big hyd cam. It put down 561 rwhp and 535 rwtq with a nice flat curve cut outs closed with 0 miles on motor on pump gas. Generaly the torque under the curve with TFS heads is noticably better than LS7's. The exhaust isn't the hold back, it is the intake.