Alright so here's the deal.

My friend belives running a one chamber racing flowmaster will make our cars lose all there back pressure, and so forth.

One of my friends has a 99 z28 auto with a one chamber on it, he used to run 8.5s with his car, now he runs 8.8s. So this is what we are using as "proof" for losing low-end power and the back pressure.

Anyways, so he purchased a one chamber flow master (the first friend, lol) today, and then took it to our local muffler shop, and asked for them to put it on. The muffler shop guy said that our cars will lose low-end power, yadda yadda yadda. So my friend goes back to our local performance shop, returns the one chamber for a two chamber. He gets it installed, and then calls me ranting and raving on how I should cap my cut-out so I won't be like our friend that runs 8.8s, lol. And I should buy a two chamber flowmaster, asap.

I was wondering if all this losing low-end power was true?

Will running a open cut-out frequently or having a one chamber racing flow burn up your 02 simms or the cats?

Soon I will be purchasing hooker LTs and I wanted to run a custom y-pipe after my cats, with no muffler or anything.

It seems to me alot of people do this, that is why I am suspicious on all this power losing, if so many people run without mufflers.

Would running hookers to cats to y-pipe to a two chamber flow, increase or decrease performance?

Wow that might not make any sense what so ever, I didn't know the best way to explain that, lol.

Thank ya, and if you need any thing else on what I would like to know ask!!!

Spud

EDIT: Also info on running true duals wiht the hookers would be appreciated!!!

<small>[ March 04, 2003, 01:42 AM: Message edited by: spud04 ]</small>

 

Just a lil ttt for the post...

I know its long. lol.

spud

 

Come on guys, i need sum hizelp!

yay come one!

spud

 

i know my car is missing its back preassure when my cutout is opened (always opened <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> ) around the town driving, but i don't think back preassure is needed at WOT

 

I'll help you out with this one, but my expierence is not technical but real application. I have a 2 chamber flow with stock manifolds, cats and y. I also have a cutout. My brother-in-law has a z with just the 2 chamber. His is manual, mine is auto. When racing with the cutout closed, we are almost even (I have other mods that he doesn't). With the cutout open I pull away from him. Who cares about low end power on the drag strip when the only app is WOT!!!

 

Having gone this route with three different F bodies with Flowmasters over the years, here's my take. If you are after sound, go with a Flowmaster. One of the deepest sounding out there. If you want power, look into something else. Try Magnaflow or Dynomax. Godd sound and excellent power. Give it a shot! <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

 

Having gone this route with three different F bodies with Flowmasters over the years, here's my take. If you are after sound, go with a Flowmaster. One of the deepest sounding out there. If you want power, look into something else. Try Magnaflow or Dynomax. Godd sound and excellent power. Give it a shot! <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

 

Yeah, so far I think i will do this...

Hooker Lt's
stock cats
custom x-pipe (with cut-outs attached to both sides)
dynomax bullet mufflers

what do ya'll think?

any advice or opinions?

 

Tonight I ran a 8.539, 60' 2.0 with my cut-out open.
with it closed I ran a 8.667, 60' 2.2.

With it closed it is a beast from a stop, the runs were with bald tires so with the cut-out open i had preety good traction, with it closed that thing ripped my tires to the metal!!!

New tires tomorrow... yay!

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by spud04:
<strong> Yeah, so far I think i will do this...

Hooker Lt's
stock cats
custom x-pipe (with cut-outs attached to both sides)
dynomax bullet mufflers

what do ya'll think?

any advice or opinions? </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Why are you going to use stock cats w/ hooker long tube headers? Why waist time with the stock cats? Is there something I don't know?

 

I heard that the LS1 cat is the same as any performance cat that claims to be legal. Acording to a law designed for california the legality of the cat is determined by the amount of air it flows, so technically any cat that is still legal would have the same amount of resisteance. Unless it claims "49 state legal, off-road only in california" I guess its no better than stock. I'd get a test pipe and keep the stock cat for inspection time.

Regarding the setup you got there spud, to put it simple; what you loose in the low end you'll nearly gain back in addition to what you have in the high end. You'll have less torque from a standstill but you'll hain in high-end HP. Thats why with backpressure you can roast like mad but ran a slower 1/8th. With less backpressure your initial torque wont let you boil the tires as wel but when your rolling you'll more than make up for it.

I would just get a electronic cut out... you'd have optimal flow with them open for the track, etc. But you could cruise with the stock muffler or whatever "more subtle" pipes of your choice, and not worry about valve damage and the other sideeffects of running around with little to no backpressure.