cutout n catback vs TD

[Raoul-Duke]

ok heres the deal..i have a 01 z28 that has a lid, lt's no cats 3' ory to a pos flowmaster cb...i waaas gonna go true duals but ive heard that due to lack of back pressure that it actually hurts power. people were tellin me unless im pushin 400+ rwhp that i should not go with true duals. bbbut i do NOT want the flowmaster robbin me power as i know it is soo i was thinkin maybe about getting an electric cutout?? what should i do? i was gonna get a pcm tune soo would that help if i were to get true duals?

[nhraformula]

get the true duals and no need for a tune.
any loss of back pressure would be minimal.
you still have stock exhaust manifolds so your car isnt totally free flowing.

[N20LT4]

With your long-tube/no cat setup, I recommend a different cat-back system or TD's over the cut-out.

[Raoul-Duke]

get the true duals and no need for a tune.
any loss of back pressure would be minimal.
you still have stock exhaust manifolds so your car isnt totally free flowing.

you sure about minimal back pressure. i remember even after i got my lt headers on my lt1 z w 3' ory no cat and borla cb it i lost a llllot low end power..also i do have longtube headers on my ls1..still go w the true duals?? whats the difference in hp vs me gettin a cutout w my current setup?

With your long-tube/no cat setup, I recommend a different cat-back system or TD's over the cut-out.

yeah i dont wanna spend money on a diff cb..but you think i wont suffer a lot from low end power loss. i mean theres gonna be like 100% air flow, lol. and im just a bolt on car...

[N20LT4]

you sure about minimal back pressure. i remember even after i got my lt headers on my lt1 z w 3' ory no cat and borla cb it i lost a llllot low end power..also i do have longtube headers on my ls1..still go w the true duals?? whats the difference in hp vs me gettin a cutout w my current setup?


yeah i dont wanna spend money on a diff cb..but you think i wont suffer a lot from low end power loss. i mean theres gonna be like 100% air flow, lol. and im just a bolt on car...

With the true dual system you'll be fine, but I can't say the same about the cut-out. I tried the LT/ORY with cut-out before (on an LT1 car) and it was just too much exhaust - loss of low-end, so I would go for the TD setup!

[Raoul-Duke]

With the true dual system you'll be fine, but I can't say the same about the cut-out. I tried the LT/ORY with cut-out before (on an LT1 car) and it was just too much exhaust - loss of low-end, so I would go for the TD setup!

but if you think ill have a loss of low end w the cutout i would think it would be far greater with true duals..see w my td setup im dumpin it before the rear axle so there wont be a catback. just headers to x-pipe to bullets and turndowns. that, i would think would have far greater low end loss

[N20LT4]

but if you think ill have a loss of low end w the cutout i would think it would be far greater with true duals..see w my td setup im dumpin it before the rear axle so there wont be a catback. just headers to x-pipe to bullets and turndowns. that, i would think would have far greater low end loss

Yeah, you could definitely be right about that. I am not exactly sure, as I have never ran a true dual setup before to compare, but I am sure someone else will chime in here to give you an expert opinion.

[Raoul-Duke]

Yeah, you could definitely be right about that. I am not exactly sure, as I have never ran a true dual setup before to compare, but I am sure someone else will chime in here to give you an expert opinion.

yeah thats just what i would think, i def appreciate your help though

[Raoul-Duke]

de bump

[Speed Psychosis]

i think u'd be fine with true duals. many people run em and don't complain. remember the pipe itself produces a good amount of pressure. open headers might be bad, but evev mufflerless true duals should be fine, as long as you don't have dual 5" piping or anything crazy like that.

[biga0206]

I did LTs, ORY, cut out and picked up around 40 RWHP and 30TQ. It is loud but thats when you just close it up if you dont like it. Either way the true duals or the cut out would work just fine and you shouldn't loose much if any power.

[xzaero0]

ok heres the deal..i have a 01 z28 that has a lid, lt's no cats 3' ory to a pos flowmaster cb...i waaas gonna go true duals but ive heard that due to lack of back pressure that it actually hurts power. people were tellin me unless im pushin 400+ rwhp that i should not go with true duals. bbbut i do NOT want the flowmaster robbin me power as i know it is soo i was thinkin maybe about getting an electric cutout?? what should i do? i was gonna get a pcm tune soo would that help if i were to get true duals?

If you have heared that running TDs has less back pressure and hurts power why would you expect that a cut out that completely opens your exhaust and prolly has even less back pressure would any different?


Go TDs, It sounds so much better than most set ups IMO, and should produce more power with the same mods.

[Hi-Po]

True Duals. They sound great, and will support anything in the near future. Plus, they sound great, did I already say that?

[9t8z28]

you sure about minimal back pressure. i remember even after i got my lt headers on my lt1 z w 3' ory no cat and borla cb it i lost a llllot low end power..also i do have longtube headers on my ls1..still go w the true duals?? whats the difference in hp vs me gettin a cutout w my current setup?


yeah i dont wanna spend money on a diff cb..but you think i wont suffer a lot from low end power loss. i mean theres gonna be like 100% air flow, lol. and im just a bolt on car...

Do you have before and after dyno results? How do you know you lost low end power?

[9t8z28]

ok heres the deal..i have a 01 z28 that has a lid, lt's no cats 3' ory to a pos flowmaster cb...i waaas gonna go true duals but ive heard that due to lack of back pressure that it actually hurts power. people were tellin me unless im pushin 400+ rwhp that i should not go with true duals. bbbut i do NOT want the flowmaster robbin me power as i know it is soo i was thinkin maybe about getting an electric cutout?? what should i do? i was gonna get a pcm tune soo would that help if i were to get true duals?

I am assuming that you are refering to duals dumped @ the axle or TD's over the axle?

[QKSLVR99]

I had the same setup a few yrs back (LTs ORY with flowmaster CB and Cutout) it sounded ok but when I swapped to duals it got rid of that nasty rasp...

As for 400+ for duals , don't worry about that

[0rion]

I run LT's, ORY, and flowmaster on mine. I thought seriously about going to true duals but dumped duals are pretty damn loud. My cutout is loud too but I can close it and run through a flowmaster cb which is fairly quiet compared to most cb's. My setup works for me. The heads/cam made my car considerably louder so that's why I'm leaving my setup as is. Just less hassle from the cops. We have a pretty steep hill right through downtown and going up it with a 3500 stall would make a terrible racket with dumped duals on my car. Attention I can do without.

[niterunnr]

what are td's and ory's

[fxgs]

When I had my SS dyno tuned, we ran it with the cutout closed and open...............with it open I picked up only 4 rwhp but 14 fl/lbs of rwt

[Hi-Po]

what are td's and ory's

TD = True dual set up. Usually a custom fabbed exhaust from headers back. You can have them dumped before the axle or have it ran over the axle out the back.

ORY = Off road Y pipe. Headers, Off Road Y pipe and then with a cat back exhaust system.