I'm on true duals right now and it's loud I MEAN LOUD, dont do it because the likely hood is you'll fry your valves It's to free flowing I've already damaged my valves probabaly because I've been running straight pipes for a long time. Thats why I finally got an exhaust kit.

 

Why would true duals fry your valves? I have a 85 s10 with a 383 with LT's and very short duals with bullets, and I didn't have a problem with valves and I drove that truck for 7 years daily.

 

how does it ruin your valves? i'm curious of this because i'm about to put on my TDs this week and they are short. they dump before where a stock y pipe would be, then they merge back to one before the rear end. if it really ruins my valves i will not put them on.

 

straight pipes will not warp valves, its running open headers, especially on cold days that kills valves.

 

i agree, i did the same on my mustang and my camaro. the mustang had straight pipes, x, then h. the gains from the straight pipes to the H were like 10 or so, then the gains from the H to the X were almost so minimal that it wasnt worth the money....except for the sound.

the camaro i did the same and the result was the same. most people like to justify buying an x over an H by claiming big hp gains, but the fact of the matter is that it wont be enough to notice. it really only affects sound.


true but untrue, i still picked up a few over my lm2 catback with a cutout. either way duals are better

 

the way it ruins valves with straight headers is when you turn you car off and the air is pushed out it makes a vaccum and sucks the outside air in. If its cold then the cold air hitting the heat of the engine will warp the metal.You will not have it with straight pipes. Cherry bomb makes slip on 24" pipes i believe that will go over the header and prevent this.

 

if it merges back to one it isnt true duals...? or am i misunderstanding you?

yea, i knew there wasnt any actual difference between X and H.. so went with what i wanted as far as sound went, reason for the X..

thank you for backing me up, guy didnt have his sheets anyways...

yea, of course you will pick up, but your talking like 2hp, to me it wouldnt be worth it to get a cutout, i would get an electric, so your talking 100 bucks or so for 2 hp... plus i love the sound of my exhaust..

 

I have none on mine, sounds great, very deep rumble (even deeper than the old sbc)

as far as power *shrugs* never compared...and I have cutouts about a foot behind the headers so if I want power those get opened, but the car doesn't feel any stronger with them open

 

The size of the true duals makes a huge difference in the need for an x or an h. If you run a very unrestrictive 3.5" then you would not need a crossover. If you running a smalled diameter exhaust like a 2.5 or 3" then yes a crossover pipe would assist evacuating the exhaust faster. On sprint cars they don't use a cross over...ansd that is the reason. They have such a free flowing exhaust that there is no need for any extra scavenging. On my car I will be running 1 7/8" stepped headers with 3.5" collectors with straight pipes and spintech race mufflers, and I can garauntee that my setup will make more power than a crossover setup

 

if you run a bigger exhaust or no it still has a moment of dead space. its bc one side of the engine fires then the other. So for that split second there is no exhaust in that pipe. Its not about restrictions at all

 

anytime, and yea i had a cutout on my last exhaust which had a y pipe, i did pick up a few but honestly couldnt justify the cost of the cutout for what, maybe 5hp? but u live and learn. i went duals and never looked back and i would recommend the swap to everyone. i have more people tell me my car is the best sounding fbody they have ever heard, i dont have a big head but the compliments speak for themselves i think anyway. definitely worth the money

 

yea, i never was fond of cutouts unless your staying pretty much stock..

i cant count how many people tell me my car is the best sounding car they have ever heard.. and when i drive down the road it breaks necks! haha...

even the people that "try" not to look.. they do!

i love my duals with FM's

 

not to but i had a lady chase me one time in rush hour traffic, in a mini van swerving in and out of traffic, goin thru the medians and all just to catch up to me to hear my car. after she almost wrecks about 5 cars, she passes me hangin out of the car, literally out of the car waving, hootin and hollerin. funny stuff!

duals are by far the best sounding exhaust for fbodys, nuff said

 

so is it a bad idea to put cutouts right after the headers before a y pipe?

 

not necessarily bad.. just not needed..

 

but i thought that would hurt the valves?

 

no, reread up the thread some..

 

okay, so its okay to put cutouts right after the headers but you won't see as much gain in hp as if there was an x pipe?

 

correct..


xpipe will sound better also... but costs more too.. so it depends on budget.

 

no if you have cut outs and you are using then for what its intended for, like a short run down the track you want them open behind the headers. When you are done and about to turn off your car just close your cut outs. See the great thing about a cut out is that all the air doesnt go through the butterfly valve. Air still goes through the regular pipe. This in return will still make a scavenging effect. Enough for the car to run right.