Stupid exhaust question Options

[Phat_99CeliGT]

WTF is mandrel bent piping??

[presure2]

mandrel bends are smooth, versus "crush" bends where the bends have like ribs in them, which restricts airflow.

[Phat_99CeliGT]

AHhhhh
so its the same as when they bend the exhaust piping in that machine??

[presure2]

<~~dont know...im really not all that good with that stuff...lol just happen to know the diffrence between the two..

[sirrahtap]

i'm pretty sure they need a better machine to do mandrel bends. i think they stretch them as they are bending them or something. i'm not positive on the process of making them.
but the bends have the same cross sectional area as the straight parts of the piping. in crush bending, the bends have a smaller cross section, which is restrictive

[OCU_Celi]

Mandrel bends don't restrict the air-flow. Crushed bends do, as stated above. If a shop has a machine that bends piping, I really doubt that it's one that does mandrel bends. Every muffler shop has crush bent machines though. It's a heck of a lot cheaper to go crushed, and most people don't know the difference. If you are serious about performance the mandrel bends are the way to go. The Greddy SP exhaust, as well as all their other exhausts, are mandrel bent. The metal on the inside of the curve is thinner and the outside of the curve is thicker, thus air flows smoothly around the curve. Hope that helps.

Nathan

[evolve]

When you bend a pipe using a crush style machine the diameter of the pipe will vary, so at the bend due to the crushing process the diameter of the pipe will become smaller hence restricting the air flow.

Now mandrel pipe bending, im not too sure on the process, but the result is a piping bent to what ever required, whilst maintaining the original desire diameter of piping throught out, including on bends, thus retaining the desired free flow of the pipe.

If you get me, i hope ive explained it clearly, but anyhow, thats pipes!

[Guest_Jason_*]

Either way, your not going to feel a difference in power/performance on our Celica's.

[evolve]

QUOTE (Jason @ Apr 17, 2003 - 4:36 PM)

Either way, your not going to feel a difference in power/performance on our Celica's.

Not necessarily, as if a bend is crushed too much the exhaust could be more restrictive than stock

And the whole idea of buying an aftermarket exhaut is to try to achieve a little more performance, than stock!

[Guest_Jason_*]

If you get a 2.5" crushed vs. a 2.5" mandrel (or any size larger than stock), your not going to feel a difference. Quite honestly with my mandrel, I feel no difference from stock at all.

[Phat_99CeliGT]

well, im not talkin about exhaust work, im wanting to make a new CAI, and i saw where someone used 2.5" piping, and i was just wondering if i could get it at a muffler shop.

[Guest_Matthew_*]

ya you can

or get cheaper pvc pipe. i think that works better





This post has been edited by igotta5S-FEturbo: Apr 17, 2003 - 9:47 PM

[Phat_99CeliGT]

I already have the PVC pipe. Im needing something smaller diameter cause of my hood. The vents hit the CAI.

[Kwanza]

QUOTE (Jason @ Apr 17, 2003 - 6:44 PM)

If you get a 2.5" crushed vs. a 2.5" mandrel (or any size larger than stock), your not going to feel a difference. Quite honestly with my mandrel, I feel no difference from stock at all.

2.5" exhaust is too big for a n/a 4 cylinder anyways...;P You'll actually lose just as much power as crush bent pipes...

[Kwanza]

QUOTE (Phat_99CeliGT @ Apr 17, 2003 - 7:59 PM)

I already have the PVC pipe. Im needing something smaller diameter cause of my hood. The vents hit the CAI.

That's ghetto...pvc pipes...;] I have a 3" mandrel bent steel pipe... ordered it from JC whitney, then again, mine's an ST. For the GT... after looking at the engine bay, it'll be a tight squeeze, but I bet you can get away with a 3" pipe if you're clever. Shoot, I've even designed and made a CAI for a 91 Lude si... Now that's a tightly cramped engine bay... I have pics somewhere. Anyways, for the GT, just off the top of my head, you'll probably need 3 separate bends just to get the right shape. One short one off of the throttlebody, one pointing down away from engine bay, and one off the down, to the driver-side fender. I bet it's doable...I mean, I managed to fit a Civic intake in an 91 MR2...;]