Mandrel bends vs. Crush bends
Not much......a lot of factors apply though. I have mandrel bent to the mufflers and crush bent behind. The theory there is that at the track, I can unbolt behind the mufflers and run mandrel bent dumped. Then I can bolt everything back up and run a bit tamer for everyday use. I wouldn't expect more than 3-5 horsepower loss, especially if you use nice large radiuses instead of real tight bends. The money saved would probably justify going crush bent versus mandrel. Now if you are pushing a lot of horsepower, then it might be a larger gap in the loss. But for basic bolt-ons, crush bent is okay. I will eventually upgrade the rear sections to mandrel bent when I pick up some more power and have some more cash.
Crush bends are nasty. 
They not only neck down alot, but also create turbulence. I saw a dyno of a guy awhile back who lost a decent amount of hp going from his catback, to crush bent TD's. I'll never put crush bends on my car.
They not only neck down alot, but also create turbulence. I saw a dyno of a guy awhile back who lost a decent amount of hp going from his catback, to crush bent TD's. I'll never put crush bends on my car. So the stock over the axle pipe is causing a ls1 to lose hp aswards to if you had a manderal pipe in place of the ota ?
Also my muffler shop guy told me that if i were to install a cutout that it would only benefit me from 5-6k rpms ? And that by installing a cutout it would cause turblence and make me lose some hp ? Is that true ?
Also my muffler shop guy told me that if i were to install a cutout that it would only benefit me from 5-6k rpms ? And that by installing a cutout it would cause turblence and make me lose some hp ? Is that true ?
Originally Posted by minesfaster
So the stock over the axle pipe is causing a ls1 to lose hp aswards to if you had a manderal pipe in place of the ota ?
Also my muffler shop guy told me that if i were to install a cutout that it would only benefit me from 5-6k rpms ? And that by installing a cutout it would cause turblence and make me lose some hp ? Is that true ?
Also my muffler shop guy told me that if i were to install a cutout that it would only benefit me from 5-6k rpms ? And that by installing a cutout it would cause turblence and make me lose some hp ? Is that true ?
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I know I picked up a lot of power with the TD's, going from SLP Dual/Dual to this setup. I don't have dyno #'s yet, but I should in the next few weeks. I didn't like using the crush bent, but it fit my budget at the time. My 12.98 run was on TD's that were full crush bent....no mandrel bends anywhere. I changed them after moving here to Arkansas. I doubt I would have seen much better #'s than the ones I got running crush bent as opposed to running full mandrel bends.
Last edited by 99Hawk262; Jan 27, 2006 at 09:59 PM.
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From: England
Originally Posted by loyolacub68
How much HP loss would you expect from crush bending a TD setup vs. mandrel bending?
It all depends, if the crushed bends still exceed the exhaust flow rate then they will have ZERO affect on it. If they don't then they will restrict flow.
Then there's whether they affect the exhaust pressure wave or not, this I 'm not sure about, but I would have thought it to only be a minor concern.
NOt trying to hijack your thread but i ahve a question.
I just had my custom wanna be slp cme cut off and now it is louder kinda sounds like a 5.0... i had a custom dual port d flange on there which made 2 pipes go into 1 when it came out so that way i could have 2 exhaust tips coming out instead of 1. and for a muffler i have a dynomax bullet in the i pipe and now it is just the muffler and the pipe going over the axle then cut off and it sounds totally different. is it because the exhaust is coming out underneath of the car so it is echoing ? i am now concerned if i hook up my true cme tips that i am going to lose this sound. Any advice ?
I just had my custom wanna be slp cme cut off and now it is louder kinda sounds like a 5.0... i had a custom dual port d flange on there which made 2 pipes go into 1 when it came out so that way i could have 2 exhaust tips coming out instead of 1. and for a muffler i have a dynomax bullet in the i pipe and now it is just the muffler and the pipe going over the axle then cut off and it sounds totally different. is it because the exhaust is coming out underneath of the car so it is echoing ? i am now concerned if i hook up my true cme tips that i am going to lose this sound. Any advice ?
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From: San Luis Obispo, CA
Originally Posted by minesfaster
NOt trying to hijack your thread but i ahve a question.
I just had my custom wanna be slp cme cut off and now it is louder kinda sounds like a 5.0... i had a custom dual port d flange on there which made 2 pipes go into 1 when it came out so that way i could have 2 exhaust tips coming out instead of 1. and for a muffler i have a dynomax bullet in the i pipe and now it is just the muffler and the pipe going over the axle then cut off and it sounds totally different. is it because the exhaust is coming out underneath of the car so it is echoing ? i am now concerned if i hook up my true cme tips that i am going to lose this sound. Any advice ?
I just had my custom wanna be slp cme cut off and now it is louder kinda sounds like a 5.0... i had a custom dual port d flange on there which made 2 pipes go into 1 when it came out so that way i could have 2 exhaust tips coming out instead of 1. and for a muffler i have a dynomax bullet in the i pipe and now it is just the muffler and the pipe going over the axle then cut off and it sounds totally different. is it because the exhaust is coming out underneath of the car so it is echoing ? i am now concerned if i hook up my true cme tips that i am going to lose this sound. Any advice ?
You're not doing a very good job at not trying to hijack my thread with your long unrelated question. Start your own thread.
TTT, for anyone else that can help answer my question.
