omc8

iTrader: (7)

Anyone have an idea how of a loss .... from the crush.

omc8

iTrader: (7)

No one knows how much of a loss there is using crush bend vs mandrel

LLLosingit

iTrader: (4)

It's not something you can just put a number on, There are way to many variables from one exhaust system to the next and the needs of different engines.

ss454327

iTrader: (10)

I bet you aren't losing anything. A properly tuned exhaust will get smaller as it gets longer so the slight bends at the back are more than likely fine. I would go with cutouts behind the headers (like someone else mentioned) if you are worried about a couple of HP.

omc8

iTrader: (7)

Well , a lot guys think mandrel is the only way to go and if go with crush bend tubing your making a big mistake and will result in huge power loss. But I don't think have any stats to back it up.

omc8

iTrader: (7)

Im not wanting a estimate of power loss so much as a measurement ..... I want to know how much the tubing is crushed from some benders ?

LLLosingit

iTrader: (4)

Did you watch the video I posted on the first page of this thread? I would have thought they would have lost power right away and after everything they did to those headers and it made very little difference. I just installed 3" mandrel exhaust on my truck with cutouts but it's supercharged so the exhaust side needs all the help it can get.

LilJayV10

iTrader: (39)

Engine Masters also did a show on 2.5 v 3 inch exhaust, cheap and expensive mufflers.

IIRC, mufflers were more important in making power than the 1/2 of pipe

omc8

iTrader: (7)

Yes I saw the video , actually viewed it before this thread started, a bit surprising results .

omc8

iTrader: (7)

Ive seen these before also......
Here is Episode 9 2.5 vs 3" 600hp BBC using Magnaflow mufflers Gain 15 tq 13 hp

and Episode 17 Cheap vs Expensive muffler 345 hp SBC Gain 3 tq 13 hp

pdxmotorhead

FWIW, I have a puny jeep Wrangerl 4cyl, I had the motor warmed up and upgraded to a metal cat and a spintec with 2.5 instead of the stock 2.25 pipe, The exhaust change didn't register much on the butt dyno, but the engine reved much better above 3500 and my mileage went up a consistent 2-3 MPG on the highway.. YMMV!

ss454327

iTrader: (10)

If you've ever looked at pipe flow numbers you would see that bends (even mandrel) reduce more flow than you would believe. The exhaust on my s10 is strait through...only change I might make is an H pipe.

omc8

iTrader: (7)

How true , your the first to say that in all the exhaust threads I've ever read ! I have been preaching that for years but most guys just don't get it. That is one of my biggest priorities I have in designing a exhaust system. I try to within the constraints of the app to reduce the amount of degree and number of bends. But most guys get caught up in the mandrel , or size , bling or sound as deciding factors.

LLLosingit

iTrader: (4)

This is where cutouts come in, Most people don't drive it like you stole it all the time but when you want to, just open up the cutouts and let it rip.

My exhaust is setup like this. 1 7/8 headers to 3" collectors to straight thru flowmasters, Right after that are the cutouts that dump before rearend (no room for crossover) Then over the axle to another larger set of straight thru mufflers and very short tail pipes. I haven't ran it yet so I'm not sure how it will sound. I didn't want cutouts right after the headers because I think open headers sound terrible so I put on the mufflers to tone it down a little and then the second set of mufflers to tone it down even further after the cutouts.
I'm running a 6.0 with LSA supercharger/TR6060 in an S10 I'm hoping to be able to quite it down enough to be able to cruise down the highway and not have the noise drive you crazy.

Here is a mock up shot of my exhaust still have some work to do yet.

omc8

iTrader: (7)

Nice work is that an Ext Cab . I take it the other side will mirror the side in the pic.

LLLosingit

iTrader: (4)

Yes, I haven't cleaned up the bottom of the cab yet, You can't see the bed/rear frame in the pic but I brought the frame rails in 6" per side so not much room for mufflers but they will fit with about 2" gap between them.
Still have body work/paint to do.

omc8

iTrader: (7)

Cool you don't see a lot of Step side Xtreme , looks pretty clean from the pics. The rear wheel wells did you widen them or tube it ? Id like to do a RCSB Colorado for a LS swap , but reg cabs are hard to find.

LLLosingit

iTrader: (4)

This was my first try at widening the wheel wheels but I'm happy with how it turned out. I went 8" per side so the floor ribs would line back up when I welded it back together. I did the bed liner myself for a $8 lol , I picked up six cases of two part bed liner for $6 and the gun for $2 at an auction...Nobody bid on the cases because they didn't realize the gun was in another room to be auctioned off later and nobody bid on the gun because they didn't have the two part liner to go with it.

omc8

iTrader: (7)

Nice , good job looks like it could have come from the factory like that . Have you ever seen a Stepside S10 where the bed sides where made flush with the cab like a Fleetside .

LLLosingit

iTrader: (4)

Sorry about hijacking your thread OP.

Here is what I want to copy some day, This was a Chevy Concept Vehicle, No dual wheels...Just large slicks instead!