CoedNaked

I'm not an exhaust pro but I have done some reading on the subject and the just of what I get it is while flow is important i.e. not any restrictions to the pulses of exhaust from the engine which is what a mandrel bent system allows, I also think the overal volume of your exhaust is important. Too big of a pipe gives the exhaust time to cool down which then causes too much backpressure at low RPM's because the cool air slows down the flow of pulses. The only way to then get any power is to speed up the pulses i.e. rev the crap outta the engine which explains why larger pipes aren't always the best. And consider this - you got a pipe that provides minimal restriction to the pulses that is mandrel bent, with less volume so the pulses are free to flow at a wider band of rpm's, or you just picked a larger pipe with more volume and more restriction at the bends. Overall I think I'll take the mandrel bent smaller pipe myself. It'll keep your torque and offer less restriction than the pressure bent stock system if you decide to rev it a little bit assuming you pick the right exhaust size.

Also, why go half assed? If it only takes $100 more to get a few more ponies it's worth it. Look at how much money guys have spent on other mods (K & N FIPK which costs about $250-300 and nets you 3 hp at 4400 RPM?) And also, it doens't hurt to call and ask and get a quote. If he did it in aluminized steel and had it mandrel bent that would save you some money over the 304 S/S I was planning on getting and if he got a cheaper muffler that would also save some money. It could very well work out to just slightly more to have it professionally mandrel bent over pressure bent.

ovrrdrive

I agree with everything you said there...

However I still stand by my comment that it isn't worth the extra hundred or so bucks to get a few horsepower if that is your goal.

If your goal is to do it right and make it look the best it can, and to get it done so it will outlast the truck then the extra several hundred bucks is well justified.

And my comment to use bigger pipe in the bends was in response to you insinuating that the non-mandrel bent pipes are restrictive. A bigger pipe would offset that if you were worried about it.

I guess there is no denying that have a professionally mandrel bent pipe system is the best for everything, but my argument is to wonder if it is really worth it. It will sound the same, last the same, and only put out 2 or 3 more horsepower than a system put together with $20 of pipe and a muffler.

If money is no object I'd pick from any one of the SS pre bent mandrel exhaust systems out there for $600+, but that is not the case. At least not for me. I will do a cheap upgrade to mine when I get around to it and be within .5-1% of the performance of the more expensive systems and sound just as good. And the kicker is that I can do it for about $80.

As I said though, if you have the cash the professional stuff is surely better.

CoedNaked

ovrrdrive -

Lets pretend that we have a 2" mandrel bent system and then we go and get a 2 1/4" pressure bent system. The 2 1/4" pressure bent system's bends reduce the pipe down to the same size as the 2". But you got more volume. The engine STILL has to rev more to get power due to the volume. The pressure bends are also still more restrictive in nature than the 2" mandrel bent system.

Also, if you are going to be throwing in things like headers which further aid in the scavenging effect throughout the RPM band, your total exhaust system is only as good as it's weakest link. If you build a house with all 2 x 10's and you huck a few notches into your 2x 10's the entire 2 x 10 despite the small notch is now a 2 x 8 or 2 x 6 in strength. If you huck in an inferior exhaust system after you spent all this money on headers, intake work, bigger valves, whatever, it defeats the purpose the way I see it.

The reason guys don't get mandrel bent systems is because we don't support the shops that have mandrel benders. As a result we settle. I don't think it's that much more for a mandrel bent system all things considered, either. You just gotta find a shop that makes has one.

ovrrdrive

Not trying to be argumentative here, just trying to understand your line of thinking.

$10 in my eyes is not a lot of money. I'll spend it all day long without batting an eye.

However, if you were a vendor charging me $10 for say, a piece fo gum you'd have to pry it out of my cold, dead fingers. Everything is subjective, and I have no problem paying $10 for something worth $10.

Now, as far as exhaust is concerned, for the sake of argument let's assume a crimp-bent system will run me $200 while an identical system - same pipes and muffler done by the same shop - with mandrel bends will cost $300. Do you honestly think that if I get the $200 system and you get the $300 system that your truck will have more noticeable power than mine?

And if not, how do you justify the extra $100?

Same power, same sound, tip looks the same sticking out the side of the truck... If your truck did 10.80's in the quarter mile I would run back down and spend the extra hundred bucks and beg for forgiveness, but I bet your truck would run exactly the same as mine.

Now, down at the local show and shine people would flock to your truck to see its beautiful exhaust and completely ignore mine...

And that, is the point of the more expensive exhaust. When you break it down, there will be no noticeable performance gain to it, even though the theory and principles of it are rock solid.

As far as performance goes, just how many extra horsepower do you expect to gain from mandrel bends and what impact on the driveability of the truck do you think it would have?

I put a high performance head on my truck that in real life probably gave me a 15-20 horsepower gain over the stock 22re that I had. Honestly, I can barely tell a difference. It runs better that's true, but in daily driving it doesn't feel that much different.

Are you really telling me that having mandrel bends in the same sized pipe will make a noticeable difference in the way the truck drives?