What makes an exhaust such as Racing Beat 3" turbo back, for example, superior to an inferior brand? What is it that makes an exhaust system more effective? I mean aren't they all just a set of pipes? I understand how mandrel bends make exhausts better but what other factors are there? I don't mean the width of the pipes either - that is obvious. I ask this because I want to get some idea of how effective the 3" exhaust that my friend has promised to make me from scratch will be. What are the things that he needs to aim for to squeeze every last horse out of it? He is a mechanic and has built V8 race cars before and knows his stuff so it should be okay - I just want to know for my own piece of mind.

 

It's all about workmanship and using the right bits. Use mandrel bends not press bends, smooth bends not sharp ones, MIG or TIG weld for minimal weld bead intrusion, make sure all hangers are study and don't let the system flop around or hang too low or too close to anything, install flanged joints for easier removal, use quality mufflers that are stright through and whose internal perforations don't protrude into the airflow, etc, etc. Just obvious stuff really. With RB, etc you paying for their research (they probably tried dozens of systems), their name and the bolt-on convenience.

 

Racing beat is the best bought one because it is the only 3" exhaust. and the only complete exhuast. all the other cat backs are 2.5" at the flange to meet the stock cat. and the other downpipes are 2.5" at the flange to meet the stock cat.

it wouldn't flow any better then a custom built full 3" one.

 

thanks once again NZ!

 

...and Scott!

 

one more question: what is the stock exhaust width anyway?

 

Also, when you by a RB unit you know that it is not going to melt...

I HIGHLY recommend you use 321 stainless, and you will need to make sure the welder knows how to work with it. Mild steel (in the standard thicknesses) will not last over time.

~Jeremy

 

thats good to know too, ta.

 

IMO, SS exhausts are a waste of money. Sure it'll last forever, but how many people have had to replace a mild steel exhaust they've installed because it rotted out before they sold the car or changed the system for something else?
I installed a 3" aluminised mild steel exhaust on my Cosmo 5 years ago, and according to the current owner, apart from the rear muffler's internal packing (long gone!), it's still in perfect condition.
Sure SS rear mufflers and tips look cool, but I think AMS is fine for the pipes.

 

Yo,


I'll throw my 2 bits in:

Heat.

Rotary exhaust is WAY hotter than a normal piston engine. Racing Beat knows this and builds accordingly. My HKS has held up well. When you go with a name brand Japanese tuner, they've probably done their homework and know that rotaries throw way more heat down those pipes.

KS
1989 GTUs "I think it's like 1700F vs. 1300F or something ridiculous."

 

taking the heat thing into consideration, have you guys heard anything bad about the apex dual N1s?

 

Im having my exhaust built. All 3" mandrel bent, gonna be nice and powerful...may not last as long a RB, but I could buy two complete sytems for what Id pay for one RB system. (though gotta admit...RB makes a NICE system)

 

Might be cheaper to build your own system, but sometimes you have to ask yourself this question. Does it actually make the most hp? RB spent a lot of money and time on researches. I believe in their system more than an el cheapo exhaust that a muffler shop builds.

 

You shouldn’t lump all exhaust shops into one heap. Some are crap, some are amazing. I’ve seen custom exhausts over here that make RB look second rate. I’ve also seen some you wouldn’t give to your worst enemy! It all depends where you go.
Also, the RB system is designed to be quiet. If you don’t mind a bit more noise, it’s not difficult to get a system (off-the-shelf or custom) that will outflow it.

 

I am sure there will be ones that will outflow it (in terms of #), but then we cant just look at it by how much it flows. You also have to look at how much power it actually increases, at what RPM, at which powerband. I am sure a full 3.5 inch exhaust will outflow a RB system in terms of #, but i highly doubt it will get better numbers. There have been a lot of people saying this exhaust is good and that exhaust is good, but none of them have a dyno sheet or a number to back it up. It's like how people say Apex is the best flowing system out there. In a recent dyno test, I saw this Civic Si did worse with an apex cat back compare to a HKS one. There are a lot of factors in it.

 

One nice thing about the RB system is that everything is SS internals. You SHOULDNT be able to melt out the pre-silencers and mufflers on the RB system.