Borla Exhaust Manifold (Header) for RX8
 

I just wanted to say thanks for all of your help in researching the feasibility of an aftermarket header for the RX8. I am pleased to inform you that we have begun the development of this exhaust manifold and expect to have it ready to ship by March (hopefully).

If you're interested I'll update you with pics as the development continues.

thanks keep us posted.

Definately want some pics !!

I think the Question here is "How Much$ Can we expect to spend?"

My own question is will you be selling a kit (exhaust & headers b/c im still saving up) together for a little bit cheaper than buying seperate?

I'd love to see what your initial design idea looks like now. Start at the beginning and just update us with progress.

I agree... a header + cat-back package deal would sell more of both than you would get separately. (when it's time) posting dynos of stock, cat-back, header, cat-back + header would likely help your cause a lot.

Just my $0.02

Cost and HP gains, please. And did you conquer the port angle issue that was discussed in the last thread about this?

Sweet. I'll buy one.

I would like to know what Mr. Borla thinks about RacingBeat's statment saying "Headers – approximately 4 HP peak power gain." "Mufflers – muffler & connecting pipe - 2-3 HP"

http://www.racingbeat.com/FRmazda4.htm

It would be nice if the vendor can give us more info and defense their products.

Unfortunately, I don't have hp numbers at this time because we're still developing the part. We only started on Monday so I would imagine that it will be at least a week (if not two) before we have a manifold that can be installed on for testing. Furthermore, we'll probably tweak the design for more performance (that's how it usually goes). Same goes for the costing. I can't give you guys a price until we have a finished piece (with a bill of materials, labor times, setup etc.).

I'll update you guys with pics as the development continues and as soon as I have performance numbers (if there are any) and price I'll post them for you as well.

At this point we have some ideas as to how we can improve flow over the stock manifold but we can't be sure it will work until we try it. All we can do is give it a good effort and hopefully create a header that you guys are happy with.

Thanks for your interest and assistance.

I'm a bit confused. Are you asking me to defend Racing Beat? I really don't know how they get their numbers and being that it seems like they are a competitor of ours I don't feel comfortable getting into it. Just to clarify, I work for Borla Exhaust (www.borla.com). Sorry if I was confusing.

keep up informed.

beers

I think what he is trying to say is that he is wondering if you think there is actually more than a 4 hp potential gain out of headers in general on the RX-8. He was just going by a Racing Beat posted claims.

Oops, my bad. I mean it would be nice if you can defend your borla products. Yeah, I know it will make things complicated if you getting into it. Anyways, thank you for the reply.

Yeah, yeah, that's what I meant. :p plus is there actually more than 2-3hp gain out of exhaust in general on the rx-8.

Sorry for all the confusion.

NOT to rehash the earlier discussion (so if you have something to say, P/M me please), but... this statement is what I meant about RB's comments and professionalism in the "RB update thread."

Thanks for clarifying but I'm not sure that I fully understand. When you say "this statement is what I meant", which statement is that? It seems as though you are referring to my statement as that is what you quoted.

I certainly didn't mean to suggest that RB was unprofessional. I was just simply saying that I don't represent RB and can't comment on how they come up with their figures as I have no idea of the process' they use.

Some in the industry feel that manufacturers should not mention competitors so maybe that's why you are suggesting that RB is unprofessional. However, in their defense, they didn't mention anyone specifically. They certainly didn't mention Borla Exhaust so I don't have a problem with it.

Just because I chose not to bash the competition doesn't neccesarily mean that they are unprofessional for doing so.

Thanks for looking out for us though.

The statement that I quote is what I was refering to.

And I in turn did not insinuate that you did. I did not and still do not believe your comments were made with anyone in mind. Nor have I outright said that RB is unprofessional. I have said that overal they seem to be a good company that makes good products, however, I had an issue with the one statement they posted on their website and questions/concerns regarding their release schedule.

Not at all. More like I am looking out for everyone... RB included. Some may say that their statement walks a thin line of what one can get away with... and if myself and several other people construed their comments in a negative light, then we are not the only ones.

I went through that whole thing on the forum in part because there was an issue and I admit I do enjoy a good debate. :p Unfortunately it got out of hand and some people took it personally. I have no vested interest here... it does nothing for me to hurt or help RB. As I said... the interpretation was there and some denied it... I merely sought to explain it and support why.

I don't want to restart this whole discussion on the forum... I'll P/M you the rest of what I've got to say.

Ok guys, let me clarify.

We currently have a production Renesis engine on our engine dyno. With this engine we have tested the stock exhaust, the Borla exhaust, the Racing Beat prototype exhaust, another aftermarket exhaust, and an "open exhaust".

The open exhaust (no muffler on the end of the connecting pipe) produced an additional 4 HP. The Borla performed well and produced about 3 HP as did the RB prototype system. The other aftermarket system produced -1 HP less than the stock system.

Based upon the results of our testing, we are having difficulty understanding some of the MUCH higher HP claims that are being made about exhaust systems that are available. It is certainly possible that their test procedures are different than ours, we can only fairly comment on the test procedures that we utilize and the results that we obtain.

We have also tried 3-4 different header configurations on this same engine. Based on Jim Mederer's knowledge of header design for rotary racing applications, he designed several units of varying lengths and configurations. Unlike power gains that were found on the earlier 79-85 and 86-92 RX-7 applications, similar gains were not realized on the RX-8 and he has yet to observe more than a 3-4 gain. Since initial development has been confined to a "stock" engine, racing applications have yet to be explored.

We have noticed that changes to the exhaust and intake can result in a severe change in sound quality output. To record these changes, we undertake sound test monitoring using an on-board decibel meter after specific component changes. The challenge that the aftermarket will face is to offer these types of power-producing products without adversely sacrificing the sound quality. Of course, this subject is very subjective and the final decision can only rest with the car owner. If the product is primarily intended for a street application for use on a daily-driven car, we will attempt to produce a product that offers a combination of performance improvement with an “acceptable” sound level output.

More later,

Jim Langer
Racing Beat

Nice post, thanks.

What I'm getting out of all of this is that if I spend my hard earned money on intake, exhausts, etc... it should be mainly for the aesthetics and not HP. Which is fine, as long as your expectations are set before you spend the money.

Thanks for posting the info, Mr. Langer.

That's about what I get from it too. Some of the intake mods made thus far do give some hp gain, but word is they can get to be pretty loud...

However... as we were discussing in another thread , I wonder what potential there is in a more complex intake system. Rather than just bolting on an open filter, looking at something simliar to Greddy or a tuned variable length intake as Rotarygod was describing.

Much of our initial work has been with relatively stock engines; access to engines and the parts to rebuild them has been scarce up to this point. Remember, this engine has been available a short time.

The HP improvements that we have found up to this point will certainly be increased by others over time, that is the nature of this business. Someone will ALWAYS find a way to squeeze a few more HP out of a product, but up to a point.

We know guys are smart and can see through much of the marketing hype. Access to chassis dynos allows the consumer to sort through the hype very quickly and prove or disprove a particular claim.

Our initial research showed little promise for much gain with an open-element intake system.... but further testing has revealed some interesting results. BUT, one big factor is the noise increase that this type of design can produce. We have measured a sound level reading of over 90 db in the cockpit with the windows closed!!!! Yikes, for me it was painfully loud. From our opinion we would only consider producing such a product if the power output could be retained, and the noise suppressed.

We have been working on an air-inlet assembly that would be positioned under the front bumper, we will also attempt to incorporate and revised airbox into the design.

Jim Langer

Jim -

Seeing as the stock ECU really runs the engine quite rich, have you guys experimented with intake/exhaust mods with a better air/fuel ratio? I wonder if some of the lack of results could be attributed to an over-rich mixture - as in the engine can breathe better, but it's just drowning in fuel.

Considering that VERY significant power gains have been made in tuning the mixture, I wonder how that, coupled with a good exhaust/intake, will pan out.

Dale

I'd have to check to see if any dynos are posted, however, Canzoomer has said that a car with the RE intake and Borla used in conjunction with his ECU mod seems (i.e. butt dyno) to be putting out significantly more power than his otherwise stock car (ECU mod only).

As I was reading over the comments by Mr. Langer above, this thought occurred to me as well. Perhaps this is another area to look into...

dcfc3s,

You took the words right out of my mouth. ;)

I don't think that we will see any significant gains with bolt on mods until they ECU is tuned appropriately.