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Better on an n/a streetport - dual exhaust or single ? Bigger the better or no ?

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Old 03-14-05, 08:16 AM
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Better on an n/a streetport - dual exhaust or single ? Bigger the better or no ?

Looking to get exhaust for my s4 na, still not sure what to use as ive heard all different opinions on it.... i was thinkin of getting the corksport exhaust (3 1/8") but some people tell me go with racing beat or whatever...

is the racing beat exhaust a restriction after 150 whp ? someone told me this...is it true ??

I just dont knowwhat i wanna get i want something that will give me max performance but not hurt my performance in the low rpms and stuff like that

Last edited by wthdidusay82; 03-14-05 at 08:20 AM.
Old 03-14-05, 09:41 AM
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Neither the racing beat nor the Corksport would be a restriction 150 whp, both have been used at well over 300.

The main difference between the 2 is sound and possibly quality. The RB exhaust is quieter then the corksport and is suppose to be built better.

I have SSAutochrome catback which is identical to Corksport, the quality I think is good for the money. I've never seen RB in person though.
Old 03-14-05, 12:21 PM
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Originally Posted by wtfdidusay82

I just dont know what i wanna get i want something that will give me max performance but not hurt my performance in the low rpms and stuff like that
The only way to get close to what you want is trying different exhaust on a chassis dyno. Short primary, long primary and true dual. No matter what anyone tells you, the only way to know is trying different configs. But for the sake of argument I'd recommend the standard Racing Beat header/presilencer and whatever catback you want. If you don't mind loud then the Corksport might be for you. If you have neighbors to deal with then all Racing Beat components is the way to go.

Last edited by MPM; 03-14-05 at 12:25 PM.
Old 03-14-05, 02:21 PM
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Honestly, IMO the CS exhaust is better for performance. Its straight threw and very light. RB is best when your looking to keep the intrigity of the car as with its dual set up. Its still very good and sounds fantastic, people know its there but you won't have to worry about being in 5th gear driving threw town, (as I do with da CRX).
Old 03-14-05, 06:01 PM
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Do not go with a 3" or larger exhaust on a nonturbo street car. You will absolutely lose usable horsepower. I don't need a dyno to tell you that. I've been there and done that and know from experience. Unless you have a large bridge or peripheral port, you don't want one this large. I've personally used all 3 main setups. Long primary, short primary, and true duals. I've also tried them on a stock and a streetport 6 port engine and currently still have a streetported 6 port. My favorite is the long primary. This isn't the easiest on the 2nd gen though unless you like the look of only 1 muffler. All 3 systems are better than stock. I found that the true duals made great low end power from as little as 2000 rpm. I don't know why people say they lose power down low. I didn't. Not by a long shot. They didn't make as much up top as either collected system though. Granted it was still much better than the stock system. The short primary makes great power up top but not as much down low as the dual. The long primary for my uses is the best of both worlds. It makes nice low end power and it continues right up to redline. Who cares if it doesn't make as much any higher than this. I don't drive there. Different porting styles respond differently. If you have a bridge or peripheral port you absolutely must use a collected system to get the most power. There is one very well known rotary builder in the west/northwest who says otherwise but he is flat out wrong. For a stock to a decent streetport, any of these systems will work fine. Some on this forum love the true duals. They were fun but in my opinion they sound like absolute crap. Others love the Harley mated with a lawnmower sound though and wouldn't use anything else. Some here love just using a short primary header. I personally like the long primary system. All 3 work better than stock just don't go too large. You don't need anything over a 2.5" primary sized pipe if it is collected and nothing over a 2" if they stay dual. You'll just lose usable power this way. Everything above is very generalized as this is the general trend of each system based on tuning principles. These do hold true btw. The extent that each is different from the others in terms of powerband is based on several other things such as collector design, muffler design, collector point, etc. I've never had a bad experience with Racing Beat products. Their exhausts are a little heavy but they work very well and don't sound cheap or overly loud.
Old 03-14-05, 06:18 PM
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Alright Rotarygod. Just give me a part number for the long primary for the low end power. Or a name or something for small minds to be able to wrap around. Don't use big words
Old 03-14-05, 06:41 PM
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Originally Posted by rotarygod
Do not go with a 3" or larger exhaust on a nonturbo street car. You will absolutely lose usable horsepower. I don't need a dyno to tell you that. I've been there and done that and know from experience. Unless you have a large bridge or peripheral port, you don't want one this large. I've personally used all 3 main setups. Long primary, short primary, and true duals. I've also tried them on a stock and a streetport 6 port engine and currently still have a streetported 6 port. My favorite is the long primary. This isn't the easiest on the 2nd gen though unless you like the look of only 1 muffler. All 3 systems are better than stock. I found that the true duals made great low end power from as little as 2000 rpm. I don't know why people say they lose power down low. I didn't. Not by a long shot. They didn't make as much up top as either collected system though. Granted it was still much better than the stock system. The short primary makes great power up top but not as much down low as the dual. The long primary for my uses is the best of both worlds. It makes nice low end power and it continues right up to redline. Who cares if it doesn't make as much any higher than this. I don't drive there. Different porting styles respond differently. If you have a bridge or peripheral port you absolutely must use a collected system to get the most power. There is one very well known rotary builder in the west/northwest who says otherwise but he is flat out wrong. For a stock to a decent streetport, any of these systems will work fine. Some on this forum love the true duals. They were fun but in my opinion they sound like absolute crap. Others love the Harley mated with a lawnmower sound though and wouldn't use anything else. Some here love just using a short primary header. I personally like the long primary system. All 3 work better than stock just don't go too large. You don't need anything over a 2.5" primary sized pipe if it is collected and nothing over a 2" if they stay dual. You'll just lose usable power this way. Everything above is very generalized as this is the general trend of each system based on tuning principles. These do hold true btw. The extent that each is different from the others in terms of powerband is based on several other things such as collector design, muffler design, collector point, etc. I've never had a bad experience with Racing Beat products. Their exhausts are a little heavy but they work very well and don't sound cheap or overly loud.

well i want to use the road race header, as far as after that i am not sure what to use ... i dont want to get the racing beat exhaust because i dont exhaust have 1000 bux for it

when u say long primary , u mean to use the collected header ? i want to use the roadrace header. the problem is getting it to flange into a pipe that it will collect into to make it a single exhaust

Last edited by wthdidusay82; 03-14-05 at 06:52 PM.
Old 03-14-05, 07:09 PM
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hey bro I went with a single. I have to say im very happy with my choice is really low in tone yet agressive. I went with 2.5 piping straight through. Racing beat header to rb presilencer to turbo resonator and a straight pipe to a 3inch inlet 3.9 inch oulet tanabe racing medallion muffler. I will later change it to a 2.5 inlet 2.5 outlet racing beat muffler but as of right now i dont have 250 bucks to waste.
Old 03-14-05, 08:22 PM
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If you like the sound of your Medallion muffler, there's no reason to change it. Since the main exhaust pipe is 2.5", the 3" through the muffler is irrelevant. You've already gotten the exhaust tuning out of the way and this won't hurt you. If the main pipe before the muffler were 3", you'd lose low and midrange power.

For a 2nd gen, a long primary system would have to be custom built. You could start with the roadrace header but from there on back it is custom made.

The roadrace header does not collect. If someone only wants a header but not a dual system or a long primary, they'll need the header that collects. While Racing Beat does have one, it isn't on their website. Mazxdatrix has one though. Here's the link.

http://www.mazdatrix.com/getprice.asp?partnum=16130
Old 03-14-05, 08:58 PM
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do you have some kind of picture of this header? I am not 100% sure what it is you have described. I am sure it is simple but I am not sure if it is what I was thinking about doing.

I was thinking about changing from my Bonez superflow set up to a header /silencer set up and hooking it up to my Borla cat back.

not that I really need to change I was jsut really interested in this header that you have that will bring more LOW END POWER.

I could care less about the high end power since I dont ever use that . down low is more important for me, 0-100mph is sufficient. anything after that is useless for me.

thanks
Old 03-14-05, 09:02 PM
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also how does this long primary sound? I dont want lots of noise. my Borla with the BONEZ silencer/high flow cat is loud enough to me. I need to fix some exhaust leaks so I am thinking about changing the entire first half.

I have a good exhaust man that can do the job once I get the header part figured out.

again I dont want lots of noise if that is possible...or leaks....

damn I am tired of leaks
Old 03-14-05, 09:08 PM
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also how does this long primary sound? I dont want lots of noise. my Borla with the BONEZ silencer/high flow cat is loud enough to me. I need to fix some exhaust leaks so I am thinking about changing the entire first half.

I have a good exhaust man that can do the job once I get the header part figured out.

again I dont want lots of noise if that is possible...or leaks....

damn I am tired of leaks
Old 03-14-05, 09:14 PM
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also how does this long primary sound? I dont want lots of noise. my Borla with the BONEZ silencer/high flow cat is loud enough to me. I need to fix some exhaust leaks so I am thinking about changing the entire first half.

I have a good exhaust man that can do the job once I get the header part figured out.

again I dont want lots of noise if that is possible...or leaks....

damn I am tired of leaks
Old 03-14-05, 09:17 PM
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damn computer...sorry for tripple post...

what is the deal? sometimes I sit here for 10 minutes and nothing happens. then I get a proxy error or something. next thing you know I have the same post 3 times.....

sorry
Old 03-14-05, 10:15 PM
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I run a BONEZ silencer/high flow cat, custom 2 1/4" pipe to 2 SuperTraps on my NA. I can adjust the backpressure and noise by adding/removing discs. I am running 9 of 12 possible discs per side and it quiet and seems to help the low end. I ran it with no discs at a track day and I think I sacrificed the acceleration out of the corners too much for a little top end.
Old 03-14-05, 10:17 PM
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i'd be interested to see some dyno's to proove some of the claims.

all im saying is that nobody is right or wrong until they some real numbers to proove what they are saying.....

its way better for education
Old 03-15-05, 03:53 AM
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Which claims? You don't need a dyno to know the rules of how a header system works in regards to tuning and length. They have long since been verified. The shorter the header, the higher up the powerband shifts, the narrower it gets, and the less low end. The shorter headers should also have a higher peak horsepower. Whether or not the engine can rev to this point is another matter however and if matched improperly won't seem that good up top or anywhere else for that matter. This is the uncertainty issue as you may not be able to determine this length without testing. If you know the math you can get very close though. On the other hand they may be matched perfectly and the car may be very fast. The longer the header, the lower the powerband, the wider it is, and the more low end power. Generally it will make less ultimate high end power than a short system but this again depends on exactly what the setup is. A proper long primary vs an improper short primary may still yield the longer one stronger up top. Exactly how much more and where they make more and peak power is totally dependent on the individual system but the general rules of the longer the lower the shorter the higher still apply. It is true though that you never truly know if you've got it right unless you've tested it.

When it comes to dual systems the longer the piping the lower the powerband and lower the peak power level and the shorter the piping the higher the powerband and higher the peak power. The same rules as above apply. The difference is that a collected system is primarily relying on the rules of interference and scavenging whereas the dual systems are using the theory of pipe organ resonance.
Old 03-15-05, 07:46 AM
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Originally Posted by gentlejax2
do you have some kind of picture of this header? I am not 100% sure what it is you have described. I am sure it is simple but I am not sure if it is what I was thinking about doing.

I was thinking about changing from my Bonez superflow set up to a header /silencer set up and hooking it up to my Borla cat back.
http://www.racingbeat.com/FRmazda2.htm

Look at the road race exhaust system for non turbo. Ignore the pieces after the presilencer. On a long primary system you would run the two separate pipes up to one muffler and have them collect right before entering the muffler.

If you have the Borla catback then you won't be able to use it. For your single muffler you really want atleast a 2.5" straight thru design for a mildly ported N/A engine. I know the Borla is straight thru but individually are to small for a single muffler application. Magnaflow makes some good mufflers that many have had good success with.

www.justmagnaflow.com
Old 03-30-05, 09:05 PM
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I have a pretty much all stock 1986 gxl except for a denzo cold air intake and a filter . and an upgrade radiator.. the next thing i want to do is upgrade the exhaust system. I was looking at the
Apexi N1 dual catback
HKS Hi-power duals

with Racing Beat road race headers.. i keep hearing that the RB exhausts and Corkscrew are supposedly really good.. tell my what you think

thanks
Old 03-30-05, 09:37 PM
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Taste great, more filling

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I don't know about losing usable horsepower using big exhaust - I run a 3" from the header down to two 2 1/2" exhaust and I picked up a lot of horsepower and torque over what I had - nice low rumble, too. Yes, it's an NA, but I plan to add a turbo in the future and didn't want to do it all twice. I was worried I would lose hp and that it would sound 'whiney', but it has a NICE low rumble to it, and runs substantially better than the exhaust I had on it when I got it. To each his own though. My whole custom setup, with a 3" high flow cat and 2 2 1/2" mufflers ran less than $200, then another $250 for the install.
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