HP Loss in a RB Exhaust system ?
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From: CT
Originally posted by areXseven
When I replaced the HKS Super Dragger with the Mag-Flow it opened my exhaust flow tremendously and increased my boost from 10psi to 17 psi at WOT. Now I need a Boost Controller.
When I replaced the HKS Super Dragger with the Mag-Flow it opened my exhaust flow tremendously and increased my boost from 10psi to 17 psi at WOT. Now I need a Boost Controller.
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From: CT
Originally posted by maxcooper
. HKS redesigned the Super Drager 4-5 years ago to make it flow better. Without knowing which Super Drager model was tested, it is hard to evaluate the meaning of those dyno reports.
-Max
. HKS redesigned the Super Drager 4-5 years ago to make it flow better. Without knowing which Super Drager model was tested, it is hard to evaluate the meaning of those dyno reports.
-Max
If i had to guess....i would feel comfortable saying it is the old model. My friend bought the car atleast 4-5 yrs ago and the exhaust was already on the car.
He switched cause he didnt like the looks and sound level of the super dragger. He is an attorney and wanted something alittle more conservative to meet his needs. I think the RB fits the bill perfectly.
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From: Dove le cose sono fatte il vecchio moda il senso
Originally posted by matty
i thing there is something else in the works here to make u go from 10-17 psi
i thing there is something else in the works here to make u go from 10-17 psi
The HKS Super Drager has a 5" exhaust tip/outlet. But in reality, the outlet is only 4" in diameter but tapers into a 5" tip. . The Mag-Flow I installed has dual 3" outlets. So there is a 2" increase in exhaust exit flow with the Mag.
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From: CT
Originally posted by areXseven
I'm not doing a "Houdini" here, This is not rocket science. It is quite evident that the HKS was clogged and/or had a much greater exhaust flow restriction than the MagnaFlow!!. The boost increase DID NOT occur until the HKS went off. Of course, you have to take into account the Mods my engine has. But still, no increase in boost till the Mag was installed.
The HKS Super Drager has a 5" exhaust tip/outlet. But in reality, the outlet is only 4" in diameter but tapers into a 5" tip. . The Mag-Flow I installed has dual 3" outlets. So there is a 2" increase in exhaust exit flow with the Mag.
I'm not doing a "Houdini" here, This is not rocket science. It is quite evident that the HKS was clogged and/or had a much greater exhaust flow restriction than the MagnaFlow!!. The boost increase DID NOT occur until the HKS went off. Of course, you have to take into account the Mods my engine has. But still, no increase in boost till the Mag was installed.
The HKS Super Drager has a 5" exhaust tip/outlet. But in reality, the outlet is only 4" in diameter but tapers into a 5" tip. . The Mag-Flow I installed has dual 3" outlets. So there is a 2" increase in exhaust exit flow with the Mag.
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From: Dove le cose sono fatte il vecchio moda il senso
Originally posted by matty
RIGHT...thats my point! you excluded the clogged. switching a healthy exhaust to another healthy exhaust is not gonna create 7 psi of additional boost...
RIGHT...thats my point! you excluded the clogged. switching a healthy exhaust to another healthy exhaust is not gonna create 7 psi of additional boost...
Originally posted by matty
RIGHT...thats my point! you excluded the clogged. switching a healthy exhaust to another healthy exhaust is not gonna create 7 psi of additional boost...
RIGHT...thats my point! you excluded the clogged. switching a healthy exhaust to another healthy exhaust is not gonna create 7 psi of additional boost...
From his perspective, he switched catbacks and started boosting to 17 PSI. This is mainly do to the fact that he has a midpipe and is having boost creep and/or spikes (probably both at this point).
In his case, I would wager it's what Max said about the older Superdragger exhausts. Ever since I first joined this forum, I've read that the Superdragger was more restrictive than the stock catback.
In areXseven's case, that's probably what kept him from overboosting with the midpipe installed.
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From: Dove le cose sono fatte il vecchio moda il senso
Originally posted by Mahjik
He doesn't know if the exhaust was clogged or not....From his perspective, he switched catbacks and started boosting to 17 PSI. This is mainly do to the fact that he has a midpipe and is having boost creep and/or spikes (probably both at this point)...In areXseven's case, that's probably what kept him from overboosting with the midpipe installed.
He doesn't know if the exhaust was clogged or not....From his perspective, he switched catbacks and started boosting to 17 PSI. This is mainly do to the fact that he has a midpipe and is having boost creep and/or spikes (probably both at this point)...In areXseven's case, that's probably what kept him from overboosting with the midpipe installed.
Last edited by areXseven; Sep 26, 2003 at 10:54 AM.
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From: Dove le cose sono fatte il vecchio moda il senso
Yeah it's either a PFC or a Hi-Flow Main Cat for me. Don't you still need a boost controller to work with the PFC?? Do you do the tuning?? ..Sorry, don't mean to steal the thread.
Originally posted by areXseven
Yeah it's either a PFC or a Hi-Flow Main Cat for me. Don't you still need a boost controller to work with the PFC?? Do you do the tuning?? ..Sorry, don't mean to steal the thread.
Yeah it's either a PFC or a Hi-Flow Main Cat for me. Don't you still need a boost controller to work with the PFC?? Do you do the tuning?? ..Sorry, don't mean to steal the thread.
Originally posted by areXseven
The HKS Super Drager has a 5" exhaust tip/outlet. But in reality, the outlet is only 4" in diameter but tapers into a 5" tip. . The Mag-Flow I installed has dual 3" outlets. So there is a 2" increase in exhaust exit flow with the Mag.
The HKS Super Drager has a 5" exhaust tip/outlet. But in reality, the outlet is only 4" in diameter but tapers into a 5" tip. . The Mag-Flow I installed has dual 3" outlets. So there is a 2" increase in exhaust exit flow with the Mag.
A single 4" tip (HKS) = 12.6 in²
A dual 3" tip (Mag) = 14.1 in²
That's a 12% increase, not 33%, as comparing (3" + 3" vs. 4" ) would imply.
Dave
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From: Dove le cose sono fatte il vecchio moda il senso
Originally posted by dgeesaman
FWIW, the cross-sectional area is what matters.
A single 4" tip (HKS) = 12.6 in²
A dual 3" tip (Mag) = 14.1 in²
That's a 12% increase, not 33%, as comparing (3" + 3" vs. 4" ) would imply.
Dave
FWIW, the cross-sectional area is what matters.
A single 4" tip (HKS) = 12.6 in²
A dual 3" tip (Mag) = 14.1 in²
That's a 12% increase, not 33%, as comparing (3" + 3" vs. 4" ) would imply.
Dave
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From: Dove le cose sono fatte il vecchio moda il senso
Originally posted by Mahjik
A PFC can control boost. However, it cannot stop boost creep *if* you have it.
A PFC can control boost. However, it cannot stop boost creep *if* you have it.
Originally posted by areXseven
What remedies are available, if any, to prevent boost creep??
What remedies are available, if any, to prevent boost creep??
https://www.rx7club.com/forum/showth...threadid=26389
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From: Dove le cose sono fatte il vecchio moda il senso
Originally posted by matty
some people say to port the wastegate.
i would love to know why some cars get it and some dont.
some people say to port the wastegate.
i would love to know why some cars get it and some dont.
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From: Southern California
I really think for what I am trying to accomplish (a little more comfortable sound level, and having the cops stay off my *** ) the dual tip RB is the ticket. Thanks for the advise.
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From: Scotland, Allover the road
I was looking at an Apexi N1 Single tip as my first decent mod. I was told that it was loud and flowed a bit too well, hence boost creep/spike. I like the look of the apexi. A tad rice but at the end of the day my philosophy is to make the car faster than it looks rather than look faster than it is. I take it the RB will cause fewer probs than the N1. I am looking at a boost controller going on with the cat-back anyway.
Basically I need help with this decision.
Basically I need help with this decision.
funny all these replies and still no definate evidence of how much hp is lost with the rb catback. I also don't think it's very quiet at WOT I've heard it with a hfc and it's loud. Definetaly much louder than stock at idle also.
There's no way you went from 10psi to 17psi with just a different catback. There was a serious problem going on there if that's the case. Like a .5 inch pipe welded shut to 4 inch pipe or something. When I put in my silencers in the dual n1 I lose about .5psi and the silencers I bet you are more restrictive than a stock exhaust and without them the dual n1 is probably the best flowing dual tip on the market.
Snook
There's no way you went from 10psi to 17psi with just a different catback. There was a serious problem going on there if that's the case. Like a .5 inch pipe welded shut to 4 inch pipe or something. When I put in my silencers in the dual n1 I lose about .5psi and the silencers I bet you are more restrictive than a stock exhaust and without them the dual n1 is probably the best flowing dual tip on the market.
Snook
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From: Dove le cose sono fatte il vecchio moda il senso
Originally posted by Snook
There's no way you went from 10psi to 17psi with just a different catback. There was a serious problem going on there if that's the case. Like a .5 inch pipe welded shut to 4 inch pipe or something. When I put in my silencers in the dual n1 I lose about .5psi and the silencers I bet you are more restrictive than a stock exhaust and without them the dual n1 is probably the best flowing dual tip on the market. Snook
There's no way you went from 10psi to 17psi with just a different catback. There was a serious problem going on there if that's the case. Like a .5 inch pipe welded shut to 4 inch pipe or something. When I put in my silencers in the dual n1 I lose about .5psi and the silencers I bet you are more restrictive than a stock exhaust and without them the dual n1 is probably the best flowing dual tip on the market. Snook
