57 hp from just exhaust??????
08-21-02, 08:24 AM
#26
RX-7 Bad Ass
iTrader: (55)
Wow. I can't believe a thread on how much horsepower exhaust makes can actually degenerate into this level of dumb.
Anyhow, that said, here's the breakdown -
First off, yes, RB's claims that the full, turbo-back exhaust makes 57 horsepower are legitimate. Bigger, free-flowing exhaust lets the turbo breathe a lot easier, upping boost from about .4 bar or so to about .8 bar. For the metric-challenged, that's 5psi to at least 10psi.
Stock TII's, depending on how well they're running and whether they're an '87-88 or an '89-91, will make around 150-170hp to the ground. That's stock. Actually, I think an old Turbo Magazine project '87 turbo (back in the '80s when the car was new) did like 170 to the ground.
Full exhaust on a TII will easily have you into the 200's. With a cone intake, turbo inlet duct, downpipe/presilencer, boost controller, and a rewired fuel pump, I did 223 to the ground in my 10th Anniversary - that was many mods ago
. And that was still with the stock cat-back.
My old roommate Jay with a '90 turbo did 250 to the ground with a stock turbo, 3" downpipe/midpipe/N1, HKS front mount, 4 720cc injectors, SuperAFC, cone and turbo inlet duct, with boost at about 11psi. That was on a SUPER hot day (upper 90's) and running 10's on the air-fuel across the board (he still didn't have the injectors totally tuned in).
SaabGuy, you need to richen up your mixture between 3000 and 4000 - that's where the motor is really loaded down, and where a LOT of blown motors happen. That's why my old roommate did 720's in the primaries as well - works like a champ. You can also stand to lean out your top end a bit. But, that dyno graph looks great.
Also, the claim of 57 horsepower doesn't just apply to the Racing Beat turbo-back - a good downpipe/midpipe and cat-back will net the same results. The RB exhaust is a work of art - beautifully design, fits like an absolute dream, and is a real bang for the buck. It's too quiet for me, though, and once you go single, you never go back.
On the "rule of thumb" thing - a rule of thumb denotes a hard and fast rule that can always be applied. This is not the case - there's not a specific correlation between boost pressure and horsepower. I can shove 10psi of boost into a motor with an exhaust the size of a straw, or I can do it with a nice 3" exhaust. I can also shove 10psi into a blown motor or a new, tight motor. 1 bar on a stock turbo (which is a bad idea) is nowhere close to the output of a 60-1 at 1 bar - why? The 60-1 is far more efficient, not only heating the intake charge less, but provides much less of a restriction to the exhaust side of the motor. 300 horsepower is EASY with a full turbo setup, and I seriously doubt you can bust 300 with a stock turbo - maybe a hybrid, but definitely not a stock turbo. Unless it's at 16psi and puking its bearings every 30 minutes.
There's your lesson in Makin' Power 101 from the guru for today.
Dale
Anyhow, that said, here's the breakdown -
First off, yes, RB's claims that the full, turbo-back exhaust makes 57 horsepower are legitimate. Bigger, free-flowing exhaust lets the turbo breathe a lot easier, upping boost from about .4 bar or so to about .8 bar. For the metric-challenged, that's 5psi to at least 10psi.
Stock TII's, depending on how well they're running and whether they're an '87-88 or an '89-91, will make around 150-170hp to the ground. That's stock. Actually, I think an old Turbo Magazine project '87 turbo (back in the '80s when the car was new) did like 170 to the ground.
Full exhaust on a TII will easily have you into the 200's. With a cone intake, turbo inlet duct, downpipe/presilencer, boost controller, and a rewired fuel pump, I did 223 to the ground in my 10th Anniversary - that was many mods ago
. And that was still with the stock cat-back.My old roommate Jay with a '90 turbo did 250 to the ground with a stock turbo, 3" downpipe/midpipe/N1, HKS front mount, 4 720cc injectors, SuperAFC, cone and turbo inlet duct, with boost at about 11psi. That was on a SUPER hot day (upper 90's) and running 10's on the air-fuel across the board (he still didn't have the injectors totally tuned in).
SaabGuy, you need to richen up your mixture between 3000 and 4000 - that's where the motor is really loaded down, and where a LOT of blown motors happen. That's why my old roommate did 720's in the primaries as well - works like a champ. You can also stand to lean out your top end a bit. But, that dyno graph looks great.
Also, the claim of 57 horsepower doesn't just apply to the Racing Beat turbo-back - a good downpipe/midpipe and cat-back will net the same results. The RB exhaust is a work of art - beautifully design, fits like an absolute dream, and is a real bang for the buck. It's too quiet for me, though, and once you go single, you never go back
.On the "rule of thumb" thing - a rule of thumb denotes a hard and fast rule that can always be applied. This is not the case - there's not a specific correlation between boost pressure and horsepower. I can shove 10psi of boost into a motor with an exhaust the size of a straw, or I can do it with a nice 3" exhaust. I can also shove 10psi into a blown motor or a new, tight motor. 1 bar on a stock turbo (which is a bad idea) is nowhere close to the output of a 60-1 at 1 bar - why? The 60-1 is far more efficient, not only heating the intake charge less, but provides much less of a restriction to the exhaust side of the motor. 300 horsepower is EASY with a full turbo setup, and I seriously doubt you can bust 300 with a stock turbo - maybe a hybrid, but definitely not a stock turbo. Unless it's at 16psi and puking its bearings every 30 minutes
.There's your lesson in Makin' Power 101 from the guru for today
.Dale
08-21-02, 08:38 AM
#27
I must say that after being on this forum for a while, I am just appalled with some of the replies. I've read. I thought we were a group to learn from one another, share experiences, views etc, but after some on these replies, I personally believe some had better learn some manners.
To Adam Ant, back in the '70's, probably before you were born, myself and a MIT grad were playing around with turbos, and not to go through a lengthy dissertation, but throughout all the testing, the HP did double with each 15 lbs.....I didn't read it on the internet. This isn't rocket science, just some guys discussing reasoning behind increased HP through exhaust modification.
To Adam Ant, back in the '70's, probably before you were born, myself and a MIT grad were playing around with turbos, and not to go through a lengthy dissertation, but throughout all the testing, the HP did double with each 15 lbs.....I didn't read it on the internet. This isn't rocket science, just some guys discussing reasoning behind increased HP through exhaust modification.
08-21-02, 09:32 AM
#28
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Originally posted by likwit rx7
umm i wasnt going to really say anything but why are you soo angry? just because he isnt right? that is no reason to resort to childish insults like "grow up and pass 2nd grade" seriously what is that? he just simply added his opinion of what he thought was right and just because it isnt the same thing you think is right you jump down his throat. he might need to pass 2nd grade or whatever but it is MY OPINION it might defer from yours that you are acting like a 2nd grader
:rolls eyes: the point of this was not to talk noise or anything just to say chill out man! you could have worded things alot nicer that waht you did. ok i said what i had to say and im outta here. sorry for getting off the topic.
umm i wasnt going to really say anything but why are you soo angry? just because he isnt right? that is no reason to resort to childish insults like "grow up and pass 2nd grade" seriously what is that? he just simply added his opinion of what he thought was right and just because it isnt the same thing you think is right you jump down his throat. he might need to pass 2nd grade or whatever but it is MY OPINION it might defer from yours that you are acting like a 2nd grader
:rolls eyes: the point of this was not to talk noise or anything just to say chill out man! you could have worded things alot nicer that waht you did. ok i said what i had to say and im outta here. sorry for getting off the topic.
Because Im a big ******* that hates it when people post things that are wrong?
08-21-02, 09:41 AM
#29
RX-7 Bad Ass
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Originally posted by Turbonut
To Adam Ant, back in the '70's, probably before you were born, myself and a MIT grad were playing around with turbos, and not to go through a lengthy dissertation, but throughout all the testing, the HP did double with each 15 lbs.....I didn't read it on the internet. This isn't rocket science, just some guys discussing reasoning behind increased HP through exhaust modification.
To Adam Ant, back in the '70's, probably before you were born, myself and a MIT grad were playing around with turbos, and not to go through a lengthy dissertation, but throughout all the testing, the HP did double with each 15 lbs.....I didn't read it on the internet. This isn't rocket science, just some guys discussing reasoning behind increased HP through exhaust modification.
Your findings probably apply to the work you did, but not to this scenario. Let's say you double 15psi on the stock turbo to 30psi - you'll be making 400+ horsepower, right? Guess what - you can't get the stock turbo to 30psi, it simply won't spin fast enough and isn't efficient enough to do so, not to mention the bearings start to give out around 12-13 psi. Not to mention it's so horribly inefficient....I could go on and on.
I believe what you're saying, I'm saying that rule, as far as I'm concerned, doesn't apply to RX-7's, and for that matter most street-driven turbocharged cars.
Dale
08-21-02, 09:46 AM
#30
Originally posted by dcfc3s
Wow. I can't believe a thread on how much horsepower exhaust makes can actually degenerate into this level of dumb.
Anyhow, that said, here's the breakdown -
First off, yes, RB's claims that the full, turbo-back exhaust makes 57 horsepower are legitimate. Bigger, free-flowing exhaust lets the turbo breathe a lot easier, upping boost from about .4 bar or so to about .8 bar. For the metric-challenged, that's 5psi to at least 10psi.
Stock TII's, depending on how well they're running and whether they're an '87-88 or an '89-91, will make around 150-170hp to the ground. That's stock. Actually, I think an old Turbo Magazine project '87 turbo (back in the '80s when the car was new) did like 170 to the ground.
Full exhaust on a TII will easily have you into the 200's. With a cone intake, turbo inlet duct, downpipe/presilencer, boost controller, and a rewired fuel pump, I did 223 to the ground in my 10th Anniversary - that was many mods ago. And that was still with the stock cat-back.
My old roommate Jay with a '90 turbo did 250 to the ground with a stock turbo, 3" downpipe/midpipe/N1, HKS front mount, 4 720cc injectors, SuperAFC, cone and turbo inlet duct, with boost at about 11psi. That was on a SUPER hot day (upper 90's) and running 10's on the air-fuel across the board (he still didn't have the injectors totally tuned in).
SaabGuy, you need to richen up your mixture between 3000 and 4000 - that's where the motor is really loaded down, and where a LOT of blown motors happen. That's why my old roommate did 720's in the primaries as well - works like a champ. You can also stand to lean out your top end a bit. But, that dyno graph looks great.
Also, the claim of 57 horsepower doesn't just apply to the Racing Beat turbo-back - a good downpipe/midpipe and cat-back will net the same results. The RB exhaust is a work of art - beautifully design, fits like an absolute dream, and is a real bang for the buck. It's too quiet for me, though, and once you go single, you never go back.
On the "rule of thumb" thing - a rule of thumb denotes a hard and fast rule that can always be applied. This is not the case - there's not a specific correlation between boost pressure and horsepower. I can shove 10psi of boost into a motor with an exhaust the size of a straw, or I can do it with a nice 3" exhaust. I can also shove 10psi into a blown motor or a new, tight motor. 1 bar on a stock turbo (which is a bad idea) is nowhere close to the output of a 60-1 at 1 bar - why? The 60-1 is far more efficient, not only heating the intake charge less, but provides much less of a restriction to the exhaust side of the motor. 300 horsepower is EASY with a full turbo setup, and I seriously doubt you can bust 300 with a stock turbo - maybe a hybrid, but definitely not a stock turbo. Unless it's at 16psi and puking its bearings every 30 minutes.
There's your lesson in Makin' Power 101 from the guru for today.
Dale
Wow. I can't believe a thread on how much horsepower exhaust makes can actually degenerate into this level of dumb.
Anyhow, that said, here's the breakdown -
First off, yes, RB's claims that the full, turbo-back exhaust makes 57 horsepower are legitimate. Bigger, free-flowing exhaust lets the turbo breathe a lot easier, upping boost from about .4 bar or so to about .8 bar. For the metric-challenged, that's 5psi to at least 10psi.
Stock TII's, depending on how well they're running and whether they're an '87-88 or an '89-91, will make around 150-170hp to the ground. That's stock. Actually, I think an old Turbo Magazine project '87 turbo (back in the '80s when the car was new) did like 170 to the ground.
Full exhaust on a TII will easily have you into the 200's. With a cone intake, turbo inlet duct, downpipe/presilencer, boost controller, and a rewired fuel pump, I did 223 to the ground in my 10th Anniversary - that was many mods ago
. And that was still with the stock cat-back.My old roommate Jay with a '90 turbo did 250 to the ground with a stock turbo, 3" downpipe/midpipe/N1, HKS front mount, 4 720cc injectors, SuperAFC, cone and turbo inlet duct, with boost at about 11psi. That was on a SUPER hot day (upper 90's) and running 10's on the air-fuel across the board (he still didn't have the injectors totally tuned in).
SaabGuy, you need to richen up your mixture between 3000 and 4000 - that's where the motor is really loaded down, and where a LOT of blown motors happen. That's why my old roommate did 720's in the primaries as well - works like a champ. You can also stand to lean out your top end a bit. But, that dyno graph looks great.
Also, the claim of 57 horsepower doesn't just apply to the Racing Beat turbo-back - a good downpipe/midpipe and cat-back will net the same results. The RB exhaust is a work of art - beautifully design, fits like an absolute dream, and is a real bang for the buck. It's too quiet for me, though, and once you go single, you never go back
.On the "rule of thumb" thing - a rule of thumb denotes a hard and fast rule that can always be applied. This is not the case - there's not a specific correlation between boost pressure and horsepower. I can shove 10psi of boost into a motor with an exhaust the size of a straw, or I can do it with a nice 3" exhaust. I can also shove 10psi into a blown motor or a new, tight motor. 1 bar on a stock turbo (which is a bad idea) is nowhere close to the output of a 60-1 at 1 bar - why? The 60-1 is far more efficient, not only heating the intake charge less, but provides much less of a restriction to the exhaust side of the motor. 300 horsepower is EASY with a full turbo setup, and I seriously doubt you can bust 300 with a stock turbo - maybe a hybrid, but definitely not a stock turbo. Unless it's at 16psi and puking its bearings every 30 minutes
.There's your lesson in Makin' Power 101 from the guru for today
.Dale
08-21-02, 09:47 AM
#31
Opening up an exhaust for a rotary is the best thing you can do to free up horsepower. I ve heard gains of up to 20hp for an NA when you have an na downpipe and freeflow exhaust so 57 for a turbo seems alot but it could really be about 40hp i would beleive that.
08-21-02, 10:41 AM
#33
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Originally posted by dcfc3s
On the "rule of thumb" thing - a rule of thumb denotes a hard and fast rule that can always be applied. This is not the case - there's not a specific correlation between boost pressure and horsepower. I can shove 10psi of boost into a motor with an exhaust the size of a straw, or I can do it with a nice 3" exhaust. I can also shove 10psi into a blown motor or a new, tight motor. 1 bar on a stock turbo (which is a bad idea) is nowhere close to the output of a 60-1 at 1 bar - why? The 60-1 is far more efficient, not only heating the intake charge less, but provides much less of a restriction to the exhaust side of the motor. 300 horsepower is EASY with a full turbo setup, and I seriously doubt you can bust 300 with a stock turbo - maybe a hybrid, but definitely not a stock turbo. Unless it's at 16psi and puking its bearings every 30 minutes.
There's your lesson in Makin' Power 101 from the guru for today.
Dale
On the "rule of thumb" thing - a rule of thumb denotes a hard and fast rule that can always be applied. This is not the case - there's not a specific correlation between boost pressure and horsepower. I can shove 10psi of boost into a motor with an exhaust the size of a straw, or I can do it with a nice 3" exhaust. I can also shove 10psi into a blown motor or a new, tight motor. 1 bar on a stock turbo (which is a bad idea) is nowhere close to the output of a 60-1 at 1 bar - why? The 60-1 is far more efficient, not only heating the intake charge less, but provides much less of a restriction to the exhaust side of the motor. 300 horsepower is EASY with a full turbo setup, and I seriously doubt you can bust 300 with a stock turbo - maybe a hybrid, but definitely not a stock turbo. Unless it's at 16psi and puking its bearings every 30 minutes
.There's your lesson in Makin' Power 101 from the guru for today
.Dale
Thank you thank you thank you
08-21-02, 12:06 PM
#34
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Originally posted by adamlewis
You really need to learn to read.
In case you didnt notice, I was the first in this thread to say it would yield you ~57 hp.....asshat
Secondly, I was calling your "rule of thumb" crap because its not a rule. Its a "theory" ( do you know what that means? ) of what will happen in "ideal conditions" ( do you know what those are and that they only exist on paper? )
Grow up and pass 2nd grade english before you start attacking people
EDIT: Heres something that ought to keep you busy for a while.
If X increase in boost yields Y amount of hp ( which is your "rule of thumb" ), How is it that a stock FC turbo @ 14.7 PSI makes less power than a T04 @ 14.7 PSI?
Your logic is so flawed its almost sickening. Just because you read something on the internet, doesnt mean its true
You really need to learn to read.
In case you didnt notice, I was the first in this thread to say it would yield you ~57 hp.....asshat
Secondly, I was calling your "rule of thumb" crap because its not a rule. Its a "theory" ( do you know what that means? ) of what will happen in "ideal conditions" ( do you know what those are and that they only exist on paper? )
Grow up and pass 2nd grade english before you start attacking people
EDIT: Heres something that ought to keep you busy for a while.
If X increase in boost yields Y amount of hp ( which is your "rule of thumb" ), How is it that a stock FC turbo @ 14.7 PSI makes less power than a T04 @ 14.7 PSI?
Your logic is so flawed its almost sickening. Just because you read something on the internet, doesnt mean its true
NO FLAMES
Warning #1
Brad
08-21-02, 12:12 PM
#35
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Originally posted by Rotorific
Opening up an exhaust for a rotary is the best thing you can do to free up horsepower. I ve heard gains of up to 20hp for an NA when you have an na downpipe and freeflow exhaust so 57 for a turbo seems alot but it could really be about 40hp i would beleive that.
Opening up an exhaust for a rotary is the best thing you can do to free up horsepower. I ve heard gains of up to 20hp for an NA when you have an na downpipe and freeflow exhaust so 57 for a turbo seems alot but it could really be about 40hp i would beleive that.
Brad
08-21-02, 02:27 PM
#37
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Originally posted by eViLRotor
That dude knows his ****!!!!
That dude knows his ****!!!!
I've been doing this stuff for fun since '95. I've worked on easily 40-50 2nd gens. There's not a lot I don't know about 2nd gens
.Dale
08-21-02, 04:27 PM
#38
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I went from 151rwhp to 197.5rwhp with just the exhaust. And I have a high-flow cat, not a pre-silencer. Until next year, thats all that will be done...I don't want to blow up my engine right now.(Car will be paid off next spring, then I can do whatever the hell I want to it)
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