Highest Power Challenge: 2-Rotor 13B Non-Bridge Non-Peri
05-30-08, 02:22 AM
#151
Junior Member
just to let some people know its more that just a megaphone and if any one can show me a single part that increases peak power by 8-10%at peak and widens the peak power band by more that 3000 rpm you let me know. the gains on pipe vs with out pipe after peak power have been even higher than 10% when you see gains of 20-30+ whp in parts of the power band you wont believe you eyes.
a fairly dramatic example .....a dyno(mustang...add 20whp for dynojet numbers) used by a few south florida scca racers was under the assumtion that a carb would be better than the factory injection manifold and that it was the restriction in these e-prod cars not making competitive power(the z car's down here are said to be making 250whp and the same in tourqe)so on went a extrude honed intake and a big bore t-body(the later part is not leagl but was used as part of the test.the car was tuned and made 189whp@ 8300rpm(209 dynojet) .then i was called in.1/2hr after the 189whp run the legal t-body was back on (smaller butterfly's) and my mid pipe system installed in the 3 inch exhaust and no other changes car was put back on the dyno the shop owner tried to tune the car and was having difficulty getting the car to respond(remember i said before you must throw out all that you know or think you know about n/a rotary tuning with this pipe)at which point i took over tuning this car
after a major change in fuel curve (enough to shift the fuel air ratio 4 full points richer)and timing curve changes (less advance different lead to trail split)
the car was hitting 199whp @7200(219dynojet) and was up to 204whp @ 9200(224dynojet) and still rising
but as this was a back up motor thrown together from used parts unblanced and the weekend before 2 national races we (i.e. the owner)chose not to rev it higher to see the true power peak on the pipe.if you just look at peak numbers(not looking at the difference the big bore t-body may have added) on pipe we made 10more whp 1100rpm lower and at the new peak made 15 whp more total.the real differance is how it changes the curve if you compare the old hp curve with the new you will see that the old curve drops drasticly after 8300 so that by 9000+ its down in the 170whp range thus the gain after peak with the pipe is in excess of 35whp and if reved to 10k plus as the other test car more like 40+whp which on a 200hp car is 20% gain in the higher rpm band ..... sorry for the long post.... but i think it will make people better understand the nature of this pipe.
the reason i brought up jetting with the nikki carb is that on the ida carbs we have seen main jet size's go up 3-5 jet sizes but more dramatic is air jet sizes drop 15 jet sizes to richen up the carb in the higher rpm ranges where this thing really kicks in to keep the motor from burning up i dont know if we can make a nikki run rich enought up top to feed the pipe. if jet sizes can be worked out and required carb mods engineered this pipe will be the must have IT7/ITA part
anyway i have had a long *** day its 3am and i need to get my 3 hr sleep before going back to the shop so read though think about it if i can pry some dyno sheet away from any of the owners ill try to scan them(1 owner went into his file and delete all his hi hp runs because gossip spreads in the scca mazda camp in fl and he does not want his true numbers out there
)
a fairly dramatic example .....a dyno(mustang...add 20whp for dynojet numbers) used by a few south florida scca racers was under the assumtion that a carb would be better than the factory injection manifold and that it was the restriction in these e-prod cars not making competitive power(the z car's down here are said to be making 250whp and the same in tourqe)so on went a extrude honed intake and a big bore t-body(the later part is not leagl but was used as part of the test.the car was tuned and made 189whp@ 8300rpm(209 dynojet) .then i was called in.1/2hr after the 189whp run the legal t-body was back on (smaller butterfly's) and my mid pipe system installed in the 3 inch exhaust and no other changes car was put back on the dyno the shop owner tried to tune the car and was having difficulty getting the car to respond(remember i said before you must throw out all that you know or think you know about n/a rotary tuning with this pipe)at which point i took over tuning this car
after a major change in fuel curve (enough to shift the fuel air ratio 4 full points richer)and timing curve changes (less advance different lead to trail split)
the car was hitting 199whp @7200(219dynojet) and was up to 204whp @ 9200(224dynojet) and still rising
but as this was a back up motor thrown together from used parts unblanced and the weekend before 2 national races we (i.e. the owner)chose not to rev it higher to see the true power peak on the pipe.if you just look at peak numbers(not looking at the difference the big bore t-body may have added) on pipe we made 10more whp 1100rpm lower and at the new peak made 15 whp more total.the real differance is how it changes the curve if you compare the old hp curve with the new you will see that the old curve drops drasticly after 8300 so that by 9000+ its down in the 170whp range thus the gain after peak with the pipe is in excess of 35whp and if reved to 10k plus as the other test car more like 40+whp which on a 200hp car is 20% gain in the higher rpm band ..... sorry for the long post.... but i think it will make people better understand the nature of this pipe.
the reason i brought up jetting with the nikki carb is that on the ida carbs we have seen main jet size's go up 3-5 jet sizes but more dramatic is air jet sizes drop 15 jet sizes to richen up the carb in the higher rpm ranges where this thing really kicks in to keep the motor from burning up i dont know if we can make a nikki run rich enought up top to feed the pipe. if jet sizes can be worked out and required carb mods engineered this pipe will be the must have IT7/ITA part
anyway i have had a long *** day its 3am and i need to get my 3 hr sleep before going back to the shop so read though think about it if i can pry some dyno sheet away from any of the owners ill try to scan them(1 owner went into his file and delete all his hi hp runs because gossip spreads in the scca mazda camp in fl and he does not want his true numbers out there
)
05-30-08, 09:39 AM
#153
Respecognize!
so let me think for a second. From what i know about fluids, i can think of the basic formula:
Mass Flow = (Density x Velocity x Area) [ M = DVA ]
Mass flow is usually a constant due to the "conservation of mass". Air is compressible but the fluctuation of density due to temperature, pressure, etc isn't going to be too great. The heat will be trying to expand the air, the pressure will be trying to compress it.
so that means velocity and area are inverse proportional. If the velocity increases, the area must decrease and visa versa. So if you decrease the area of the exhaust port, the velocity must increase. If the velocity is high enough, then the exhaust gases will be pulled from the engine
Mass Flow = (Density x Velocity x Area) [ M = DVA ]
Mass flow is usually a constant due to the "conservation of mass". Air is compressible but the fluctuation of density due to temperature, pressure, etc isn't going to be too great. The heat will be trying to expand the air, the pressure will be trying to compress it.
so that means velocity and area are inverse proportional. If the velocity increases, the area must decrease and visa versa. So if you decrease the area of the exhaust port, the velocity must increase. If the velocity is high enough, then the exhaust gases will be pulled from the engine
05-30-08, 10:09 AM
#154
^Correct! The key in sizing intakes or exhausts properly is to only go as large as you need to and no larger. Velocity is king but only to a certain point. Once you go above this point, you lose power. If you are below this point, you are losing power. The key is to size everything for your intended peak power spot.
This of course is ignoring the effects of megaphones and diverging cone merge collectors on acoustic benefits in exhausts but from a primary pipe standpoint, it's absolutely true.
This of course is ignoring the effects of megaphones and diverging cone merge collectors on acoustic benefits in exhausts but from a primary pipe standpoint, it's absolutely true.
05-30-08, 10:19 AM
#155
Take a look at the expansion chamber that ISC uses on their race exhausts. Scroll down the page halfway and look on the left. I suspect this is similar to what he is using. It's an old trick.
http://www.iscracing.net/2nd_Gen_Parts.htm
http://www.iscracing.net/2nd_Gen_Parts.htm
05-30-08, 12:04 PM
#156
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Take a look at the expansion chamber that ISC uses on their race exhausts. Scroll down the page halfway and look on the left. I suspect this is similar to what he is using. It's an old trick.
http://www.iscracing.net/2nd_Gen_Parts.htm
http://www.iscracing.net/2nd_Gen_Parts.htm
i dunno, maybe stock intake, needs a different sized thingee?
05-30-08, 12:39 PM
#157
Old [Sch|F]ool
The biggest problem I had running a Nikki was being able to pull fuel out at the top end. An open plenum carb spacer worked TOO well but I recall running fuel pressure in the 1.5psi range. This on a mild street ported 12A (definite 5500rpm "starting point".
05-30-08, 01:00 PM
#158
I was about to test one on the 'All Motor' race car but then the accident happened. Most of his testing were done on stock or near stock motors. Would have been nice to see what the effects would have been on a high output PP motor.
One problem he was having was that on the carb cars it was difficult to get the tune correct vs say the efi cars where you could actually target the AFR's at certain rpms because of the effects the chamber was having. All I'm going to say is that if the carbs could have compensated for manifold pressure without effecting the low and midrange they would have worked also. I've been sworn not to reveal too much info because this guy actually does a lot of racing and have a lot of cars he's responsible for.
05-30-08, 01:07 PM
#159
just to let some people know its more that just a megaphone and if any one can show me a single part that increases peak power by 8-10%at peak and widens the peak power band by more that 3000 rpm you let me know. the gains on pipe vs with out pipe after peak power have been even higher than 10% when you see gains of 20-30+ whp in parts of the power band you wont believe you eyes.
a fairly dramatic example .....a dyno(mustang...add 20whp for dynojet numbers) used by a few south florida scca racers was under the assumtion that a carb would be better than the factory injection manifold and that it was the restriction in these e-prod cars not making competitive power(the z car's down here are said to be making 250whp and the same in tourqe)so on went a extrude honed intake and a big bore t-body(the later part is not leagl but was used as part of the test.the car was tuned and made 189whp@ 8300rpm(209 dynojet) .then i was called in.1/2hr after the 189whp run the legal t-body was back on (smaller butterfly's) and my mid pipe system installed in the 3 inch exhaust and no other changes car was put back on the dyno the shop owner tried to tune the car and was having difficulty getting the car to respond(remember i said before you must throw out all that you know or think you know about n/a rotary tuning with this pipe)at which point i took over tuning this car
after a major change in fuel curve (enough to shift the fuel air ratio 4 full points richer)and timing curve changes (less advance different lead to trail split)
the car was hitting 199whp @7200(219dynojet) and was up to 204whp @ 9200(224dynojet) and still rising
but as this was a back up motor thrown together from used parts unblanced and the weekend before 2 national races we (i.e. the owner)chose not to rev it higher to see the true power peak on the pipe.if you just look at peak numbers(not looking at the difference the big bore t-body may have added) on pipe we made 10more whp 1100rpm lower and at the new peak made 15 whp more total.the real differance is how it changes the curve if you compare the old hp curve with the new you will see that the old curve drops drasticly after 8300 so that by 9000+ its down in the 170whp range thus the gain after peak with the pipe is in excess of 35whp and if reved to 10k plus as the other test car more like 40+whp which on a 200hp car is 20% gain in the higher rpm band ..... sorry for the long post.... but i think it will make people better understand the nature of this pipe.
the reason i brought up jetting with the nikki carb is that on the ida carbs we have seen main jet size's go up 3-5 jet sizes but more dramatic is air jet sizes drop 15 jet sizes to richen up the carb in the higher rpm ranges where this thing really kicks in to keep the motor from burning up i dont know if we can make a nikki run rich enought up top to feed the pipe. if jet sizes can be worked out and required carb mods engineered this pipe will be the must have IT7/ITA part
anyway i have had a long *** day its 3am and i need to get my 3 hr sleep before going back to the shop so read though think about it if i can pry some dyno sheet away from any of the owners ill try to scan them(1 owner went into his file and delete all his hi hp runs because gossip spreads in the scca mazda camp in fl and he does not want his true numbers out there )
a fairly dramatic example .....a dyno(mustang...add 20whp for dynojet numbers) used by a few south florida scca racers was under the assumtion that a carb would be better than the factory injection manifold and that it was the restriction in these e-prod cars not making competitive power(the z car's down here are said to be making 250whp and the same in tourqe)so on went a extrude honed intake and a big bore t-body(the later part is not leagl but was used as part of the test.the car was tuned and made 189whp@ 8300rpm(209 dynojet) .then i was called in.1/2hr after the 189whp run the legal t-body was back on (smaller butterfly's) and my mid pipe system installed in the 3 inch exhaust and no other changes car was put back on the dyno the shop owner tried to tune the car and was having difficulty getting the car to respond(remember i said before you must throw out all that you know or think you know about n/a rotary tuning with this pipe)at which point i took over tuning this car
after a major change in fuel curve (enough to shift the fuel air ratio 4 full points richer)and timing curve changes (less advance different lead to trail split)
the car was hitting 199whp @7200(219dynojet) and was up to 204whp @ 9200(224dynojet) and still rising
but as this was a back up motor thrown together from used parts unblanced and the weekend before 2 national races we (i.e. the owner)chose not to rev it higher to see the true power peak on the pipe.if you just look at peak numbers(not looking at the difference the big bore t-body may have added) on pipe we made 10more whp 1100rpm lower and at the new peak made 15 whp more total.the real differance is how it changes the curve if you compare the old hp curve with the new you will see that the old curve drops drasticly after 8300 so that by 9000+ its down in the 170whp range thus the gain after peak with the pipe is in excess of 35whp and if reved to 10k plus as the other test car more like 40+whp which on a 200hp car is 20% gain in the higher rpm band ..... sorry for the long post.... but i think it will make people better understand the nature of this pipe.
the reason i brought up jetting with the nikki carb is that on the ida carbs we have seen main jet size's go up 3-5 jet sizes but more dramatic is air jet sizes drop 15 jet sizes to richen up the carb in the higher rpm ranges where this thing really kicks in to keep the motor from burning up i dont know if we can make a nikki run rich enought up top to feed the pipe. if jet sizes can be worked out and required carb mods engineered this pipe will be the must have IT7/ITA part
anyway i have had a long *** day its 3am and i need to get my 3 hr sleep before going back to the shop so read though think about it if i can pry some dyno sheet away from any of the owners ill try to scan them(1 owner went into his file and delete all his hi hp runs because gossip spreads in the scca mazda camp in fl and he does not want his true numbers out there
)I see you're revealing secrets now!
If I had taken the time to read I would have seen your post and not waste time with my post above!
Carry on maestro!
05-30-08, 01:17 PM
#160
Lives on the Forum
Power is work done over time. Accelerating a Dynojet roller requires a known amount of work, and the faster you can accelerate it the more power you're making. This is a direct measurement of power.
Now since HP and torque are directly linked, it really doesn't matter what you measure, as long as you know the RPM precicely you can calculate the one from the other, and it's equally important to know it going either way.
Now since HP and torque are directly linked, it really doesn't matter what you measure, as long as you know the RPM precicely you can calculate the one from the other, and it's equally important to know it going either way.
05-30-08, 02:04 PM
#161
^Correct! The key in sizing intakes or exhausts properly is to only go as large as you need to and no larger. Velocity is king but only to a certain point. Once you go above this point, you lose power. If you are below this point, you are losing power. The key is to size everything for your intended peak power spot.
This of course is ignoring the effects of megaphones and diverging cone merge collectors on acoustic benefits in exhausts but from a primary pipe standpoint, it's absolutely true.
This of course is ignoring the effects of megaphones and diverging cone merge collectors on acoustic benefits in exhausts but from a primary pipe standpoint, it's absolutely true.
We have tested at least four different intake setups before arriving at our last combo and I'm not going to get into exhaust designs to match the intake combos. I don't think I have even figured out the best exhaust setup as of yet. It's a never ending story of testing.
05-31-08, 04:29 PM
#163
You can increase velocity on the exhaust port side of the megaphone by running rich and retarded so that you can INCREASE velocity in the larger post megaphone section due to the rapidly expanding exhaust gasses and the pressure differential between the sides of the megaphone.
Due the class rules allow for an exhaust leak at the large end of the megaphone?
I suspect you have just pinpointed the choke point of power on the motor is the exhaust port and found a way to make it flow more.
Exhaust port shape developed with the aid of a flow bench...
Due the class rules allow for an exhaust leak at the large end of the megaphone?
I suspect you have just pinpointed the choke point of power on the motor is the exhaust port and found a way to make it flow more.
if any one can show me a single part that increases peak power by 8-10%at peak and widens the peak power band by more that 3000 rpm you let me know.
05-31-08, 06:49 PM
#164
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what do you guys think about the RB true dual system? how much power do you think it would create over a RB street header/presilencer+catback? i'm still stuck a lil in piston world so I'm not quite sure how benificial this would be...
05-31-08, 07:50 PM
#165
I think the RB dual will work well for a broad power band with the stock intake manifold but it would lose power over the RB header/silencer and catback in the high rpm areas you need for performance driving.
The true dual works kinda like the stock exhaust manifold in that it will allow more of the high pressure exhaust wave to exit the intake port when it opens to supercharge the intake on the opposite port- good for low rpm power if you have the stock DEI manifold.
At higher rpms where you want power for performance driving the negative exhaust pressure wave from the header collector will make more power even with the stock DEI intake manifold and much more with a short race manifold.
The true dual works kinda like the stock exhaust manifold in that it will allow more of the high pressure exhaust wave to exit the intake port when it opens to supercharge the intake on the opposite port- good for low rpm power if you have the stock DEI manifold.
At higher rpms where you want power for performance driving the negative exhaust pressure wave from the header collector will make more power even with the stock DEI intake manifold and much more with a short race manifold.
06-03-08, 11:01 AM
#166
This is a little off topic but just wanted to let everyone know that Im sell 3 complete 2nd gens for a good trade or a good price. Pm me for any questions.
But back on topic, Im about to get my motor ported by jim from jpr. got the exhaust and Im going to be using a turboII intake, just need a standalone. Im still undecided on rather I should use it in a first gen because of the weight. But hopefully with a little help from my friend, I would be very happy if i can break the 200rwhp mark. Also curious if anyone else is getting started on this challenge and what setup are you going with?
But back on topic, Im about to get my motor ported by jim from jpr. got the exhaust and Im going to be using a turboII intake, just need a standalone. Im still undecided on rather I should use it in a first gen because of the weight. But hopefully with a little help from my friend, I would be very happy if i can break the 200rwhp mark. Also curious if anyone else is getting started on this challenge and what setup are you going with?
06-03-08, 05:00 PM
#167
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well, my project wont be done for another year, but the basics im plannin are
its on a 86 GXL
s5 rotors
s5 UIM w/ VDI rpm activation
RB header/presilencer
Apexi GT catback
SP and rebuild by banzai
alum flywheel
throttle body mod
ported LIM
corksport intake w/ headlight duct (hopefully drop intake temp a lil bit)
dyno tune w/ RTEK2.0
those are the biggest things. and if i still dont break at least 190 with that, Ima spend all next year researching ITB's, lol
its on a 86 GXL
s5 rotors
s5 UIM w/ VDI rpm activation
RB header/presilencer
Apexi GT catback
SP and rebuild by banzai
alum flywheel
throttle body mod
ported LIM
corksport intake w/ headlight duct (hopefully drop intake temp a lil bit)
dyno tune w/ RTEK2.0
those are the biggest things. and if i still dont break at least 190 with that, Ima spend all next year researching ITB's, lol
06-03-08, 10:03 PM
#170
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But back on topic, Im about to get my motor ported by jim from jpr. got the exhaust and Im going to be using a turboII intake, just need a standalone. Im still undecided on rather I should use it in a first gen because of the weight. But hopefully with a little help from my friend, I would be very happy if i can break the 200rwhp mark. Also curious if anyone else is getting started on this challenge and what setup are you going with?
06-04-08, 09:48 AM
#172
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That's true, but he said he's going with a standalone and TII manifold which (I think) will make it a lot easier to get there.
It's probably been posted before, but do you know how much power you're making with your setup?
It's probably been posted before, but do you know how much power you're making with your setup?
06-04-08, 11:28 AM
#173
Old [Sch|F]ool
The TII intake will probably flow worse after you modify it to mate up to the 6-port housings. It's really cramped right there and making the short and long sides even more disparate will suck. I'd only use that manifold with Turbo housings.
IMO, the best thing would be to take 6 port lowers and modify them to work with 4 port housings. That'd be a bit o' work, though...
IMO, the best thing would be to take 6 port lowers and modify them to work with 4 port housings. That'd be a bit o' work, though...
06-05-08, 08:52 AM
#174
Why would the turbo manifold be a "superior" design to begin with, if anything i would believe the NA one would be. I could be wrong, but I'm saying that because with a turbo the air isn't just sucked in the engine on its own, its pushed in there with the turbo, so travel of path doesn't have to be designed as good as the NA. But like i said i could be wrong.
06-05-08, 10:21 AM
#175
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I just assumed that since turboed engines have more air going through them, the manifolds would flow better to go along with it. I guess it made sense to me that you would want it to have higher flow, but when you put it like that it's understandable that the NA would be better.