Independent Throttle Bodies
03-31-2004, 01:00 PM
#111
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Join Date: Sep 2002
Location: Savannah, Ga
Posts: 2,763
Originally Posted by White_FC' date='Mar 31 2004, 08:53 AM
I agree... download the movies of the 300HP brideport on the dyno... Horn.. pure horn.. that's all I have to say 
300hp@10Krpm.. pretty decent effort in anyones books.
In fact there is a new IPRA race car up here with a rohan ambrose built 13b brideport in it, (allegedly 300hp jobbie) and all I have to say is WOW, it hauls, i'm not certain how much this particular engine puts down that i'm talking about, but wow, it really does have some speed to it.
But yes, I feel everyone here in this thread should have a read of that thread to have a better understanding of some tried and tested inlet ideas before posting more stuff in this thread again.. Great read, that is all
(ps, yes i realise there were way to many 'threads' in that last sentance... )
300hp@10Krpm.. pretty decent effort in anyones books.
In fact there is a new IPRA race car up here with a rohan ambrose built 13b brideport in it, (allegedly 300hp jobbie) and all I have to say is WOW, it hauls, i'm not certain how much this particular engine puts down that i'm talking about, but wow, it really does have some speed to it.
But yes, I feel everyone here in this thread should have a read of that thread to have a better understanding of some tried and tested inlet ideas before posting more stuff in this thread again.. Great read, that is all
(ps, yes i realise there were way to many 'threads' in that last sentance...
I think I just got a design for the intake manifold for my SP...
03-31-2004, 03:27 PM
#112
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Join Date: Jan 2002
Location: CT
Posts: 1,345
Originally Posted by mazdaspeed7' date='Mar 30 2004, 10:09 PM
Yeah. Its called slide throttles. (original name, huh?) Some of the guys runnign all motor rotaries are using them on their PP engines. At WOT, there is nothing blocking the intake tract like with a typical throttle. But its very much a race part, they arent as good at low throttle. Sealing problems result in whats basically a permanent vacuum leak.
03-31-2004, 03:39 PM
#113
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Join Date: Jan 2002
Location: CT
Posts: 1,345
i have done a bridge on just the aux port on a s4 engine, that engine was good for what it was, i raced it against my car alittle while ago, and was not any faster then my streetported s5 car. i also driven that same aux bridge car, and its nothing special like MS7 says its not worth it and the intake manifolds are not setup for it.
this was more of a trial thing since at the time there were no known aux bridges running aroudn and it was a good idea at the time and even if it didnt make much power it was atlest worth a try.
if you dont belive him and others that tell you aux bridge on stock manifolds wont do jack you can go ahead and do that yourself. i dont have exact dyno numbers for you for same exact engien runing with and without aux bridge port but i can tell that if there is a diffrence its not even wroth spendding the time bridging that aux port.
if you want a fast NA car a good place to start woudl be of course to get a nice exahsut setup and then get a real engien managment not something that was put together after all the years of somkign pot in college and makign a system for what is now called an rx7. and get some ITB intake setup with shorter runners.
also here are some DYNO numbers on what i am talking about, not only it will cost you less but it will be much less pain in the *** and a proen method already. plus you dont even have to open up your engine to get this power.
everyone is so quick to open up teh engien and start portign without realizing what portign really does or if its even nesseccary in their quest for what they want out of the car.
here are the pics and text with it.
http://24.2.177.252/cars/Manuals-Diagrams-...%20Sport%20ITB/
this was more of a trial thing since at the time there were no known aux bridges running aroudn and it was a good idea at the time and even if it didnt make much power it was atlest worth a try.
if you dont belive him and others that tell you aux bridge on stock manifolds wont do jack you can go ahead and do that yourself. i dont have exact dyno numbers for you for same exact engien runing with and without aux bridge port but i can tell that if there is a diffrence its not even wroth spendding the time bridging that aux port.
if you want a fast NA car a good place to start woudl be of course to get a nice exahsut setup and then get a real engien managment not something that was put together after all the years of somkign pot in college and makign a system for what is now called an rx7. and get some ITB intake setup with shorter runners.
also here are some DYNO numbers on what i am talking about, not only it will cost you less but it will be much less pain in the *** and a proen method already. plus you dont even have to open up your engine to get this power.
everyone is so quick to open up teh engien and start portign without realizing what portign really does or if its even nesseccary in their quest for what they want out of the car.
here are the pics and text with it.
http://24.2.177.252/cars/Manuals-Diagrams-...%20Sport%20ITB/
03-31-2004, 04:31 PM
#114
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Join Date: Dec 2003
Posts: 162
Hrrrm.
I have studied that article very carefully, and calculated the torque curve to see what is actually causing the effecte seen. Turns out that the carb and EFI torque curves are IDENTICAL, but offset by 500RPM.
That engine was street ported, so your arguament about opening up the engine doesn't quite hold true.
Just for the record, here is my Mk1 inlet. Mk2 will be based on GSXR throttle bodies.
BTW: what does 'not something that was put together after all the years of somkign pot in college and makign a system for what is now called an rx7' mean in plain english?
I have studied that article very carefully, and calculated the torque curve to see what is actually causing the effecte seen. Turns out that the carb and EFI torque curves are IDENTICAL, but offset by 500RPM.
That engine was street ported, so your arguament about opening up the engine doesn't quite hold true.
Just for the record, here is my Mk1 inlet. Mk2 will be based on GSXR throttle bodies.
BTW: what does 'not something that was put together after all the years of somkign pot in college and makign a system for what is now called an rx7' mean in plain english?
03-31-2004, 04:50 PM
#115
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Join Date: Jan 2002
Location: CT
Posts: 1,345
Hrrrm.
"I have studied that article very carefully, and calculated the torque curve to see what is actually causing the effecte seen. Turns out that the carb and EFI torque curves are IDENTICAL, but offset by 500RPM."
this coudl eb due to anything, even a slightest cahnge in diameter or where the actual plates are on both manifolds. also slightly more power from the haltech could be due to the the fact taht u can tuen EFI better.
"That engine was street ported, so your arguament about opening up the engine doesn't quite hold true. "
sorry about that part, i did read teh article a while ago and thought it was on a stock port motor, i am goignt to reread it now.
"Just for the record, here is my Mk1 inlet. Mk2 will be based on GSXR throttle bodies."
i can barely see antyhing in that pic its too small, looks like some shiny itb?
BTW: what does 'not something that was put together after all the years of somkign pot in college and makign a system for what is now called an rx7' mean in plain english?
i hate the stock ecu and all the wiring and everythign with the whoel stock mazda efi system, it was done back in the early 80s when the magic pills were popular. basicly my paint was beign if you have anythgin more then an intake and exahsut on teh car you really need an EFI or carb setup that is appropriate.
"I have studied that article very carefully, and calculated the torque curve to see what is actually causing the effecte seen. Turns out that the carb and EFI torque curves are IDENTICAL, but offset by 500RPM."
this coudl eb due to anything, even a slightest cahnge in diameter or where the actual plates are on both manifolds. also slightly more power from the haltech could be due to the the fact taht u can tuen EFI better.
"That engine was street ported, so your arguament about opening up the engine doesn't quite hold true. "
sorry about that part, i did read teh article a while ago and thought it was on a stock port motor, i am goignt to reread it now.
"Just for the record, here is my Mk1 inlet. Mk2 will be based on GSXR throttle bodies."
i can barely see antyhing in that pic its too small, looks like some shiny itb?
BTW: what does 'not something that was put together after all the years of somkign pot in college and makign a system for what is now called an rx7' mean in plain english?
i hate the stock ecu and all the wiring and everythign with the whoel stock mazda efi system, it was done back in the early 80s when the magic pills were popular. basicly my paint was beign if you have anythgin more then an intake and exahsut on teh car you really need an EFI or carb setup that is appropriate.
03-31-2004, 05:11 PM
#117
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Join Date: Dec 2003
Posts: 162
Originally Posted by kahren' date='Mar 31 2004, 02:50 PM
this coudl eb due to anything, even a slightest cahnge in diameter or where the actual plates are on both manifolds. also slightly more power from the haltech could be due to the the fact taht u can tuen EFI better.
<snip>
i can barely see antyhing in that pic its too small, looks like some shiny itb?
<snip>
i can barely see antyhing in that pic its too small, looks like some shiny itb?
They are 50mm DCOE throttle bodies grafted onto a hurley SU manifold. Way off optimal but they fit nicely in the car and I get good cold air into them. They will be a good baseline to compare other things to.
03-31-2004, 10:14 PM
#119
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Join Date: Mar 2004
Location: Tacoma, WA
Posts: 179
Hi,
We manufacture cast manifolds on the shelf, most are DCO (Side Draft) for 12a 13B's.
We have had these independantly dyno'ed so if you would like a copy just call our office and they can fax you the comparision sheets. BTW we also manufacture cast manifolds for the 12a, 13b & 20b in Supercharged applications
We manufacture cast manifolds on the shelf, most are DCO (Side Draft) for 12a 13B's.
We have had these independantly dyno'ed so if you would like a copy just call our office and they can fax you the comparision sheets. BTW we also manufacture cast manifolds for the 12a, 13b & 20b in Supercharged applications
04-01-2004, 01:14 AM
#120
Senior Member
Join Date: Dec 2003
Posts: 162
Originally Posted by kahren' date='Mar 31 2004, 04:18 PM
that purple car is that what its in ?
Goes like a greased rat.