ITBs vs. TB & IM
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ITBs vs. TB & IM
All the most powerful all motor engines that we see either on http://www.importreview.com or on the board are all running ITBs. Yet on the other hand, the worlds fastest all motor car is not running ITBs.
Are ITBs better for track racing as opposed to drag racing? Or does Erick's car have more potential if he went with a well tuned ITB setup vs. his 70mm TB and (obviously) very modified P72 IM.
Are ITBs better for track racing as opposed to drag racing? Or does Erick's car have more potential if he went with a well tuned ITB setup vs. his 70mm TB and (obviously) very modified P72 IM.
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From: retired 2/13/10
Re: ITBs vs. TB & IM (teg92)
i dont have the exact answer but i think u could better spend the money elsewhere rather than on ITBs. do somethin really trick to hte motor for the 2k ur goin to spend on ITBs. the price is outrageous. i know some ppl will flame me but thats ok cause those will b the guys that jump the bandwagons.
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Re: ITBs vs. TB & IM (hondaatwsu)
i dont have the exact answer but i think u could better spend the money elsewhere rather than on ITBs. do somethin really trick to hte motor for the 2k ur goin to spend on ITBs. the price is outrageous. i know some ppl will flame me but thats ok cause those will b the guys that jump the bandwagons.
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Re: Re: (Spoon1)
When Erick's racing ran the 10.2 was he still using the GSR manifold, or did he switch to the JG-edelbrock piece? I hard norm aubry and a few other cars switched to the JG piece.
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Re: Re: (Spoon1)
you dont necessary need ITB ,there more for road racing then drag .
Ericks is able to acomplish 10.2 with his TB ,IMO i think thats more then enough for any street driven car and all motor drag car.
Ericks is able to acomplish 10.2 with his TB ,IMO i think thats more then enough for any street driven car and all motor drag car.
[Modified by teg92, 6:38 PM 12/16/2002]
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From: lakewood, ca, us
Re: Re: (teg92)
JG intake manifold with a 70mm TB outflowed my ITB's (TWM 50mm)
so this combination should produse same or better peak HP.
Downside of that is lack of throttle response due to the large volume of the IM.
This is why road recers prefer itb's over im/tb, they get good peak and great throttle response.
If i was putting a my motor together again i'd stick with IM/TB....ITB's are a hassle(tunning,drivability and gas milage...too many headaches)
If you can make same power with IM/TB then it's not worth it unless you plan to road race.
so this combination should produse same or better peak HP.
Downside of that is lack of throttle response due to the large volume of the IM.
This is why road recers prefer itb's over im/tb, they get good peak and great throttle response.
If i was putting a my motor together again i'd stick with IM/TB....ITB's are a hassle(tunning,drivability and gas milage...too many headaches)
If you can make same power with IM/TB then it's not worth it unless you plan to road race.
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Re: Re: (genius)
genius, did you dyno both with the TWM ITBs and your jg/70mm combo? I'd imagine the torque and power curves would be very different.
I am going to attempt to drive this thing daily, but then again everyone would think I am nuts because I have no problems driving my nonvtec motor with 404's... I'm now going to run 405a's on the street... I don't mind flat on its face till 3000rpm...
Anyway, I did purchase a set of CBR954RR ITBs I am planning on custom fitting to my head and would really like to see the challenge and see what the fuss is about, but if I can be assured with a JG manifold and 70mm TB I could make just as good power, well its gonna be a tough choice. Its basically gonna cost me the same thing to run this custom ITB setup as it would to get the JG & 70mm TB, so you've got to factor in the coolness factor, originality, and that slim possibility that I could just get this thing to work pretty damn well...
I am going to attempt to drive this thing daily, but then again everyone would think I am nuts because I have no problems driving my nonvtec motor with 404's... I'm now going to run 405a's on the street... I don't mind flat on its face till 3000rpm...
Anyway, I did purchase a set of CBR954RR ITBs I am planning on custom fitting to my head and would really like to see the challenge and see what the fuss is about, but if I can be assured with a JG manifold and 70mm TB I could make just as good power, well its gonna be a tough choice. Its basically gonna cost me the same thing to run this custom ITB setup as it would to get the JG & 70mm TB, so you've got to factor in the coolness factor, originality, and that slim possibility that I could just get this thing to work pretty damn well...
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From: lakewood, ca, us
Re: Re: (teg92)
never dynoed the two on the same motor.
how big are the cbr itb's?..if smaller then 50mm and you going for drag motor then forget it .
remember those itb's were feeding 1L motor and your motor is 1.8+ i assume
how big are the cbr itb's?..if smaller then 50mm and you going for drag motor then forget it .
remember those itb's were feeding 1L motor and your motor is 1.8+ i assume
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Re: Re: (genius)
Hmm hard to say that those ITBs aren't giving you much more "area under the curve"...
They CBR ITBs are 43mm... Its not a drag motor, more of a nice trophy motor I can enjoy building, researching, learning, running at the odd drag strip and really enjoy lapping, and also be able to drive it around town...
What do you think of this...
quoted from http://www.jenvey.co.uk
For the power I expect to make, 42mm is what these guys recommend +/- 10%...
[Modified by teg92, 10:57 PM 12/16/2002]
They CBR ITBs are 43mm... Its not a drag motor, more of a nice trophy motor I can enjoy building, researching, learning, running at the odd drag strip and really enjoy lapping, and also be able to drive it around town...
What do you think of this...
quoted from http://www.jenvey.co.uk
<u>What is the best throttle body diameter?</u>
Factors influencing size are; Power output, RPM, cylinder head design, cylinder capacity, position of the throttle body in the inlet tract and position of the injector.
Choice of bore size is a balanced compromise resulting from the following;
1) A larger bore leads to lower flow resistance, but obeying the laws of diminishing returns.
2) A smaller bore leads to better throttle control and response (never underestimate) and improved fuel mixing.
3) The system should be considered in total - from (at least) trumpet flange to cylinder and proportioned accordingly.
Basic references for BHP per cylinder, assuming ca 120mm from butterfly to valve head and a max of 9,000 rpm are;
Up to 30 - 30mm, up to 33 - 32mm, up to 39 - 35mm, up to 46 - 38mm, up to 51 - 40mm, up to 56 - 42mm , up to 65 - 45mm, up to 74 - 48mm, up to 80 - 50mm, up to 87 - 52mm, up to 93 - 54mm.
These power figures may be increased by up to 10% in a purpose - designed, well proportioned system. As butterfly to valve distance increases, butterfly size will need to increase in proportion to system taper and vice versa. Lower revving engines and those with injectors placed before the butterfly will generally accept a larger body.
Factors influencing size are; Power output, RPM, cylinder head design, cylinder capacity, position of the throttle body in the inlet tract and position of the injector.
Choice of bore size is a balanced compromise resulting from the following;
1) A larger bore leads to lower flow resistance, but obeying the laws of diminishing returns.
2) A smaller bore leads to better throttle control and response (never underestimate) and improved fuel mixing.
3) The system should be considered in total - from (at least) trumpet flange to cylinder and proportioned accordingly.
Basic references for BHP per cylinder, assuming ca 120mm from butterfly to valve head and a max of 9,000 rpm are;
Up to 30 - 30mm, up to 33 - 32mm, up to 39 - 35mm, up to 46 - 38mm, up to 51 - 40mm, up to 56 - 42mm , up to 65 - 45mm, up to 74 - 48mm, up to 80 - 50mm, up to 87 - 52mm, up to 93 - 54mm.
These power figures may be increased by up to 10% in a purpose - designed, well proportioned system. As butterfly to valve distance increases, butterfly size will need to increase in proportion to system taper and vice versa. Lower revving engines and those with injectors placed before the butterfly will generally accept a larger body.
[Modified by teg92, 10:57 PM 12/16/2002]
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Re: Re: (DragDc2)
When Erick's racing ran the 10.2 was he still using the GSR manifold, or did he switch to the JG-edelbrock piece? I hard norm aubry and a few other cars switched to the JG piece.
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Re: Re: (teg92)
Teg92,
Do you have any pictures of the 929RR ITBS? or have you come across any websites or forums regarding technical information on the fuel injected CBR's???
How are you going to go about injectors, i think i read something about the Fuel injected bikes have something like 4 different settings or positions not exactly sure but they are not the same as our injectors.
Do you have any pictures of the 929RR ITBS? or have you come across any websites or forums regarding technical information on the fuel injected CBR's???
How are you going to go about injectors, i think i read something about the Fuel injected bikes have something like 4 different settings or positions not exactly sure but they are not the same as our injectors.
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Re: Re: (DragDc2)
Here's a site with a bit of info on building your own ITBs. I'm basically trying to build the same setup for my motor, but after reading this thread... I might reconsider... If you're wondering.. I'm using a set of ITBs off of a JDM spec Toyota 20valve motor... Can't remember the engine code, but it's out of the corrolla and trueno..
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Re: Re: (DragDc2)
Do you have any pictures of the 929RR ITBS? or have you come across any websites or forums regarding technical information on the fuel injected CBR's???
How are you going to go about injectors, i think i read something about the Fuel injected bikes have something like 4 different settings or positions not exactly sure but they are not the same as our injectors.
How are you going to go about injectors, i think i read something about the Fuel injected bikes have something like 4 different settings or positions not exactly sure but they are not the same as our injectors.
I found this last night...http://www.abdgraphics.com/iansite/ianthrottlebody2.htm. They are for a *cough* Neon *cough*, but it is the same principle.
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Re: Re: (KS-R)
Here's a site with a bit of info on building your own ITBs. I'm basically trying to build the same setup for my motor, but after reading this thread... I might reconsider... If you're wondering.. I'm using a set of ITBs off of a JDM spec Toyota 20valve motor... Can't remember the engine code, but it's out of the corrolla and trueno..
Disregarding the typical "unstreetable" characteristics of ITBs, wouldn't ITBs provide much superior throttle response and torque/power curves vs. TB/IM?
[Modified by teg92, 1:18 PM 12/17/2002]
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Re: Re: (Jeff C)
Here's a site with a bit of info on building your own ITBs.
Where? Did you forget to post it?
Where? Did you forget to post it?
Here you go;
http://www.abdgraphics.com/iansite/ianthrottlebody2.htm
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Re: Re: (Jeff C)
EDIT: I posted my reply to this in my other thread concerning the dynamics of ITBs more... We should allow this thread to discuss the benefits of ITBs vs a traditional setup. 
[Modified by teg92, 3:44 PM 12/17/2002]
[Modified by teg92, 3:44 PM 12/17/2002]
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Re: Re: (79 civic)
WHAT? $260? That's cheap, but what kind of manifold? Is he making it from scratch? How is he going to make it to incorporate all the sensors.. Seems like the runners are going to be too long if he has to include all the sensors..
Besides... I don't think all ITBs are the same.. so.. how is he going to build a set to accomodate for all the different brands of ITBs?
Besides... I don't think all ITBs are the same.. so.. how is he going to build a set to accomodate for all the different brands of ITBs?
