Big Bore Throttle Body
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Big Bore Throttle Body
i was thinking about the throttle
body upgrade but i was also interestead
in the crank shaft pulley. my question is
that i know the throttle body improves throttle response and acceleration, but would it be even grater with the pulley.
body upgrade but i was also interestead
in the crank shaft pulley. my question is
that i know the throttle body improves throttle response and acceleration, but would it be even grater with the pulley.
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From: Rancho Palos Verdes, CA
Vehicle: 2008 Toyota Prius 2006 Suzuki SV650S
The pulley on the TB just changes the ratio in pedal travel to TB travel giving SLIGHTLY better throttle response.
The unorthodox crank pulley is lighter than the stock pulley, and is smaller. It drives your accessory belts at a slower rpm. This "frees" up hp. It is only good for maybe 3-5 hp, and has some possible bad side effects.
The unorthodox crank pulley is lighter than the stock pulley, and is smaller. It drives your accessory belts at a slower rpm. This "frees" up hp. It is only good for maybe 3-5 hp, and has some possible bad side effects.
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rolleyes.gif
My bad. I didn't read the original question correctly. I thought E151 was referring to the throttle body pulley, not the crank shaft (underdrive?) pulley.
D'oh.
Anyway, I'd still go with the throttle body over the pulley, because of the whole possible issue with harmonic resonance dampening. However, with the throttle body, you'll need to have your intake manifold bored out to truly benefit from the increase in air going through the throttle.
My bad. I didn't read the original question correctly. I thought E151 was referring to the throttle body pulley, not the crank shaft (underdrive?) pulley.
D'oh.
Anyway, I'd still go with the throttle body over the pulley, because of the whole possible issue with harmonic resonance dampening. However, with the throttle body, you'll need to have your intake manifold bored out to truly benefit from the increase in air going through the throttle.
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Vehicle: Mitsubishi Lancer Ralliart GSR
I got an 'Onpol special' TB - which is an enlarged stock.
I don't know about horsepowers gains, but the whole feel of the car was much better. Improved response and smoother acceleration. The car kinda feels like it doesn't have to try so hard.
I don't know about horsepowers gains, but the whole feel of the car was much better. Improved response and smoother acceleration. The car kinda feels like it doesn't have to try so hard.
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A Quick Intake Upgrade Overview
An upgrade to your stock intake feed, either via sticking a cone filter onto the end of your MAFS, or by installing a cold-air intake system will give a noticeable improvement in performance. How much improvement depends on how extensive the modification. Just a cone filter in the engine bay won't have nearly as much gain as a Random Special CAI. By doing this modification, you will have removed one of the first major bottlenecks of the stock intake: the convoluted stock intake feed and the cheap-o flat panel air filter. The next major intake bottleneck lies at the 55mm mouth of the stock throttle body.
A "Barney" SR throttle body or an Onpol-edition throttle body on it's own will give you some gains, but odds are, on it's own, you will be underwhelmed with the increase versus the cost. The end result will possibly be better if you also have an improved air intake feed. All in all, you have only moved the 55mm bottleneck back about four inches, from the mouth of the throttle body to the mouth of the intake manifold. rolleyes.gif
An enhanced throttle body with a bored and polished intake manifold (Onpol-edition) will give you much more noticable gains, most likely enough to where you will feel much better about the cost of the upgrades!
Air will be able to flow with less restriction all the way from the filter to the cylinder, and now the next major bottleneck is on the other side of the block, in the headers. There are minor tweaks you can do to the intake side, like finding places to straighten out the intake feed, but these probably won't show any more noticeable gains.
[ September 26, 2001: Message edited by: Iago ]
An upgrade to your stock intake feed, either via sticking a cone filter onto the end of your MAFS, or by installing a cold-air intake system will give a noticeable improvement in performance. How much improvement depends on how extensive the modification. Just a cone filter in the engine bay won't have nearly as much gain as a Random Special CAI. By doing this modification, you will have removed one of the first major bottlenecks of the stock intake: the convoluted stock intake feed and the cheap-o flat panel air filter. The next major intake bottleneck lies at the 55mm mouth of the stock throttle body.
A "Barney" SR throttle body or an Onpol-edition throttle body on it's own will give you some gains, but odds are, on it's own, you will be underwhelmed with the increase versus the cost. The end result will possibly be better if you also have an improved air intake feed. All in all, you have only moved the 55mm bottleneck back about four inches, from the mouth of the throttle body to the mouth of the intake manifold. rolleyes.gif
An enhanced throttle body with a bored and polished intake manifold (Onpol-edition) will give you much more noticable gains, most likely enough to where you will feel much better about the cost of the upgrades!
Air will be able to flow with less restriction all the way from the filter to the cylinder, and now the next major bottleneck is on the other side of the block, in the headers. There are minor tweaks you can do to the intake side, like finding places to straighten out the intake feed, but these probably won't show any more noticeable gains.[ September 26, 2001: Message edited by: Iago ]