Throttle Body

CassieWinch3ster

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I was wondering what throttle body would be better for performance between an SR Performance 75mm and a BBK 70mm
 

ttocs

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putting a 75 mm throttle body onto a intake that is only 70mm means that there is a 2.5mm lip on either side of where the TB meets the intake which means no gains. If you wanted to get the most out of the 75mm you would need to port the intake or grind out that extra 2.5mm lip out. That does not mean the SR performance is the one to go with though as I have had TB's that caused problems with idling. If someone else says they have used it and it is good then go with that but right now between the two options you gave one is larger than you need
 

RAU03MACH

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welcome to forums
if remember correctly Accu-Fab makes them to

and remember send in those pics
 

ttocs

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pics of your car are nearly mandatory. Vids earn bonus points and get you one step closer to the "members only" jacket that we all want.
 

Wood's 5.0

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Members Only jacket?!?!?!?!?!? What is this you speak of?!?!?!? First I've heard of it! I put a member errr...THEE Member in Members Only back in the day! Can I pick my own color??? Or is this like snipe hunting for the FNGs???
 

tvsn95

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putting a 75 mm throttle body onto a intake that is only 70mm means that there is a 2.5mm lip on either side of where the TB meets the intake which means no gains. If you wanted to get the most out of the 75mm you would need to port the intake or grind out that extra 2.5mm lip out. That does not mean the SR performance is the one to go with though as I have had TB's that caused problems with idling. If someone else says they have used it and it is good then go with that but right now between the two options you gave one is larger than you need
TTocks is right,,, If you want more performance you need to ingest MORE air..assuming that the TB is the choke is childish. BUT a common mistake. The aftermarket SELLS a bunch of stuff that is WRONG.
on a stock motor the TB is the LEAST of your problems... the heads are the trick. TB create all kinds of idle and off idle problem. It's due to the TUNE ( thats a diff topic )
But you cant just buy and bolt on. they require work .( Heads)
The BS that is sold ( Cold Air Intakes , as an example ) COST you power. But they make great $$ for the seller..
 

Notthenow

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tvsn, I agree with you and toccs, curious though, why you say cold air upgrades lose power, as I have not heard that before.
 

joemomma

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tvsn, I agree with you and toccs, curious though, why you say cold air upgrades lose power, as I have not heard that before.
I believe the consensus is that they are prone to heat-soak, and in turn raise IAT.
 

Notthenow

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I have thought that to work properly as"cold air" supply they need to be insulated as they go right over an exhaust manifold or headers. I would think they flow better unless the accordion wall of the stock tube helps with turbulant air.
 

ttocs

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I thought cold air just meant that it gets the air from the fender, outside of the engine bay. But the anderson is ceramic coated.
 

Notthenow

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Good to know, still hard to resist the urge to insulate it, especially here in AZ.
 

tvsn95

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tvsn, I agree with you and toccs, curious though, why you say cold air upgrades lose power, as I have not heard that before.
Lets think about Cold air's
There are diff types. first if it also contains the mass air then it MUST be the same size and in the same type of dynamic location or the tune changes.
If its nothing but a pipe, chrome , plastic , coated , ect. . it can make no diff. But there can be exceptions.
for instance. If the size is just somehow perfect , and at WOT the speed of the air develops enough inertia, ( energy ) to create a ram affect PRIOR to the TB , then you might get an increase in total air flow and an increase in HP. You will need a dyno that can read such small amounts it.s going to be difficult.
So if the piping is small and you can increase the velocity with out hurting flow, then yes ( maybe ) . Yeah and heat soak will probably be minimized.
If you make it big and your positive that it's not a choke point then it most likely will add nothing.
Now back to the Mass sensor , if you have a bend in the pipe and you install the sensor on the out side radius you will read more air flow than you would if you installed it opposite , the inside of the radius, .
It has to do with the compressibility of the air.
If its. installed in a larger pipe , And nothing else changes . the tune will read less air and be LEAN. due to the loss of mass going across the heated element of the sensor. The opposite is true for a small pipe.
So , you can see that by simply rotating the sensor location or moving the sensor up or down stream near a bend in the pipe can ( and will ) change the tune .
Also the factory did a very good job of having a cold air setup. Your efforts should try to repeat their engineering.
 

Notthenow

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So based on that, at what point does a stock pipe impede flow?
 

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