changing to a bigger throttle body...is it worth it?

[itrekcivic]

Just looking at different options here. Correct me if im wrong but i just read the stock jdm itr throttle body is 65mm? What size is the stock inlet on the manifold? Wouldit be beneficial to have the im port matched to a bigger throttle body?

[Dave_B]

Just looking at different options here. Correct me if im wrong but i just read the stock jdm itr throttle body is 65mm? What size is the stock inlet on the manifold? Wouldit be beneficial to have the im port matched to a bigger throttle body?

I can't confirm, nor deny on the JDM throttle body, but I believe it's the same size at the USDM unit.

As for when you do go with a bigger TB, yes it is benificial to match the inlet on the intake manifold, as you don't want to negate that extra air from hitting a "wall" if you will.

Now all of this bigger TB/IM would take into consideration that you need this mod. The stock unit holds up pretty well for just simple bolt on affair. It's when you start porting the head, using higher lift camshafts and boosted applications is where you will see the benefits of a larger TB and IM combo.

[itrekcivic]

Well I just ordered my chipped p28 setup. That was the last thing I wanted to order before I upgrade my cams.Any help on that subject would be nice to. I'm looking at toda spc b or crower stage 2. I just can't seem to find anyone with experience with these on the r motor willing to share their experiences? So once I do the cams is when it would be beneficial to port match with a bigger tb?

[Dave_B]

Well I just ordered my chipped p28 setup. That was the last thing I wanted to order before I upgrade my cams.Any help on that subject would be nice to. I'm looking at toda spc b or crower stage 2. I just can't seem to find anyone with experience with these on the r motor willing to share their experiences? So once I do the cams is when it would be beneficial to port match with a bigger tb?

When you say chipped P28 setup... is a ROM already burned for you, or are you going to put the car on a dyno and have it properly tuned?

Also, what compression ratio are you running? What other valve train upgrades are you going to do?

If stock CR, and only a "B" or stage 2 street cam, I don't think a bigger TB or IM is going to benefit you much and that the money could be better spent elsewhere.

The only reason I had to do the IM and TB on my setup is that I run a ported head, big cams and when on a dyno you could see in the softwhere, where it was sucking vaccum. Basically, what that equates to is that I didn't have enough volume or flow of air behind the head. Now that this motor is going in my track car, and with an even less restrictive exhaust, I think it's in my best interest to go with the IM/TB combo.

[Aquafina]

Not going to do much other than hurt low end on a stock engine. Toda B's are good, I'd stay away from Crower, for some reason they just don't make the power other good cams do.

[citrus3000psi]

I can't confirm, nor deny on the JDM throttle body, but I believe it's the same size at the USDM unit.

I have a JDM TB and they are the same size.