I was wanting to know what differences to expect before I start playing with some spare parts. First off I have a stock JDM B16A with a JDM ITR intake arm, spoon filter, '98 spec oem JDM ITR exhaust manifold, 2.5" mid pipe to a Gen. one Mugen muffler. I have an extra '98 JDM ITR intake manifold & 67mm. throttle body, & Hondata intake gasket laying around. I was wanting to know what to expect as far as gains & losses & where they fall in the power band. Again, I'm not looking for suggestions on other set ups or other parts that would make more power. I already have these parts & it's not a matter of "don't waste your money, get this instead". I just want to know what to expect if I do decide to try these parts, only want to save my time & effort if it's not worth it. Thanks in advance for all who may take the time to help with this issue.

 

You'll find that the stock b16a intake/throttle body will kill the Type R intake/throttle body, performance wise, through 90%+ of the power curve. All the rest of your parts should work well on the b16a.

 

Yeah, thanks. I'm pretty happy with my current set up. I'm in the process of building an extra ITR head, & was planning on using the ITR throttle body with an AEBS manifold. Had these extra parts & I've heard differing opinions, just wanted to check before wasting my time. Any more opinions/dyno charts/ #'s would be appreciated.

 

Any more thoughts.
I've heard that the p30 responds well to a larger throttle body. Wondering if it might be worth running the ITR throttle body only for the time being.

 

I'm pretty sure that the 99/00 b16a throttle body was the same size as the ITR. If you come accross a 70mm, try bolting it on (after you port match it) and see what happens and report back.

 

If so, that would be the first time I've heard of any B-series other than the ITR motors having a 62mm TB...early B16A's had 58mm and later ones had 60mm, AFAIK.

 

You are correct, the b16a is 60mm and the type R is 62mm.

 

Yeah, I installed a '98 JDM ITR tb on my JDM B16A SIR II intake manifold yesterday out of curiosity & I have to say that my butt dyno noticed a very nice gain in throttle response & pull between 2400 rpm & 4800 rpm. Pulled hard all the way through vtec engagement, especially with the LSD tranny. I'm still running a stock P30 ecu, so there wasn't any drop off due to the 8200 rpm rev limit. I also did a few measurements with vatious throttle bodies I had laying around. First, a '98 JDM ITR measured 67.48mm @ the inlet & 62.37mm after the butterfly. Second was the '93 JDM SIRII B16A tb. It measured 62.4mm @ the inlet & 60.72 after the butterfly. Last was an older USDM B16 tb. It measured 61.7mm @ the inlet & 58.69mm after the butterfly. I did clean all openings of debris & gunk before measuring btw.

 

In all honesty I doubt you would have felt any difference from a change that small. Check it on the dyno and I'll bet you'll see little if any difference between the two, power wise.

 

Yeah, not really a huge difference, but it was a bit better. Definitely didn't suffer any. It was a bit more responsive though.

 

A larger throttle body will typically reduce the responsiveness or make no difference if the step up was only 2mm.

 

Yeah, I'm no dyno, but It seems to respond well. Might just be subliminal?

 

It's called the placebo effect.