Yoshi style velocity stack and stock Throttle body.

Hi there, I finally got myself some 929 injectors and a Honda/ Acura FPR thats is identical to the 5th gen one but 3 bar of pressure. I was going to taper bore my throttle to 42mm but i backed off (for now) due to cost. I don't now for you but it would cost me more than 1500$ of my Canadian dollars to bore it.

So here's my questions:

Can i get worthy improvement with stock TB and yoshi style stacks?

Do i keep the stack going down to the TB or do i trim it creating a lip?

Do i even keep the lower part of the twin stack or just the upper part/ bottom of the air box would be better?

Have you done the math (lenght, spacing, rouding to the bottom of the airbox if no lower stack)?

If i were to taper bore it i'd just copy Mohawk's homework which is well documented here but here we go.

Also, i still plan on doing the big airbox and ram air intake with it.

Anyway, thanks in advance!

I tested the double stack arrangement as a part of my variable velocity stacks project.

Link to my thread

My testing showed that the gaps of 1cm and 2cm produce less overall power than no gap (basically a single long stack) and 3cm gap (basically a single short stack, the upper stack doesn't interfere with the airflow).

Neat stuff! Did you test it with the big air box mod and ram air intake? I way very well end up keeping the airbox stock in the end. We'll see.

No, but I've tested the removal of the snorkel and open top airbox at full throttle in 3rd gear. Snorkel removal gave a miniscule improvement with a nice bump in intake noise. Open top made no difference compared to removed snorkel but the intake roar was extreme. Absolutely deafening in VTEC even with earplugs in. I went back to the unmolested, snorkel-less airbox top.

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