best size throtle body for B18C7

**big tone** · 18-09-2007 02:44 PM

i see alot of ppl saying go the biggest tb you can get (more air flow) then i see alot of ppl also saying not to go big caus its no good( too doughy down low)
my application will mainly be for street and drag

SO, what size throttle body would be best for
B18C7
with stage 2 crower cams
cam gears
4-2-1 x-force headers
2 1/2" exhaust
s300 hondata

**fatboyz39** · 18-09-2007 04:29 PM

Either 65mm or 68mm.

65mm won't require the intake manifold to be bored out.

Ill go for 65mm thorttle body.

What intake system you running?

**big tone** · 18-09-2007 08:39 PM

Originally Posted by fatboyz39

Either 65mm or 68mm.

65mm won't require the intake manifold to be bored out.

Ill go for 65mm thorttle body.

What intake system you running?

itr, thats it. still susing out that as well weather to leave it or get something else that wil work better.

**big tone** · 19-09-2007 06:56 PM

Originally Posted by fatboyz39

Either 65mm or 68mm.

65mm won't require the intake manifold to be bored out.

Ill go for 65mm thorttle body.

What intake system you running?

why do you recomend 65mm tb and not 68mm

whats the difference other than the im being bored out.
is a 70mm too big

**Waggy** · 19-09-2007 09:00 PM

I've been recently told that a 70mm is a good way to go. Just make sure the IM is port matched.

**big tone** · 19-09-2007 10:58 PM

Originally Posted by Waggy

I've been recently told that a 70mm is a good way to go. Just make sure the IM is port matched.

I need reason's on why it is better as we are both after the same thing
i want mid to top end power (torque) the theory behind the sizes would be good.

**SPEEDCORE** · 20-09-2007 01:51 PM

The theory behind sizes is flow vs air speed.

People are also mentioning sizes.... are you measuring at the plate?

**Professional** · 21-09-2007 02:26 AM

B18C7 is Type R engine. I think 70mm is the biggest size for Type R IM. Also, you got Cams, Exhuast and ECU. For the TB, i think 70mm is the best or you got some spare money, get a Quad throttle (You will surprise). If you want to get more Quad throttle's info, you may ask "barefootbonzai" in this forum. He got Quad throttle in his B18CR before. Just my opinion.

**Professional** · 21-09-2007 02:27 AM

Just found the link:
http://www.ozhonda.com/forum/showthread.php?t=55347

**fatboyz39** · 21-09-2007 12:20 PM

Biggest Bore size you mean by 70mm?

Ditch those headers and get some better ones. e.g buddy clubs, toda and etc.

As for cams? how big are they compare to other cams? i.e ITR ones

**SPEEDCORE** · 21-09-2007 12:27 PM

http://www.crower.com/cat/import/hon...s/b_vtec.shtml

**big tone** · 21-09-2007 04:53 PM

Originally Posted by fatboyz39

Biggest Bore size you mean by 70mm?

Ditch those headers and get some better ones. e.g buddy clubs, toda and etc.

As for cams? how big are they compare to other cams? i.e ITR ones

but where will i get gains with 70mm bottom, middle, top or all round gains as compare to a 65mm tb