2 Throttle Bodies

[barryogen]

I was just reading a honda forum(I know, and I'll never do it again), and there was a guy with two throttle bodies as opposed to the traditional 1, or 1 per cylinder...

so what would it give you?
a bit better throttle response? (assuming it was closer to the cylinders)
a few more tuning headaches? (it seems to be harder to tune with multiple TBs from reading)

Is it common, I've just never seen it done.

[Mr Revhead]

in an application where you want to flow a lot of air, 2 TBs will help.
cant say iv seen it on many 4cyls, but is common on V8s.

[barryogen]

in an effort to answer my own question, I've been reading...

it appears to make the car more usable on the street too, as having a massive single TB on a car can make it tricky to drive, with smaller singles being easier.

Although I've also read that having a bigger single makes the torque rise more linear in fashion, and also more drivable on the street...

yay internet for consistency.

[frost]

i'd assume it has the same effects as having twin carbs on a 4k or 3t,

[xsspeed]

^^^^^^ just what i was gunna suggest, perhaps a more consistent air flow to each cylinder. Assuming they operate on two cylenders each not both serving all four, if you can get your head around that

[frost]

the problem with having a big throttle body is at slow speeds its quite jerky. even a slight touch of the pedal will allow a lot of air to enter the engine,
because of the size of a big single TB trying to restrict air flow is like a on/off switch,
my old motor i had a 70mm butterfly plate and it was a bicth to park, you sound like a complete fark revving the tits of it while parallel parking,

two medium sized TB will still flow as much as a big single but the control is much better,

[Dragger_Dan]

Huh, is that so now is it?
Well I've got four. HA!

[no_8wire]

this thread may be interesting

http://forums.toyspeed.org.nz/viewtopic.php?t=39203&highlight=throttle+bodies

[barryogen]

interesting that I seem to have forgotten stuff that I posted back then...

stupid age making me forget something something mumble mumble.

[mr_monkey]

You can avoid the over sensitive large throttle issue very simply.

the Nissan Q45 throttle uses a system of levers and wheels BUT you can achieve an identical result by using a custom throttle wheel with an offset center (so that it works like a cam lobe).

The idea is that butterfly movement becomes increasingly large (in relation to pedal movement) as you get closer to full throttle. EG, at low throttle settings the butterfly moves real slow and at full throttle the butterfly is twitchy and moves fast.

Hard to explain.

[Toymad]

You can avoid the over sensitive large throttle issue very simply.

the Nissan Q45 throttle uses a system of levers and wheels BUT you can achieve an identical result by using a custom throttle wheel with an offset center (so that it works like a cam lobe).

The idea is that butterfly movement becomes increasingly large (in relation to pedal movement) as you get closer to full throttle. EG, at low throttle settings the butterfly moves real slow and at full throttle the butterfly is twitchy and moves fast.

Hard to explain.

The 1UZ throttle bodies use the same method of cams on the butterfly shaft for better throttle control too.

[ee904age]

You can avoid the over sensitive large throttle issue very simply.

the Nissan Q45 throttle uses a system of levers and wheels BUT you can achieve an identical result by using a custom throttle wheel with an offset center (so that it works like a cam lobe).

The idea is that butterfly movement becomes increasingly large (in relation to pedal movement) as you get closer to full throttle. EG, at low throttle settings the butterfly moves real slow and at full throttle the butterfly is twitchy and moves fast.

Hard to explain.

The 1UZ throttle bodies use the same method of cams on the butterfly shaft for better throttle control too.

From memory, my 3S-GE (ST171) has a similar setup