Throttle body and body base.

[Sovereign]

I've had a nagging idea in my head the last few days. I've seen the occasional thread come up asking about boring throttle bodies, and the answer has always been the same: a dead end once the throttle body base was taken into account.

The base holds two important devices: the Idle Air Control Valve, and the Starting Air Valve. Both are mounted on the side of the base, the base itself being a (roughly) 90 degree angled tube connecting the throttle body to the lower plenum.

By my reasoning, it shouldn't be hard at all to make a flange for the lower plenum. It would hardly be a problem to make a flange for any sort of aftermarket throttle body readily available on the market. Also, it wouldn't be out of the scope of possibility to make a flange for the IACV and SAV. That merely leaves the tube itself, and incorporating all three flanges to fit to it.

I've drafted a few ideas, and might even be able to make "flanges" out of the OEM throttle body base. The lower plenum has a tricky shape, but it shouldn't be too hard to work with. It wouldn't be hard at all to cut one up and retain the pieces and shapes I'd need.

The only thing left to mix into the idea, is the size itself. I know we have a few mathematicians, engineers, and people with senior experience around here. What would you all say the ideal diameter to aim for would be? 3.2 - 3.5 liters moves a bit of air, but not nearly as much as a V8. Typical aftermarket throttle body bases I see available (350 V8 motors) run minimum of 90mm, so I figure that's definitely the point of "too big".

The idea I'm looking to achieve is to make a piece that will adapt an off-the-shelf aftermarket throttle body to the OEM manifold. Suggestions and feedback welcome.

[Quaraxkad]

Put the biggest throttlebody on there you want, it's not going to make a difference... The air still has to be pulled through these tiny little ports.

[Sovereign]

So you're saying that spot is more constricting than the throttle body and base? Can it not be bored out?

[rwheadon]

Originally Posted by Sovereign

So you're saying that spot is more constricting than the throttle body and base? Can it not be bored out?

Since the intake system is already tuned you are going to keep hitting bottlenecks. By continuing through the path you will end up starving at the valves too right?

15 years ago there might be enough interest for you to pursue designing a performance intake and some valvetrain mods, but at this point it's going to end up being academic at best I think.

I remember that people have bored the TB, intake manifold and runners to open up a path to heads and removed the VIS but I don't know that any appreciable HP gains were ever disclosed.

If it suits you keep pushing through for your own satisfaction. Innovation might be too late for large adoption, but who knows.

rich

[Sovereign]

Well, I'll start with the simple stuff. I'll get a throttle and base made up, and run it through the local dyno. I'll even do two setups over a stock run. I'll get numbers for throttle and base alone, then some numbers for the same parts in a manifold that's had some work done to it. It'll be a fun little side project.

[013Reaper]

I've ran into similar questions....


It's this interest that has me wondering would we see any gains going with an ITB set up over the normal intake configuration again...with so many sensors in the Throttle body I did away with the notion but I don't see why they couldn't be bypassed and done..

[rwheadon]

Originally Posted by Sovereign

Well, I'll start with the simple stuff. I'll get a throttle and base made up, and run it through the local dyno. I'll even do two setups over a stock run. I'll get numbers for throttle and base alone, then some numbers for the same parts in a manifold that's had some work done to it. It'll be a fun little side project.

Several of us had a custom throttle body base offered by a member here. I sold mine before using it but it basically insulated the throttle body from intake temp and gave a little more "volume" but don't know if it's dyno tested.

It makes a really cool whine when revving though, so that's worth at least 5hp.

rich

[The-Teej]

Originally Posted by rwheadon

Several of us had a custom throttle body base offered by a member here. I sold mine before using it but it basically insulated the throttle body from intake temp and gave a little more "volume" but don't know if it's dyno tested.

It makes a really cool whine when revving though, so that's worth at least 5hp.

rich

Where would I find one of these? Like to check out the sound!!

[Chrispy]

Or you can just contact maxbore http://maxbore.com/ for a larger throttle body.

If you remove the sensors you can have the throttle neck extruded. Had mine done. It smooths the passages out real nice. Air speed/velocity is more important than increasing the volume of the throttle neck

[The-Teej]

Originally Posted by Chrispy

Or you can just contact maxbore http://maxbore.com/ for a larger throttle body.

If you remove the sensors you can have the throttle neck extruded. Had mine done. It smooths the passages out real nice. Air speed/velocity is more important than increasing the volume of the throttle neck

well aren't you just a gold mine today