Initial Development And Prototyping Of A 102 mm GM LS Throttle Body On A Supercharged Tundra

Yes, that might work well!

Also, I suspect (this is maybe) many Aisin throttle bodies share the motor and electronics. They simply scale the throttle plate area and bolt pattern up or down to fit the application. Circled area could be the same, so supplies of motors and parts might be plentiful and thus easily/inexpensively sourced.

 

Great! Especially if it can be scaled up as @Jowett stated.

 

@snivilous If the big throttle bodies are simply too on/off, what about designing in a progressive radius ramp for 1/2 the throttle plate? The stock throttle body on my old VW Corrado has such a design. It may(?) add some restriction at full throttle, but maybe the drivability will be worth it? Run the numbers and compare what 1/2 the throttle plate open for say, 10 - 15 degrees of sweep will give vs a smaller bore w/o?

 

Funny you say that since I had been thinking of a similar concept, though I didn't know it had been incorporated into anything. I had a few random thoughts, such as two butterflies where one activates past a certain throttle, or having half the plate being flat and the other half being part of a hemisphere so only the top of the plate opens initially and eventually the bottom of the plate also open, etc.

Was also thinking if there's benefit to a modular design where the housing is the same but you can choke it down to like a 90mm, maybe have inserts and a different plate to drop the inner diameter down? Flip side of that concept is if it can drive fine being a big throttle body, then maybe there's no advantage to it being able to be reduced. My truck will be a good test article in that case since I have (and can convert to) a very stock supercharger setup. If I can get a 100mm to run fine on my truck then there's probably no reason to make smaller sizes.

In regards to the coolant passage I was thinking of leaving that out, though that could easily be incorporated with just a through hole and some nipples, though seems like if you're at this level you probably don't care much for that feature?

@Mdl where is your water meth injection setup? Would be interesting to add a port on the throttle body for water meth/nitrous. Or other things maybe of value? Extra ports never hurt anyone.

Oh another idea I had, along the lines of necking down, is the back side could be setup for an insert to taper the throttle body down to whatever the supercharger inlet size is to try and maintain good airflow.

 

Maybe make the coolant ports 1/8npt so people could use them or plug them, I love the idea of the modularity for sizing, and would also be interested in a post-TB port for injection...was also thinking maybe the motor could be flipped out the other way like my 90mm GM TB is, depending on clearance...mine fits but only because of your adapter.

 

Can you show a top down view so I can see where the motor sits relative to things?

 

I believe for SC'd AEM calls for it to be within 6 inches of the TB inlet for proper atomization i have mine about 4 inches. I know people have it post TB wth an 1/8 npt just after the blade or in the spacer plate.
Would be nice to have it for both W/M and Nos or?

 

It's got maybe 4mm between the TB and the vacuum hose on the bypass valve

 

Yea I’d rather have the motor facing towards the front at the rad more room there.

 

This is on the tvs1900 with the 103mm TB with my bastardized mounting. On the 2650 it seems Iike it would hit the SC body.
But wouldn't you be using the gm digital TB design motor like the Toyota as it wouldn't be extended out as much?
**referring GM 95mm has similar design to Toyota TB.

 

More owners have the mag/harrop 2650 and Whipple setups than the tvs1900.

 

The one I have won't mount 180 out because of the radiator overflow, but could make it work with a different angle.

 

That’s the idea, flopping the motor over 180 places it off to the side. The problem is the plastic cover contains the connector, sensors, and such.

Modular would be nice.

Here is how VW built the ramp…

 

Don't follow, Gm digital TB design motor?

I'll be using all the guts out of the stock Tundra throttle body. Call that whatever you want I should be able to mount the motor either under/over the TB or sticking out away from it.

 

I believe GM has it where they can be clocked 20deg left or right. So Toyota TB could be clocked left or right.

 

It looks like if the motor was flipped so it went towards the cab and sat where the coolant line is there'd be plenty of room?

 

@snivilous you may want to make my adapter orient a few ways so we can see which fits best when I add it on.

 

The largest intake is the Whipple at 103mm right? So I should probably have ~103mm be the baseline size since it's easy to choke it down. Unless there's opinions for a different size as the baseline?

 

Just referring to the different designs and how each one differs. Gm 95mm=Toyota 76mm and Rcf TB.

 

That's good. It can be adapted from the 103mm on down as I had it mounted on the 1900.

 

Only thing I can tell could be a problem is the vacuum line by the TB.

 

But not sure how low that motor would sit that’s on that TB

 

We'll see if I can push 103mm. It looks like 100mm is the EASY limit based on the Tundra bolt pattern. Might have to see if I can get sexy and push it a bit. @reywcms I forget, does the Whipple use an adapter in stock form since the Whipple bolt pattern isn't for a Tundra.

 

Whipples inlet is 102mm and yes in stock form they include an adapter with a nice bell flow. Let me snag a pic uno momento

 

Pics added

 

Someone double check this since it seems wrong, but this is what the CAD from the throttle body spacers I've done says:

Whipple: 99mm inlet
Harrop: 84mm inlet
Magnuson 1900/2650: 90mm inlet

 

Harrop Tundra inlet is 84mm

Here is the adapter that comes with the Harrop GM front snout, it fits snug into the snout and narrows the inlet from 102mm to 90mm...could probably do something similar.

 

Tvs1900 I was able to port out to 94mm with 76mm bolt pattern.

 

One issue I ran into when having the meth injection nozzle past the TB - if a tiny piece of dirt or whatever was preventing the meth solenoid from seating fully when off, the vacuum in the intake would a suck the whole bottle of water/meth very quickly
The first time it happened, I was at the track and was sure I blew the head gasket after a run, it was running like crap and blowing white smoke. Then it magically stopped after a while and I noticed the tank was empty, so I put two and two together. After it happened a couple more times afterwards, I relocated the nozzle to before the TB.

 

I should have added that when after TB you need a solenoid to prevent it being siphoned out.
Good catch!