Best aftermarket throttle body.

[4gsx63]

why not just go with a stock 1g n/t throttle body. i beleive it is 65mm all the way through. and you wont have to replace your throttle body gaskets everytime you take the throttle body elbow off sense you can use a coupler there. i am planning on doing this and blocking off the lower half of the throttle body. if you have 2.5" intercooler tubing, then 65mm is perfect for the transition into the intake manifold. while the stock 60mm is a bit smaller then 2.5" intercooling tubing.
just throwing out another option for you.
later

I'm getting ready to install a n/t TB with JM SMIM and 3" UICP. I will be using 3.0"-2.75" reduce coupler. How do you control the idle if you block off the lower half of the TB?

 

[Car Cannibal]

I had Steve max port the stocker, it came out to 66.5mm and with the half shaft mod almost 70mm of flow.

Too many DSM guys had theoretical issues with the max port so Steve will only do it if the customer asks for it. I have known Steve for a while so I am not worried about it as he was confident it would be fine. It's been great and holding 26psi daily without any issues.

 

[insanewayne]

Thanks for the info guys, I'll think Ill give the accufab a try.

 

[insanewayne]

Sorry to ressurect my own post, but things got delayed, and I'll be buying the manifold in the next few weeks. After some more research I'm thinkin the Q45 is the way to go....

The only thing I dont like, is how its 90mm, then tapers down to 80mm.....so I'm going to have 3" piping, open up to 3.54" then back down to 3.15", then into a massive plenum...

I'd much rather not have the fluctuation in diamter screwing with my air velocity.

Is Hal out there? Or someone who has one who could tell me how hard it would be to open the whole thing up to 90mm? Then adjust the biss to compensate for the extra air getting around the flapper at idle?

Or am I just dreaming here...

I'd also have no problem making 90mm smaller, so that it went from 3", to maybe 3.10" then the final 3.15" at the flapper.

Someone stop me if I'm getting to carried away over shit thats not going to matter when I'm ramming in air at 30+ psi. ....although I think it would, specially for the rest of the air flow range as well.

 

[pneumo]

Here's the inside scoop on the Q45 diameters. It's called a 90mm TB because the OD of where the intake pipe clamps onto the TB measures 90mm. Just like when you measure a 3" intercooler pipe, it's 3" OD. The ID of a 3" aluminum IC pipe is 72.5mm. A 3" steel IC pipe will have a 74mm ID. The ID of the Q45 TB starts at 83.5mm, then gradually tapers to 80mm at the plate, then opens up again to 82mm before the manifold. The diameters really don't change that much. It's already slightly bigger than a 3" IC pipe.

I verified these measurements on my spare Q45TB.

It would be tough to open it up more since you'd have to make a larger plate. Otherwise it would idle at 6k rpm all the time. There is no BISS, just a set screw to adjust idle speed, and the set screw simply holds the plate open slightly.

 

[insanewayne]

Ok, thanks a bunch for the info pneumo. I wish there was a way to plumb the 3" pipe right to the 80mm part, and skip the expension....but I think I'm gettin a lil carried away with what's going to matter.

 

[pneumo]

Don't forget, the 80mm plate has a 12mm thick shaft holding it in place. Even when the throttle is open the shaft blocks part of the opening, so it has the flow area of a 72mm ID pipe. How's that 3" IC pipe looking now?

 

[insanewayne]

Yeh, that's why in my last post I said I think I'm getting a little carried away with it all...I realized that the turbulence and obstructions caused by the plate and shaft are going to outweigh my concerns about the 3.5mm in size expansion.

 

[Slippi84]

Sorry to bring this thread back but are there any running issues to installing one of these and eliminating the idlse switch or ips on a 2g. I would love to mount this up to my 420a Venom manifold(yes I know NA is diffrent ) but I don't want to have the car not idle or what not. I can live with high idle or what not but nothing to crazy.