Throttle bodies

Since i no longer need the boost return function of the standard G60 throttle body [currently used for the dump valve] is there an alternative i could use thats straight through and larger to flow better.

Boooo.... that's boring! I thought this was an interesting thread about proper throttle bodies, as in 1 per cylinder

I thought you were going for a 1.8T conversion? I need to read your project thread I think!

im just about to adapt a ABF tb to have a boost return linkage. The ABF 1 bolts to a audi tt or 225bhp 20v manifold but i guess you need 1 to fit an 8v manifold?
Make an adaptor up to go for a vr6 tb or summink

kevhaywire wrote:Boooo.... that's boring! I thought this was an interesting thread about proper throttle bodies, as in 1 per cylinder

I thought you were going for a 1.8T conversion? I need to read your project thread I think!

Sorry buddy, i am hoping to go 1.8T and as you mention 1 per cylinder that is what i was going to try and do on the 1.8T so its in the big bag of questions i have next to me, it just was not its lucky day.

Flusted wrote:im just about to adapt a ABF tb to have a boost return linkage. The ABF 1 bolts to a audi tt or 225bhp 20v manifold but i guess you need 1 to fit an 8v manifold?
Make an adaptor up to go for a vr6 tb or summink

Yes i would need it to the 8v manifold.

But is there any advantage to doing this as the next restrictions are the inlet manifold and valves etc.

prob give better throttle response, but i doubt much more power

Thats all my aim is tbh.

[You must be registered and logged in to see this image.]

ABF on left approx 65mm butterfly

Apparently Audi 2.2 5cyl throttle body will do what i want getting rid of the boost return and will bolt straight on.

Anybody know?

thats no different to a mk2 golf gti 1. or a golf 16v 1, or a corrado 16v 1

The audi 1 is an upgrade for mk1 gtis as they have smaller butterfly tb

Thats what i thought, but does it have a larger butterfly due to having no boost return.

nope. they are all the same inc g60

I had 1 years ago that i had machined out by 3.5mm and a 3.5mm larger butterfly fitted by alpina (that was his username)

Brill back to the drawing board then.

get a g60 inlet mani, cut the tb flange off and get something more exotic welded on?

What more exotic, TB or mani.

TB, the yanks use 3" mustang jobby

Bigger throttle body = good top end power
smaller throttle body = improved throttle response.

65mm throttle body is good for 550hp-600hp so God knows why they go to 75mm on most applications.

JNLRacing wrote:Bigger throttle body = good top end power
smaller throttle body = improved throttle response.

65mm throttle body is good for 550hp-600hp so God knows why they go to 75mm on most applications.

and what do you stand to loose by junking the g60 one.
isn't that throttle body designed to give the best of both worlds?

JNLRacing wrote:Bigger throttle body = good top end power
smaller throttle body = improved throttle response.

I suppose that is one of the advantages of direct to head throttle bodies, you get excellent throttle response without compromising the top end power.

Could you not use something like a Range Rover V8 throttle body? Most probably bigger than a VR one but not like those huge Mustang jobbies.

dirtytorque wrote:

and what do you stand to loose by junking the g60 one.
isn't that throttle body designed to give the best of both worlds?

Potentially loose a bit of throttle response by going to single tb but gain a little more top end due to less turbulance through the single butterfly. It's also easier to get a true representation for mapping using a tps sensor. Although on the automatic passat g60's they did manage to run a tps instead of microswitches.

My mrs's 8v 2l mk3 was super responsive with the single butterfly, years ago i modded a 16v inlet to run a porsch 944 single and that was also made very responsive?

Flusted wrote:My mrs's 8v 2l mk3 was super responsive with the single butterfly, years ago i modded a 16v inlet to run a porsch 944 single and that was also made very responsive?

I have a 8v single butterfly throttle I was going to use on my 16vT

Yeah, the 16v 1 is a bit bigger, i have both here

^^^^ I stress potentially, unfortunatelly there is no hard and fast rule over single vs double as it depends on the engine's requirement for air and the size of the butterflies involved.

The main key is the bigger the throttle body the less throttle response and the more top end power.

And big throttles can be a pig to map smoothly. The slightest opening of the throttle can have a massive increase in air flow, compared to a stock throttle, which is designed to be smooth and progressive.

Where boost is concerned, throttle size isn't important imo. People get 700hp from VRTs with bone stock OBD2 throttles, which has the smallest throat and butterfly of all the VR6 variants.....and being the smallest, it's more responsive off boost too.