G60 throttle body porting - new update

[JMC 0]

Cheers flusted. I ordered some today, so hopefully it will do the business.

[ninoG60 0]

any updates?

did it make any noticeable difference porting the elbow and knife edging the throttle body?

[JMC 0]

Strangely enough the porting is still going on. I had the elbow welded up so I could remove loads more material (I will get a photo when I have a few spare mins). In the end I decided not to knifeedge anything, just to smooth out any shoulders. I am planning on getting quite a bit of work done before too long and I hope this will be one of the bits which will be ready to go on by then. Will keep you informed.

[boost monkey 0]

So is porting this section like porting a manifold - a trade off between torque and horsepower?? Just been thinking about it, and surely there is a trade off between fast gas flow (through a smaller but flowed and flat surfaces removed hole) and more but slower gas when it is bored out. Or have I done my usual and gone off on a complete tangent :lol:

 

 

The flow rate of fluid through a system is the same at all points if the density of the fluid remains constant.

 

The fluid here is air, and although you could argue that the density changes as the air inlet temperature is slightly increased, this is negligible for modelling an engine inlet system as such a system.

 

This is governed by (rho).A.c remaining constant, where Rho is the greek letter symbol for density, A is the area of the pipe the fluid is flowing through and c is it's mean velocity in m/s.

 

:D

[boost monkey 0]

backside

 

 

Ive decided to refit the wedge so will se how it drives tommorrow

 

You should really take out the spindles and knife-edge them too, fluids prefer to flow down the middle of a pipe as opposed to the 'boundaries' along each side.

 

Take the screws out aswell and flatten off those god-awful rounded heads, then it'll be awesome :thumb right:

[boost monkey 0]

i was lucky doing the rear, i cut the top off the inlet mnanifold and flowed that, then bolted the tb to it and marked out the tb line in the inlet manifold if that makes sense?

Basically port matched the tb to the inlet.

 

 

It would be so much easier if your were using flap wheels, that bit you wana cut out the half moon on the divider, that shape just appeared on mine whilst i was using the flap wheel

 

I even read somewhere that some people using a different injector in number 4 cylinder as airflow to it is so restricted, they dont want that cylinder running too rich :shock:

Think that air as soon as its gone through your tb, has to take a sharp right angle to go down number 4 port.

 

That's very cool :D

 

If you modelled the inlet manifold TO SCALE on a computer (finite element analysis?) and you knew the intake air velocities at certain rpms , I reckon you could work out which injector to put in each cylinder at a particular duty cycle to give a perfect AFR.

 

Obviously, manufacturer's don't bother with this at the factory! :lol:

[boost monkey 0]

oh yeah, as Daz said injectors are batch-fired so scrap that.

 

But if you could fire them individually it would be complete intake control.

[flusted 0]

I put counter sunk screws in my spindles, didnt want to thin the spindles out though as scared at forces that would be pushing on them

[boost monkey 0]

if you know the material the butterfly, screws and spindle are made from, and the peak air velocity in m/s through the butterfly I could calculate the minimum safe thickness you could have the spindles if you like?

 

or is that too geeky? :lol:

[JMC 0]

Thread revival.... Finally got round to putting the throttle body back together (after figuring out how it all fitted). Just in time for the new engine next week :D Probably make no difference whatsoever, but heh, it was fun to do :eek:

[flusted 0]

looks pretty good although you could of gone higher with the knife edging up to the outer part. great finish

[JMC 0]

looks pretty good although you could of gone higher with the knife edging up to the outer part. great finish

 

Yeah, I thought about that. Problem was at the time I did that bit all by hand with a file and wet and dry paper. With hindsight I should have done it using a dremmel, it would have been sooo much easier.

[a98pmalcolm 0]

im goin in for work on the 12th at jabba and getting them to port out my throttle body a bit while its there, did u notice anything much by doin this work? im thinking it will for my G60 as im running 22psi of boost

 

will be good to know ya thoughts on the final result with the work u carryed out?

 

thanks

 

paul

[corradog60stage4 0]

any flow figures?

this looks pretty interesting.

my TB is holding back

[JMC 0]

To be honest it was fitted along with my 1.9l engine conversion so I can't say what the throttle body has done by itself. The general consensus seems to be that they flow better, but as for adding any power there is little to say they do that.

[corradog60stage4 0]

well i started to tinker with a spare tb with some flap wheels.

 

 

 

 

 

[flusted 0]

lOOKING GOOD

[Cheapmods 0]

i noticed mr. stage4 has the gasket still on his, which made me wonder what everyone else has done... Was there any enlarging done in that area or just smoothing? It's quite obvious that everyone enlarges in inlet portion.

 

Also, on the tex, i just read over a post about intake manifold porting. It was mentioned that if the mani could be lengthened it would give better flow to cyl 4, as it's such a dramatic turn for the air to make.

[corradog60stage4 0]

i noticed mr. stage4 has the gasket still on his, which made me wonder what everyone else has done... Was there any enlarging done in that area or just smoothing? It's quite obvious that everyone enlarges in inlet portion.

 

Also, on the tex, i just read over a post about intake manifold porting. It was mentioned that if the mani could be lengthened it would give better flow to cyl 4, as it's such a dramatic turn for the air to make.

 

the only way to do it correctly is to get an audi 5000s turbo manifold and modify it like I did.

 

 

 

 

 

 

[thermal 0]

if im not using the isv nor the carbon canister etc, is there any need for lower butterfly?

 

can i cut it off and weld it up? shown in red

 

[corradog60stage4 0]

if im not using the isv nor the carbon canister etc, is there any need for lower butterfly?

 

can i cut it off and weld it up? shown in red

 

 

 

well i left it there but it vents to the atmosphere

[Richardshoes 0]

if im not using the isv nor the carbon canister etc, is there any need for lower butterfly?

 

can i cut it off and weld it up? shown in red

 

 

Hi,

You can weld it up and block the lines, however you will over boost the engine, creating a pressure spike and then doing some damage. The bypass butterfly valve is to bypass boost at low loads, full boost only comes on a few degrees before fully open throttle. Also, No ISV will create an overboost condition again.

[steveo29 0]

no dont weld it up :shock:

[JMC 0]

If you cut off the lower butterfly as indicated in your diagram and weld it up, all of the charger air will be forced into the engine all of the time. Not good. You can cut off and weld up the small pipe coming off the lower butterfly if you have removed the carbon cannister though.

[thermal 0]

If you cut off the lower butterfly as indicated in your diagram and weld it up, all of the charger air will be forced into the engine all of the time. Not good. You can cut off and weld up the small pipe coming off the lower butterfly if you have removed the carbon cannister though.

 

my dump valve will vent the air when the throttle is closed.

 

atm its constantly closed, and its very stiff when i try to open it by hand, so i doubt it opens on its own....