DIY port and polish TB

[MikeG]

I almost did something like that but I decided to just get some domed screws

 

[audio1der]

Could someone explain "half-shafting" and its benefits, for the rest of us?
NICE work! I would have done that had I thought of it; I found the benefits of my 87mm ported TB left me wanting, and with a hunting idle.

 

[PCA4208]

Half shafting is where you cut out half of the shaft that the throttle plate bolts into. Doing this along with knife edging the throttle plate and porting will help a lot. Not my pictures.
Here's before.

Here's after

 

[Appauldd]

I am curious..

What is the exact diameter of the throttle plate? Is it possible to port the throttle body to a point the throttle plate sits perfectly perpendicular to the throttle body? From the looks of the angle of the throttle plate it appears there is a lot of room to try this.

 

[PCA4208]

The throttle plate is supposed to be at an angle. Unlike LS engines or others, I don't thinks its possible to make it sit perpendicular to the throttle body. So in short, no. And if you port under or over the throttle plate, more air is making it in than its supposed to be, so idle would suffer.

 

[MikeG]

You could bore where the plate is like the BBK 90mm but it will not be a diy deal unless you have some very expensive tools. It would have to be done with CNC and you would have to make and re clock the plate. So if your not sure what/how to do that I wouldn't touch that.

 

[reddot]

them some nice balls you got. Awesome work they turned out as well.

 

[MikeG]

them some nice balls you got. Awesome work they turned out as well.

Hahaha I went a week trying to find the courage and finally got out the Coor's and other tools and went at it.

 

[Hornet]

LOL,i gotta get me some of them Coors.

For you guys thinking of doing this,but scared to tackle it,just about any old throttle body from your local wrecker makes a good throttle body to practice on,and see if you want to tackle doing this.

Just about any car with tuned port injection will have a throttle body that you can use to practice on.

I gotta say,i'm very impressed by yours Mike.
Rick

 

[MikeG]

Thanks. That's kinda what I did. I had the core TB off my wife's Ford Escape that I did a little practice on.

 

[UNBROKEN]

I wouldn't bother with going for a mirror polish. You'll gain exactly nothing for your efforts.
Since someone on this forum thinks my advice is full of ****....read up on boundary layers, laminar flow and turbulent flow. Those are some of the basics we looks at with the finish desired on port work. Google the terms I listed and decide for yourself....I can assure you though that you'll put in a lot of effort for zero gain.

 

[MikeG]

I wouldn't bother with going for a mirror polish. You'll gain exactly nothing for your efforts.
Since someone on this forum thinks my advice is full of ****....read up on boundary layers, laminar flow and turbulent flow. Those are some of the basics we looks at with the finish desired on port work. Google the terms I listed and decide for yourself....I can assure you though that you'll put in a lot of effort for zero gain.

Laminar flow in a straight pipe may be considered as the relative motion of a set of concentric cylinders of fluid, the outside one fixed at the pipe wall and the others moving at increasing speeds as the centre of the pipe is approached. Smoke rising in a straight path from a cigarette is undergoing laminar flow. After rising a small distance, the smoke usually changes to turbulent flow, as it eddies and swirls from its regular path.




So if I understand this right. It doesn't really matter how smooth the wall is since the air is riding inside the air

 

[UNBROKEN]

And a boundary layer will help flow along a wall....since air speed on a wall is zero having a buffer there will increase airspeed along the wall....which in turn speeds up everything else.

 

[MikeG]

Got it. Thanks for the info.

 

[JohnHenry]

Awesome thread OP! My Dodge TB is plastic but still went ahead and same principles apply.

 

[MikeG]

And a boundary layer will help flow along a wall....since air speed on a wall is zero having a buffer there will increase airspeed along the wall....which in turn speeds up everything else.

By buffer do you mean that lip that was on thère?

Should I put it back ?

 

[UNBROKEN]

No, I meant the boundary layer of air acting as a buffer between the flowing air and the stationary wall.
It's the same reason fast boats have rough hulls...it puts a boundary layer between the hull and the water...letting the boat move with less resistance.

 

[MikeG]

aaaah I see said the blind man. I was just reading that.

Since we are on this great topic. Do you think i would benefit from opening up the intake (Plenum) and matching the TB to that ?

 

[UNBROKEN]

aaaah I see said the blind man. I was just reading that.

Since we are on this great topic. Do you think i would benefit from opening up the intake (Plenum) and matching the TB to that ?

If your taper in your bore left a lip when you bolted the TB back on then yes, a port match will help you out.

 

[MikeG]

Thanks for all the info UNBROKEN I really appreciate it.

Back to the Coor's this weekend for some tweaking to my TB and intake.