I Shaved my TB Butterfly today!!!!

Well, I got our old guy Mech to do it for me....
He removed the restrictor plate in the TB and filled in the holes with a small nut and bolt with red loctite, and then tried to grind off as much excess as possible, and then center punched the bolt at the nut to stop it from becoming loose and ingesting it.

First impressions are a little bit quicker launch at normal driving conditions.
Just snappier driving around town... No real difference at WOT though...







I'm liking it!!!!!

Nice. Never heard of this? But then again I don't have a TBI.

It also applies to our Vortec engines. Since there really isn't an aftermarket throttle body that the L31 can upgrade to, like LS guys upgrading to 78mm or 90mm tb's, this is a small simple mod to help increase performance. The next thing to do is to port & polish it for a bit of added air volume.

Look here for more info:

http://marine-performance-parts.com/cfmtechportedthrottlebodyfor96gmtruckvortec5057.aspx

bai78 said:

It also applies to our Vortec engines. Since there really isn't an aftermarket throttle body that the L31 can upgrade to, like LS guys upgrading to 78mm or 90mm tb's, this is a small simple mod to help increase performance. The next thing to do is to port & polish it for a bit of added air volume.

Look here for more info:

http://marine-performance-parts.com/cfmtechportedthrottlebodyfor96gmtruckvortec5057.aspx

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That's exactly where I got the idea from! I just didn't want to pay $35!!!
I stumbled my way to that site while trying to determine stock cfm requirments for an electric fan on the intake.. turns out that's a bad idea!!! But like you say, the butterfly and bored out TB is a cheap mod!!!

Next up, I'm trying to get our local Unapco to machine my TB, but he wants a spare to practise on before he does mine. Where do I get a spare vortec TB??

It makes the 75mm an actual 75mm by removing the 72mm restriction.

Just driving it home tonight from work, I noticed that I didn't have to push as ******* the peddle to go as fast...

The vortec guys can put any LS based throttle body they want on it just has to match the intake manifold. Almost all LS based parts can go on a vortec and vise virsa. TBI's i dont know much about

Hmmmmmm .... $40 and I'm putting a new reman motor in this weekend....

99Yuk said:

Next up, I'm trying to get our local Unapco to machine my TB, but he wants a spare to practise on before he does mine. Where do I get a spare vortec TB??

Click to expand...

My guess would be ebay, cl, or a salvage yard.

AquinoSteven said:

The vortec guys can put any LS based throttle body they want on it just has to match the intake manifold. Almost all LS based parts can go on a vortec and vise virsa. TBI's i dont know much about

Click to expand...

How do we match the intake manifold? Unless we do a ramjet or some other aftermarket intake, we're stuck with the stocker right? There is no "bolt on" upgrade TB, correct?

Ported TB

Have any of you noticed any difference in fuel mileage with the ported TB and butterfly? or just response?
Kyle

99 2dr said:

Have any of you noticed any difference in fuel mileage with the ported TB and butterfly? or just response?
Kyle

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No, I didn't notice a difference at all. I only noticed fuel economy after I got the new crate motor installed, and after it was broke in, when I switched to full synthetic.

I clicked on that link and they now have a ported throttle body w/high throttle blade for $197. i just don't know if what you get in the end in terms of performance is worth it.