[legend89chopped]

In prep to turbo the 2.7 litre, I found these butterflies in the intake manifold to be nothing but a turbulence inducing menace. So, I decided to take them out. It seemed pointless to just unscrew the flappers and leave the shafts there, so I went all-out.

After disassembly of the vacuum actuator and shafts, I fired up the welder with some aluminium wire and filled in the holes left behind by the shafts. I ground everything flat, and now I have no obstructions in the intake.

I'm no machinist, but I think I did a pretty good job.:thumbsup:

Pic #1 is the before shot
Pic #2 is disassembled
Pic #3 is after welding and grinding

F.Y.I. these butterflies have something to do with EGR operation, but I'm not sure what. I'm using a full stand-alone engine management system, which is not going to use EGR, so this is what I did. I DONT KNOW WHAT WILL HAPPEN WITH FACTORY ELECTRONICS IF YOU DO THIS. It's possible that your engine could go too lean during EGR operation if this interfered with it, and you could end up melting something important.

 

[sam o nela]

Good work man...

You could also eliminate that plate altogether as well as some old school old school members had done in the past....

Of course, if someone wanted flow, the 2.5 manifold is also a "possibility". Damn...I REALLY need to do that comparison already!!

 

[Muffo]

thats a dam nice job, i gotta learn to weld

 

[legend89chopped]

I thought about removing it completely, but it seemed to be a good spot to drill some ports later for a dry shot of nitrous. Plus, since I'm boosting, I'm not worried about trying to eliminate space in the manifold, I just need to reduce turbulence.

Plus, this was way more fun than just removing the thing.

 

[jago]

not a bad job at all.

according to the manual, they are actually for increasing the low end torque,

 

[legend89chopped]

Yeah, they open up at lower engine speeds to take advantage of the high-rise style manifold. They have to be shut when EGR starts pumping in exhaust gas for some reason. Oh well, screw EGR, I don't need to save gas anyway. This motor will never see lean a/f mix again anyway.

 

[Redhawk9274]

I did the same thing. I lost low end torque. 3800 and up is noticeably more powerful. It would be a bad idea to remove the plate completely. This and a cold air is the best combo i have come across.

 

[acuralegend_racer]

i know this thread is old but... if your setting up a stand alone ecu then wouldnt these butterflies be in the way and cause problems because they will no longer function without the stock ecu? or can they be program to work with the stand alone ecu?

 

[1990Legend_LS_5spd]

programmed to work or just run off a mirco switch at a certain throttle position..

 

[acuralegend_racer]

programmed to work or just run off a mirco switch at a certain throttle position..

i dont understand, please explain in detail.

 

[ATXlegend49]

how would i go about just polishing my intake manifold? i want it to look spankin new

 

[C27A1Legend'88]

how would i go about just polishing my intake manifold? i want it to look spankin new

You mean just the outside. It is aluminum I think. I know about a good site that shows how to polish aluminum.

 

[ATXlegend49]

yes just the outside. i saw one the other day that look maaaaaagnificent and i was pretty jealous. really its aluminum??

 

[C27A1Legend'88]

Yes the whole engine is aluminum. So the intake is probably aluminum too. It would just make sense. Do you want me to post the site that shows how to polish aluminum?