Chevy & GMC Vans

Simple throttle plate mod for newer vans to remove the restrictor plate. Performance gains are subjective, and will be unique to each van. I found an extra throttle plate from junkyard for few dollars to work on in case I screwed something up. I went at it from the interior side, so I removed the doghouse, not sure if you could do it from under the hood, didn't look like it to me. To remove the throttle plate you need to remove front air filter intake, then remove doghouse, then pop off the portion of the air intake mounted on top of the throttle body, and move it out of the way. Now remove the 2 torx screws, mine were size T15, you have to use a stubby driver because there won't be enough room for a normal size driver, be careful not to drop the screws down the throttle throat. I kept a telescoping magnet handy to snag the screws. After you remove the screws, use the linkage on the throttle body side to completely open the throttle, grab the restrictor plate and gently wiggle it until it breaks loose and slides out of the retaining rib. The more carbon build up you have, the harder it will be to wiggle out of the rib. Sorry no pics of the removal procedure, but it sounds worse than it is, once you have the air intake and doghouse off, it literally takes a couple of minutes to remove the plate.

This is a generic pic to show placement of the torx screws on the retaining rib


Once the plate is removed this is what you start with








Tools I used, Dremel and a hand file. The restrictor is made of soft aluminum and you could probably use your wifes gardening snips to cut it off


I fastened it in a vice to hold it while cutting


Then started cutting


Plate removed


Here is the material removed


I then proceeded to clean it up and bevel the aluminum edge with the hand file


I'm really trying to thin it out as much as possible






Finished product




Now all you have to do is re-insert it back into the throttle body, screw it in, put everything back together and your done.

i have also done this to my van, i did notice a little bit of a difference while accelerating from a stop, but this was back when it was stock...

unrreal wrote:i have also done this to my van, i did notice a little bit of a difference while accelerating from a stop, but this was back when it was stock...

Yeah, hard to say exactly what my gains were since I replaced a few other parts at the same time, but the getup does feel better from a stop, and it seems to shift a bit better too. All minor gains for sure but I would definitely rather not have the restrictor plate there

slim.. you are the king of tutorials my friend

crash wrote:slim.. you are the king of tutorials my friend

No way man, the king is chemist! He got to do all the hard ones like air filter box, fan shroud, alternator, water pump, coil, doghouse, and probably more. I've referred to his tutorials quite a few times while working on my van

This is intriguing. Does anyone know why the factory installed this 'restrictor'? Cold weather driveability, maybe?
Youth wants to know.

Ya know Jay, i saw a new hit on this thread and was scrolling down through the pics again and same question came to mind.
The thought came to my mind that perhaps with that baffle on the throttle plate, the air flow keeps the throttle plate from slamming shut when you have to slam on the brakes at high speed. I do just love conversations based on mutual ignorance. They can just carry on forever. So, Age wants to know as well. Where is Lifted or Mr Roboto when you need them? :-k

Well, I know that there has to be some kind of downside to removing it. I'm dying to know what the engineers were thinking.

That restrictor was used to slow throttle response. There is no downside. I did this mod several years ago. It does aid in quicker throttle response but you have to remember that our Astro/Safari vans weigh 4000 lbs. And they are only powered by 4.3 V6. Not exactly a hotrod. The real world results of this mod will depend entirely on the overall condition of your engine.

I am here but I am not an engine or trans guy...I do diff's, transfer cases and that sort of thing.

well pop my bubble...another of my delusions proven false. :-k

Sorry about popping your bubble. I am good at trans coolers and decent at shift kit installs and on engines I am good at basic maintenance items but no internals.