throttle body
#1
08-20-2007, 01:07 AM
throttle body
a while back when i was playing around in my blazer the throttle got stuck when i shifted 3rd gear. i immediatly shut it off and cam to a stop. took my intake assembly off and found that the"thingy" on the bottom side of the TB plate had 99% of the way come off and was jamming the throttle open. the rivets that hold it in were still in it and it was only holding on by a fraction of the rivet. i have since then removed the part and put new rivets it its spot to close the hole it left in the tb plate. my question is what is the thing for ( looks like a orange slice lol) and will it do anything to my motor with out it. what was i ts purpose.?
#2
08-20-2007, 02:11 AM
RE: throttle body
No its a mod you can do it makes your throttle response better. I've done the same thing to mine. (Removing the baffle) It wont hurt anything.
#4
08-20-2007, 07:40 AM
RE: throttle body
If you run a search on 'diffuser' you'll find quite a few posts of mine on the subject. I had mine removed on my Bravada for over 2 years. While the throttle tip in (initial response) was MUCH more sensetive (to a fault), the wide open throttle performance was unchanged. I have scans showing the difference and it was miniscule. I was hunting for a 5.7L throttle blade & diffuser to install to see how the engine reacted. But without a free flowing exhaust system, this won't make a difference...
And yes, the main purpose of this diffuser is to help pull the EGR gasses to the back of the plenum for more even distribution. The 4.3L throttle body is located at the front of the intake while the 5.7L is closer to the middle and the 454BB TB is dead on center of the manifold. All of these engines utilize the same TB casting with the 4.3L and 5.7L sharing the same bore size, but with different diffuser heights (5/8" on the 4.3L and 3/8" on the 5.7L). On my Bravada, I noticed that the front cylinders were running rich (high quantity of spent exhaust gas inhibiting combustion) while the rear cylinders were running lean. This after running the truck in this configuration for well over a year.
And yes, the main purpose of this diffuser is to help pull the EGR gasses to the back of the plenum for more even distribution. The 4.3L throttle body is located at the front of the intake while the 5.7L is closer to the middle and the 454BB TB is dead on center of the manifold. All of these engines utilize the same TB casting with the 4.3L and 5.7L sharing the same bore size, but with different diffuser heights (5/8" on the 4.3L and 3/8" on the 5.7L). On my Bravada, I noticed that the front cylinders were running rich (high quantity of spent exhaust gas inhibiting combustion) while the rear cylinders were running lean. This after running the truck in this configuration for well over a year.
Thread
Thread Starter
Forum
Replies
Last Post
