Been trying to find out if the throttle body diverter on the 4.3L V6 (X) can be removed without harming the engine in any way.
A few of these posts (TB stuff) were stuck under my "plugs and wires" post by mistake. I'm still new and learning.

Here are two opposing views,first from Blazer Forum; swartlkk

"I would not recommend completely removing the air deflector . Its primary function is to help turn the air towards the back of the intake plenum. With the TB so far forward on the intake plenum, it is necessary to help out the air flow to the rear cylinders. Plus it promotes a more even distribution of the EGR gasses to all cylinders. I have completely removed my deflector and am now in search of a replacement from a chevy 350 (same TB just 1/2 of a deflector). Now I haven't fully realized the additional air flow through the TB because that would require a larger MAF sensor as well."



Now from an e-mail I received from someone who works with throttle bodies as a business.

"The air diverter is only used to detune the motors, nothing more. Have gotten this straight from a GM power train engineer. Think of all the motors that have the throttle body on the front of the motor and do just fine - TPI, LT1, LS1 just to name a few."

Both opinions seem plausable, now what to think. All help appreciated.

 

The real reason the diffuser is on there (among the ones I have listed) is because the same TB gets used on the 4.3L, 5.7L (350), and the 7.4L (454) vortec engines. The only difference between the TBs is the throttle blade and the TB machining. In the 4.3L, the throttle blade has a 5/8" diffuser. The 350 gets a 3/8" tall diffuser and the 454 gets a marginally larger tb bore with no diffuser. I did not mention this before because we were talking about it's function on the 4.3L v6.

When you look at the TB position on these motors (yes I have worked on all of these motors), the TB gets closer to the center of the manifold the larger the motor. So I guess you could say that both are true. The diffuser is there to detune the TB for smaller displacements as well as to help out with directing the airflow inside of the plenum.

*EDIT* - On a side note. Keep these things in one place. Do not cross post the same question in numerous places.

 

Hello Kyle,
I do not know why you locked my "Plugs and wires" out. I put in one of my last messages that because the subject matter had "morfed' in to TB dicussion that would be where to go for future TB stuff. Look at the chronology of the posts you'll see
I realized there was a disconnect between heading and threads and told people to go to new post on TBs.
I do not know how to copy and paste between posts or I would have done it already. I am trying to learn more about the Forum
every day.I am relatively new to posting so I am learning on the fly. I was surprised you could lock my posts (threads)
without me getting in to any badmouthing of anyone or any vulgarities.
If you really feel I am out of line for this Forum I will pull my membership and walk away............ Ernie1019

 

Ernie, I really wish you would allow PM's (from within your profile). Things like this should not be discussed in the open forum.

I locked the other thread because you have already started this thread. If you wish, I could delete this thread and reopen the other one. Doesn't really much matter to me one bit. But if someone is searching for the TB diverter thread, don't you think it is much easier to find if the title is descriptive of the content? Who would think a 'Plugs & Plug Wires' thread would have anything to do with a TB diverter?

Please allow private messaging if you would like to discuss this further. Until then, your other thread will stay locked for the simple reason that it did not . I do not wish that you leave, just that you abide by the rules. You did the right thing to post a new thread on the topic you wanted to discuss, now keep with it. Post up in the new thread, NOT the old thread on a different topic.

Oh and to copy & paste, simply highlight all of the text in the post in question and right click, then left click on COPY in the drop down menu. To paste it, start a new post in THIS thread and right click and then left click on PASTE.

*EDIT* - From with in your profile (top of the forum, 'My Profile' link)... Inorder to allow PM's, please make your profile public (ie. uncheck next to 'Hide Profile') and place a check mark along side 'Allow others to send you Private Messages'. You can still hide your email address and none of your personal information is necessary inside your profile.

I will not entertain any more conversations of this type in the open forums, that is what PM's are for. They do not belong here. Other mods will be brought in on this issue as to keep your interests at the forefront if you feel that I am slighted against you in anyway.

 

From this thread: Plugs & Plug Wires

The main difference between how the 4.3L SCFI (and 5.7L 96+ Vortec) is setup and the LT1, LS1, 3.8L v6, heck even the 4.3L CPI motors, etc is that these engines have the TBs facing horizontally into the plenum. With a vertically mounted TB, the airflow has a much more difficult time turning twice (once to go horizontal into the plenum and again to pull down into the intake runners to the intake valves) than it is for the flow to turn once (down into the intake runners) in the front mounted TB configurations. From an airflow standpoint, the pressure would be lower in the back of the plenum than it would in the front at any throttle position/operating condition. The diverter (funny no one has called it a restrictor yet) is there to help the air along it's path.

To say it's ONLY function is to detune the tb is simply not true.

If you don't want to listen to me then fine. I could care less. Go cut your blade off and see for yourself. Do the testing yourself. I for one am not going to drop the $25/pull on a dyno (that's what the shops close to me charge) for the real world results YOU seek. Not to mention that to get accurate dyno results you need to do atleast 5 runs per setup. You're talkin' $250 [sm=insomnia.gif]!! And that's only for WHP no sensors in the exhaust or anything of the sort. Those sessions cost $$$. You wanna pay for me to do it, be my guest.

My suggestion is you go and do this mod and form your OWN opinion.

I'll also add this little tid-bit. If you think that because it is SCFI with individual injectors for each cylinder and say that one or two cylinders cannot run lean, that is simply UNTRUE. You can have one or two cylinders on a single bank run lean so long as the other cylinders on that bank are running rich to make up for them in terms of the O2 readings. Basically, any engine that has 1 O2 sensor per bank for fuel management will treat all those injectors on that bank as a single injector as far as pulse width is concerned (not injector timing). So each one of those cylinders will be getting the same amount of fuel. Now decrease the amount of air to a cylinder (or increase the amount of EGR gasses - inert gas to any one cylinder) and you will have a decrease in the power output of that cylinder. Will this difference be perceivable? Probably not, but that does not mean that it isn't causing cumu