Throttle plate mod

[Eslhockey92g]

Originally Posted by old_master

1996 and newer all use OBDII

Awesome I'll give it a shot suring my spring break
Thanx

[nickledimed]

Originally Posted by herkyhawki

Please take another look, take some pictures, take some measurements, do the math (hint 1/4 =25%), take some asprin, sleep it off, and then tell us all if it really blocks off 1/4 of the throttle body area. Please, I'll be waiting.

wait no longer...if had looked at the pics in the links before you stuck your foot in your mouth you wouldnt have posted this...also if had done the mod you wouldnt have made yourself look stupid.

here is your sticking pic.
http://www.sshotrods.com/fullsize/4.3/tb/

[nickledimed]

Originally Posted by old_master

You're on the right track here.

This modification can not and does not affect engine RPM at any given speed. Whatever engine RPM at any given speed was before the modification, will be the same after the modification. If you want engine RPM to change, a gear ratio must be changed.

What this modification does accomplish, (besides void the warranty) is reduce air turbulence, and air velocity, while at the same time increasing air flow. Any time a restriction is introduced, the velocity will increase and flow will decrease. The shape of the "baffle" on the throttle plate causes a "venturi" effect, just as the throat of a carburetor narrows down inside. In this case air turbulence is desired. The fuel is introduced at the point where the air is moving the fastest to atomize the fuel. With fuel injected vehicles, the fuel is atomized by the injector spraying the pressurized fuel. Therefore removing the “baffle” will increase air flow allowing a smaller throttle opening, (less pressure on accelerator pedal). Both before and after the modification however, the OBDII system will maintain the desired fuel ratio so any difference in fuel mileage would be negligible. Removing the “baffle” may increase induction noise slightly. Low end performance / throttle response should improve, and may even prove to be too sensitive for the likes of some drivers. Hope this helps.

All I am doing is stating what is happeneing to my truck, maybe 550-600 rpm is the correct idl speed for my truck...I dont know. also I dont know if 2000-2100 rpm is the normal rpm while running at 70mph....all I do know is that before the mod, it was running around2300-2400 at 70mph. If you want to argue with my truck...go ahead....anyways when the computer was relearning how to make the engine breath again mabe some other factors were changed Like RPM and the such?
PS:....My truck is a 98= NO WARANTY

[BlazerLT]

The TB mod has been said to sometimes cause a leaning of the front cylinders in some cases, just be aware of that and note any pinging.

As for the MAF descreening, just don't do it.

The screen is there to straighten the airflow for a proper reading and the 4.3L MAF with a screen doesn't limit airflow. It is the same MAF they use on 454 engines and it is capable of not hindering airflow even when that huge engine is floored.

Descreening the MAF is a craps shoot, but the odds are you will have more problems after than before.

Just letting you know before anyone thinks that the descreening mod has no drawbacks.

[nickledimed]

Originally Posted by old_master

"If you want im sure there is some way to turn the rpms back down to 500."

Not true. The ECM is programmed to control idle RPM at a certain speed. It will adjust ignition timing and fuel mixture to achieve that speed. If it leans the fuel mixture or retards the ignition timing too far, engine performance will suffer greatly.

The ECM noticed a change and it is trying to compensate for it. That's why it's idling at 600 RPM. The longer the period of time since the ECM was reset, the longer it will take to "learn" the change, give it time. Once the ECM "learns" the change, idle RPM will return to where it was before the modification.

Ummm...Reprogram the ECM...is one way to adjust RPM.....Didnt I say that there has to be some way to adjust this?...I do think that reprogaming th ECM IS one way....isnt it?
REALY?...Its been about 1 week and its still idleing @ 550-600 rpm.

[nickledimed]

Quoted from someone else on a diffrent forum about this mod.
Try running the 100 yrd dash with one finger up your nose....

[joeuser742]

OMG, I can't believe that the manufacture would do this. Couldn't they come up with a better solution where the airflow isn't restricted at an open throttle? That piece of plastic is history as soon as I get the chance to do this. I just hope my wife doesn't have a hard time parking with it.

[maxwedge]

Originally Posted by BlazerLT

The TB mod has been said to sometimes cause a leaning of the front cylinders in some cases, just be aware of that and note any pinging.

As for the MAF descreening, just don't do it.

The screen is there to straighten the airflow for a proper reading and the 4.3L MAF with a screen doesn't limit airflow. It is the same MAF they use on 454 engines and it is capable of not hindering airflow even when that huge engine is floored.

Descreening the MAF is a craps shoot, but the odds are you will have more problems after than before.

Just letting you know before anyone thinks that the descreening mod has no drawbacks.

Absolutely true!!

[Jergin01]

I recently did this mod and the mass air sensor mod. Let me tell you for free and 25 min of my time, these are awsome mods. Im idling at around 600 rpms. My gas milage difinatly improved. Thanks for the awsome mod!

[BlazerLT]

Air sensor mod?

[nickledimed]

Originally Posted by joeuser742

OMG, I can't believe that the manufacture would do this. Couldn't they come up with a better solution where the airflow isn't restricted at an open throttle? That piece of plastic is history as soon as I get the chance to do this. I just hope my wife doesn't have a hard time parking with it.

I was wondring about the same thing about parking. Its not to bad realy after I got used to it, I usualy just idle back and if I need to give it a little gas, no prob....Have fun.

[Tangent]

Before I did this I was running at around 2300-2400RPM @ 70MPH, this morning on my way to work I was running 2000-2100RPM @ 70MPH.

I can understand this freeing up extra horsepower, but I'm at a loss to explain how this decreases rpms at any given speed...

Also it likely won't do anything for your mpg. While you'll be using less gas pedal to acheive the required horsepower to cruise at any given speed, you'll still be passing x cfm of air and the computer will feed the engine the appropriate amount of gas. (It doesn't matter whether you flow the 100cfm of air required for the 60hp you need at 65mph [just a guess] using 1/2 of a tiny throttle body or 1/10 of a giant throttle body)The only possible effect on mpg is the worse mpg you'll get at WOT because you can now flow more air which requirs more fuel...

[nickledimed]

who goes WOT? besides a racer?

[old_master]

Originally Posted by Tangent

I can understand this freeing up extra horsepower, but I'm at a loss to explain how this decreases rpms at any given speed...

Also it likely won't do anything for your mpg. While you'll be using less gas pedal to acheive the required horsepower to cruise at any given speed, you'll still be passing x cfm of air and the computer will feed the engine the appropriate amount of gas. (It doesn't matter whether you flow the 100cfm of air required for the 60hp you need at 65mph [just a guess] using 1/2 of a tiny throttle body or 1/10 of a giant throttle body)The only possible effect on mpg is the worse mpg you'll get at WOT because you can now flow more air which requirs more fuel...

EXACTLY! Couldn't have put it better myself! However, this will not even free up horsepower, it will modify low end throttle response simply by reducing turbulence. RPM cannot change, (read my earlier post in this thread). The RPM change that was referred to a couple of posts back, (changing from 2300 to 2000 at 70MPH) would be the approximate amount of change that the lock up torque converter causes at that speed.

[Cloud Strife]

Anyone else give this a whirl yet?