Help please : Problem with bigger throttle bodies ?

[Doug Supercharged Vipers]

The ECU reads the "MAP" sensor voltage and converts it into usable input.

A few things to consider:

When you open the throttle bodies it will slow down air velocity. Yes, you can assist this modification opening up the heads and exhaust.

The ECU may need more time to relearn this change.

It's very important to check the synchronization of your throttle bodies.
The left side MUST lead the right side or both sides be exactly even.
Anything less will cause severe drivability problems.

Hope this helps,
Doug

 

[Fred(DrivingSchool)Kinder]

Bigger T. Bodies may lower performance. I have a modified motor and on an engine dyno saw no benefit from bigger T bodies. On a stock motor things(hp and torque) could go south.

 

[Jerry Dobson]

There are posts about Loss of power with the larger throttle bodies. Usually it will take a Cam, Heads, and Headers for the benefit to take place at high RPM's.

**** on a straw, then **** on a toilet paper tube, get the picture causing the loss of power?

 

[SingleMalt]

??? Anyway - Now that you've opened up the throttle bodies, you're (naturally) seeing less torque because the air is not as turbulent into the cylinders. When you add headers to that, guess what (assuming they've been designed for flow)? You're going to lose more bottom-end. Sorry. I've done this with a LT4 Corvette and have seen just what you're describing. Like Jerry says, the intake setup (manifold, heads, cam, throttle bodies, exhaust) are really a matched set...

 

[jp]

Try to get a set of stock TBO:s that's the only way to solve your problem. And make sure the the lip inside the intake, just behind the TBO:s, has a sharp edge.

 

[Larry Macedo]

You may want to also have someone completely depress the accelerator pedal while you look at the throttle blades to ensure they are fully opening. The early RT's had a problem with the cable housings moving and a TSB was initiated to keep this from happening. The parts are available through Dodge or you can find some washered screws to lock the adjusters in place.