I just had an idea....(IP governor Mod + Run away throttle fix?)

[trav1856]

Why couldn't we do this to fix the problem of over-revving?

somehow, have an air-flow butterfly valve on the intake plenum that works in tandem with the injector pump, so that at idle it's cracked open (with a rest pin or something), and then at full throttle is of-course wide open, and if you break your wheels loose, let up on the throttle, it restricts the airflow, and can't make power, so it revs back down quicker. Thoughts? or am I just thinking totally wrong?

[R.O.R-2.0]

if your governor is adjusted properly, you dont get run away throttle..

just back your fuel screw out some, or if thats not enough, drop the coin on a giles pump..

and the system you are describing, is kinda like that of the system they used on the early MB's and datsuns..

[maxfax]

What Kevin said.. A properly functioning governor will take care of it..

The butterfly would be an air restriction that would lower the economy..  MB, Datsun, and IIRC some Toyotas did use a butterfly in the intake, but that was solely due to the design of the IP.. The governor worked off vacuum..  When he plate closed, the vacuum increased and caused the governor to decrease fuel..  The Bosch pump has centrifugal weights to take care of that..

[8v-of-fury]

I think the OP might be referring to the fact that if you are hard on the throttle and your tires break loose, your engine will spin to infinite (!!) and kaboom.. Or until the rollers in the pump skip. However, the butterfly will not protect from this anymore than letting off the pedal will..

As soon as you let of the pedal, like that instant, it will stop fueling and engine speed will decrease (due to wind drag, rotational losses) and wheel spin will stop. I mean sure it is very likely to overspin your engine.. but the pump will skip the rollers (weak springs in the pump) and cease to make power (no fuel being injected) thus it will not be able to spin over approx. 6000rpms. A 1.6 bottom and top end can spin 6000rpms no problem, a 2.0L can spin this rpm no problem. You have a higher risk of damage from missing a downshift and hitting 2nd.

[trav1856]

I think the OP might be referring to the fact that if you are hard on the throttle and your tires break loose, your engine will spin to infinite (!!) and kaboom.. Or until the rollers in the pump skip. However, the butterfly will not protect from this anymore than letting off the pedal will..

As soon as you let of the pedal, like that instant, it will stop fueling and engine speed will decrease (due to wind drag, rotational losses) and wheel spin will stop. I mean sure it is very likely to overspin your engine.. but the pump will skip the rollers (weak springs in the pump) and cease to make power (no fuel being injected) thus it will not be able to spin over approx. 6000rpms. A 1.6 bottom and top end can spin 6000rpms no problem, a 2.0L can spin this rpm no problem. You have a higher risk of damage from missing a downshift and hitting 2nd.

Okay, that's what I was wondering. Wasn't sure. Thought a butterfly might be an additional failsafe.

[745 turbogreasel]

ALH TDIs use an Anti Shudder Valve to set codes or something.

[R.O.R-2.0]

I think the OP might be referring to the fact that if you are hard on the throttle and your tires break loose, your engine will spin to infinite (!!) and kaboom.. Or until the rollers in the pump skip. However, the butterfly will not protect from this anymore than letting off the pedal will..

As soon as you let of the pedal, like that instant, it will stop fueling and engine speed will decrease (due to wind drag, rotational losses) and wheel spin will stop. I mean sure it is very likely to overspin your engine.. but the pump will skip the rollers (weak springs in the pump) and cease to make power (no fuel being injected) thus it will not be able to spin over approx. 6000rpms. A 1.6 bottom and top end can spin 6000rpms no problem, a 2.0L can spin this rpm no problem. You have a higher risk of damage from missing a downshift and hitting 2nd.

my car breaks the tires loose easy, and it doesnt rev up real high, just hits about 5600 (where the rollers start skipping) and stays there..

even when you delete the governor (shim it up so it cant operate) the engine still only turns a certain rpm..

and when the tires break loose, usually im right on top of it, and grab another gear to let the tires hook back up, or let out of the throttle a bit.. my foot is some of the best traction control ive seen yet..