Normal For A SHO to Rev Down Slowly?

[aaronsbiza]

I have a 95ATX. When I rev the engine it will rev up fast, but when I release the Gas it revs back down to idle pretty slowly. I would expect that the decelearation of the engine would be quick and snappy. Am I mistaken? I have never driven another sho so I don't know if that is the way it should be. If that is unusal, would that be a sign of a blocked cat?

 

[Bluto]

The only time the engine will "rev down" quickly is if its under a load. ie lower gear, towing something.

 

[Mr Anonymous]

It's the inertia from the torque converter. If you don't rev the car in park or neutral (I've never understood why people do this anyway...), you won't have the problem.

 

[aaronsbiza]

Out of the many cars I have owned the SHO revs the slowest when coming back down to idle. My neighbour told me that this is a symptom of a blocked cat. He explained that the engine reved down slowly because there is a lot of backpressure present, thus slowing the speed at which exhaust can be exhaled, thus slowing the rev of the engine. He saide it did seem a little sluggish and that it may be a clogged cat. Any Opinions?

 

[yamahaSHO]

aaronsbiza:
Any Opinions?

Yeah, if you think the cats are bad... CHECK THEM and see if they are.

 

[aaronsbiza]

What are other symptoms of a clogged cat?

 

[jthomas68]

The rate at which the rpm`s come back down is computer controlled.You can actually change that function with the EEC Tuner.

 

[shojuan]

aaronsbiza:
Out of the many cars I have owned the SHO revs the slowest when coming back down to idle. My neighbour told me that this is a symptom of a blocked cat. He explained that the engine reved down slowly because there is a lot of backpressure present, thus slowing the speed at which exhaust can be exhaled, thus slowing the rev of the engine.

Sounds like bs to me.

 

[haydenm315]

I replaced my ypipe with a performance plus unit that came with the high flow cats. My car revs down slow as well. I always though it reved down slow due to a heavy flywheel. I don't think atx's have flywheels though I may be wrong.

 

[RJ-92]

aaronsbiza:
Out of the many cars I have owned the SHO revs the slowest when coming back down to idle. My neighbour told me that this is a symptom of a blocked cat. He explained that the engine reved down slowly because there is a lot of backpressure present, thus slowing the speed at which exhaust can be exhaled, thus slowing the rev of the engine. He saide it did seem a little sluggish and that it may be a clogged cat. Any Opinions?

Wouldn't excessive backpressure cause the motor to rev down quicker? The more backpressure the harder the engine has to work to blow out the exahust gass causing low RPMS once lifted off the throtle. Kinda like an exahust brake on a diesel.

 

[svtman]

Wouldn't excessive backpressure cause the motor to rev down quicker?

Egg-zactly. An engine is a pump and if there is a restriction at the exhaust end it will limit engine speed and cause it to decelerate quicker than normal.