Converter Problem/Question

[buzzinhalfdozen]

Maybe it's just me but from all the work you just described hell i'd have just thrown a converter at it . Problem solved or not it seems much easier than all the engine swapping and parts replacing. JMO. Joe

[Mark Yacavone]

Need more info:
60' time (before and after)

converter flash rpm

trap rpm

[Whalen3186]

From my experience, a bad converter will make you think its everything but a bad converter. We are kind of going through the same thing now.

[Kingpen]

as far as rpm-it never really has changed.it always seems to go to about 6100 rpm at the hit and falls to about the same on gear change,trap rpm is usually between 81-8300 rpm on 1/4 but most of my racing is done on 1/8 bracket track and trap rpm has been around 7000-7200..the 60' times have slowed along with the overall et...was always around 1.36-1.38-now you cant drag it any faster than 1.39-usually fall in the 1.4-1.42 range..the main reason I havent just put another converter in is (1) every time I done something with the engine was because it was usually freshen up time anyway & (2)it always stays consistent-just getting slower over time.

[Mark Yacavone]

There's only a few things that can go wrong with a converter. Most of them are very noticable.
If the sprag doesn't hold or slips off the line ,stall speed will decrease dramatically.
If the sprag slips downtrack ,it won't do it consistently, so the numbers in the middle will vary.
If a pilot thrust bearing goes away, it will increase the clearance between the pump and the turbine and the stall and trap RPM will most likely increase.
Same for broken fins , but you'd have to have more than one or two broken.
In the last three cases mentioned , you'd have metal everywhere in the trans and the whole deal wouldn't last long.
My guess: The converter is not your problem.

[7820]

In my case it was the converter and Mark figured out for me. I had all sorts of poblems at the Pontiac Heaven Race at Speedworld. Thought it was ignition related.....changed everything. Talked to Mark and he nailed it.....rolled the sprag. Took it out when I got home and yep......rolled the sprag. No longer have a sprag of that type...I now have a mechanical diode.

When I launched the car it would slowly accelerate. Instead of running 9.0's at 150 I was running 10.80's at 146.

Thanks for the help Mark.

[Mark Yacavone]

Originally Posted by 7820

In my case it was the converter and Mark figured out for me. I had all sorts of poblems at the Pontiac Heaven Race at Speedworld. Thought it was ignition related.....changed everything. Talked to Mark and he nailed it.....rolled the sprag. Took it out when I got home and yep......rolled the sprag. No longer have a sprag of that type...I now have a mechanical diode.

When I launched the car it would slowly accelerate. Instead of running 9.0's at 150 I was running 10.80's at 146.

Thanks for the help Mark.

You're welcome, and that's why we have a m/d in Alex Kadar's 455 GTO . Man, those 455's are tough on roller sprags.