racing with too tight converter?

[rtviper]

What would be the repercussions of racing with a converter that has a too low stall? With a motor with lots of power over 1000 hp for example and using a trans brake what could one harm with several launches on a 2800 stall? The converter is a 9 inch that was reworked to about 2800 and I want to make a few passes before I change it out. The converter was designed for high HP but re-stalled to the 2800

 

[Red C5]

Ok, I want to see some pics of the beast.

 

[SPOOLFOOL2]

Not sure that you would hurt anything. You'll just bog the motor to below the power band.

 

[GNVYUS 1]

It's going to go past 2800 on the trans brake with that setup and who's 9" is it, Art Carr?

 

[rtviper]

Yes it was an Art Carr 9 inch. The previous owner had it reworked to more streetable 2800/3000 stall. I was trying to determine if I could do any harm to the drivetrain. The car was unable to get the power to hook with the previous stall of 5k so he decided to just make it more streetable.
I will try a pass or two and see what happens

 

[GNVYUS 1]

Keep track of your trap rpm so you can figure out your converter efficiency. But with your setup you might want to talk to Dusty about a PTC and even a bolt together if you start dropping into the low 9's etc.

 

[Smokin-6]

With a 1000 HP anything could break Yes, lets see some pics

 

[rtviper]

Thanks guys I will take some pics and post

 

[Alky V6]

I don't think an art carr will hold that 2800 stall with that HP. It most likely will be higher than that. If it truly is that tight with your engine you can expect a large rpm drop between shifts and a harsher shock to the drivetrain during the shift. The drop in rpm on the shifts will tell you how well the T/C is handling that HP. Depending on how far past peak hp you take the engine before shifting, if the T/C is truly tight, you should see rpm drops well past 1,000 rpm. A 1,600 rpm drop would be more like it.

 

[Dusty Bradford]

Just like Don said.

A converter that's too tight will have slow 60's due to the combination not being able to build boost. The rpm drop will be excessive and possibly pull the motor out of it's rpm range as well as shocking the tires to the point of loosing traction at the 1-2 gear change. You can shift the car early if you find it's dropping to much on the gear change. I have seen 1400 rpm drops not hurt a turbo car because they like the load but if you make a lot of power on a small tire it can cause you to loose traction.

 

[rtviper]

Thanks I will give it a try and see how it works out. I do know I replaced a too lose converter in my stage car with a 3600 stall from 4500 and picked up 3/10 and 8 mph with 2 lbs less boost. I will short shift it at first then go up.
I will be contacting Dusty about one of his converters after the test run

 

[Dusty Bradford]

Thanks I will give it a try and see how it works out. I do know I replaced a too lose converter in my stage car with a 3600 stall from 4500 and picked up 3/10 and 8 mph with 2 lbs less boost. I will short shift it at first then go up.
I will be contacting Dusty about one of his converters after the test run

Get some good data and we'll go over what you need. Shift rpm, rpm drop and rpm at the finish line will give us a good starting point.