Motor is and strocked and punched out to a 505ci , brodix bb2 xtras 355 c and c head ... 800lift vam by bullet...super victor and a 1250 donimator ...dyno pulled great Max power was 7600 rpm 906 power ... I need to buy a new converted to go behind this thing and don't know what stall or size .????? Its a tci 400 ..transbrake ... Reversed valve body ... That's all I know .... And help should be awesome!

 

And its 13.5 to1 compression

 

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YOU dont pick a converter.. YOU need to call a shop like PTC, Neal Chance, Pro Torque, Circle D, Yank.. they will set you up correctly after getting all the info you just posted. It will be pricey, probably $800-1300. Goodluck! That is a lot of power!

 

This is a easy one! Call a good converter company and be ready to answer alot of questions. The more info you can give the better. So know everything from cam specs to tire size. We use fti and ptc in all our racecars. They are both good companies and have great customer service. You get what you pay for.

 

I used greg at fti also. He did a great job.

 

For best performance, the stall speed should match the cam grind. If you don't know the cam specs, the converter companies won't be able to determine the best stall speed to use.

Since you have a dyno sheet, that's just as good and more preferred since it will show the HP and torque curve of the engine.

As above, expect to pay around $1000 for a converter and my guess will be that is stalls somewhere around 6000 rpm.

I got my race converter from these guys
http://www.tcsproducts.com/

 

Here's the thing about cam information. When you're talking about a full race car with 13.5 CR, 355 heads, 7500rpm peak HP, 1200 dominator and .800+ lift the aggressive duration #'s are implied. After seeing that combination there's nothing that would sway a TC Builders decision from building the loosest possible converter the application will allowed. I guess what i'm trying to say is that whether he has the cam card or not the converter will still be the same spec...Max loose.

What's more unpredictable is a street car. Guy says 383 with 195 heads, 750 carb, 11.1 pump gas etc... The cam will determine if we're talking about a 1800-6200 rpm motor or a 4000-7200 rpm motor.


The car above in question would probably make a unicorn pass with a 6100-6300 stall 8". If it's real heavy than maybe 5900-6000

 

Max loose to me would mean the car might not ever be able to move itself..... im thinking the converter builder needs to get an idea of how much torque you are making and at what rpm. He will also consider what kind of racing the car is doing, what weight, what kind of tire, and whether or not it will have a power adder. He will reference similar combos he has done in the past as well.

 

No, by max loose I don't mean that the converter will be built so loose that it won't move, lol. I mean that the stall speed will be be at it's peak for the combination. 6100-6300 would be that number. Backing it up to 56-5900 would not be the loosest the combo will allow. It will be a little conservative.


Converter builders will do a converter for the combo above sometimes as much as 2-3 times a day. The information that was posted gives a very clear idea of what the torque peak looks like in that application. Aggressive, N/A, Big Block Chevy's with that setup almost always make peak TQ between 5300-5600. In this case that motor could peak as high as 5800. General rule of thumb is converter stall speed 300-500 RPM's over peak TQ.

I'm assuming with 13.5 CR, .800 lift cam and a Trans brake this is a drag application. What kind of tire makes no difference on where the stall speed should be at the 900hp power level. It really shouldn't make a difference at all in any N/A application. No Power adder was mentioned.


Yup, This combination is like Strohman bread being white to a converter builder.