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-   -   Converter company suggestions for my application (https://classracer.com/classforum/showthread.php?t=77741)

Brad Hawk 11-01-2020 04:35 PM

Converter company suggestions for my application
 
I'll put the car back on the track w/ the current -- and old -- Dynamic (Lupo) 9.5" piece that was in the car previously to get a baseline w/ the new engine combination. With that combination, it would flash to approx 4500 from a 2000 launch and showed about 8% slippage on the big end (1/4 mile).

Being a dual-purpose car, I don't presume the converter can be set "on kill" and still actually drive the pig to the track. However, my expectation is I'll be getting recommendations to go w/ a tight 8".

The torque peak's moved up from about 4900 to 5100, and the HP peak has moved up from 6300 to 6800. Power-wise, the torque curve has picked up across the full 3500-7200 dyno pull range and the peak HP is is up about 60 HP. Trap RPM will probably increase from 6800 to maybe 7200 now.

It's a BB Mopar (440 stock-stroke), and a number of BBM bracket racers were using Ultimate w/ good results before Lenny sold it (to one of his former employees, IIRC).

I really don't have any complaints w/ Dynamic based on how the 9.5" has performed, but they haven't even updated their website in 10+ years. I have no sense for what they're doing today or what their rep is now.

Have never used ATI, but I could drive there from where I live in Northern Virginia and talk to them face-to-face, if a better approach than over the phone. I have talked w/ their reps at the track, but not in many years.

Also not against going somewhere else, so any feedback or thoughts as to what converter company might have a better handle on a combination like mine is appreciated. FWIW, it's approx 3800# w/ driver and should pick up noticeably over the old engine that was good for mid-to-high 10s as driven to the track.

My apology if this post seems to bounce around in terms of how info is presented. Thx - Brad

NHRA1926 11-03-2020 01:50 PM

Re: Converter company suggestions for my application
 
Call Ultimate Converter Concepts and talk to Montgomery. He is now running the operation, and I believe he has worked for Lenny and Dawn for a number of years. I'm sure Lenny wouldn't have turn over is successful business to any one that wasn't as good as him. I have talked to Montgomery, and he is as nice as Lenny and Dawn. I am not at all hesitant to use Montgomery. He helped me through a possible issue with my current converter (which came from them) when switching to a power glide transmission from a turbo 400. I will be sending my converter back to them in a few weeks.

Tex013 11-03-2020 05:18 PM

Re: Converter company suggestions for my application
 
ya know Brad .
I have a Dynamic 9 1/2 flashed to 4800 with 440 , 5000 behind 505 and was fine daily driving and and interstate .Now I have an A1 behind my 505 it is 6000 again been fine daily and interstate .
I did also have the A1 behind my 440 for a while when i split the 505 stock block .
A converter is always a bit of a cross your fingers and also how much of a compromise you can accept .

Bit like ordering dinner in a dark restraunt in a foreign country .


Tex

nickh 11-10-2020 08:52 PM

Re: Converter company suggestions for my application
 
Have had great luck with Circle D, would recommend them to anyone.

Mike Rietow 11-13-2021 12:53 AM

Re: Converter company suggestions for my application
 
Quote:

Originally Posted by Brad Hawk (Post 627075)
I'll put the car back on the track w/ the current -- and old -- Dynamic (Lupo) 9.5" piece that was in the car previously to get a baseline w/ the new engine combination. With that combination, it would flash to approx 4500 from a 2000 launch and showed about 8% slippage on the big end (1/4 mile).

Being a dual-purpose car, I don't presume the converter can be set "on kill" and still actually drive the pig to the track. However, my expectation is I'll be getting recommendations to go w/ a tight 8".

The torque peak's moved up from about 4900 to 5100, and the HP peak has moved up from 6300 to 6800. Power-wise, the torque curve has picked up across the full 3500-7200 dyno pull range and the peak HP is is up about 60 HP. Trap RPM will probably increase from 6800 to maybe 7200 now.

It's a BB Mopar (440 stock-stroke), and a number of BBM bracket racers were using Ultimate w/ good results before Lenny sold it (to one of his former employees, IIRC).

I really don't have any complaints w/ Dynamic based on how the 9.5" has performed, but they haven't even updated their website in 10+ years. I have no sense for what they're doing today or what their rep is now.

Have never used ATI, but I could drive there from where I live in Northern Virginia and talk to them face-to-face, if a better approach than over the phone. I have talked w/ their reps at the track, but not in many years.

Also not against going somewhere else, so any feedback or thoughts as to what converter company might have a better handle on a combination like mine is appreciated. FWIW, it's approx 3800# w/ driver and should pick up noticeably over the old engine that was good for mid-to-high 10s as driven to the track.

My apology if this post seems to bounce around in terms of how info is presented. Thx - Brad

You want it to stall through peak torque because below stall it'llmultiply the torque by as much as x2 depending how aggressive the stator installed. So this means at the least 5200 stall, with a three speed transmission.The sprag converters I've worked with which multiplied torque on the high side of the range below stall, were a little less efficient down track, but that's ok too, if ya wanna cross 7200 rpm.


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