Converter help!

[Jason Shepard]

I had a new converter made for me last August. Filled out the engine/car spec sheet and sent it over before building the converter. They set the stall at 6800. Put it in the car, and immediately was faster. Ran the car all last fall with no issues, it stalled right where they said it should. Around 20 runs later, into this spring, i couldnt get it to stall past 6400-6500. The car slowed down 3 tenths. I called, they said send it in.

In the mean time, ihad them build me another one, with new spec sheet. Built a new one that stalled around 7000. Immediately the car went back to running fast, maybe even a little faster. I called about the 1st converter, and they said they "really didnt find anything wrong with it" They freshened it and sent it back

After around 20 runs on the 2nd converter, stall speed is back to 6400-6500, and the car is 3 tenths slower again.

Both times, its a consistent slow. It doesnt continue to slow down. Transmission fluid is clean, no shavings. Line pressure is a constant 160. Running a metric 200.

Short version is, had 2 converters built by a VERY big name in converters, and had 2 failures after 20ish runs.

Anyone ever seen this before? Or have anywhere to start looking to find the root cause?

Thanks
Jason

[J.R. Haddad]

Hi Jason, J.R. I was shocked to read this. I was hoping your convertor
problems were behind you. For starters, I don't think that you were sent
2 bad convertors. They were both good to start with, then they both went
sour. I'm going to ignore that they didn't find anything when you sent the first one back, this problem is too unique for their rebuilders to identify. Some constant in your car is causing the problem, perhaps you have a bent front
shaft on your trans, or the bellhousing is off, or your flexplate has different
heights on the bolt tabs. I believe it is something like that. The best gentleman I have ever spoken to about convertor issues is Lenny at Ultimate Convertors. An extremely knowledgeable person, who treats his customers like they are family. He is the one race supplier that when he tells me
how much the bill is, I say, no, it must be more. Give him a call, you won't be mad. J.R.

[Jason Shepard]

Hey J.R. To say its frustrating is an understatement. I installed an Ultrabell myself over winter, but I bought it from Leo Glassbrenner. He machined the bell before sending it to me. He also went through my trans last summer and installed the transbrake. I put the 1st converter in at that time when he sent my trans back. The flexplate is a brand new JW piece that I installed after I broke the rear end in Rock Falls this June.

If alignment is off, wouldnt they have found some sort of wear inside the converter?

I will give Lenny a call....Thank you!

[1320racer]

Originally Posted by Jason Shepard

I had a new converter made for me last August. Filled They set the stall at 6800. Put it in the car, and immediately was faster. Ran the car all last fall with no issues, it stalled right where they said it should. Around 20 runs later, into this spring, i couldnt get it to stall past 6400-6500. The car slowed down 3 tenths. I called, they said send it in.

In the mean time, ihad them build me another one, with new spec sheet. Built a new one that stalled around 7000. Immediately the car went back to running fast, maybe even a little faster. I called about the 1st converter, and they said they "really didnt find anything wrong with it" They freshened it and sent it back

After around 20 runs on the 2nd converter, stall speed is back to 6400-6500, and the car is 3 tenths slower again.

Jason

With the 1st converter You stated “they” set the stall to 6800, did you check it and how are you checking it, then and now?

Also what is the weather data with the fast runs vs. the slow runs and lower stall? Are these fast runs and slow runs all at the same track?

[Woodfin]

Speaking of Lenny at Ultimate, I may be out of the loop but I though Lenny had sold to a long-time employee, Ragland. Is this correct?

And my experience with both Lenny and Ragland has been top shelf. Anything they have built for me has been exactly as expected.

[Jason Shepard]

Originally Posted by 1320racer

With the 1st converter You stated “they” set the stall to 6800, did you check it and how are you checking it, then and now?

Also what is the weather data with the fast runs vs. the slow runs and lower stall? Are these fast runs and slow runs all at the same track?

"They" being Coan. They built it to stall at 6800. I log everything with my Holley efi.

I compared my log books and weather data. When they were working correctly, weather conditions varried stall speed by 100-150 rpm. Same thing when stall speed was 500 slower.

I have had fast runs and slow runs at the same track.

[1320racer]

…….

[1320racer]

If you say so but it’s very hard to believe that you had 2 converters built by the same company and after the same number of passes they both loose the same about of stall rpm.

I say either your interpretation of your data is flawed or you’ve got another issue that is resulting in your converters loosing stall rpm. Do you have a data logger?

What does Coan say?

[Jason Shepard]

Originally Posted by 1320racer

If you say so but it’s very hard to believe that you had 2 converters built by the same company and after the same number of passes they both loose the same about of stall rpm.

I say either your interpretation of your data is flawed or you’ve got another issue that is resulting in your converters loosing stall rpm. Do you have a data logger?

What does Coan say?

I find it very hard to believe also. Im not placing blame anywhere, and its very possible something in my car is causing this. Im just looking for ideas.

Coan makes a ton of converters, and communication with them has been top notch. They didnt have any solid answers either.

I put converter #1 back in my car for this upcoming weekend, so I will see how it works.

Yes I datalog through my Holley. Converter slippage when it works is between 5-6%. When they are not working, its between 9-11%

[Proline]

Jason sorry im a little late to the party but i have had this exact problem and have a definite cure. Call 586-469-1140 this company makes a product called a Equalizer that will make ALL your converter problems go away.