7875 + 5.9 + E85 + Megasquirt

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The trans is old. I’ve been running it for about 8-10 years. It probably needs to be freshened. Converter is new. Circle-D , built for boost though it’s possible it’s not up to the task.
The fact that there is no rpm drop on the log shows that the converter is not pulling the engine down after a shift. If the trans is slipping the fluid will be absolutely smoked. Are you making more power than circle d was aware of?
 
Duty cycles climbs from 10% at launch until 67% at the end of the run. It's hard to see rpm drop during the shifts. There is a spike to 6500 and drop to 6000 where the 2-3 should have happened but it could have been wheel spin or the trans slipping. I don't have an easy way to log shifts in the Megasquirt but I'm sure it could be done with some kind of output on the shifter.
Not sure what my next move is. I wanna go faster. I'm teetering between pulling this whole platform out and throwing in an LS or dumping a bunch of money into this 727 to give it a trans brake and necessary upgrades to support that.
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Does look like converter, but still check the trans pan.

I could have a forged LS and built 4l80 for the money I’ve sunk into my trans/converter alone. I wish I did. If I could get 1/2 the money I put into my engine/trans I’d make the move yesterday.
 
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Does look like converter, but still check the trans pan.

I could have a forged LS and built 4l80 for the money I’ve sunk into my trans/converter alone. I wish I did. If I could get 1/2 the money I put into my engine/trans I’d make the move yesterday.
That’s exactly where I am. This somewhat low dollar Magnum build has really delivered but I don’t feel it can go a whole lot further reliably.
 
Fluid is pristine clean at the dipstick. Not ready to drop the pan just yet. I was about a qt and a half low.
 

Are you using the thicker hygard? I think there is the low viscosity j20d and I think the thicker(standard) is j20c
 
Are you using the thicker hygard? I think there is the low viscosity j20d and I think the thicker(standard) is j20c
I’ve been using this Lucas stuff.
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I went back and looked at some of my older runs and the overall conclusion is that this converter is slipping to the tune of 28% which is pretty high. I don't think it's a lack of fluid issue.
tc_slip.png
 
Could/would circle D take a look at your data and rework the converter for you?
I sent them a message already. They’ll rework it I just want to know what the original specs are before I send it back and spend a bunch of money. It was built for my buddies high hp turbo application before he switched to an LS so I’d expect it to be up to the task.
 
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