My Cummins 6BT Story (1 Viewer)
- Thread starter turbophil
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Hit the nail on the head with this one!
I would think that getting a lower stall converter would add even more stress to the flexplate. I run a 1200 stall converter with my 4BT with only a 700R4 behind it and in my opinion the lower stall TC helps keep the tranny from building extra heat. Since the Cummins makes peak torque in the 1600-1800 rpm range having a low stall should make a noticeable difference in your mileage and power. Hope you guys can find some flexplates that won't crack! I'm not sure if mine is a stock one or not.
That’s funny when I contacted him to see if he could sell me a new one he said. It’s the first he had ever heard of such a failure....
Well. I’m making replacements now for how ever many of his first iteration users are out there if they fail I’ll make more changes. $200 flex plate is better than a whole new adapter
300-400 is all they said they could do. They also had a HD lockup which is what is driving the sudden change. Cold weather lockup was not happy. Even with temp off sets in the tables. It took a long time to get happy.
Flat ground foot on the brakes moderate throttle would give about 2200. That’s the bench mark we will measure the change from. But from having both stock and an adjusted converter in the past there is a lot more to it. Just better transfer at lower rpm to feel tighter than that even though the stall might not be supper low. It will still move nicely unlocked at 1500-1600rpm and pull.
Wha
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Dude we have covered this several times
I understand you have the newer style that uses more dodge parts and only a custom bellhousing. His early style used custom adapter plate on the engine stock Toyota bell housing with his own flexplate flywheel combo and a 6.7 ford starter.
He made the flex plate with a coining press and custom tooling that he told me he no longer has. But frankly wouldn’t want another with known issues. so I researched flex plates and designed my own to fit this adapter profile.
Thanks for your interest on the subject we know your truck is the cats meow getting. 30mpg with 1000hp pulling 100k lb big rigs out. (Hope you know this is sarcasm, but I would like to keep this more on subject)
So here are pictures of the set up
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Roadrunner Converters in Phoenix seem to have a good setup. foot on the brake foot into the throttle stall didn't change that much but the low end grab and power transfer is very different 1500-2000rpm. Enough that we have to modify the shift patterns since it's moving very well at lower rpm. The HD lockup was night and day difference especially under cooler trans temps.
Phil's original converter which we thought had never been opened up was sent back to Roadrunner to get the same modifications. When they opened it up the TC lockup was smoked and they indicated that the stall had been altered from original. This fact is interesting, we didn't know the history on Phil's original converter due to the Duiser diesel's questionable ownership during it's conversion. what we have to compare it to is the stock converter I put in mine after shattering my flex and tearing me modified converter that was always tighter than his 6 months ago. night and day difference between my modded converter by Dacco ( no longer in business) and non-modded original converter.
RoadRunner will further mod the converter for lower stall and install their HD lockup in this converter. I'll install this one in mine.
seems like some of the boosted 1FZ's could benefit from these mods. $250 plus shipping is small in the scope of power. just depends if yours makes power in the 1800-2300rpm range (our test we were spooling 15-20lbs of boost foot on the brake not moving in 1st, max boost is 33lbs if your trying to think back to dyno charts and HP and torque at those levels) . like I said under high HP the high end stall is still at the original 2200-2300 range of the toyota converter. just much more efficient below that point. I'd guess SC and turbo'd rigs could be more efficient with a tighter converter around town with TC unlocked.
Phil's original converter which we thought had never been opened up was sent back to Roadrunner to get the same modifications. When they opened it up the TC lockup was smoked and they indicated that the stall had been altered from original. This fact is interesting, we didn't know the history on Phil's original converter due to the Duiser diesel's questionable ownership during it's conversion. what we have to compare it to is the stock converter I put in mine after shattering my flex and tearing me modified converter that was always tighter than his 6 months ago. night and day difference between my modded converter by Dacco ( no longer in business) and non-modded original converter.
RoadRunner will further mod the converter for lower stall and install their HD lockup in this converter. I'll install this one in mine.
seems like some of the boosted 1FZ's could benefit from these mods. $250 plus shipping is small in the scope of power. just depends if yours makes power in the 1800-2300rpm range (our test we were spooling 15-20lbs of boost foot on the brake not moving in 1st, max boost is 33lbs if your trying to think back to dyno charts and HP and torque at those levels) . like I said under high HP the high end stall is still at the original 2200-2300 range of the toyota converter. just much more efficient below that point. I'd guess SC and turbo'd rigs could be more efficient with a tighter converter around town with TC unlocked.
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for any one still watching this thread. the A343F is no more. 6L80 is in and being tuned. not much in the way of pictures. still finalizing little install details to finish it up. The PCS-2650 is so much nicer than the compushift.
Zero Gravity Performance built the trans. Marks 4x4 adapter to a 100 series t-case. the 100 series t-case is about 3" shorter due to no viscous coupler. that combined to the 6L80 being 3.25" longer meant the rear drive shaft was unchanged and the front has to be extended 3.25"
Zero Gravity Performance built the trans. Marks 4x4 adapter to a 100 series t-case. the 100 series t-case is about 3" shorter due to no viscous coupler. that combined to the 6L80 being 3.25" longer meant the rear drive shaft was unchanged and the front has to be extended 3.25"
This makes me happy. Expect to see any economy perks? I’d assume… but who knows until it’s done.
