FellowTraveler
Well-Known Member
Maybe FERM can chime in on this converter topic too.......
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Let the insanity begin! Time to Yank it.
- Thread starter WarWagon
- Start date
NVW
Well-Known Member
I have the speedo/VSSB within 1/2 mph via gps, my truck is heavy and would lug. I would often use 3rd until 45 mph to avoid lugging.
3500_6.5
Well-Known Member
Peak torque, per GM, is at 1800rpm. I always thought that was about the only good thing about the tiny turbo they put on these. For low speed/rpm towing, they always worked great.....for what they were..... That was the biggest shocker when I put the att on. I really had more low end torque with the factory tuning and stock turbo than I did with the ATT and tune. I struggled to move 12,000lb Gravity wagons around the yard with the ATT. I actually was unable to back one over a rut once. I held it to the floor until egts were up to around 1300 degrees and the truck never moved an inch. I had to put it in 4 low to get it backed over the rut. Never had a problem getting anything moving with the stock turbo. Keeping it moving or accelerating was a different story.
My tune locked the converter at 45 mph, which worked great unloaded. Pulling anything it was horrible. And it would not unlock without giving it almost full throttle. And then as soon as you let off slightly, it would lock back up. I prefer closer to 50 or higher mph the heavier I pull before having the converter lock up. And this is with 4.10s.
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My tune locked the converter at 45 mph, which worked great unloaded. Pulling anything it was horrible. And it would not unlock without giving it almost full throttle. And then as soon as you let off slightly, it would lock back up. I prefer closer to 50 or higher mph the heavier I pull before having the converter lock up. And this is with 4.10s.
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FellowTraveler
Well-Known Member
My Burb runs great w/HX40w 18 cm2 I was pleasantly surprised how it spools enhanced drive-ability across the rpm range too
Good point about "unloaded" as I never gave it a second thought. My trans tune is a little on the lugging side as it will smoke some before unlocking as you ease into the throttle on a hill. IMO it's just about a perfect tune letting me play on the lugging side slightly and just a touch more throttle unlocks it, rev up, and smoke gone.
Absolutely the loss of the bottom RPM TQ/HP is why I stalled it. This trade off is worth it to me as I need grade climbing power above 2200 RPM at speed more than low speed maneuvering. Now I have both. But, I can't eat this cake as 4X4 is needed for safety in reverse with full 'brake stall' power. I like the 'biggest' turbo freight train pulling all the way past redline vs. the power fall off of the midrange HX40II I tried. Again a trade off although the lower spool RPM wasn't that apparent as it didn't light till 2K RPM same as the ATT from a dig. Rolling you could notice the difference between them.
I use 2200 RPM as this is the peak power and MPH I get with the GM3 turbo towing. It may have the TQ falling off faster at 2200 RPM than 1800 - 2200 RPM. Not bad for SOTP feel.
Absolutely the loss of the bottom RPM TQ/HP is why I stalled it. This trade off is worth it to me as I need grade climbing power above 2200 RPM at speed more than low speed maneuvering. Now I have both. But, I can't eat this cake as 4X4 is needed for safety in reverse with full 'brake stall' power. I like the 'biggest' turbo freight train pulling all the way past redline vs. the power fall off of the midrange HX40II I tried. Again a trade off although the lower spool RPM wasn't that apparent as it didn't light till 2K RPM same as the ATT from a dig. Rolling you could notice the difference between them.
I use 2200 RPM as this is the peak power and MPH I get with the GM3 turbo towing. It may have the TQ falling off faster at 2200 RPM than 1800 - 2200 RPM. Not bad for SOTP feel.
Additional install instructions: Use Blue locktight on the converter bolts to keep them from backing out. Had one back out on me.
94DieselSub
Member
@3500_6.5,
Just wanted to thank you for an excellent posting in this thread!
I frequent this & another (Place) 6.5 friendly Forum. The amount of ego-centric bantering noise regularly strewn as authoritative knowledge can really become discourage at times.
Unbiased real world results are gold for the new / uninitiated members of these Forums!
Keep up the good work!
Just wanted to thank you for an excellent posting in this thread!
I frequent this & another (Place) 6.5 friendly Forum. The amount of ego-centric bantering noise regularly strewn as authoritative knowledge can really become discourage at times.
Unbiased real world results are gold for the new / uninitiated members of these Forums!
Keep up the good work!
Nice flash to ~2000 RPM from a dig. Of course 2K is where the ATT comes to life. A bigger pump would flash more RPM best seen after the shift around 70 MPH. As it is boost is around 11 PSI when it is capable of 14-18 - just not enough fuel.
I mean I pass emissions without screw adjustments and the fuel screw is buried now...
I know this is an old post, but I'm sitting here with my jaw on my desk...awesome, simply awesome!
Will L.
Well-Known Member
Oh? I was joking, but cool! Anything you want to tell about it? like Jr or big boy? anti smoke stack attenuation device? gong stock pressures?, etc...