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  #11  
Old 12-21-2020, 05:09 AM
jetfiremuck jetfiremuck is offline
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Follow up. I adjusted the fuel screw again and eliminated the concern I had when the throtttle was snapped idle to high rpm the engine rpm hung before idling back down. Idle speed adjusted after.

Re boost drop off. I removed the boost diaphram and checked the boost pin rod in the pump for freedom which connects to the boost pin. It was ok. I turned the star wheel 1/4 turn in. I set the boost pin to max travel removing the plastic spacer. Refit the boost pin with the ramp on the most agressive side contacting the pin.

Road tested and the boost now holds when the trans shifts and is much more responsive once the turbo kickes in.. At 55 steady Im running 7lbs boost. The truck is heavy so acceleration in top gear converter locked is slow
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  #12  
Old 12-21-2020, 04:39 PM
v8volvo v8volvo is offline
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Sounds like you got a lot of improvement out of it, that is good. The way you describe it working now sounds right, if it is holding boost during gear changes then it's working like it should.

What kind of axle gearing does it truck have? I am not surprised it's pretty slow accelerating at highway speeds, those are tall and square trucks too. The D24T engine does not mind revving 3000 rpm or more so putting shorter gears in it might help it run better on the highway. Pushing that kind of rig I think I would want the converter to lock up no earlier than 60 mph or so. It does sap the punch once that lockup occurs.
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  #13  
Old 12-31-2020, 07:09 AM
jetfiremuck jetfiremuck is offline
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Agree with the discovery being a brick. The rpm at 70mph flat out is 2500rpm. Not expecting much better as the weight coupled with 265/70/18 tires and 3.54-1 gear ratio leaves very little when the converter is locked. it locks up about 60mph. Im using the volvo 760 valve body.
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  #14  
Old 12-31-2020, 07:32 AM
v8volvo v8volvo is offline
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You might do even better if you were able to regear the axles (though I know that is a lot of work and expense). That is pretty tall gearing especially with the bigger tires and size/weight of the truck.

To give you an idea, in the Volvo 7 series TD cars with factory automatic, the tire size is 195/60R15 and the rear end is a 3.91. The torque converter lockup occurs at about 45mph and at 70mph I think the revs are over 3000. So, much shorter gearing and smaller tire circumference, plus of course it's a much lighter and smaller vehicle, and only driving one pair of tires. IIRC the Land Rover transfer case runs 4x4 full time with a center diff right? So more driveline friction and inertia too.

Seems like in your setup a set of 4.30 or 4.56 gears in the axles might be about ideal? If such are available?

Or just run it in low range all the time....

Would be great to see some pictures or video of your installation sometime, I would like to try one of these builds myself someday.
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