Installing HD2 in 4l80, need help with shift firmness settings
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Installing HD2 in 4l80, need help with shift firmness settings
Hi, Im in the process of installing the hd2 shift kit in my 2500hd. I have a circle-d 258mm 3000rpm stall converter. They list 4 levels of shift firmness to choose from when drilling out the holes(softer, average, firm, and race). Would you recomend doing them all the same(holes a b and c), and would you do the firm setting since I have the 3000rpm stall? I like a firm shift at wot, but dont want neck snapping shifts at part throttle. They say in the instructions that average works great for hd trucks, but I was thinking since i have a 3000rpm stall I could get away with a firmer setting. The converter softened up the shifts quite a bit.
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It really depends on the converter you are using. I went with the average settings and my 1-2 shift is just plain wicked and thats even with up to 60 psi being pulled during the shift in the shift pressure tables because otherwise it was going to be a drive shaft snapping jolt. I only tried it twice like that and both times the truck turned to jello and it tried to kick itself sideways it hit so damn hard. Now to answer your question I do have a very very very tight converter in mine. It doesn't soak up the shift firmness at all. Its the same converter the 6.5 diesels used and I've managed to stall it up to 1500. That being said my 2-3 shift is firm but nothing like the 1-2 and I've actually added a lot of pressure to the 2-3 to make it firmer but its still not quite all there. My transmission was used, high miles, with a lot of material in the pan so the direct clutch could very well be weak but it in no way slips either. 3-4 shift is very similar to the 1-2 shift. I've had to pull pressure there as well to make it livable. I say try the average settings. Its not that far back in there to change, just the tranny fluid dripping in your eyes that sucks.
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i would go average for the 1-2 and firm for the rest... i did firm on all and my 1-2 is pretty harsh.... barks tires 90% of time and clunks at part throttle.. i like it at full throttle but its a lil too hard at part throttle but its definetely driveable...
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i also went the firmest with the springs too theres one spot where you put both springs or just the inner or just the outer.. i dont remember what is what but i went with firmest and i wouldnt do the that again!!!
ALSO built408 knows what he is talking about... so maybe you should listen to him... i think id try average across the board....
ALSO built408 knows what he is talking about... so maybe you should listen to him... i think id try average across the board....
#7
if you have a loose converter it wont be nearly as harsh because the converter will soften the hit.
so if you have a 4000 stall id say drill the big holes, if its a stock converter go with the smaller holes.
so if you have a 4000 stall id say drill the big holes, if its a stock converter go with the smaller holes.
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