My 80e swap has begun

lol damm,bet that felt ugly,but good to hear ,ill get that 4200 stall pretty soon,if i can before 26th.....

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Originally Posted by farmtruc

truck is all done! the 6speed helps those big trucks along great, but put it in a small truck and it's even better! no converter really required, however, it needs one at idle with such a big cam.
a converter would make it shine even more through each shift.
this aint the first 6speed i realize, we've all tuned them and drove in them, however, in a regcab, it's awesome!

i'll do a complete write up on it soon, not too bad at all!!!

one bad thing about zach's swap! damn! the driveshaft broke in the center. it reached it's critical speed and with such a small diameter, 4.56 gears and 2 more gears, the shaft is spinning too fast to stay together.
i'm thinking a 4" alumin will be just right.

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man truck sounds like a beast with that setup. why an aluminum ds, wouldnt a steel ds be stronger?

factors that play into critical speed are , diameter, length, material, trans gear ratio, rearend ratio.
Aluminum has about a 20% higher critical speed than steel, so they say. Critical speed is the rpm at which a driveshaft can spin before it begins to wobble in the middle and then break, which happened to this one.
It had nothing to do with power, it had to do with the shaft spinning faster due to the 6speed auto's gear reduction (engine spins slower, so something has to spin faster).

Aluminum without a doubt is weaker than steel, however, this truck has 4.56 gears, a 6speed auto and the engine turns high rpm, and with aluminum having a higher cs, that's one reason why an alum was chosen. It needs a shaft that will take the rpms and not break.
If there was a 5" diameter shaft we'd get that one!

Cool i get it. Not to thread jack or anything, but in my case would a 3" steel ds be ok in a 3700lbs truck, 28" tire, 4.11 gears, and the gearing of the 60e? or would the aluminum be a better option?

nice...cant wait to get on the bitch haha.....

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Originally Posted by lechez71

Cool i get it. Not to thread jack or anything, but in my case would a 3" steel ds be ok in a 3700lbs truck, 28" tire, 4.11 gears, and the gearing of the 60e? or would the aluminum be a better option?

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just have to try and find out, some stock trucks use stock shafts and get away with it, some make it , some don't

just a little update, they recommended a 5" diameter shaft, damn! you have the thickest shaft we've ever handled :)

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Originally Posted by farmtruc

just a little update, they recommended a 5" diameter shaft, damn! you have the thickest shaft we've ever handled :)

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damm no shlt ..so they were able to make a 5' ...badass post a pic lol

is thrash building the ds?

maybe

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Originally Posted by farmtruc

just a little update, they recommended a 5" diameter shaft, damn! you have the thickest shaft we've ever handled :)

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thats what she said

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Originally Posted by farmtruc

just have to try and find out, some stock trucks use stock shafts and get away with it, some make it , some don't

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he's right...mine didnt make it in my '05 avalanche.

im gonna give it shot, my truck weights about half of an avalanche. i think it will hold up for now.

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Originally Posted by lechez71

im gonna give it shot, my truck weights about half of an avalanche. i think it will hold up for now.

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remember, at your power level, it's not about weight or hp, it's about how fast you turn that shaft and it's critical speed.

So acording to your theory, if someone goes from 3.23 gears, 26" tires 1:1 @ 6800rpm, to 5.33 gears and the same tires...everything else remain the same, he will be snapping the driveshaft ??????

Or is just the longer DS as in AVEs, CC, EC tend do to more flexing at higher rpm?

Have you made some stats of how many RCSB have this problem, compare to the others?

One thing is certain, the faster u spin a driveshaft the more prone it is to breaking

Gears tires overdrive all affect critical speed.

Some break and some don't.

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Originally Posted by farmtruc

One thing is certain, the faster u spin a driveshaft the more prone it is to breaking

Gears tires overdrive all affect critical speed.

Some break and some don't.

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if u aint breaking,u aint going fast enough ...

yo you watching the fights tonight?Silva!

Stands to reason. With 4.88 gears and running the 1/8th mile a lesser driveshaft will more likely survive longer than if it were taken to a 1/4 mile track and turned higher RPM. I've always wanted to put a high speed camera under a truck with a 4' or longer driveshaft running large number gears and pushing real power. I bet that driveshaft grows 6" larger in diameter by the time they hit the end of the quarter.

looks good zach...
I'm looking for more information on a 6 speed swap for my NNBS...
I've follewed Niffs thread on pt, I would love a write up about zachs truck..

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Originally Posted by RedHeartbeat

Stands to reason. With 4.88 gears and running the 1/8th mile a lesser driveshaft will more likely survive longer than if it were taken to a 1/4 mile track and turned higher RPM. I've always wanted to put a high speed camera under a truck with a 4' or longer driveshaft running large number gears and pushing real power. I bet that driveshaft grows 6" larger in diameter by the time they hit the end of the quarter.

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Probably looks a lot like a jump rope.