I'm having a difficult time determining the best reference point on a 4l60e transmission to measure the drive-line angle from. Can I use the top of the casing by the gear select electrical plug or is there a better spot? I had to hack the old 4.3 v6 mount out due to the installation of the 5.7 v8 engine. A new mount will be fabricated and installed about 14 inches back from where the original one was. I did lower the rear end as well which used tapered blocks in the kit. I wonder now should I have measured the height of the old trans mount before cutting it up and hammering it out of its location. It's just twisted / rusted scrap now.
Your intake should be level... If not you may have problems with fuel (Carbureted).... then you'll have your angle for your transmission.... what ever that angle is, Usually around 2 - 2.5 degrees then you can set the pinion angle at the rear yolk.
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I set the frame level front to back and then set a level on carb base and get that level. I use 3-4* down which can be taken off the output shaft of the trany which is where you are working at. You also have to have the diff yoke pointing up the same angle.
even with injection you might want to stay away fron excessive engine angles considering the pooling of oil trying to drain back to the pan
in some motors that oil draining back can really add to the lube the cam gets
in my stock 383 mopar , the block casting was a little different at the very front of the block due to the way it was designed
this seemed to affect the oil splashing on the cam (I think) as the front two lobes looked a little more worn than the rest
an excessive angle down towards the rear would have made this even worse
Got the angle all sorted out. The top of the air intake agreed with the rocker covers and also with the drive shaft slip yoke when held entered. All match the pinion angle.
The new transmission mount was fabricated and installed and is removable. It ended up about 18 inches back from the original location. Next step is to have the driveshaft shortened to fit.
Simple.... cut or have your tube cut directly beside the weld at either end (just the tube though) it's only about 1/8 thick don't cut through the plug inside of the tube.... slide the plug out... cut your tube too the length you need ... put your plug back in , make sure you have the eyes lined up with the other end... then weld it up When I did mine I found a drive shaft that I only needed to shorten it 2 inches... and I cut the end that didn't have the weight welded on it. Other option is to have one made and balanced.
Remember to measure from the center of the eye to the center of the other eye at the opposite end. and allow for the the slip in the yoke when the suspension travels.
-- Edited by 30-S6 on Sunday 10th of June 2018 05:55:07 PM
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The best way to get on your feet is to get off your ass.
I cut off at the rear end, shorten the tube to length, tap the end back in (whether it's from the same shaft or from another shaft so it matches the rear being used) then, before tack welding I install the shaft in the car, verify the length is correct, then I set up a dial indicator on the tube, as close as possible to the area to be welded, and slowly spin the shaft, adjusting the end as needed with the tap of a hammer, until there is virtually no run-out. I then tack in four spots, remove and fully weld.
If your tube hasn't been cut on a lathe (mine was not and I doubt many home mechanics get them cut on a lathe), just tapping the end back into the tube may not give you an acceptable, wobble free shaft but truing it before the weld (dial indicator) worked great for me as I didn't even need to get it balanced.
Trust me on this ... tap it in then set up an indicator and you might be surprised how far out you actually are (dial indicators can be purchased for next to nothing from Princess, along with a magnetic base).
I should add, I Mig welded mine (just noticed your comment about Tig).
-- Edited by Pete Moss on Monday 11th of June 2018 07:28:19 AM
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