1969 SE5 Alfa V6 conversion: My LSD trip.

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1969 SE5 Alfa V6 conversion: My LSD trip.

Post by fightingtorque » Mon Oct 30, 2017 10:06 am

Thanks Jim. Looking at that manual it seems the "standard" is normally 0.007" (0.18mm), which seems reasonable, and then elsewhere in the manual it shows how to interpret the contact patch found using engineers' blue.
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1969 SE5 Alfa V6 conversion: My LSD trip.

Post by GavinR » Fri Nov 03, 2017 2:38 pm


The preload on the differential case bearings is achieved by fitting shims under the bearings to give the required preload
(I think the IRS units achieve preload by attaching the output shafts to the diff casing so don't need these shims)

Once you have the correct preload, you can then swap shims side to side to adjust the backlash, keeping the same total shims - make sure the pinion is at the correct depth first though

It usually takes a while and a few attempts to get it right - you also need a decent puller / press to get the bearings off and on!
I've seen 8-10 thou backlash in other manuals so it doesn't need to be exactly 7 thou


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1969 SE5 Alfa V6 conversion: My LSD trip.

Post by rossnzwpi » Mon Dec 18, 2017 12:14 am

Hi, just a wee thought on that 3.0 Busso V6. The 2.5 is a sweet high-revving engine with sufficient power and torque for most people's (maybe yours???) needs. The 3.0 was used in various cars and, if I remember correctly, in the Alfa 166 it was re-tuned to favour smooth, lower rev lugging so isn't as sporty. What I'm saying is I think you have a great engine with a 2.5 Alfa 156!

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