M70B54 project

[exalted]

Using some dread necromancy I'd thought to ask about those crank bolt problems.

What would the proper length be M73 bolt + 13mm? Something else? Should one use a spacer?

About the only step that is left in my M73 hybrid is that damn bolt.

IMG_20230723_151947.jpg

[merlin840]

i could be wrong but i believe the impeller of the M73 pump fits deeper into the block only by a millimeter or so but it fouled on my CSI block when i fitted it I was given a M73 water pump during our covid lockdown and i had to modify it to fit i was told that the M70 one had been superseded to this model which fitted both probably bullshit but during the lockdown i had no way of returning the pump

[sl350]

[QUOTE=exalted;30896220]Kauhean nekromantian perusteella ajattelin kysyä noista kampipulttiongelmista.

Mikä olisi oikea pituus M73 pultti + 13mm? Jotain muuta? Pitäisikö käyttää välikappaletta?

Ainoa askel, joka M73-hybridistäni on jäljellä, on se pirun pultti.

IMG_20230723_151947.jpg[/LAINATA]

There is a hybrid m70/73 project going on here. I have read through quite a few replacements, many have used the m73 bolt. I've measured the thread part of the original m70 bolt is about 24mm, if you use an m73 bolt, the thread part used to tighten the bolt is only about 10mm, I'm not going to use an m73 bolt, the bolt has to be longer. The alternative has become the N47 bolt, which is 85.5 mm long, I plan to use it with the m70 washer. The oem number of the bolt is 1123 7 790 922

[exalted]

There is a hybrid m70/73 project going on here. I have read through quite a few replacements, many have used the m73 bolt. I've measured the thread part of the original m70 bolt is about 24mm, if you use an m73 bolt, the thread part used to tighten the bolt is only about 10mm, I'm not going to use an m73 bolt, the bolt has to be longer. The alternative has become the N47 bolt, which is 85.5 mm long, I plan to use it with the m70 washer. The oem number of the bolt is 1123 7 790 922

Thanks hadn't gotten to actually measuring my old ones, does the N47 works without any fiddling with the bolt? Because 10mm sounds a bit to little for me.

Washer mounted in the original fashion of the M70?

Project hasn't really progressed on that front too busy with welding some turbo headers and work.

[sl350]

Attached is a picture of m70 without washer, m73 and n47 bolts. I installed a n47 bolt without a washer. I turned the edge of the bolt to the same size as the washer of the m70 bolt, if I ever have to replace the water pump, there is no need to remove the bolt. It was very easy to tighten to the guideline values.IMG_2746.JPG
​IMG_2756.JPGIMG_2757.JPG

[8eights]

Do the "diff" swap, it's worth it.

Considering the stock ratio is 3:64 going to 3:91 isn't that radical. Swapped diffs years ago & I still cruise effortlessly up/down the "405" @ 80mph here in Southern California during the hours from 4am to 6am....weekends only!��

A chipped Trans module helps there as well.

Sent from my SM-N960U using Tapatalk

[TedBobo]

A chipped Trans module helps there as well.

Sent from my SM-N960U using Tapatalk

Yep, I have the Dinan transmission chip.

[exalted]

Attached is a picture of m70 without washer, m73 and n47 bolts. I installed a n47 bolt without a washer. I turned the edge of the bolt to the same size as the washer of the m70 bolt, if I ever have to replace the water pump, there is no need to remove the bolt. It was very easy to tighten to the guideline values.IMG_2746.JPG
​IMG_2756.JPGIMG_2757.JPG

Thanks think I'll do the same after the holidays, just have to order the bolt from BMW.