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electronic drawing board essentially

Would anyone like to share pick-up designs, in particular the external?

I posted some pics of a sump i had done recently but cant remeber where i posted them, so here's some of the actual external pickup

smup009fh4.th.jpgsmup007ia0.th.jpg

cool! hey so with these fancy uber strong billet main girdles, how does one adjust the endfloat of the crank if they are all tied in with countersunk bolts?

Someone has had there thinking cap on, I wondered how long it would take for that to pop up.

Rob

Im not an engine builder but i have discussed this with one and like adriano says its adjusted via the thrust bearing thickness or width of the cap.

The cradle has zero effect on it other than width/alignment of the middle cap. So it boils down to how good the machinist is.

Does that sound about right to you rob?

read the nisan workshop manual?

yes. if the girdle is perfectly aligned, no probs if the crank is at factory size and not an auto, and every block is differant, a thou here a thou there... i can see this being an issue. unless you supply a full range of NISSAN main bearings.

you could supply instructions on how to use an oil stone if it goes in to tight. but what if it goes in at 5 or 6 thou?

im just saying that there needs to be a way that the girdle can be adjusted.

read the nisan workshop manual?

yes. if the girdle is perfectly aligned, no probs if the crank is at factory size and not an auto, and every block is differant, a thou here a thou there... i can see this being an issue. unless you supply a full range of NISSAN main bearings.

you could supply instructions on how to use an oil stone if it goes in to tight. but what if it goes in at 5 or 6 thou?

im just saying that there needs to be a way that the girdle can be adjusted.

You only need to "adjust" it to get the upper and lower thrust faces level with each other, not to take up extra clearance by using one thrust face of the upper bearing and the opposite thrust face of the lower. If it has too much clearance you need o/s thrust bearings. If the caps/girdle etc are set up in the right place and countersunk fasteners used it shouldn't be any more of a problem than in many other engines where the caps are doweled to the block, VQ35 for instance.

BTW, to answer a question a page back about the lower bellhousing bolt holes, I have sumps welded up and re-drill the bottom bolt holes. It's a bit fiddly but not a massive problem. I'll take some photos of the next one.

The cradle has zero effect on it other than width/alignment of the middle cap. So it boils down to how good the machinist is.

So when the block is line bored you have to also machine the sides of the center cap on the cradle to exactly match the sides of the center main in the block?

Rob

So when the block is line bored you have to also machine the sides of the center cap on the cradle to exactly match the sides of the center main in the block?

Rob

The sides are machined to size on the cnc and then the radius' are cut on the line borer.

The sides are machined to size on the cnc and then the radius' are cut on the line borer.

Ok, so how do you know every block is going to have its center main faces in exactly the same place relative to the outer perimiter rail bolt holes you are using to spigot the cradle?

Rob

Ok, so how do you know every block is going to have its center main faces in exactly the same place relative to the outer perimiter rail bolt holes you are using to spigot the cradle?

Rob

Would there be more than ~20thou variations between the blocks though? There's 20thou clearance around all the countersunk holes, so there is room to move in that.

How do you go about that? Urs would be similar with the 4 bolt mains ur using.

an exhange program may be a solution?

yeh that's something i'm considering. Provide a bottom end with atleast bearings in and clearances set.

yeah. last thing you need is a bloke 100000kms away slaging your shit after hes paid good money and the f**ker locks up when its all tensioned down..

shane.. so your countersunk holes are oval? what about when its tightened? wont it centre itself being a taper?

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