ive been researching to find out what would influence the bearing clearances as im debating if im going to go fully built or not. Ive located some ACL bearings but from reading their site, they CAN come in STD, .025, and .25 ... i think the ACL bearings i found are in std though.
im taking my crank out to install a jun/tomei crank collar. if im keeping stock, i planned on reusing the factory bearings ... but as every one and their grandmother would say this is a the best time to build things im looking at the eagle rods and wiseco .020 pistons
i know that carl and darius have gone fully built ...
can anyone shed some light ???
main & rod bearings - sizing ??
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Darius
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Re: main & rod bearings - sizing ?? (minivan_don)
You need to have your crank journals measured to the nearest .001mm with an outside micrometer. Then you need to measure the large end of the rods with the caps torqued down to the nearest .001mm with an inside micrometer. Compare the difference to that of the stock clearances including the oil clearance and buy bearing thicknesses accordingly. Odds are that you will only need STD sized bearings if your crank journals are not being machined anymore than just micropolishing (i.e. if they are out of round or tapered front to back).
YOU NEED TO VERIFY THESE MEASUREMENTS SO YOU CAN SLEEP AT NIGHT AND NOT WORRY ABOUT YOUR MOTOR EXPLODING ON YOU BECAUSE YOU CUT CORNERS AND MADE ASSUMPTIONS.
If you are going with larger pistons, you need to have your block bored and honed. You also need to consider compression ratio and all that fun stuff. Then, once you get your bearings and rod bolts, have everything balanced. Pistons should all be within 1.0 gram, which is most likely with any good forged piston manufacturer.
I would also find an engine building handbook of some kind for general procedural pointers and helpful tools like a ring filer and ring expander. The typical measurements may be out of date, but the ideas are still the same as they were 15 years ago.
YOU NEED TO VERIFY THESE MEASUREMENTS SO YOU CAN SLEEP AT NIGHT AND NOT WORRY ABOUT YOUR MOTOR EXPLODING ON YOU BECAUSE YOU CUT CORNERS AND MADE ASSUMPTIONS.
If you are going with larger pistons, you need to have your block bored and honed. You also need to consider compression ratio and all that fun stuff. Then, once you get your bearings and rod bolts, have everything balanced. Pistons should all be within 1.0 gram, which is most likely with any good forged piston manufacturer.
I would also find an engine building handbook of some kind for general procedural pointers and helpful tools like a ring filer and ring expander. The typical measurements may be out of date, but the ideas are still the same as they were 15 years ago.
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minivan_don
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Re: main & rod bearings - sizing ?? (Darius)
thanks for the input!
yes, im am very aware of the needed boring/honing of the cylenders to install the wiseco pistons. i planned on getting everything balanced to ensure accuracy.
as for the yielded compression ratio ... wiseco claims it to be 8-8.4:1 but thats on either the .020 or 0.040 over bore. i think it will be closer to 8.4 as its the smaller of the boring.
http://www.wiseco.com/PDFs/Cat...n.pdf
yes, im am very aware of the needed boring/honing of the cylenders to install the wiseco pistons. i planned on getting everything balanced to ensure accuracy.
as for the yielded compression ratio ... wiseco claims it to be 8-8.4:1 but thats on either the .020 or 0.040 over bore. i think it will be closer to 8.4 as its the smaller of the boring.
http://www.wiseco.com/PDFs/Cat...n.pdf
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minivan_don
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Re: (Carl H)
oh ... and getting the block/head resurfaced (and using a stock hg) would probably yield about 8.4-8.5:1 compression
where did you get your bearings from carl ??
where did you get your bearings from carl ??
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FAST-DATSUN
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