Eagle_Adam Posted May 6, 2013 Report Share Posted May 6, 2013 Lolz, now that ive got you here. I picked up a half built motor to assemble and it seems the rods are too short... A little background: L20 block Zcar flat top pistons thats all you need to know :P What rods do i need to get the pistons to work in an L20 block? The current ones, from an unknown source are about 3/4 inch too short Link to comment
Eagle_Adam Posted May 6, 2013 Author Report Share Posted May 6, 2013 yes, guess that would help huh? Link to comment
Laecaon Posted May 6, 2013 Report Share Posted May 6, 2013 L20 rods. Pistons should be same height. Link to comment
Eagle_Adam Posted May 6, 2013 Author Report Share Posted May 6, 2013 then where the fuck did the guy i bought the motor from get shorter rods? Link to comment
RedBanner Posted May 6, 2013 Report Share Posted May 6, 2013 Well. Maybe the rods that where on the piston are l28 ones. Link to comment
Eagle_Adam Posted May 6, 2013 Author Report Share Posted May 6, 2013 they may be..... but thats not what i was told and i never double checked so its my fault :angel: but its delaying the build for my girls motor :mad: Link to comment
datsunaholic Posted May 6, 2013 Report Share Posted May 6, 2013 L20 or L20B? L20 engines have an oddball pin height- 40.1mm, vs everything else at 38.1mm But the L20 is tiny- 78mm bore, 69.7mm stroke. Can't use normal Z-car pistons in a L20 due to that. L20B, otoh, uses the normal 38.1mm pin height that all US-marked L-series (4 AND 6 cyl) use, so if you're actually talking a L20B, then stock-pin height L28 pistons will fit. So, maybe you got L20 (or L20A) rods? I saw somewhere they're the same length as a L16 rod (133.9 mm center-center). L20B are 145.9mm center-center. That's almost half-inch difference though. EDIT- late L20a rods apparently are 135mm... so it gets even weirder. 1 Link to comment
Laecaon Posted May 6, 2013 Report Share Posted May 6, 2013 l28 rods are almost 16mm shorter than l20 ones. I would say that's your problem. 1 Link to comment
EricJB Posted May 6, 2013 Report Share Posted May 6, 2013 Are you sure the pin height is right on the piston? Should be 1.500 from the top of the piston to the center of the pin. Rod should be 5.75 center to center. Link to comment
Laecaon Posted May 6, 2013 Report Share Posted May 6, 2013 L20 vs l20b. Bleh, l20 parts are rare enough to just about never consider them. 1 Link to comment
Eagle_Adam Posted May 6, 2013 Author Report Share Posted May 6, 2013 yes, its an L20B, i found a spare set of L20B pistons and rods so ill drop em off with my machinist so he can continue the assembly! Thanks guys! Link to comment
RedBanner Posted May 6, 2013 Report Share Posted May 6, 2013 If that doesnt fix it, you need to measure the stroke. Link to comment
RedBanner Posted May 6, 2013 Report Share Posted May 6, 2013 Actually you should do that before you even pull it back apart. Link to comment
Eagle_Adam Posted May 6, 2013 Author Report Share Posted May 6, 2013 just left the machinist, L20B rods are correct. The PO must never have had them dismount the L28 rods and mount the L20B rods Link to comment
Laecaon Posted May 7, 2013 Report Share Posted May 7, 2013 Woot, 5 datsun points for Banner and I! Link to comment
banzai510(hainz) Posted May 7, 2013 Report Share Posted May 7, 2013 I would not use flattops in a L20 myself. unless you got 95plus octane Link to comment
Laecaon Posted May 7, 2013 Report Share Posted May 7, 2013 I would not use flattops in a L20 myself. unless you got 95plus octane Too late, motor is assembled. Link to comment
Eagle_Adam Posted May 7, 2013 Author Report Share Posted May 7, 2013 the new heart for the goon!!!!!!! this one can be locked!! Link to comment
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