Distraction240z Posted December 31, 2022 Share Posted December 31, 2022 (edited) Hello everyone I have a 1971 240z that is pretty original, the engine is getting tired and I am looking to rebuild a L28E form a 1983 280zx that I have found locally for $1500 Canadian. I am looking for your opinion on the simplest rebuild with the most bang for my buck that will. 1) Run on 87 octane fuel. 2) Still use my original SU Carb. 3) Be easy and reliable, not looking for big power anything over 150 at the wheels is great. 4) Cost no more than $6000 of my Canadian pebbles. I think the safe option for a slightly better rebuild than stock will be the use of the Z22S Pistons and L24 Con Rod. The compression height of the Z22S pistons is 35.5mm with a bore of 88mm. The Datsun L series engine have a block deck height of 207.85mm. Or Nissan FJ20 140mm Connecting rods, and Xr500 89mm pistons. About 1500$ for connecting rods, pistons, rings, everything but bearings. From my research there are two small problems. An extra 1.25mm in deck height (209=(79/2)+29.5+140) and the small end width of the Honda piston 20mm vs the 20.5mm of the FJ20 con rod. I think I can solve the piston issue with a thicker head gasket or taking some material off of the top of the pistons, which one is better? I also don’t think it would be a big problem to remove 0.5mm from the con rod small end width to fit the Honda Piston. If you haven’t guessed I want to run FJ20 Con rods and XR500 pistons, but am concerned with over boring to 89mm. If you have some old school fixes, tips, advice or if my information is wrong, please share with the class. measurements are mm FJ20 Con Rod L24 Con Rod Datsun Spirit Con Rod Center to Center 140 133 139.5 Big End Dia 53 53 53 Small End Dia 21 or 22 21 21 Big End Width 26.8 26.8 26.8 Small End Width 20.5 23.9 23.9 Price USD Per Cylinder EST 58.17 111.33 204.17 XL500 Z22S Datsun Spirit Piston Bore 89 88 89 Compression Height 29.5 35.5 29 Wrist Pin Dia 21 21 21 Small End Width 20 Standard Standard L24 Piston Height 66 Price USD Per Cylinder EST 80.45 100 237.5 Rod to Stroke Ratio 1.772151899 1.683544304 1.765822785 Compression Height 209 208 208 Price Per Cylinder EST 138.62 211.33 441.67 Edited December 31, 2022 by Distraction240z Quote Link to comment Share on other sites More sharing options...
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.