Long rod 3liter,L28d block

[Guest Anonymous]

Was thinking about this the other day and was wondering what mods are necessary for using a L28d block with a P90a or N42 head.The reason is the extra 20mm of deck height.Here's the motor combo

Stroke L28d crank=83mm

Rod Z20e=152.5mm

Piston VG30 1mm overbore for 88mm, 1cc dish 31.75mm pin height

Block L28d =227.45mm deck height

S/2+R+P=225.75 for 1.7mm below deck height at TDC

152.5/83 for a 1.83 rod to stroke ratio and Radius squared x 3.14 X stroke for 3027cc

The compression would be around 8.0:1 with a P90A's 53.6cc chamber or 9.0:1 with the N42's 44.6cc chamber.

If anyone knows the mods for using this block or you see a wrong dimension listed or bad math please let me know.

Thanks

[Kennysgreen280zt]

someone on this forum has done it , you use a L20 front cover and timeing chain i think , you should search the past posts. sounds like a good idea if the D block will take an 88mm bore.

~Kenny

[DAW]

That works out pretty well, what you've described. I like to work just from the crankpin, so, stock LD28 is a 140mm rod + 46.5mm compression ht = 186.5. Using Z20E rod = 152.4mm + 31.75 compression ht =184.15, or just over 2mm below deck. 84.5 to 88 is a big (3.5mm = .150") overbore, even on a diesel block. Also, watch the VG30E pistons, as they are rather narrow on the underside between bosses where the rod has to go. I have yet to check out a piston from a CA 20E (84.5mm), and I don't know what the compression ht is.

How about an L28E piston, 86mm (0.60" overbore), 38.1mm compression ht, (186.5 - 38.1 = 148.4, and that's the rod you need. Z22E = 148.6.) Use flat-top L28s and an N42/47 head and it's a nice long-rod engine with over 10:1 compression.

If you want more, then consider European flat-top L28 pistons in + 1mm (P8617 = 87mm) with the small pop-ups, combined with a P79 (or P90 turbo) head (both of which have the closed chambers), and you've got an engine with a high c.r., and a long rod/stroke.

DAW