Hello All,
I have been reading this forum for a while. And have been slowly fixing up my project / daily driver 1982 280zx turbo. Currently it is consuming oil, 1/8" on the dipstick per 100miles. The car runs great, revs past 6000rpm, and has good power. It was smoking so I put 20-50 oil in and now it is not smoking. I have performed a compression test, 138psi to 145psi all cylinders. I also performed a leakdown test input 100psi drops to 75psi ~25% leak on all cylinders. I can only hear hissing through the rings on all cylinders. Valves all OK cuz I recently had the head redone. Here's my question. I found a short block on CL with flat top pistons for $150, (Datsun 280ZX rebuilt short block). I want to rebuild / refresh my bottom end. Wondering if $150 for the short block is a good deal, since all the machine work is completed. Also wondering if the E30 crank is OK for a turbo. Also wondering if I do go this route if I should swap the flat top pistons for dished pistions?
Thanks

 

#1: How many miles are on the motor?

#2: It may be your turbocharger consuming the oil. Have you checked the j-pipe / intake for oil? Did it smoke more under boost?

#3: Unless you are going to use flat top pistons instead of the turbo dished pistons, you will still have to pull the pistons from that other motor, and re-ring your turbo pistons. You could get your turbo block checked & machined professionally for $50-$150... or do it yourself for free (or the cost of a measuring caliper and honing kit).

#4: All L-Series cranks have the same measurements. The LD28 diesel crank is for strokers.

 

240060 miles. I got it last year. had the head reworked and it had a felpro head gasket so someone had been there before just no way of knowing if anything has been done to the bottom end.

J-pipe removed. intercooler installed. JWT ECU.. cobra MAF etc.
intercooling pipes are clean no oil.
I did put a new T3eo4 ebay .50 trim turbo with a full 3" exhaust. One thing I haven't done is replace the oil feed line cause I verified that it flows oil without issue. Maybe I should get a new oil feed line with a restrictor?

Any advantage of using flat top pistons over dish. I think I would prefer to stay with dished.

Yea I was originally found a shop that hot tanks the block, rebalences the crank, checks cylinder roundness, etc for $100. Just comparing the two options

Thanks

 

Addition to #2 yes it does smokes under full boost currently 10psi.

 

A good read:
https://www.zdriver.com/forums/gener...-buying-32401/

https://www.zdriver.com/forums/280zx...ts-list-36821/



Start with reading your spark plugs.