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Discussion Starter #1
I recently had my head for a SR20DET built. There were two things I noticed when I got it back from the machine shop.... First of all, they didn't change the freeze plugs. How hard would it be to change these myself? Secondly, the valve seats were not reinstalled. I used a Ferrera valve spring kit with spring locaters. Is it common not to reinstall the valve seats with this kit?

I am getting ready to send my block away as well. I have been searching forums for possibly some tips on what I should have done. Some of the suggestions were:
boring and honing with a torque plate
have the oil galleys and oil passages sandblasted and cleaned
have the crank oil holes drilled out and plugged
Are these some of the things I should definetly do to my block? Any other tips or things I should have done would be a great help.

Premium Member
3,040 Posts
First off:
If the shop did not re-install the valve seats, call them or send the head back. Properly seating the valves is critical to getting good compression and leakdown, and if they didn't grind the seats and valves to match, all that work would have been pointless. Also tell them to change out the freeze plugs, its not hard, but why do it yourself when a shop should have done it anyways for you.

As for the block:
How much money do you want to spend, and what are your goals for the engine? If money were no object and If you wanted a quick revving road race engine making not retarded amounts of power, I'd say do everything you listed above at a minimum. But in addition, lighten & knife-edge the crank then get the whole thing stress relieved or shot-peened, then get the rotating assembly micro-balanced. Aftermarket lightweight rods coupled with lightweight pistons with ceramic coatings on them (Swain Tech Coatings for engine piston coatings, race engine coatings, ceramic header coating, carbide metal coatings, thermal spray plasma coating, metalizing closures, spray welding) would make one beastly engine. Couple that with a dry-sump oiling system and you might as well pick up some extra rags, because i just shot my load.

If you were going for just a reliable engine that makes under about 450hp, then I'd suggest just o-ringing the deck of the head for better gasket sealing, then just making sure everything is blueprinted back to spec and professionally reassembled and balanced. Make sure to buy a brand new nissan front oil pump assembly and an s14 oil pickup, as well as a high-capacity oil pan (I don't recommend ebay).
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