L18 Pistons/ L28 pistons

[stedy sss]

Can someone tell me if I can use L28 pistons in a L18. I no there STD 86mm that's OK cos the L18 is getting bored out. But is everything else compatible?

Just having trouble finding the right dished and over sized piston. If the L28 piston works, it give me a few more options.

Cheers

[torqued]

http://www.nzdatsun.com/forums/viewtopi ... l18+piston" onclick="window.open(this.href);return false;

[hsepwr]

This guy on ozdat has done it read his thread


http://ozdat.com/forum/viewtopic.php?f=28&t=30320" onclick="window.open(this.href);return false;

[stedy sss]

That's all good cheers guys

[nzdatman]

I was wondering the same thing but for L20B. Seems valve clearance can be pretty tight depending on the cam you use. Nothing a little bit of fly cutting can't fix though

[68p510sss]

My spare race motor is a L20B with L28 pistons. I have used this with a cam that gives over 1/2 inch of valve lift with no clearance problems. I am sure the same would work in a L18.

Good luck Andrew

[nzdatman]

Did you use the dished L28 pistons or the flat top ones?

[68p510sss]

These where dished pistons, however I have used that cam with flat top pistons. There are so many variables when it comes to valve to piston clearance. ie how much the head is planned the valve seat level the camshaft profile, the stroke and conrod length. The other critical feature sometimes overlooked is if the chain is loose and relying on the tensioner. Under deceleration the timing can effectively moves and then causes problems. The 86 mm L28 piston has the same pin height and the increased bore itself has no effect on clearances.

Personally I like to carefully turn the motor over with Plasticine and check clearance that way. I also do that at several valve timing settings to know how much we can safely vary timing when on the dyno