Dattsawesom

[Dattsawsum]

I have a 1975 Datsun 620 with a 1977 L20b  and parts from a 73 620 sprinkled in that I have driven for the last 30 years.

I was just about to rebuild the engine again and was wondering if there were any thoughts on how to improve the setup.

Maybe a different head or something. I figure i had it up to around 125 hp with the porting and headers and weber, But

the D port heads I've been using may need  different mode to work. 340 thousand miles on my truck so far and its part

of the family!!

[wayno]

Personally I would try to find a Z22 block out of a 1981/82 Datsun 720 or a car of the same era and build an LZ23, but you would need to find a Z22 block without any cracks in it.

What head casting do you have, the casting letter/number is between #1 and #2 plugs where the head rests on the block.

[datzenmike]

D port head???? They are all round intake and square exhaust port except the '78, and on, W58 which have round exhaust ports. The '75-'77 had U67 heads what do you have??? The head ID is along the bottom side between #1 and #2 plugs. 

 

If rebuilt it must have been bored over by now so bore it again to 87mm and use Z22 crank and pistons for basically a stroker 2.2 L20B. If you have 125 hp a 10% displacement will theoretically give you another 12 hp and this doesn't include the compression increase. New York??? good luck finding Z22 parts.