heads???

[brianglawson]

ok i was wondering about if it was possible to mount a jdm datun head to a stateside motor like the twin cam 4 valve head

or maybe the crossflow head found on the rally cars

also where would i source one??

[HS30-H]

Hi Brian,

Dream on.

The head of the S20 engine ( found on the PGC10, KPGC10 and KPGC110 Skyline GT-R's, and the PS30 and PS30-SB Fairlady Z 432 and 432-R ) will NOT fit any L-series sixes.

Apart from the obvious issues of water and oil passages not coming even close to lining up, you have the problem of turning the oil pump and distributor drive from the L-series crank to fit the S20 head's arrangement. Also the problem of adapting a single OHC chain drive to a double cam arrangement with a completely different chain tensioning system and length. You'd be looking at different pistons, modified to make use of the S20's hemispherical combustion chamber shape too.

There are myriad other issues with this idea, and it really is a non-starter. The price of a good used S20 cylinder head alone would probably scare you off before you even got around to figuring what you would need to do to make it fit and work properly.

The Nissan "LY" or "Crossflow" head for the L-series six is such a rare beast in Japan that very high premiums are paid for them. The last time I saw an "LY" head for sale in Japan it was for a huge amount of money, and it was not even complete. Also, don't forget that the the proper "LY" used a different Crank, Rods and Pistons from the normal L-series engine.

I get the feeling that you are probably looking for more power, but that you aren't really a 'purist' or period tuning parts collector. If this is the case, then you are probably better off trying to get what you want from an L-series engine or going for a later model engine transplant. An RB25 swap would be far more easy and economical than the above options, for example.

Alan T.

PS - Just in case you haven't seen the business side of an S20 head, here's a picture of mine which is awaiting rebuild at the moment:

[St.stephen]

Alan, your knowledge is almost frightening!!!

But extremely appreciated as far as this guy is concerned :classic:

[brianglawson]

wow thanks for the info it was just an idea..

i am planning for and rb26dett but im looking at all possibilites and i wasnt familiar with jdm datsun motors but thanks for the info

p.s. i love your cars man you have some sweet rides

p.s.s. i will keep dreaming but how much was your twin cam motor, that would be sweet and they are such a beautiful piece of work, i wonder if rebello racing has good products???