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yeah i own a l20et and i know that. lol. i was asking what head is on the l20et? cause i have a spare one and i'm trying to identify what i can do to it

Sorry...didn't have my glasses on when I read that :D

Never seen one that close, although almost bought a Fairlady Z with one in it once. I read somewhere they had a unique head, something like 'OS' or '05' as the identifier. Don't kow any specs.

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CAn it be used on a l20et ? raises the compression to 7.9 i think ?

not entirely sure to tel you the truth, i havnt experimented quite that far yet :rofl:

but maybe this site will help http://en.wikipedia.org/wiki/Nissan_L_engine

edit: by the way, the N42 head a highly desireable and efficient all-round head for the L28. altho its not the best, as SteveL said they are probably the most popular for price and working order.

also if you want to identify what head is on the L20ET then have a look around the spark plug area where the head meets the block ( from memory) and there should be a imprint of what the head is called. the numbers may be located on the opposite side tho, just have a look around it and im sure you will find what your looking for

Edited by Brycey
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I would tread wearily with large valve heads on L20a's , my references show them as having 78mm bores and 38+33mm valves so 71mm across them . Late L24's use 42+35mm (77 across) in 83mm bore . L28's used 44+35mm (79 across) which is wider than the L20's bore even if they were touching in between .

Cheers A .

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I'd be laying the L24 head gasket on it just to be sure . You will find with the L4 and 6's helping the exhaust side works well . Unless you intend to use only high revs the 44mm inlets will cost you gas speed and torque . The first (early 81) MR30's got the best head and the large exhaust valves from memory - best chamber design sort of like L16 SSS 219 castings . I would use it over any L6 head . You can change valves but not chambers , welding is not cost effective .

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