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onehotaccord
03-01-2006, 02:09 PM
i bought this 87 accord head off ebay and when i open the crate today it is a dohc b20a3/5.:thumbdn: i dont know which. but before i send it back for a refund and swallow the shipping costs i am wondering if it is possible to swap the head on my a20a3, or even on a 90 teg b18a/b. i search forums and found some info on b21 head swap in progress and conflicting statements on a b20 head swap.

Immeraufdemhund
03-01-2006, 03:13 PM
well i'm actually trying to do it my self. You'll have to do some wiring and get a b20a5 ecu (i think it's pk2) for what ever tranny you have. Then Jb weld some of the oil ports that stick past the block. I'd use the a20a3 head gasket. If i'm not mistaken you might...big might... have to redrill the center head bolt.. which is not a big deal if you have a machine shop do it. then just jb weld the hole that isn't used. It's a bit of a project, but i'm of the opinion it will work. oh yah. Also do this with the motor out of the car. If i remember correctly they were comeplaining that the valve might hit the side wall. Grab some vasoline and put the head down some what tight (use the old gasket) and turn the cams all the way over a couple of times. Obviously stop if there is any sign of it hitting the side wall. and then take the head off and observe the vasoline... If it's all good and not hitting your side walls continue with the work. I'm fixing to do that very thing here in about 2 weeks so this would be good if you did it for me first!

let me know for sure.

snoopyloopy
03-02-2006, 08:53 AM
read this thread: http://www.3geez.com/forum/showthread.php?t=47597

Immeraufdemhund
03-02-2006, 01:11 PM
looking at a couple of different threads holds different conclusions on the matter. Some say valves hit, some say sleeve spacing is different, some say too tall... I put a head gasket form a a20a3 on a b20a5 and it appears to fit perfectly, only way i'll know for sure is when i put the head on. I'm going to try and make a running version outside of the car, but i dowbt it... i dont think my engine stand would like that..but my hoist might.

from what i see you have to move the middle bolt and jb weld up some of the oil passages that let oil back down to the crank case, not a big deal. anywho.. guess i'll find out soon.

Immeraufdemhund
03-09-2006, 04:38 PM
well i'm getting further in the wire harness. I wish that i could just cut off everything cept the computer and wire in the 3 wires that i need for the dash stuff. But i also need the main relay and need a few others, i have a good wire diagram i might just go ahead and cut the harness, put in for the computer and then just tap into existing power and make the main relay and computer have power.... infact i think that's what i'm going to do, but i'll wait for someone to pipe in...if not OFF it GOES!

Just a couple of weeks and i'll have the accord to work on, then i'll know for sure. The engine needs probably a bottom end, and the top end on the prelude is in great shape. I have a question about that. It has 2 valve springs...maybe even 3 but i can't tell.. is this normal? i haven't seen a honda yet with 2 vavle springs. I've seen performance kits with it, but not stock. any idea? If that's the case does this let me rev higher?... guess i should just dyno it and find out. Thanx