Post by
aux »
https://forums.nicoclub.com/aux-u118286.html
Tue May 18, 2010 12:16 am
usually when ppl repost w different wording, its becasue they are either frustrated or annoyed by the fact that nobody knows wtf they are talking about, or just had no responses @ all. im trying to find someone who's used 90 sohc pistons in their de, but even though there seem to be a few on the internetz, none of them want to talk w me about it, or just havent happened across my post.. kinda gay.
first off, i'm assuming you're only planning on burning 93+ from now on..
what you should do is find a crankshaft kit, for as cheap as possible. a matched crank, w fresh journals completely stock measurements is the best way to go. using a used crank is a dumb idea, bc its already been worn on and youll have to polish it w emery cloth to clean the surfaces, which loosens up your clearences, or you will have to take it to a machine shop, and have them cut it to fit oversized bearings and have it balanced, but its always more secure going w a new one.. then u can use the sohc/dohc rods, pins, pistons, etc. w a fresh set of STD bearings, and wont have to worry about if rod 1 is looser than rod 3 or is out of balance w rod 4 etc etc..
but yea dude, u can use the sohc pistons.. thats whats going in my rebuild (just got it down to the block today) but make absolutely sure you are using the ones from the 90 block, bc if u pull from an 89 youll end with an 11.6:1 which is bad news on the factory map and normal timing. however, if u purchase a set of "new" sohc pistons, they will be the 90 pistons, bc in 90 nissan lowered the comp in the E to 8.6:1 i believe, which yields 11:1 in the DE which is what i have gathered after doing much research. @ first, i thought ppl were nuts, bc i thought well.. how would u use 12 valve pistons in a 16 valve head, but then i found that they are flat, unlike the DE pistons which are dished, w neither having cutouts..actually, i just ordered a set of brand new beck/arnley new old stock '90 sohc pistons, a kit all 4 w rings, pins, etc.. for $25 freakin bux shipped (wholesaler clearence) from rockauto.com. the sucky thing is now theres only 3 sets left.
but the big issue is going to be the tuning. now im thinking everything aught to be fine, by just retarding (=B) the timing a bit.. my factory map seems to be kinda rich.. there's always a bit of unburnt fuel exiting the exhaust, but im also running in open loop (o2 sensor unplugged) bc of shot gasket @ the manifold. but if there isnt enough fuel, then il just increase it by opening the maf, and if its mechanical like the old toyota ones, adjust the gear and advance the fuel mechanically.. and if i cant do that, then oh well guess ill have to use a piggyback to get around the problem, like a used safc for 100 or something. in your case, you should really look into it as i am attempting to, or else we will have screwed up engines after all that trouble. good luck mang
