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hey guys my skyline has hit 170,000 and the bottom end has decided to turn into a oil chewer it does 800km and drink 4.2liters of 40/70 :thumbsup:

yes thats right its ruined, anyway my uncle has gone over the car and all i need is to get new cams and he recommends changing my bottom end now because the compression test showed its 35psi down on the 5th cylinder than the others and they will want to die soon so thats y im going for a whole bottom end. My mate brought a rb25 and took the head off for a VL show car and said i can have the bottom for 300 and its only done 60,000km i checked it and its fine.

all i need to know is because its come from a Auto and a Rwc car

i have a manual and a gts4

the 4wd system is no problem i believe?

but im not sure on the deal with the automatic? A nissan mechanic guy i know said i will need to switch the sumps around so its got my old manual sump on it but i didn't get to talk to him about any other things

info about cams and bottom ends and such would be muchlyyy appreciated ;)

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a different cam should have nothing to do with bottom end???

an auto or manual engine should also make no difference, just change the flywheel over. But for 4WD the sump will be be different between the 2. I'm not sure if there are any other differences though. Also, i severely doubt your cars done 160,00 original kms, double it and you get a more accurate amount its probably done... "checked it and its fine" how exactly? You'd prob get more help in general questions as this isn't really an N/A specific topic.

what were the results from the compression test? You said 35psi down on cyl 5, but compared to what? 4.2L of oil is a lot for such short distance, sure it doesn't have a leaking seal as well? Does it actually blow blue smoke? If i was in your position, i'd be more inclines to just rebuild the old motor, new seals, rings and bearing, bit of a block shave (you could safely bump the CR up .5 or so for a bit more go). Car will go better than ever, and you wont have to worry about any of it again.

What are you acctually asking? How to put on a 3L bottom end?

http://www.skylinesaustralia.com/forums/RB...sions-f184.html

(3L conversion section of the forum)

http://www.skylinesaustralia.com/forums/Po...sp-t194033.html

(first page. A short rundown on how its done)

Dont bother doing cams. It will have absolutely nothing to do with the block.

Clyinder 5 - Is the PSI press 35? Or 35 PSI lower than the others? This could either mean Rings or Head gasket. Either way, the head has to come off. You could quite easily replace the block with all components for quite cheap. You could keep your block and replace and freshen it up - New bearings, rings, hone, etc. etc.

In terms of converting a 3L block to mate up to the front diff, its not that simple. You need an adaptor plate. Cheak the RB30 section of the forums to see how others have done.

If your going to take your engne apart you may aswell work it abit aswell. Again, see the NA sticky.

What are you acctually asking? How to put on a 3L bottom end?

http://www.skylinesaustralia.com/forums/RB...sions-f184.html

(3L conversion section of the forum)

http://www.skylinesaustralia.com/forums/Po...sp-t194033.html

(first page. A short rundown on how its done)

Dont bother doing cams. It will have absolutely nothing to do with the block.

Clyinder 5 - Is the PSI press 35? Or 35 PSI lower than the others? This could either mean Rings or Head gasket. Either way, the head has to come off. You could quite easily replace the block with all components for quite cheap. You could keep your block and replace and freshen it up - New bearings, rings, hone, etc. etc.

In terms of converting a 3L block to mate up to the front diff, its not that simple. You need an adaptor plate. Cheak the RB30 section of the forums to see how others have done.

If your going to take your engne apart you may aswell work it abit aswell. Again, see the NA sticky.

haha

yeh sorry guys it was a rushed topic and i wanted bed

yeh general questions may be better but i was hoping to hear it from a N/A point of view.

by the way its not the rb30 bottom i am looking for i just want to keep it a rb25.

haha, i know cams are on the top end its just im taking the engine out i wanted to change them to a better than stock part and just wanted to hear some good cams to go with if any of you know some?

yeh i talked to my friends dad

all he said was change the sump, so thats easy.

yeh the blue smoke pours out in 1st and 2nd

people behind the car blow the smoke away from there face if they cross the road behind it :blink:

a rebuild would be like building a engine back to new, but i dont think im worrying about that at the moment because its only my P's car and if i can keep it in good condition without spending a lot and get some power ill be happy with it :)

and because its a 60,000km engine my friend has sitting there and ive looked over it for scorch marks and such it looks like it wouldnt have been wound back so $300 is my bargain for me ill just change the ring and the bearing and etc because there pretty much a must my uncle was telling me.

thanks for feedback on what you could bring up ill take a look around the general parts

but advise on a style of cam would be appreciated :rolleyes:

P.S im getting the papers off my mechanic i left them there at the shop but i remember the psi from the compression test was not far off the stock psi from stock excluding the 5th cylinder.

if you can get the rb25 bottom end of your mate for 300 bucks then go for it

if the 5th cylinder is low on compression then i would most likely say that its a combination of rings and ring lands that are gone, and most likely the bore is seriously scratched

get the block of your mate, drop in new rings and bearings and put your head back on and voila - newish engine again

i went for a look at the block today at the workshop and its AMAZING CONDITION! :)

yeh the engine is just getting more and more thirsty for oil so now to do the labor ... :thumbsup:

your mates engine, was that definately a na rb25? its not a rb25det bottom end is it?

Also your gts4 rb25 block will be wider to accomindate the front diff, so im 99% sure it wont just bolt up.

I know you can go the other way, use a gts4 rb25 and put the rwd sump and it will work fine, but the normal rb25 rwd block doesnt have the holes for the front diff to bolt up.

Just worth checking into...

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