N12 Turbo Forums

Oops, nice piston!

What do those those differing numbers stand for? My E16/E15ET piston rods are all stamped '51-1' on the left side of the Nissan logo, but they are all stamped 31M-x on the right side of the logo, just like your rods.

TurboZ.Dude wrote:Oops, nice piston!

What do those those differing numbers stand for? My E16/E15ET piston rods are all stamped '51-1' on the left side of the Nissan logo, but they are all stamped 31M-x on the right side of the logo, just like your rods.

I think they just refer to different batches of rods. I weighed the separate rod last night, and they all came in at the same weights. 337ish grams.


Damo

Ah, I see! Thanks m8!

Picked this up during the week. It is a head of a QG18 which is interchangable to a QG16 which is supposed to be based off a GA16, which is a progression to the E15/16!
I'm not in the same state as the rest of my N12 stuff at the moment, so I can't directly tell how much massaging would be required IF the bolt holes line up.
From what I can see, it needs a second oil supply from the block on the exhaust side, oh and I will have to weld up the front of the head where oil used to flow over the timing chain, and probably need to fabricate a timing sprocket onto the end of each cam.
I'll have it knocked up over the weekend!!!!

What do you guys think?:





The cylinder spacing is around 7mm, the comp chambers are 79mm, exhaust valves are 24ish mm, inlets are 30ish mm.
If it works, there will be a slight miss-match as the E series block has different spacing between #2 and #3 compared to #1 and #2, #3 and #4.


Damo

Keep me posted!

You know you are more then welcome to borrow my car to match stuff up man. I'm only round the corner.

And god knows if it works I will be the one that buys it off you ;P

The green machine is always keen for upgrades good man.

If you want me to come around and give you a hand buddy, just give me a call.
Its the least I can do.

Michael

WOW...
Just from photoshop, your photo and a picture of a head gasket
You my have something....
its so close, all the water jackets are lining up.
Sure there is a spacing issue but maybe a magic O ring solution might be able to fix that, and a really good machine shop.

But my hat is tipped to you sir... For having the balls to give it a go...
I know it can be done...
If its worth while doing....
If you pull this off... You will be a legend....
At least to me LOL

Id like to see how this pans out too!!

Just to put little dampener on this, the QG is not going to be a bolt on thing like the RB25 onto the RB30! There are going to be big problems with cylinder alignment, oil drains and of course, cam actuation.
The first thing I'll need to do it match up the head with a stocko E15 gasket to see if the bolt holes are in the ball park, more than 2mm and its game over. The 2 oil drains on the exhaust side should be able to be done externally to the block then collect at the turbo oil drain.
The oil feed to the head is on the wrong side of the bolt hole.
If I can graft two cam sprockets onto the end of the cams, they will need to be spaced out to match the existing crank sprocket, jack shaft and belt tensioner. Sourcing a belt shouldn't be a huge problem as long as the douche behind the counter is helpful. Then I would have to organize another CAS pickup point.
There is/was no way to have this done over a weekend unfortunately, so progress may come slowly.
Mind you, direct cam actuated DOHC for the E15 gives me wood!

BTW, if you are interested, the head cost me $5.50 of Ebay, pays to keep your eyes peeled!


Damo

Cant wait to see how this is gonna work! 16v dohc on an E15-16

Damo wrote: What do you guys think?:
Damo

WOFTAM!!!!!!

Sry... has to be said!!!!!
Cheaper and easier to use the entire donor engine!!!!! PMSL!!!!!

*tassuperkart ducks for cover*

Oracle!

tassuperkart wrote:

Damo wrote: What do you guys think?:
Damo

WOFTAM!!!!!!

Sry... has to be said!!!!!
Cheaper and easier to use the entire donor engine!!!!! PMSL!!!!!

*tassuperkart ducks for cover*

Oracle!

Should have clarified, Tass, you don't get a say.

If I had to pay someone to do the swap for me, had to take the car off the road for the duration of the meddling, and had to pay sticker price for the goodies, to potentially result in naught, yep complete waste of time + moolah. BUT, all the bits I need to make the sucker go together are sitting in my olds garage. Spare block, spare cam sprockets, a welder, grinder, and fuck-off big hammer, it will be sweet!
Besides, I want to know first hand how much of a headfuck it is going to be to make it work. Even if after it turns out that the complete DOHC swap is going to cost $1500 for the average punter, we have been around long enough to have seen at least 1/2 dozen $1000 head jobs come through the forum. I bet my left nut that if a solid shimmed cam on 16valve head was able to be sourced and fitted for $1500, no body would bother with 8 valve rocker stocko porting.
As far as I can tell, apart from the A and E series Nissan do not have a another odd cylinder spaced head that will even remotely look like fitting to the block. If the QG does indeed bolt on, that means the GA will as well, then it will come down to the individual to make the chosen head work.
It may prove simpler to replace the entire engine with the newer combo, but for some reason, I really like the idea of a genuine twin cam E15. So nar!


Damo

IIRC the GA head does NOT go anywhere close. On that basis, the one you are fiddling with wont either.
That meas your large hammer will indeed come in handy to bludgeon the shit out of the stuff you have....muwaaaahahahahah!
E

tassuperkart wrote:IIRC the GA head does NOT go anywhere close. On that basis, the one you are fiddling with wont either.
That meas your large hammer will indeed come in handy to bludgeon the shit out of the stuff you have....muwaaaahahahahah!
E

Not so fast old fruit! I whipped out ye old tape measurererer at Michaels place the other night, and the approx distance of the outer head bolts was as close as I could measure. Physically, the DOHC head is huge in comparo, but the gasket width looks the same. Time will tell.



Damo

Im going off an old discussion where the GA head was put forward as an alternative (and IIRC, YOU might have been in on it at the time). Im certain the gaskets were compared and the whole matter dismissed as a woftam.

However, if its frigging around for frigging arounds sake then why not eh?
Sounds like fun in a way.

To me tho, its still an exercise in futility as it would be far far easier to just fit the entire GA/QG/whatever engine to begin with and be done with it!

Oracle