DJZ's other other 2 seater 280ZX

[nzeder]

Everything is for sale

You are not wrong there. I am thinking I might have to part with one of my 260z 2 seater.

Hope you are happy with all your parts. Moving them on made room in the shed so I could get my 2 L6 and other parts home and out of the parents place now that they are moving.

When I installed the rear z31 rb sump the pistons looked new or newish from the bottom and the rods had been polished iirc.

[DJZ]

Swapped the front crossmember over to the manual rack & pinion one on the weekend, the shaft is too short to get to the steering column and it actually looks smaller in diameter than the other one, I need to pull the bush and flange off the other car, hopefully I won't have to change the column.

Pulled the RHS control arm off to put the new bush in, was pretty easy except I put the arm in upside down the first time haha, wondered why nothing lined up. I changed the sway bar mount bush and will put the new link bushes tomorrow.

I took Bart's borescope to work and pulled one of the plugs out, it's actually got NGK racing plugs in it, I couldn't see much in there as there's a fair bit of carbon on top of the pistons, they possibly look like they are flat top with quite big valve reliefs. Will try and lift it up with the forky tomorrow and have a look in the sump with it.

[DJZ]

Couldn't fit the borescope into the sump so I pulled it off to have a look, good thing that I did, it's actually quite rusty inside, not sure why, maybe condensation? It definitely has an RB26 crank, the rods have been polished, the pistons are cast but other than that have no markings on them, it has standard rod bolts too by the looks of it.

I'm tossing up what to do now as there looks to be a bit of rust at the bottom of the bores, I can probably get rid of most of the rust that's in there but it might be best to pull it all apart to make sure everything is good.

[DJZ]

What's a good image hosting site that isn't Photobucket?

Mmm, rusty.






Polished rods, they've ground all the markings off them so I don't know what they are, can't easily measure the length with the in the block.

[DJZ]

Started pulling the front end apart, it has a standard oil pump (probably RB25) and narrow oil pump drive.

I'm not sure what the compression ratio would have been, I can't find a number for the piston dome CC's but I think it must be pretty high judging by how much of the piston is sticking out above the deck.

Combustion chambers looks to be standard, they are pretty carbony, I think it's been running very rich, I've cleaned this one.




Pistons are standard diameter RB25DE ones, again quite carbony, I've cleaned this one a bit.




Head gasket measures up at about 1.3mm, it looks like it's been leaking in between a couple of the cylinders, bit hard to see in the picture but it's green in between the chambers.




There's a few marks, rust spots and stains in the bores, I think it's going to need a hone and a new set of rings.

[2 doors]

so is this supposed to be a sweet motor ? seems a bit of a bugger, although not a hard fix.

[DJZ]

It's been sitting for a long time, which I knew, it hasn't been run since before 2007. I found some piston specs which makes the compression ratio work out to be about 11:1, maybe slightly higher as there is some conflicting info about the piston pin height.

It gives me a chance to clean things up and upgrade a few things, I'm not sure what to do with the head, I might actually keep it for the black car and build another one for this. Or I could go back to the original plan and put the RB25 Neo in it.

[2 doors]

ahh I see, you must just about have your own engine shop round there by now lol

[DJZ]

Got the bottom end apart, looks like it was pretty close to running a bearing, the pictured one is the worst but the rest of them all had marks. The crank itself looks okay, I think it'll come up pretty good with just a polish. The bearings are genuine Nissan ones.

[DJZ]

So going back to the original plan of putting the RB25 Neo in this I've started work on the inlet manifold, got quite a bit done so far! Sorry about the terrible photos, I was rushing.

I bought another inlet manifold and cut it up, got the guys at HBI to mill it flat for me, for free too!




Bought a piece of 12mm plate from Little Metals and marked out the three throttle bodies on it, it's not perfect but it's pretty close, I should still be able to use the original RB26 plenum if I wanted to, everything lines up well enough for that. The step is basically for matching the throttle body holes to the manifold runners, the throttle bodies are 45mm where the running inside diameter is only 36mm, but some of the runners don't line up 100% so there's going to be quite a lot of grinding.




This is a throttle body sitting on the plate which is sitting on the runners, you can kind of see where there is excess material that needs to be removed to get everything kind of smooth flowing. I will need to cut a few bits out of the piece of plate to clear the throttle linkages.