280zx turbo into a 260z??

farstar

farstar

Well-Known Forum User
Its an age old need, more power Scottie!

The cars - 260z 2 seater and a 260z 2+2.

The problem - My 2 seater is pretty much a nut and bolt resto project that I acquired and finished so am reluctant to mess with it as everything is pretty much stock. She is still waiting for a few small jobs and running in when the weather improves.

The 2+2 is the car that I use and enjoy more often and I do love her dearly. She has a 280z engine (N42 head) and gearbox, 240z SU's, header, exhaust, etc.

I am thinking of ways to give her a little more go. In the current climate, I am not keen on upgrading everything and spending many thousands of pounds.

I have a friend of a friend who is selling a manual 280zx Turbo and was wondering:
a) what the gains would be over the current set up and maybe a few straighforward mods
and most importantly b) how difficult is the job? I am a novice and not a mechanic. I have a go or seek advice and assistance from friends and family in the trade when things are beyond me.

Guys, your advice and comments would be greatly appreciated. I think it would also be nice to have the view from those who have gone down the old school tuning route as a comparison of what the car would feel like, drive, cost, etc. Before anybody says it, yes, nothing in the world quite sounds like Webers opening up but the cost and fiddle factor is there...

Discuss gents and roll on summer! :rofl:
 
Hi Faz, You know my thoughts anyway but...

Stick it in the 2+2. Nice & easy job if you are doing it as a complete package, use the mounts off the 2+2, it is a bolt in job. The small wiring changes are well documented as per the EFI conversion. Only drawback might be the diff as The bushes / mounts must be getting on a bit. You might have to get the prop modded (depends what box comes in the ZX turbo, I think it was only the z31 turbo that had the T5???), but that will only be 90 quid or so. Engine hoist & some spanners... I've done it solo before but not advisable! It is just like giant lego. The turbo will give you plenty of top end boost and scope for further tuning too (intercooler, bigger turbo etc). Oh yes, you will need to persuade the powerflow and the ZXT manifold to mate, sure you have those sorts of contacts.

I will give you a call soon.

Cheers

Paul
 
You say it's a 280z engine but with 240 carbs. Didn't the 280z & 280zx have fuel injection instead? Or is it a 2.6 re-bore? The 260 had a 154 banzai horses under the bonnet so if you went for the 280zx turbo that would go up to 180bhp. The 280's tranny was the only thing that the first series had in common with the second so getting the power to the rear should be reasonably straight forward (I'm quite prepared to get hung out to dry on that one so do your worst pmac / all others who normally enjoy taking me down! :) ). That said once you've got that lump in there with the turbo it's a simpler mod adding power (and probably cheaper too). Whatever you do, keep us updated with perhaps some pics... or... keep it schtum and save it all for the magazine! Woop woop!!!
 
As we are in the UK, I assume the 280ZX turbo is a Janspeed conversion? Originally rated at about 190bhp, it can be persuaded to give a little more boost to top 200 bhp, but the "not too modern" system will become limited in tuning potential for much more. Best built with dished piston early engine coupled with later P90 head.

Don't forget that EFI will require a fuel pump change and that a non-baffled tank might also be a limiting factor.
 
I have gotten around the baffled tank problem by fitting a surge tank near to the tank, i have not see the Janspeed turbo conversion, so can't comment on it much but, I think the fuel pump and injectors etc as Mr F says will be your limiting factors a good T3 turbo will see 300bhp with all the right extra bits, but then you'll just get carried away like I did ..LOL..
 
True on another note, I have changed to Toyo T1R's on the back and the extra grip is outstanding just ordered some for the front, expensive, but it is the only point of contact with the road. not as easy to smoke the toyos as the yokos..
 
If the set up uses EFI, then another thing to consider is fitting a wider diameter fuel supply line.

One thing to bear in mind is that HP costs money, even when it seems cheap it always end up costing more.
 
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First off, a belated Merry Christmas and a Happy New Year to you all! :)

Thank you very, very much for all your replies, it is greatly appreciated by us young(ish) novices and newbies. Paul! How are you mate! I still have your bleedin' bonnet!!!!

Just to clarify, I'm not after a ridiculous amount of power, I find that the way Z's drive make them remarkably quick and fun for their age but a few more horses to provoke it a little more in the dry would be great (not getting shredded by mundane boy racer rubbish would be an added bonus!). If it all works out and there is scope for further improvement then that will come later if the need arises, and if the sword of Damocles that seems to be hanging over alot of people disappears...:unsure:

Soooooooo...it is a fairly straightforward job actually physically unbolting the turbo engine and tranny as a whole and dropping it into the 260z 2+2. I assume that the gearbox and transmission would come out as one and drop straight in lining up with the existing console and stuff?? Am I correct in saying that that the gearbox will mate to the 280z prop without modification?

Are the differences between the ZXT manifold and Mr. F's header greatly different?

The fuel pump would be uprated accordingly, any recommendations? Also, is the wiring for the EFI on a separate loom or do you have to take the whole lot out? Is it one for an electrician? Are there any other electrical changes required?

I'll probably stick with the original tank at the moment and change afterwards as a future mod. Out of interest, why is the change necessary?

Zed2K, I've Toyo T1S's and R's at the mo and they do grip some!
 
Turbo engines usually come with a specific manifold to which the turbo mounts. Janspeed used an adapter on the standard 280ZX cast manifold; genuine turbo 280s had a bespoke Nissan manifold. You won't be using a header manifold for NA with a turbo application...

The EFI loom is a separate item with links for power supply to the battery - the required mods to adapt are fairly simple (unless the donor really is a 280ZX turbo, then it becomes more involved...). Ideally you need to implement the ignition relay design of the 280 to cut the fuel pump in case of engine failure / accident.

No propshaft modification required.

Fuel pump could be the original 280ZX electric pump, or I can supply a suitable new aftermarket EFI pump and appropriate filters. Note that EFI pumps generally run close tolerances and MUST be protected from tank debris with a pre-pump filter or significant in-tank gauze (which the 260Z does not have). Similarly, they don't react well to running dry, hence the need for a baffled tank or an independently fed swirl pot to protect the pump. If you run without, don't risk running out of fuel and always keep the tank well topped up.

Your 260Z manual box probably has better ratios than an early 280ZX manual box - the second to third gap is excessive on the early 280 (although turbo power does quite a good job of covering this up!). As an alternative, use a later 280 box to gain the advantage of the improved synchro design or stick with the 260 box. All boxes bolt up to the engine O.K., but check the clutch specification / release bearing clearance if the 260Z is an early car.
 
Hi Faz, you have the relays to cut the ignition already (for the gas conversion), and that electric fuel pump should be fine if you are not wanting silly amounts of power. You could most probabally get away with a swirl pot, but if you do that you will need a secondary electric lift pump to fill the swirl pot from the main tank. You need a swirl pot (in or out of the tank), or baffles, or a sump (or all of the above) to stop fuel starvation or air bubbles under heavy braking / cornering / acceleration. You might damage the injectors or in severe cases and if you do it a lot the engine (from running too weak).

I might have a 2+2 tank which has been modified (slightly less capacity) & baffled available at the end of next year, depending how my plans go.
 
This could end up being a really sweet modification so be sure to keep us updated. Pretty much everything is positive and so all good. And having near 200 horses in a car that's just shy of a tonne is a wicked amount of power! Bear in mind the Astra VXR & Focus ST with 260-280bhp are 1.5tonnes with all the new sound dampening and safety gear. A 2be2 with 200bhp is a superb bit o' kit. Love it!
 
Chaps, this is fantastic! All the info is much appreciated!

Lets just hope that the engine and peripherals materialise to do the swap. If all goes well, I'll start posting pics and questions (probably more of the latter!) for all to view, digest, criticise and comment accordingly.
 
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