questions about 280z

[Wolfwood]

Hello, this is my first post on automotive forum (or any actually). Please let me know if I make any mistakes in the protocol. I searched and did not find any matches for these questions. Here's the background. My father has been the owner of a 280z since he purchased it new in 1975. Since I've been young he's saved it with the intension of passing it on to me. Now that its mine i would like to improve its performance since it is not very powerful. It has 160,000 miles on it, but runs nice. Also, i should say I have no prior mechanical or tuning experience up to this point, and this will be my first sports car. Here are my questions: Is there a performance aftermarket for this engine? It seems most people swap in a V8, but thats not the route i would like to take. Does anyone have any suggestions for working with the stock engine? Next, according to my research, a 1975 Z has 149hp, but i know here in california was the only place Zs had catalytic converters, so does my car have less than Z's from other places, if so, how much less. I think the car is so old that it no longer requires smog checks, should i take it off to get the hp back? My last question is just curiosity. I've read the curb weight on a 280z is 2875lbs, and a 240z is only 2355lbs, besides the big bumpers, and fuel injection on the 280, does anyone know what else made it so much heavier? Thank you for reading my post, and I'm happy to be part of the forum.

[MikeMan]

Some people swear by the L series engines and some people think they're the worst engine ever designed. I think I fall somewhere in between.
Best performance mod you could do would be to replace that engine in my opinion. The 280z has a rather large engine bay that gives you quite a few options. You could swap in a RB25DET (skyline), a SR20DET (silvia), a KA24DE (240sx) or a VG30DE (z32 300zx) all of which will give you more power and a more solid base to start your modding adventures on.

Keep in mind though that an engine swap is not a walk in the park. There are going to be difficulties, and your car will be off the road for quite some time (I'm doing a vg30de swap and my car has been off the road for close to a year now). Thankfully though, you've got all of us to give you a hand too (providing you swap a vg engine in. )

If you're looking for bolt on mods, look into the difference between the 280z and 280zx engines, because you might be able to throw a 280zx turbo on your engine or whatnot. If you don't like turbos, a good set of headers are well worth the money. Together with a decent shot of nitrous, you're probably looking close to 230 ponies.

Cams are a waste of money unless you've already modded other aspects of your engine. Racing cams on an otherwise stock engine wont make anywhere near as much difference as racing cams on a decked out engine. Cams generally tend to complement other performance mods.

Don't muck about with underdrive pulleys, cold air intakes and mufflers because the only way these are going to make any real difference to your times is due to your wallet being that much lighter.

-Mike

[Moppie]

The 280 is a physicaly bigger car than the 240, combined with more sound deadening etc it all adds up to more weight.
The 240, upon wich the 280 is based was very much a sports car, with performance its main priority. However as it progressed through the 260 to the 280 it got bigger, heavier and became more of a GT.

The L series is IMO a great engine.
It was orginaly a Mercedes engine, but Nissan purchased the rights to build it under licence.
It will actualy bolt directly into a similar year merc with the same engine in it, and there are a few mercs running around with Nissan engines in them.
If your interested in doing a simple swap, then a Twin Cam from a merc will bolt right in, and will even let you use the mechanical fuel injection.
They have a fair bit more power and torque, altough finding a good one thats a good price will be difficult.

Swapping any of the above suggested engines will require some serious work. Mostly getting the car wired for the electronic engine managemet systems they use. Its possible, but would be expensive.

The best thing I can think of for your car, if you want just simple improvements done to the existing enigne would be some nice headers, a ported head with cam to match, and rebuild of the injection system to keep it all running at its best.

Any real increases in hp will however require more work.
Starting with a complete engine rebuild to handle any increases in power.
Once you commit to that level then swapping in a RB25det becomes a viable option, and given the increase in hp is well worth it.



Anyway, welcome to the forum.
Right now, I personaly think what you should do is simply enjoy driving the car, and learning about it by doing basic maintiance.
Its of an age where lots will go wrong, and you will have lots to learn from. Then when your ready you can start on more major improvements.

[Wolfwood]

I appreciate the information guys. It's given me a lot to think about as I consider what route I want to take for improving my car. I was thinking I didn’t want to do anything too radical since I don’t plan on racing exactly. It’s just that the thought of such a beautiful sporty car being slower than some of these stock economy-hatchbacks is depressing. I suppose my only goal for it is to be at least faster than pedestrian looking cars like the new civic si. But some of the points you've brought up make me think perhaps I should consider an engine swap when the time comes. Until then I will continue to drive it "as is", since I’m still having a blast with it and its running so well. When the time comes I will look into the other engines you both mentioned, the Mercedes dohc engine sounds interesting, but it seems like it might be hard to locate. The newer 280zx engine sounds like a practical option, although the skyline engine really puts some ideas in my head. How hard would it be to find that engine, which I think is only from Japan? Also would replacement parts be very hard to find for that engine? Finally, how much do you think one of these engine swaps would run out the door engine and labor? (so I can start saving now if it’s steep). Thanks again for your answers, they've really been helpful to me.

[DeleriousZ]

just give samhain a pm, he can hook you up with all sorts of engines from japan... he's the man when it comes to swaps

[RX_speed]

if you dont want to spend much money then swapping in the L28T (280zx turbo motor) would be a good idea. It would be easy to perform and has more than enough potential for your goals. With a not-too-over-the-top turbo upgrade and other basic mods you could have a budget 13 second car. just dont forget to upgrade your suspension so you can tear up those Civic SIs in the twisties

[MikeMan]

Originally Posted by Wolfwood

Also would replacement parts be very hard to find for that engine?

No way jose. Easy to find, but expensive because its a niche market.

Originally Posted by Wolfwood

Finally, how much do you think one of these engine swaps would run out the door engine and labor? (so I can start saving now if it’s steep).

It's cost me about $7500AUD so far.
- $1800 for the VG30DE + 5spd box
- $2000 for the custom headers (you'd understand if you saw how cramped the driver side of the engine bay is with the engine in there)
- $800 to get the DE ECU wired up to everything
- $2000 for labour so far
- $400 miscellaneous towing etc.
- $500 in parts

Then I still need the custom tailshaft made up and i need to get the car blue slipped (change of motor registry details for new vin etc.), engineered and rego'ed.

Keep in mind though I also did an AT to MT conversion too. And those headers really killed me, which probably wont be the case if you're throwing the RB in (its inline, more room around the sides of the engine)

I'd say save up a good $5k USD which should get you out of trouble. Besides, if you've got some left over, I'm sure the car could do with a new paint job, interior etc.

-Mike

[Pistolpete]

i reken you should go with the L28T aswell
its a pretty solid motor and with a nice turbo urgrade u could b flying

its good to see that ur looking to to up an old Z the newer ones are nice but u cant forget their older bothers.

[Wolfwood]

I think i will start setting aside some cash for an engine fund right away so the money will be on hand when the time comes. It's funny how the more time i spend on automotiveforums the more my performance expectations for the car have threatened to grow .