Suggestions for 75 280Z

[Dirwin]

I bought what I think was a really nice 75 280 last year. A represented 39K mile, nearly original, nice car. After climbing all through it, I believe that it is a real 39K mile car, but who knows, after 10 years, it's exempt on miles in Texas anyway. It has been painted, but the work was done very well and it has absolutely zero rust, or prior rust repair. It had what I think were some old Panasport knockoffs, fronts were 14x6, rears 14x7, taller tires on the rear, looked like hammered crap. Seller said they were Panasports, had the blue Panasport center caps, at least 3 of them did, the 4th the same blue raised decal but was a different cap, held in the wheel with duct tape by the way. Regardless, I didn't like them so I then went and refinished a set of original 14x5's with 195/70's and hubcaps and installed them, if it's possible, it looked worse (in my opinion).

Finally, I decided on where I am now, 15x6, 15mm offset, real Panasports, 205/60R15 tires, seems to fit very well and looks good to me.

Now to my questions. I want to drive this car more but I have a few issues with it. And really would like some opinions from you guys.

1st, it squeaks and rattles just as bad as my 78 did when I bought it in 82 (why I bought this one you ask? My first car was that 78 280Z). I've searched and read on this issue and I know about the greased rivets and closed cell foam tape so I'm good here I think. Anything else? It actually feels like the whole body is flexing.

2nd, my drive to and from work is 18 miles one way, nearly all highway, 70-75 mph, the original 4 speed is really zinging the engine. Is a 5 speed a good swap? It seems pretty straight forward but are there any bears that are going to jump out at me when I get started?

3rd, the car is a factory A/C car, everything is there and it works (fan, defrost, etc...), just doesn't blow cold. Is switching out to a new Sanden compressor and a R134a conversion worth doing? I'm in Texas by the way.

4th, even with low miles, the oil pressure seems to stay on the low side, especially at idle. It will come up when you get going but get lower as the engine warms up (and the oil thins). I changed the sending unit already. Should I go ahead and replace the oil pump? Could it be caused by something I'm not thinking about?

5th, struts and suspension which are all original, is it time to go ahead and go through the suspension? Will this correct some of my squeaks and rattle issues? My goal is good ride and handling for the street, the car will never be raced or auto-x'd. I'd like it to handle a little better but I'm concerned as to whether going with the Tokico struts (or something along those lines) and droping the car 1 inch will cause my 205/60's will rub.

Last (at least for now), alternator, headlights dimming with RPM, all the issues you run into with the low amp alternator you'd expect. Is switching out to the bigger internally regulated alternator worth doing? What kind of issues am I going to run into?

My original thought was to keep the car bone stock, but now, I'm changing my mind, I want to drive it. My goal is now to get it to drive as nice as I can and enjoy it. I already know I paid way to much for it when I bought it, but it brought back a lot of good memories, and it's not that I'm looking for resale or anything like that. I don't plan on getting rid of it.

Like I said, my first car was a 78, silver with a 4 speed. I bought it my sophomore year in high school after saving up 2+ years of lawn mowing money. It burned a quart of oil every tank of gas, but I absolutely loved it. Too bad I couldn't afford the insurance for it at the time and had to sell it after my 6 month policy expired, just of one of those things I guess. Now, 30 years later, I can afford the insurance! Funny though, my girlfriend at the time, hated the car! Now, 30 years later, after we've been married for nearly 24 years, she still hates it

I've been searching and reading on this forum for over a year now. I don't post much but any input you guys could give me would be greatly appreciated.

[Wade Nelson]

My recommendation: Buy oil in bulk and dump the GF. Install a decent stereo and some good speakers and the squeaks and rattles will magically disappear.

You mean as rpm's drop the headlights get dimmer at night?

I'd suggest you take it to an auto electric shop and have them do a charging system analysis (about $75) before I did ANYTHING. If you're resistant to hiring professionals, then measure your battery voltage (engine off, idling, 3000 rpm) and report back and I can perhaps give you a "next step." You SHOULD be seeing 12.5-12.6, 13.2 or so, and 13.8 or better at those three points. Regulators DO wear out and instead of trying to replace or adjust 'em switching to an internally regulated alternator IS a good upgrade, PROVIDED ITS DONE CORRECTLY BY A QUALIFIED AUTO ELECTRICIAN.

But you CAN have a lot of fun if you're willing to screw around and learn how to adjust your regulator. Dial it up to 14.4 volts or so and you can turn your headlights into flamethrowers. Get a spare or junkyard unit to play with until you figure out what you're doing.

Edited February 22, 2013 by Wade Nelson

[SportBikeMike]

How can a woman hate a 280Z?? Both my Zs get compliments from girls all the time. Is she blind or something?

BTW very nice car!

[Dirwin]

Well this got a little easier! Decided to drive the Z home tonight, now I'm 6 miles from the house waiting for a wrecker, . Alternator took a dump, low voltage got to the fuel injection, here I sit. Just like old times, my 78 did this to me as well.

Can't dump her now! She was my GF 30 years ago, she's now been my wife for nearly 24!

[ksechler]

1). squeaks and rattles - I don't know but starting with #5 is probably a good idea. I would imagine those rubber bushings are pretty dried out after 38 years in Texas. God knows what the strut inserts look like.

2). Yes, try the 5-speed. Go to hybridz.org and search the archives. I think there are several 5-spd options that are plug and play, but I have not researched the issue in depth because I planned to keep my 4-spd.

5). 205's shouldn't rub. The Tokico struts won't drop the car, the springs will. If you plan to do both that's ok, the 205's still shouldn't rub.

If your wife makes you sell the car let me know. Maybe I could take it off your hands! ;-)

[Wade Nelson]

If your wife makes you sell the car let me know. Maybe I could take it off your hands! ;-)

The wife or the car?

[Dirwin]

You're right, the suspension might correct some of the squeaks and rattles so I'm going to start there. Is there a source for ALL of the rubber bushings in a kit form? I do not want to go with poly bushings because I don't want to roughen the ride that much. Also is the Tokico the way to go with the struts and springs?

[IdahoKidd]

Definately do the 5 speed. It is a direct replacement. ZX 5 speeds are plentiful and about a $100. (can't use the turbo 5sp). I installed a headlight relay kit that was essentially a direct fit and put in off the shelf wagner halogen sealed beams. Can not overstate how much that helped. The relay kit takes the voltage off the switch. Got mine from Summit for something like $39. Didn't cut a single wire. The clunk on a bump on mine was from a bad strut. The top mount was loose and the strut moved up and down before compression. I put in new ones, nothing special, and the bulk of the noise went away. Still a few squeaks, which now just gives it character

[Pop's Z]

Hi David welcome to the best zcar forum. If you are concerned about the ride quality you might consider staying away from Tokiko struts and springs. They are very firm. I went with Eibach progressive springs and KYB struts. The ride is firm, but not harsh like my friend's car w/ the Tokikos. As far as rattles go search them out and fix them. The plastic finishers in the back (there are 5) held in with plastic pins can be a real source of squeaks and rattles. Get a pair of strut tower braces which will stiffen the body up a bit. Look into insulating the cockpit with sound-deadening material...many have done this and there are various threads about it. I used "Q-Pads" and commercial duct insulation and my car is pretty quiet. Take the car to a good A/C shop and get the system checked over. You may not need a new compressor and a conversion to R134 is not very expensive. Texas heat requires a good working A/C. Good advice on 5spds...try to find a 280ZX one. You will appreciate the o/d 5th gear. Good luck and keep asking questions. That's how we all learned about these great cars. FWIW, my wife loves my car...she calls it "the acceptable mistress".

Cheers, Mike

[mjr45]

I put a 79 ZX 5 speed in my 75 with no issues. Sound deadening material thru out the cockpit helped a lot with some of the squeaks but you're dealing with a 38 year car, so you have to expect some rattles, I even used contractors expanding foam in some places to help with the hollow sound on some panels. The headlight relay kit is a great idea as well.

[Pomorza]

Dirwin

A five speed conversion is a rather good conversion to do if you're doing mostly highway driving. Its pretty much a swap and go type deal. For what I remember most if not all 5 speeds uptil they switched to the V6 motors will bolt right onto your car. The "best" transmissions you can get is from the 80's ZX (80-83 I believe - minus the turbo one apparently) - according to may - as it has better gear ratios. I've done two of these myself its really not the hard just time consuming - along with oil covered. While your in there I suggest you do the clutch, throwout bearing and pretty much anything else related the the clutch system - I've made the mistake of not swapping in a new clutch, three weeks later no more clutch.

As for you oil problem. Two questions - what oil are you running and have you confirmed low pressure with a mechanical gauge? The stock Z gauges - while awesome - are 30+ years old and can read poorly after time.

Hope that helps

Jan

Edited February 22, 2013 by Pomorza

[tamo3]

Welcome to classic Z car forum. You got nice 280z!

As many people recommend, swap with 280zx 5speed. 280zx gear ratio is better than 280z gear ratio on 5th gear. You'll get better millage.

Regarding alternator swap, there is several options. Go for 280zx IC alternator is just get lid of external regulator and maybe less issue with IC. However, it's same capacity 60amp. I don't think you can expect better charging capability.

Nissan/Datsun Z Car Voltage Regulator Conversion

If you go for CS130, CS144, GM Delco-Remy 10Si, 12Si, those generate more, but what I heard it require higher RPM to charge and lower RPM is less charging compare with original alternator.

Thus, as many people recommend, I think adding relay for headlight is one of the best solution in your case.

Good luck!

tamo3