gergstuff

Hello!

I just acquired a '73 240Z (and a bunch of other cars and stuff) in a trade.

It runs, barely, and last night I was able to get the clutch to work and it to move under it's own power.

It smokes (blue) like crazy so it must be very tired (have to check compression,etc.).

I was doing a Craigslist search for motors and used ones are out there fairly cheap although one never know what they are getting I suppose.

I wondered if there was any major advantage in getting a 260 or 280 engine over the original? I don't really want to mess with fuel injection and so on so I would want a drop in replacement motor. How late can I go year/motor wise before I start running into extra work on a motor swap?

Always wanted a Z and I probably should have gotten a better one as I know from experience it is better to shell out the cash up front for a nice one of anything you want rather than try to turn a sows ear into a silk purse. Kinda like you can't polish a turd...

I would thing rebuilding the existing engine would get expensive in a hurry.

Any helpful advice is welcome.

Thanks,

Craig

zxguy1986

Welcome to ZDriver!

Pick up a freebie factory service manual at XenonS30 and check out the other cool docs. Parts fiche! awsum. You will use them, I am sure. Great way to reference your questions because all our S30 pros have the same docs.

Car sure needs work. I guess if you have the time and bucks, you can bring it back to whatever performance/appearance level makes you happy. In your next post for it, give our guys the scoop on mileage, motor (original or modded), current condition, and your best assessment of everything you have checked out - plus what you want from it when you're done. Photos are almost a necessity here. Guys have to see what you're dealing with and talking about.

Meanwhile, sign in, go to User CP menu (upper left), click Edit Signature and add your Z model, year, shifter, turbo or NA, mileage, etc. Saves you having to add it every post. (Guys go crazy if you don't lock all of your Qs to your specific Z, every time you post...) Then click Edit Avatar and add a little Z pic under your nick. Cool. You are solid here.

Lots of potential in your Z. They will give you their best advice if you give them enough facts/info up front.

Thanks and welcome!

beg3yrs

Congratulations on your entry into the world of Z-cars and welcome to the forum as well.

Personally, my only motor swap has been an L26 (the 260 motor) for another L26. What I did do though, was replace the flat-top carburetors with round-top carburetors and headers. I know people who have taken the FI off of L28s and put carbs on them.

L28 (280Z) and L26 motors are pretty much drop-ins on a 240Z. There are lots of stories about doing that here on this forum and there's even a sub-forum here discussing motor swaps.

You could also consider rebuilding the current motor or dropping in a small-block V8. There are kits out there that make the change over almost a bolt-on affair.

gergstuff

I have been slowly working my way through the engine trying to get everything set the way it should be.

I put in new plugs, wires, cap, rotor, points and condenser. I was trying to set the timing last night but need to double check my efforts.

The engine seems very sluggish and doesn't have very good throttle response. It will rev but it is not what I would expect.

The flat top carburetors had been replaced with the round top version so I guess that is good. There are a lot of hoses that are plugged with screws and bolts and wires going no where maybe I can post some photos and someone can tell me if any of these hoses or wires are part of the problem.

I have been printing off sections of the manual as needed.

I still need to check compression but there is definitely a blue cloud coming out of the tail pipe.

I have a SBC ready to be assembled and it is tempting to get a conversion kit and try to drop that in there but I will stick with the original for the time being.

I need to find a device to synch the carburetors I do not imagine it would hurt to dismantle the carbs and clean them as the car has been sitting for many years.

Any thoughts about sluggish throttle response and the usual culprits?

Craig

beg3yrs

Have you checked your fuel filter? Certainly has nothing to do with blue smoke though.

Check for vacuum leaks. All those plugged hoses are likely to be smog related. Read your FSM and learn what they do and do your best to eliminate as much of that as you can!

My own personal experience with two Zs of dubious heritage was that it's likely best to strip all that stuff off, learn what it's for and replace only what you need.

I didn't notice where you're from, but here in Arizona I'm registering the car as a classic (limited driving for shows, some touring, maintenance and Sunday drives) which eliminates any smog requirements.

gergstuff

Well, I did a bit more adjusting and went for a ride very sluggish to respond to throttle under load. Got a few angry stares from neighbors (quite loud) when I got back home I checked compression, 120 psi (or less) on all cylinders. The manual indicates 171 to 185psi so I think this is one of the major reasons it lacks power.

beg3yrs

So sorry to hear that. At least you know the source of your problem.

BTW, you neighbors are just jealous.

SpeedRacer

Ever think of a SBC (Small Block Chevy)?

Check out HybridZ for more info. HybridZ

beg3yrs

That is one gorgeous engine and engine bay! I'm drooling. I'm also getting some ideas for my next project ...

gergstuff

I got my hands on a rebuilt 260 motor with dual Weber carbs that seems like it will be an easy drop in. Would like to upgrade from the old 4 speed to a 5 speed. Is there certain vintage 5 speeds that will bolt up to my new motor and ones that will not? Can some one clue me in as to what my options are?

Thanks,

Craig

88dangerdan

I have an early 260z and I just swapped in 5speed from '78 280z. That seems to be common swap and it is straight bolt up. At the same time I swap the R180 rear differential to the R200 with 3.7 gear ratio. Which I would recommend (R200). That's pretty much a straight swap also as long as you have supporting parts. The 11lb flywheel and 6 puck clutch is nice to have but not necessary for the swap.

Daniel

theramz

All the 5 speeds from '77-'83 will bolt in. The only differences are in the throwout bearing sleeve and the fork. So get them with the trans and you will be ok.

gergstuff

I have pulled the tired old motor and an working on tidying up the engine bay I need to take pictures and post to show what a mess I am making. Have already found some unpleasant surprises like old improperly repaired collision damage.

I digress...I wanted to upgrade to a 5 speed but so far the only one I have found semi-locally is $850 which seems pretty spendy to me.

I guess I will have to wait until later when I have more money to **** away, want to try and get this sucker back on the road for now.

Anyone out there within a 100 miles or so of 98248 that has a 5 speed they are tripping over and want to sell?

88dangerdan

I'm on the same coast but just over 100 miles. ..lol..Stockton, Ca. 95207 but I do have a 5speed I'd be willing to let go of.

Email me at 88dangerdan@gmail.com if interested

Thanks Daniel

gergstuff

I sure hope how I can remember how all this goes back together...