BluSkyLightning Checking in with a '74 260z, Soon to be powered by a 360

[BluSkyLightning]

So, long story short I recently bought a relatively clean 1974 260z. It already has a small block AMC v8 swap consisting of a 5.0l (304). I picked up an AMC 5.9l (360) engine that I will be rebuilding and replacing the 304 with. Here's a little cut and paste from my only other thread detailing how I got it home.

 

It was a nearly 3 hour drive each way and the car very nearly made it in one piece. I noticed that the engine was running warm, at least over 200 degrees, and stayed there. I filled it up with gas two times on the way back, on the second fill up it started up then died from vapor lock, as the fuel filter was dry as a bone. After I let it sit and cool down it fired right back up, and we were on our way again. After another 10 minutes on the highway, it ended up tossing the water pump and alternator belt. It may have been a bad or gummed up pump that was causing it to run hot, so that will be replaced very soon. I brought a buddy and a truck with me though, so we towed it back to my house the rest of the way and it's now sitting pretty in my garage.

 

I have some pictures I took this morning of the still dirty car, I haven't had a chance to wash it yet and the previous owner lived on a long gravel road. It used to be a show car in Chicago, and it came with some trophies won by that owner, as well as some shop manuals and a couple of extra headlights. Here's the pictures!

 

It is a vinyl top 260z, I didn't even know that these were made. I guess you learn something new every day. It's in very good condition all around, almost zero rust anywhere. The bottom and frame rails were undercoated by the owner in Chicago, the guy who used it as a show car. He also painted the car with it's current livery and it appears he used the car's weight in flake. It's a little too "bass boat" and not enough "bad ass" for my taste, but that will change with time.

 

 

 

 

 

 

 

 

 

 

 

 

[BluSkyLightning]

Update #1

 

Upon inspection I discovered that the original water pump on the 304 was beyond gone, so I ordered up a replacement from the local auto parts store and installed it the same day. I also put some new v-belts on there, and a new air filter just for giggles. The car ran great and stayed relatively cool, running right in the middle of the temp gauge to and from work. The problem is that it still leaks oil from the rear main seal like a sieve.

 

I did source a 360 to swap out the 304 with, and it's currently in the garage waiting on a rebuild kit. I plan to keep it relatively mild, because the engine sits so far forward it's going to be a challenge to get traction with even 300-350hp, let alone a crazy amount of power. I will be installing a hydraulic flat tappet cam, new lifters, hardened push rods, a double roller timing set, and an entire engine gasket kit. I will swap the Crane Cams ignition, Holley 600 CFM 4 barrel carb, Edelbrock Torquer intake manifold, Edelbrock valve covers, and the aftermarket distributor from the 304 onto the 360. I will also do some of the oiling mods to the engine, namely the direct oil line from the lifter valley to the back of the main bearings 4 and 5. This helps with high RPM oil starvation in the back of the engine. I will not be revving this thing to the sky, I'm looking at a 5500-6000 rpm redline, but that should be plenty.

 

List of things the car will need before I can even consider calling it done:

 

Suspension - New shocks and lowering springs, maybe coil overs if I can find a good deal on a set.

 

Wheels and tires - Don't even get me started, there are so many different choices here its killing me.

 

Flares - I love the look of them but I cannot weld, if anyone is local to the Kansas City area and has experience, hit me up and I'll bring a 30 pack and my own assistance!

 

Gauges - Speedometer is waay off, reads 90+ mph when I'm doing 70. The original tack is unresponsive, previous owner installed a mini sized one to the left of the steering wheel. I hate it. I'm either going to fix the current gauges, or possibly go with a set of SpeedHut gauges thanks to that group buy I spotted earlier.

 

Wideband AFR - I have a wideband sitting around from my last build, so I plan to install it in the Z just because.

 

Paint - The body is nice and straight, the hood needs a lot of work (can anyone say bad bondo job?), and there is some veeeery minor surface rust starting to crop up. I'm looking to paint it either gloss black, or an intense blue.

 

Interior - relatively unscathed actually, the seats and carpet are in good shape, there is a single crack in the dash , but it's all there and not too bad. I should clean it though.

 

Fuel Cell - I have a leaky gas tank. The previous owner cut it and welded it back up to make room for the dual exhaust that runs all the way back (which sounds awesome), but the tank has some seepage on the back of the tank's pinch weld and it makes my garage stink to high heaven of gasoline. I'm considering repairing the tank, or just scrapping it and moving to a fuel cell. I'm not 100% comfortable with cutting up the back of the car though. Input?

 

I washed it up, so I will post some new pictures soon.

Edited August 11, 2014 by BluSkyLightning

[rturbo 930]

I'd get a new tank and ditch the dual exhaust. I personally wouldn't put a fuel cell on anything but a track car.

 

I'd take off the vinyl roof too and make sure there's no rust underneath.

Edited August 11, 2014 by rturbo 930

[socorob]

Definitely remove the vinyl. There used to be places that would put vinyl tops on any car back in the 70s. They seemed to make roofs rust under them though.

[texis30O]

The vinyl top was an aftermarket deal....... FYI. 

[BluSkyLightning]

I heard that the vinyl roof was a dealer option, but eh, I think it would be cleaner without it.

 

I managed to snap some more pictures of it after cleaning it, not a huge difference but its something.

 

 

 

 

 

Here is the leaking gas tank

 

 

Here is the leaky rear end

 

 

 

The car does run and drive well, I have already fixed the power brakes (or the lack therof). This will be a relatively slow build, with a lot of choices yet to be made. My main goal is a fun, streetable car that is nice and clean. I will update with more progress on the 360 in the coming weeks.

Edited August 13, 2014 by BluSkyLightning

[BluSkyLightning]

I'm looking for new wheels for the car. As far as I know it is stock suspension, but I will have to get under it again to verify. I found a good deal on some 16x9 wheels, the only bad thing is that they have a +10 offset, so not a +0 like I'd like. Will I be able to run a 16x9 wheel with a +10 offset on stock suspension with spacers? I understand I might have to get some extended 240sx lug nuts to hold everything together. The tire I'm looking to run is a 225/50r16 Hankook Ventus v12, because Tire Rack is having a crazy good deal on them. Honestly, a little poke is fine by me, it'd just be a good reason to either roll my fenders or install flares.

[tooquick260]

Looks like a great project.

[BluSkyLightning]

So, I made a couple of posts to this thread with my phone, and now they are gone? Weird.

Anyways, I finally picked up some wheels and tires for the Z, a set of 16x9 CCW replicas from ebay, wrapped in Hankook Ventus Evo V12 tires. The offset of the wheels is +10, I really wish I could have found them in +0 or even negative, but I did the best that I could. The rears fit, but only just barely. I have a couple of milimeters between the spring perch and the back side of the tire. The front is a whole nother story. I have a definite issue of hitting the spring perch, so I am looking for 10mm spacers and extended lug nuts to hold everything together. I think I read on here somewhere that 240sx lug nuts fit our cars and are longer?

Anyways, here are some pictures of the wheels and tires on the back of the car, more to come when I can get the fronts mounted as well.

[BluSkyLightning]

My next main project will be to fix the leaking rear differential, is there an easy way to lower the differential to get access to all the bolts on the face of it? Or do I need to remove the differential entirely? I plan to remove the cover, replace the gasket with a new one or RTV, and refill with new fluid. I was told it is an LSD unit, and from the outside it does look like an R200, but it does not have fins on the cover. I'm not sure if that means it has different internals than stock or what. I can take some pictures of it when I get into it so we can attempt to identify it.

[BluSkyLightning]

I will be using these Dorman 610-320 wheel bolts, at 41.5mm long they should provide enough thread to keep the wheel secured with the 10mm spacers that I ordered.

[BluSkyLightning]

I finally received my 10mm spacers for the front wheels, but the problem still remains, the wheels hit the spring perches on the front suspension. Instead of attempting to return the wheel spacers, I will just be saving up for a coilover setup. Progress is moving slowly along because of my new responsibilities at work and me picking tennis back up, but hey, do what you love right? I kinda knew this car is going to take up more time and money than I originally planned, but that's a part of the beauty of doing what we do.

 

I am interested in a simple coilover that's not going to wreck my bank account, I have seen the ground control units, but I don't have the ability to fab something like that up myself, how much do shops usually charge for something like that?

 

Since I need new struts as well, I'm thinking it may be more cost effective to either buy a good used coilover set (hopefully this) or get a decently priced new set that's not a "build it yourself" type. I'm the kinda guy to set it and forget it, I'm not going to be adjusting it every week.

[BluSkyLightning]

Finally had the time to tear down the rear end, and I found several things that I wasn't expecting. It looks like the car has an open differential (previous owner lied to me, what a shocker!), and it may be on it's last leg. It looks to me like it has a lot of play in it. Everything together makes me consider my options for a new rearend. Should I just re-build this one with an LSD? Should I get a new one? Should I just weld it and call it good?

 

Oh, and on a side note, the PO had the rear end completely full of fluid, no wonder it leaked like it did, all that thick goopy fluid had nowhere to go when those gears started turning. It also appears that it may have had some water in the oil too, I saw what looked like whater beading up on the gears after I got the cover off.

[NewZed]

I finally received my 10mm spacers for the front wheels, but the problem still remains, the wheels hit the spring perches on the front suspension. Instead of attempting to return the wheel spacers, I will just be saving up for a coilover setup. 

Do you think that the spring perches will leave more room for the wheels if they're adjustable?  Have you thought this through?

[BluSkyLightning]

The main difference between the stock spring perches and a coil over setup, is the dimensions of the springs themselves. Coilovers are much narrower, thus allowing you to run a wheel with more backspacing than your stock suspension would.

[NewZed]

Makes sense.  You could probably fit narrow springs to the stock struts though, for the same purpose.  The path to adjustable coilovers didn't follow from the problem.  

[BluSkyLightning]

That's true, but I need new struts as well, and I figured that If I need something new, plus need something smaller in diameter, plus something lower than what I currently have, it all made sense to upgrade to a coilover setup. I agree that that line of thought didn't flow clearly from what I had previously written though.

[BluSkyLightning]

An update on the Z

 

I am currently rebuilding the 5.9L and prepping to swap it in favor of the 5.0. The 5.0 has had a good run, but it's starting to smoke now, and I am pretty sure that the piston rings are shot. I have the new rebuild kit already in the garage for the 5.9, as well as the shift kit and ratchet shifter, I just need to find the time between work and working on the house to actually finish it. I also got tired of looking at the busted up front valence that the car came with, so I ordered a new front air dam and installed it, plus I removed those beefy bumper guard pusher thingies from the front bumper. It's not as perfectly clean as a 240z bumper swap, but it's a LOT better than before.

Before:

 

 

After:

Edited April 19, 2015 by BluSkyLightning

[BluSkyLightning]

Next on the plate is to finish the 5.9 rebuild and swap, plus the transmission shift kit/ shifter install, then I will concentrate on the suspension and wheels/ tires.

 

Oh, I almost forgot to mention my gauges that I got from SpeedHut. They are fantastic pieces, and installed really well into the old housings, and the wiring was straight forward. My only issue is a slight one, the brights indicator is backwards. It lights up when brights are off and turns off when they are switched on. There is a solution to it, but as of right now it's just not hooked up.

 

 

 

https://youtu.be/abjiIdijiAQ

[BluSkyLightning]

Another update, I have decided that I absolutely needed to Dynamat the car. I have been driving it around now that the weather has gotten quite nice here, and my GOD is it loud. I did a ton of research about dynamat and other thermal acoustic dampeners, and discovered something quite amazing. You can buy it from Lowes. There is a manufacturer called Tite-Seal that makes an almost identical product to Dynamat ( a rubberized, self adhesive thermal acoustic insulator with aluminum on one side) at a fraction of the cost. I was able to buy two rolls measuring 9 inches wide by 33 feet long for $20 each, and it was more than enough to do the entire floor of the car. I cannot justify spending 4-5 times that ammount for a name brand, especially if it's going to be hidden under carpet its entire life anyways.

 

Here are some pictures of the process, I obviously had to remove the interior (not too hard honestly) and clean the surfaces that it would adhere to, then I went to town. Being my first time doing a project like this one, looking back I would have cut some pieces differently, but all in all I am very pleased with the way it turned out, and very happy with the results! I can hold a conversation on the phone when I'm in the car now!

 

 

 

 

 

 

 

 

 

 

 

Coilovers should be arriving today, my 5.9L internals should be done by Friday, and the current engine and tranny will be pulled this weekend!

 

The list is still long, but I have been making some great progress in a very short amount of time and I can see the light!