Stock Car Mafia's '78 280z LS2 Build

[bramagedained]

Ha!  Hopefully I can bring some valuable information to the table for you so you can avoid all the mistakes and pains I had to go through!  What year car, engine, and drivetrain do you plan on going with?  I've been told to go to some of the ZOOM meets but I probably will get blasted by the purists!

 

Early 74 260.  It has a SBC/TH350 in it now.  I'm hopefully going to throw in a 4.8/5.3(keeping the TH350) later this winter and leave it N/A for the coming summer.  Next winter will be turbo and either a TH400 or glide.

 

I'm in the middle of the 8.8 IRS swap right now.  That along with wheels/tires, front brakes, and flares are my priorities for this winter.

[Stock Car Mafia]

Those 5.3 turbo builds are something that still interests me.  Man, that thing will be sweet when you are done!

[Stock Car Mafia]

Last night I was able to do a quick few things before it got too late.

 

I replaced the torn tranny output shaft seal.  I didn't get the GM one with the rubber boot on it and feel this should be sufficient (National Oil Seals #4583).  I popped the old one out with a screw driver, cleaned up the surface with some IPA, laid some RTV sealant on the new seal, and tapped it in with a rubber mallet.

 

 

 

 

I also measured the serpentine belt with some minty fresh dental floss.  I figured it would have to be close to 54 1/2" or a size bigger.  The Gate's belt #K060551 fit the best out of the bunch (55 3/4") but the tensioner is not full loaded and may grab the 55 1/4" belt today and see if that fits better (Gates #K060547).  With the belt on I found 2 things that will need to be addressed that have popped up other places on the forums.  

 

1.  The idler pulley will need to be switched to a 6 rib pulley.  I do not feel confident this will keep the belt on the water pump and I don't want to worry.  When I return a couple radiator hoses today at Advance Auto I will be picking up the Dayco pulley (Advance #89015)

 

 

2. The belt comes in contact with the lower alternator mounting bolt.  I don't know the best solutions to this yet, but I may try to drill out the mount a bit and see if I can get the bolt to recess a little bit.  

 

[Stock Car Mafia]

I spent a little time dropping the fuel cell in the car to get a visual and a couple measurements for my mount.  I ended up cutting the floor more than just the spare tire well to make room for it without affecting many of the rubber grommets in the floor.  

 

 

These 3 frame brackets will be cut off and ground smooth to give it a cleaner, less hack job, of a look.  

 

 

 

 

I needed to get a visual of the tank in the back as I don't want it hanging down too low, but enough to see the sump  The vent tube and return line will need angled -AN fittings on them, so there needs to be clearance there.  I plan on sealing up the floor so me and the passenger are isolated from the tank.  The 180 deg. -AN fittings I got will not clear the side of the tank, so I will swap them for 150 deg. fittings.  

 

 

This may be close to where the tank sits:

 

 

 

As for the mount, I am going to use the Jeg's straps that work with the tank (since there are not welded tabs on the tank).  I will build a square frame out of 1" square tubing that the straps will mount to.  I will have tubing welded to the frame that will run the width of the frame and bolt to 4 90 deg. tabs on the frame.  This will allow me to drop the tank by unthreading the fuel lines and unbolting 4 bolts.  I am still mulling over the exact design and just measuring and measuring more before I start cutting.  

Edited January 9, 2016 by Stock Car Mafia

[Stock Car Mafia]

I also have my fingers crossed on a functional 3.71 CLSD R200 longnose that is coming my way!  I was able to get both turbo axles with it as well. 

[Stock Car Mafia]

With all the errands that needed to be run today right before xmas, I only got a little less than an hour tonight to play around.  

 

I ended up getting the ribbed idler pulley from O'Reilly's (Gate's 38008).  This is a 70mm pulley compared to the 76mm smooth pulley.  This made me opt for the shorter Gate's #K060547 belt.  It turns out this was a safe bet.  

 

 

 

I went ahead and started cutting my lower radiator hoses.  I do not remember which hose p/n's as I just matched them up to my coat hangers.  

 

 

Cut the hoses, threw in a 1 1/2" coupler, and put both hoses on the car before tighening the clamps.  I'm happy with the results, but may clean it up later if I can find ONE hose.

 

 

[Stock Car Mafia]

Well, I've been away for a while.  My close family and I went on a 4 day vacation retreat up to Larsmont, MN and rented a cabin.  It was a good time away and gave me some time to sit in front of the computer to do some reading to prepare for more work.  

 

My initial plan was to use 1" square tubing to tie both "frame" rails together and use the Jeg's mounting kit to hold the tank in place.  To me it just didn't seem very safe or secure for a tank loaded full of fuel.  I ended up drawing a full cage for the frame and decided to execute on it.  

 

 

 

 

Everything was tacked up and I wanted to test fit.  The tank is 10" deep so I cut my vertical sections at 10".  I didn't take in to consideration the 1 inch on each side and the tank sat high in the enclosure.  To me it wasn't aesthetically appealing so I ground down the welds, made my cuts, and welded it back up.  Closer but much better.

 

 

 

We worked on centering the Jeg's straps and drilling holes on each side.  The top straps ended up being longer than needed so the holes had to be elongated.  To be honest after drilling the holes larger for bigger bolts, elongating the holes, and grinding down the burrs, I would have much rather bought metal and bent it myself.  

 

 

A buddy mentioned to me some have used the Armacell R-1 Foam Insulation Tape (#TAP18230) as insulation for the tank straps.  30 feet will go along ways but it ended up working great!  

 

 

 

 

With adding the frame, I lost quite a bit of room for the exhaust.  When the kit gets here I will play around with the bends to see if I can manage to fanagle it by.  I think I got the kit with the lowest bend radius (4") so I may be ok.  I still am not sure where the angle iron tabs will end up or how to isolate the tank from the coupe portion.

 

 

 

 

I am going to be grinding down most of the welds as there are some pretty nasty goobers on some spots, but then I can sand, prime and paint it once it is put together for good.  I will leave you with one package that came today.  I think I got pretty lucky on finding what's inside 

 

Edited August 12, 2016 by Stock Car Mafia

[Stock Car Mafia]

I forgot to mention I ended up getting a decent tan from welding.  Note to self:  Wear a sweatshirt next time.

Edited December 29, 2015 by Stock Car Mafia

[RebekahsZ]

I would go ahead and pull the tank up higher into the trunk to preserve some ground clearance. You gotta have an empty trunk at the race track anyway. Consider adding a tow hitch or parachute mount at this point. Never say never. You are at a effect point to add those things and you already have the welder out.

[Stock Car Mafia]

If I were to raise the tank in to the trunk, what is the best way to isolate it from me the driver?  I don't plan on drag racing at this point so a tow hitch and chute would be over kill.  The welder however is always in reach!  

 

Right now I am not going to cut or weld until I can brainstorm a little more and get my exhaust kit in.  Clutch and flywheel, harness, and ceramic coated headers will be coming today.  The driveshaft will be here tomorrow.  Clutch MC, line, and bleeder will be here in a couple days.  I borrowed a compression tester from my brother's fiance.  Ya she's a total badass car techy like me 

 

The topic of paint has been flying around as of late.  It's hard not to think about it.  After I determine this motor is alive and well, I will work on sectioning my struts for coilovers, getting a set of flares, buying wheels n' tires to set the ride height.  

Edited December 29, 2015 by Stock Car Mafia

[Stock Car Mafia]

I thought there was an intake tubing kit that either JCI or Jags that run had put together?  I'm spending too much time time to find it and maybe someone could point me to the right direction for intake tubing?  I could custom build one from siliconeintakes, but right now, I'd rather just have a bolt in kit.

[RebekahsZ]

There's no bolt-in kit, you gotta cobble something together.  But, to get your build done, you could just put an air filter on your throttle body-cold air is a bit over-rated.  In terms of isolating the tank, you really don't have to isolate it unless you are building to a rule book that requires it to be isolated.  Just use a vent line and a non-vented cap.  Almost everybody has vent lines and a fill tube passing thru the interior back there.

[Stock Car Mafia]

Thank man, here I thought there was.  I just need to suck it up and piece one together, it isn't that complicated.  I have my measurements for it all.

 

I haven't read any rulebooks yet, it just sounded like a good idea for the tank  

[Stock Car Mafia]

Here is the surprise.  I picked up a Z31T CLSD with 3.70 gears and a pair of axles to go along with it.  I am still waiting to hear back from the seller, jyz77, if the bearing caps were put back in on the proper spots.  The diff was apart before it was shipped.  

 

 

I picked up the last set of 6 clutches that Savage42 had for sale, just in case I need those down the road.  Does anyone know where you can get a rebuild kit for this diff?  I want to source out the races, bearings, seals, and shims in case I do need a rebuild.  

 

The stage 3 clutch, 18 lb. flywheel, and slave cylinder came in as well! 

 

 

The wiring harness also came in.  A relay for the fuel pump is wired in but no relay for the switched ignition or 2 fans.  Looking at how the harness sits in the car, I am almost positive I will end up puttin the computer where the old EFI computer from the L28 was.  This way I can utilize the hole that is already in the firewall and will still be able to use the stock plastic cover.  I will have to dremel it out for the 3 harness plugs however.

 

 

 

 

I just realized too, when plugging everything in that the reverse light switch will not fit without pounding out the trans tunnel more.  Is there possibly a 90 deg. plug that will work here instead of the straight plug I have?

 

Edited January 30, 2016 by Stock Car Mafia

[Stock Car Mafia]

I took out the original gas pedal as well.  I am going to get some steel plating (don't know what size gauge yet) and will mount this to the 3 stock screws and then mount the LS2 pedal to the plate.  

[RebekahsZ]

Look for a Mustang T56 reverse light switch. It has a 90-degree plug. Hard to find. I haven't rebuilt any of my diffs. If they feel smooth, I run 'em.

Edited December 30, 2015 by RebekahsZ

[Stock Car Mafia]

This is the reverse light switch part number I am starting at and will keep reading to see if it is right:

 

1R3Z-15520-AA

[Stock Car Mafia]

Well I will have to say, this is the first time with the project that I am getting pretty F%*king flustered.  The damn driveshaft slip yoke will barely go on maybe 1/2" before binding and not going on any further.  I can't even get it to the oil seal!  There is enough room to rotate the driveshaft so I am getting it lined up straight before sliding on.  It just seems like it is a little too tight.  How in the hell do you clean off the output shaft or the splined portion of the slip yoke to make it fit?  I feel this should be pretty damn straight forward unless I'm a total fool.

[Stock Car Mafia]

Well I ended up taking the motor out for tomorrow.  The bottom of the alternator, motor crossmember, and steering rack bracket/clamps all need to be clearanced to make more wiggle room for when the motor twists.  The trans tunnel will be banged on more and the flywheel and clutch, new pilot bearing, and bleeder/clutch lines will be going in.  I was going to paint the oil pan but am going to leave it bare, so I will RTV seal the oil pan gasket and retorque that.

 

On the other hand, this gave me more room to dick around with the slip yoke.  I am pretty damn sure the dirty b*%ch is oblong and doesn't want to slide on nice.  I forced it on probably an inch or more with a mallet and wacked it back off.  On the inside of the yoke about 5 or 6 splines are shiney which tells me the yoke splines are too tall.  Any way to remedy this?

Edited January 9, 2016 by Stock Car Mafia

[Stock Car Mafia]

I spent most of yesterday dropping the motor xmember, cutting and tacking in some 1/8" plating, and putting it back in to check the gap, and then taking it back out again to weld it up.  Overall it wasn't that complicated and I believe my welding has improved.  

 

 

 

Underback side of the passenger side.

 

 

Underback side of the driver side.  I ended up grinding more on this side before tacking in the side pieces.