The Z31 Project - Race Car

[260DET]

A problem to be solved before going further with the Powerglide Gear Vendors combo, the GV shifts electronically, the glide mechanically. Apparently it's possible to convert the glide's valve body to electronic shift but the US supplier won't talk to me, it should not be that difficult though if I can get hold of the right bloke here, need engine braking too. If that can be done then the next thing is to get a electronic setup for driver controlled shifts, probably going to go with a paddle shift arrangement rather than a floor bump shift like the 280ZX has. Have found a promising device that is primarily for driver controlled shifting rather than the usual more expensive devices which are multifunctional.

 

All the above is so that shifting is made to be as simple as possible with an OE type mechanical shifter on the floor for PNR only. All this to save 50kg and reduce parasitic loss but if it all works properly then it's going to be a damn good setup for circuit racing.

[260DET]

Whoohoo, I'm excited   The left side rear suspension is complete, a bit more welding etc but it's bolted in with all the angles and dimensions from the chosen suspension programme setup in place and correct. So now the car can be rolled over to get access to the right side so it can be done.

 

Of course there are pics, two pics which I hope are self explanatory but note that the two lateral control arms are shiny aluminium and that there is a mutual supporting (blue) brace going from the upper inner pivot to the lower inner at the bottom of the diff, static roll centre is right there too but it's invisible 

 

Edited April 29, 2017 by 260DET

[CBR Jeff]

Richard I am looking forward to seeing how this works out.

 

Jeff

[260DET]

It's hard to believe but after all the calculating, all the design work, all the fabrication it looks like the diff and suspension is ready to be fitted permanently, except that the springs have not arrived yet. So the diff has been mounted including a last minute addition, a torque arm. Two reasons for that, firstly to help accomodate the extra load from two lateral suspension arm pivot brackets, secondly to take load off the diff cover which can crack. Pic shows pretty well everything except the front bearing lube mod which is hidden inside the front diff mount.

 

[260DET]

Koya 18x10 wheels arrived, nondescript black but it's a pleasant change to get something that bolts straight on without requiring any attention.

 

 

 

 

[C.A.R.]

 

I thought you weren't allowed to drink liquids after 4pm?

[dat2kman]

 

I thought you weren't allowed to drink liquids after 4pm?

"Nil by mouth" is what the nurses write.

[260DET]

lol coincidentally I was thinking that a can would look better but they are/were all full, as in full of liquid and full strength.

[260DET]

Oh and Lurch/Chook, I was once young and smart arse too, now I'm still a smart arse but one who knows more.

[260DET]

Moving right along from the chit chat, one side of the rear suspension is all bolted up and best of all looks like it will be a goer. By that I mean that the various specs like toe, camber, ride height and track look to be within adjustment and axle range which is a hell of a relief with a suspension dimensioned using tools like a tape, ruler, level and so on found in your average diy workshop. Pics should be self explanatory, note cool green coilovers with yellow King springs, the 10" wide wheels fit in easy as, about flush with the outer guard. Could fit 11" wides in there but with 275 wide semis the widest available there is no point.

 

 

 

EDIT: Six rod ends each side, total of 12 including one at the bottom of each coilover which was converted from rubber bush type. All cro-mo, not that expensive if you shop around.

Edited June 8, 2017 by 260DET

[260DET]

Have collected some more stuff, pics below, the two main Shift parts are an electric transmission shifting mechanism which on command changes the Powerglide in to R or 1 or P or whatever and the controller which is push button as delivered but which will be modified to change in to 1 and 2 by a lever operated switch of some sort. The other bits are adjustable front wheel bearing spacers, no shims or turning on a lathe required. The instructions require the adjustment to be done using dry bearings with a touch of preload 

 

 

 

[dat2kman]

One piece, somewhat more substantial, larger shoulder dimensions, greater load bearing capability.

Couple of hours to knock up, and then fit with correct preload, using a lathe.

[Cozza]

Hey Richard, those bearing spacers look interesting. Can you post a link to the supplier please.

[260DET]

Wheel spacer source here http://store.drpperformance.com/bearing-spacer-legends-front-adjustable-steel/

[Cozza]

They look good. Still a bit of messing around to fit but seeem to be reusable if/when you replace your bearings. Do you have to get them to suit the specific stub axle? Website seems to be "1 size fits all"?

[260DET]

The linked Legends spacer is the one I have and also apparently fits the S30. Scroll down to see the video which shows adjustment procedure, adjusting the bearings dry (without grease) makes sense and will improve rigidity compared with using greased bearings. As I've said before, using the factory adjustment procedure is obviously not the best way for a race car where you want to keep those front wheels from flexing around the bearings when cornering.

[260DET]

Front struts and wheel bearing hubs have been done with new seals, bearings and spacers. The spacers had to be adjusted, see previous posts, but that was no problem, the seals did add a lot of drag though so there may be something to be gained in using low drag seals. Build is moving slowly lately, a lot of little things and interruptions. Pic of one strut below, note the race spec holes and the gusset across from the strut to the axle body.

 

[260DET]

Fuel system is done at last and it's a bit different to the usual race car setup. The cell is partly filled with foam which sits on top of a silly expensive Holley fuel mat, from there fuel runs by gravity to the EFI pump and from there to the engine bay fuel filter via a new aluminium fuel line. The pump outlet is T pieced to a pressure regulator which returns excess fuel to the tank. And that's it. In the pic, fuel cell at the extreme left, pressure regulator on the extreme right with the braided return hose running along the top back to the fuel cell. Really needs a close up pic of the EFI pump and regulator too (edit: done)

 

So now the car can come off the rotisserie, yay, another mile stone.

Edited July 18, 2017 by 260DET

[PZG302]

Why only partial fill of the tank with foam???

 

I would have filled all the tank as a safety thing. Especially after I had a fairly big shunt at Oran Park where the fuel tank was ripped from the mounts, and even with a full tank of fuel foam a few litres were still sprayed over the back of the car as the filler neck was ripped from the tank. Having the foam in the tank in that crash certainly prevented a much worse incident from happening.

[260DET]

With this car the cell is well forward and central so it's going to take a big crash to reach it, filling the tank with foam would have been better but it does have roll over valves on both the vent and filler. It's a hell of a lot safer setup compared with the stock tank in the 280ZX plus all the extra fuel lines required with a swirl pot, pickup pump and return fuel system. And the fuel mat acts as a filter so the only real filter it needs is one EFI filter in the engine bay.

Edited July 20, 2017 by 260DET

[PZG302]

I still would have thrown the extra half dozen blocks in.

 

Even though I am using the standard tank in the S14 in front of the rear axle and below the floor, again a monster hit to get that far, I will still be filling it with foam. I just don't like the idea of free spilling fuel about in a big hit.

 

Maybe I'm a little paranoid after a couple of decent hits and my time as a firey putting out some mighty big fires over the years, including Darren Pate's sports sedan that went in backawards after the kink at lakeside and split the fuel cell in front of the rear axle, and a few nasty fires at Bathurst in a variety of cars.

[260DET]

You are right Matt, there is no real reason why the tank was not filled with foam, it's just something that I didn't think of doing. Funny thing is while I'm not a particularly brave driver safety is not a big priority or concern, wrecking the car is though.

Edited July 22, 2017 by 260DET

[260DET]

It's always nice when you reach the stage of bolting prepared parts back onto the car, feels like progress is being made instead of attending to an almost endless list of jobs. So the structural part of the modified front end has been bolted in as the pic below shows, very pleased with the additional bracing which involved a lot of work but not much weight. Additional attachment points were welded to the chassis which gave a lot of design freedom. New hollow front ARB is in but the supplied arms have to be lightened so pics of the front suspension when that is done, next job is to refit the electric steering unit and sort the shaft and it's support out.

 

 

 

[260DET]

Ripper tune!!!! Have fitted up and adjusted one side of the rear suspension and axle and it all looks great. Pivots smoothly, nothing gets in the way, eyeball of toe and camber look ball park, axle CV's have end space in and out, everything is adjustable including droop independently of the springs which can be adjusted separately. With the right facilities it could be made lighter again but it's certainly lighter than the original semi trailing arm setup with a lot better geometry and no rubber bushes. Descriptively it's a trailing arm with lateral links type used in some BMW's and a Bluebird race car that I know of. Wonky pics show full droop, static ride height will ideally have the long lower link parallel to the tarmac.

 

[260DET]

Finally got the custom roll centre spacers so some progress with the front end, the car is about ready to drop down on it's wheels now. Once that's done more progress on the body can be made eg extra spot welds around the windscreen, door and side window openings. But fiberglass work has started too seeing that things are warming up a bit, don't want to doing it in the middle of summer. Obligatory pic.