1982 Porsche 924 TrackBuild, Should it Stay or Should It Go?

Looking epic chap Cant wait to see this in the flesh at some point

No, it can be for change of address, taxing it, MOT, anything. Ask Mark (Blackpopracing) when they pulled the v5 for his Pop. He's currently rebuilding to BIVA regs.

its not MOT exempt until 2022

8 point rule is for radically altered vehicles, or kit cars or low volume vehicles with no type approval. it doesnt apply to someone fitting a roll cage or doing an engine swap

Anyway, to reply to a few people and try and get things back on track to chatting about cool old cars, because legal stuff's boring:




Thanks! I'm definitely not looking farward to painting the interior! Its going to be a challenge for sure.




Haha! Awesome engines, I nearly brought an LPG converted S4 as a daily a while ago, but realised it would become another project (it was modified and needed mapping) and was more than I was planning to spend, so foolishly I listened to my brain not my heart. I dread to think of the packaging and heat management nightmare trying to shoehorn one into the 924's narrowish bay would create! Certainly more power than I or the gearbox could want or need anytime soon though!




Yeah, well, expensive by my standards anyway, they're certainly not a cheap option these days. The idea of a volvo T5 crossed my mind too.

The trouble is, all this thought of engine swaps occurred before I realised how much work the car car was going to throw my way to just get it solid and roadworthy. All the suspension's junk, the brakes need rebuilding and the steering's sloppy. Given that I've got a hell of a lot of obstacles to overcome to get behind the wheel again any time soon, I don't want to bite off yet another big chunk before I've finished chewing.

I've currently got 2 original 924 engines: The one that came in the car, and one I bought cheaply off eBay, because you know... eBay happened.

The original engine ate it's camshaft in spectacular fashion, were talking about 80% of the cams lift missing on 2 lobes! Which has knackered cam followers and left some flakes of camshaft material stuck in the bearings, but otherwise it appears to have a good bottom end with healthy bores, pistons and rods, and an unmarked crank.

The eBay engine's head looks in good condition, but while the bottom end looks functional, the bores appear pretty warn out with a detectable lip at the top of them. I'll need to strip the head and check the valve guides for excessive ware, as the bottom end would suggest it's seen some mileage, but the valve gear it's self looks in good condition.

The plan will be to hone and reassemble the original block with new bearings and rings, then bolt up with eBay engines head after a little breathing work. Given that these engines owe me sod all, and I'm incapable of leaving stuff alone, I might have a go at lightening some of the ridiculously heavy internals while it's apart, I've got 2 sets after all, so I can afford to knacker some

Outside the block I'm not 100% what I'll do, it'll involve an EFI conversion for sure, as K-jet won't let me play enough. Like you say Woofwoof, an M62 would be nice, but I'd be happy with a 45 for now if I can't find a sensibly priced 62.




Thanks Mark, I'm sure you'll get plenty of chances to see it, I've been retro-less so long now I think I'll be attending just about every event I hear about for a good while after it hits the road! It'd be good to catch up with some of you past area52 guys too. I'll be at the Goodwood Weekender and the gathering this year all being well.



Sorry, I can't quite make sense of that one!

Ahh.. I think I just heard a penny drop. I was being slow!

What I'm trying to get at, is that with the introduction of the MOT exemption, I can't imagine them just assuming your car is eligible by default and leaving it up to you to tell them if it's not. It makes a lot of sense that you would still have to apply for a years 'MOT' in the same way the owner of a tax exempt car still has to apply for the tax, even though no money changes hands. Now if come 'MOT' time, you're filling in a form saying 'is the vehicle altered beyond 'whatever criteria they settle on', there's a damn good chance they're going to also ask if it's 'radically altered', and should it require an IVA test. I'm not saying they're going to, just that it seem plausible, if not likely, and I'd rather err on the side of caution until we've all seen how these rules will be applied. I'm aware it doesn't apply to my car for another 4 years or so, but I've got a feeling 2022 will come around worryingly quickly, and I see no harm in thinking ahead. (Plus there would be nothing stopping them asking the same questions on newer cars just for data collection, even if there's no MOT exemption to be had.)

Anyway, it was just a random thought, and like I say, it's not what this thread's about. If it was a real make or break factor I'd be looking into it in much more depth, but as it's just one of a few reasons to stick with the original engine for now, that's what I'll do. I can have some fun with this engine, and if it turns out to be curse word, and the new regs have all come to nothing, I may throw something more pokey in there a year or two down the line.

P.S. Thanks for the link, interesting to know.

Great project Robin
The cage is an inspiration! Great that you've tackled it all (in most) yourself.
I found dropping it through the floor a genius idea, I'd always wondered how they welded up top on a cage that couldn't be removed from the car.

I plan on doing similar with the 944 I have just purchased.

The sill repairs looked great also, again another thing I'll be needing to do.

I'll be following this closely.

I've managed to sneak out to the unit a bit over this weekend and stuck some metal back on the Porsche.

First off, just to break up all the close ups here's an overview with the cage in place:



As mentioned in my last post, the bulkhead's now closed up around the cage:



And most of the cage inside has got primer on it:




So onto this weekend's work. The rear axle mounts have been missing for a long while. I originally cut them off to repair the area around them, but the mounts themselves were far from healthy:



I hadn't bothered replacing them because I knew that the cage would be coming through the floor into the bottom of them, so now with the cage done, it was time to make up some new ones. As I mentioned earlier in the thread, I'd marked their position on the floor-pan for future reference, and the marks that located them side to side were very useful, but the ones that did the fore-aft position were on metal that I'd since replaced. Woops! A little wrestling and an engine crane got the axle rested back on the upside-down shell lined up with it's other mounting points so I could mark the correct position for the new mounts. I forgot to take any pictures though as I'd forgotten my bluetooth speaker, so my phone was in the corner plugged into the stereo.

First up I cut a plate to the width of the axle bush, and the height/shape to fit to the inside of the sill, stuck a 2" hole saw through it then welded through the hole to the sill, creating a spreader plate that also acted to locate the axle mounts. Next up I cut out the new mounts them selves, which could be welded to the ends of the spreader plate. Although I won't be using the factory axle, I wanted to keep the mounts as per the factory to keep future options open, so I copied what was left of the original ones.

Spreader plate and the forward plate of the mount welded in:



Then the rear plate made up and welded in, along with a gusset tying it into the cage spreader plate and a return lip for the forward plate:



All seam welded up. It's not going to hurt to have the mounts beefed up a bit as with firmer, solid mounted suspension they'll be taking more of a pounding than they did originally.





While I was in that area, I also cleaned back the other rear axle mounts and shock mount, which had some surface rust on them, then threw some kurust on it all for good measure:




Quite excitingly, once I've copied this mount onto the other side the shells metalwork will kind of be 'finished', by which I mean if I was so inclined, I could just throw paint at it and bolt the car back together with all the original parts. That's not quite the plan though!

Well, There's been zero real world progress since my last post, mostly because I wasn't going to get a RWD car with summer tyres through 9 miles of country roads in this!



(The furthest I managed was some sideways fun in an empty industrial estate or two before it got too deep )

Having had some more time stuck at home than usual, I did however manage some virtual-world progress:



I need to double check some dimensions and order the Gaz Gold coilovers, but this has got me much closer to being able to order up the parts to make the new rear beam. Hopefully Gaz will be ok with giving me the external dimensions of the coilovers so I can get the parts ordered before they arrive.

Geometry wise I've kept the original pivot angle when viewed in plan (~15 degrees), but replaced the torsion bars and rubber bushes with a pair of 3/4" rose joints, moved up and farward as much as possible to minimise the effect of lowering the car. I've also tweaked the inner pivot down slightly, to get the toe change inherent to semi-trailing arm designs back on my side.

If you're not familiar with them, semi-trailing arms give toe in when moving the arm away from being horizontal (pivot points at the same height as the wheel centre). This is generally a good thing if the arm's horizontal at ride height, as a little toe-in will aid in stability and can help get the best out of the tyres slip angles. The trouble is, when you lower them you end up with suspension that toes in on compression, but toes out on extension, which can make for some undesirable lift-off oversteer. Luckily moving the pivot angle when viewed from the front/rear can play with the point where the change in toe reverses, so even though space constraints mean I can't run the arms horizontal at a height I'd be happy with, I can have my cake and eat it with a low ride height and toe change that's back in the situation Porsche intended; both compression and extension causing toe-in. Hopefully this will keep things nice and predictable and stable. I've designed in some adjustment of the inner pivot height, so I can tweak it to suit a range of ride heights. This adjustment is surprisingly sensitive, so although it looks like a good place to use for camber adjustment, I'll actually be making camber (and toe) adjustments by shimming where the bearing carrier bolts to the trailing arm.

Otherwise it's just a bunch of tubes and laser-cut plate to stick the wheels on. I'm intending to use mk4 golf hubs, bearings and CV-joints. Mostly because I've got some new ones lying around. The hubs will be re-drilled to take studs at a 4x100 PCD, and have the spigots turned down to 54.1mm to suit the MX5 wheels I have.

I'll have to make drive shafts out of the Mk4 ones I have (and maybe the porsche's inner sections, I haven't checked if the gearbox flange sizes match yet). They're tubular shafts, so I can cut them, sleeve them and weld them back up at the right length.

The brakes will be Audi S3 calipers on mk2/3 front disks. The calipers are aluminium and made to work on 20mm thick vented disks, with a built in handbrake mechanism, so keep things light and simple.

Hopefully this lot will come together to make a set-up that's lighter, more adjustable and easier to work on than the factory stuff, while letting me run the car low without ruining the handling. The switch from rubber bushes to rose joints should tighten things up somewhat too (at the expence of some road noise I'm sure, but comfort's not really what I'm building this car for.)