Beta Spider 2000 engine rebuild/refurb

[mangocrazy]

Yesterday I got the call from Stanwood Engineering that my block and sundry engine parts had been through the hot wash and ultrasonic cleaning, and the block had been bored to suit my 84.4mm pistons, without the need of any special chicanery; there was enough meat on the standard bores to do a straight, clean rebore and flex-hone.

So in order, we have:

Various bits and pieces in boxes and trays as picked up from Stanwood:

A couple of views of the block; firstly from above, showing off the deck facing I'd asked them to do, and then from the side, with the flex-honing marks clearly visible. Given the state of the block when they received it, it's scrubbed up particularly well:

When I first arrived, Jonathan told me he had some good news (the block rebored without any issues) and some bad news. The bad news was that both sets of camshafts I'd taken in to them had reacted adversely, and in a way that they'd never seen before, to the ultrasonic cleaning process. The standard cams had shown the worst reaction;below is a photo of the base circle on one of the OE cams. The other OE cam was only marginally better.

It also emerged that the 'Kent cams' that I'd bought secondhand and thought were billets were in fact re-grinds. These weren't quite as badly as affected as the OE ones, but still showed a fair amount of marking. Had I inspected them closer I should have noticed 'FIAT' stamped into the shafts, but it's far easier to see now than when they were dark brown and with a film of oil on them. The surface markings aren't as bad as on the OE cams, but still don't augur well:

Jonathan was very apologetic about it and without any prompting offered me £50 +VAT off the overall price, which was welcome. I can't see how ultrasonic cleaning could have caused such a reaction unless there was some underlying prior issue with the cams. It's a process that is ubiquitous in the automotive industry.

After thinking about it a while, I gave Kent cams a ring and told them my story. They said that it may well be possible to do a very light grind on the lobe faces, taking off around 10 thou to clean up the faces. I'm going to send both sets down to them for their inspection and will probably be guided by their recommendations, unless anyone here has an opinion to the contrary.

Every other component, including the auxiliary shaft, came out just fine. It was just the camshafts that had the adverse reaction. Very odd. I'm not sure whether I should start looking for another set of cams or whether to wait until Kent have given their opinion.

[Neil-yaj396]

Did the cams need the full clean? Even if not I, like you, wouldn't have expected such a severe reaction.

[mangocrazy]

Probably not, but it seemed like a sensible move at the time to add them to the other parts that really did need the clean/ultrasonic bath. I was wondering what people's view of cam regrinds were. Are they as awful as GC makes out, or is he simply following his normal doctrine of perfection? I've no desire to build this engine with a substandard or flawed part, but if it's just a question of using thicker shims to compensate for the reduced base circle, I'm not sure what the problem is.

[WestonE]

Hi Graham

Sadly I think your cams are scrap and a light skim would not give a good hardened surface. I would not want to risk it. For information (far too late) with cams scotch bright and brake cleaner is normally enough with sometimes 400 the 800 grade dressing where there is oil seal rub.

I have some Bayless cams that might do the job for you, but this might be the point to source another Beta 2000 standard exhaust cam and a GC 3A inlet cam along with GC Vernier cam wheels. If in doubt send GC your cam boxes with the exhaust cam and have him dial in the cam timing for you, unless you really understand this and have the dial gauge protractors and set up plates. Precision timing really can make your engine fly and the CG 3A standard exhaust is a good mix for around 170BHP with 150 FtLbs and revs low enough not to need forged pistons.
PS make sure TDC is perfect when you build the engine and very clearly and precisely marked i.e. not using the cam belt cover.

Good luck

Eric 

[mangocrazy]

Yes Eric, I think they are probably scrap as well. Isn't the GC3A cam getting slightly overkill for my engine? I really want a good torquey, tractable motor that doesn't need to be red-lined to get maximum effect. It will be spending most of its life in the 2000-6000 rpm range with an occasional foray past 6k. I'm aiming for around 155-160 bhp with a broad spread of usable power. And what kind of spec are your Bayless cams? I'll be using the Vernier cam wheels I bought from you many moons ago - they're currently away having the purple anodising replaced with something less lurid.

[rossocorsa]

I might have a strada 130 exhaust cam and also a standard IE inlet/exhaust, finding time to dig them out might be another question though 😂 let me know if you are
interested and I'll see what I can do

[mangocrazy]

Hi rossocorsa, I'd definitely be interested in a pair of IE cams, as it was always my intention to use the standard cams as a fallback position if the Kent cams weren't up to snuff. Is the Strada 130 exhaust cam regarded as a performance booster? If so, I may well be up for that as well. I'm not in a tearing hurry as the bottom end probably won't be rebuilt until May/June at the earliest, but I would like to secure the parts I will need in the future.

[rossocorsa]

I'm using the 130 inlet on my VX not using the exhaust cam as that would be a bit OTT with a blower. It is higher lift and slightly wilder than a standard cam. I'll try to have a look for them but in don't have much time at the moment so remind me if I don't get back to you within a couple of weeks.

[mangocrazy]

OK, no problems. I'm in no rush, just trying to make sense of this setback, really. Thanks for the offer - much appreciated.

[WestonE]

Hi Graham

The 3A inlet standard 2000 exhaust cam combination is a nice one for a broad spread of torque and keeping the revs well within the cast piston 7200 RPM rev limit. Not a peaky narrow power band and a common conversion for Monte engine re-builds on road cars using 10:1 or higher compression ratio and a gas flowed head.

If you fit a pair of 3As then you will potentially see more power i.e. up to 200BHP but that peak power will be somewhere like 7700 rpm with a rev limit at 8500. That would break cast pistons!

A Strada 130TC cam has 0.5mm more lift but less duration so not much different than a standard Beta or Monte 2000 exhaust cam for your needs.

Eric     

[mangocrazy]

Hi Eric,

Thanks for that; I don't think I'll be going down the inlet/exhaust GC 3A route...! But a 3A inlet/2000 exhaust does sound interesting. Whatever happens I will want a pair of standard 2000 cams as a base setting, I think.

I meant to ask you further about comments you made in an earlier post:

If in doubt send GC your cam boxes with the exhaust cam and have him dial in the cam timing for you, unless you really understand this and have the dial gauge protractors and set up plates. Precision timing really can make your engine fly


So GC will only need my cam box(es) to set up the cam timing? I'd like to give GC the top end and get him to build it up complete, but I don't know if I can afford the bill. I think I need to read and re-read the sections in Guy's books regarding rebuilding the top end.

PS make sure TDC is perfect when you build the engine and very clearly and precisely marked i.e. not using the cam belt cover.


I've got a dial gauge with spark plug inserts to ascertain TDC. Will that be sufficient?

[mangocrazy]

I had a chat with GC a few days ago and he mentioned that the limiting factor on whether I could run the 3A inlet/OE exhaust cam setup will be the depth of the valve reliefs on my Vick Auto 10:1 (allegedly) pistons, as the 3A cams have considerably more lift than OE. I foresee a lot of dry-building going on before even the bottom end is finally rebuilt. GC said that you need a minimum of 2mm piston crown to valve clearance and preferably more, so this is something I will need to be certain and get right.

In other news, I've received my sump pan back from blasting and had the BetaBoyz sump baffle kit welded in. After these photos were taken I decided to get another couple of tacks welded in, one in the middle of the 'short' near side and another on the long rear side of the sump. Everything looks and feels good and solid now.

The only thing that concerns me a little is the degree of corrosion and pitting on the front face (presumably where it's been peppered by stone chips). Does this look like the thickness of the steel has been adversely affected?

I'm toying with the idea of treating the spots of flash rust that have developed since blasting (in spite of being kept in a warm, dry environment) and then skimming the front face of the pan with some JB Weld or similar epoxy resin before priming and painting. Does this sound a good idea or am I over-thinking it all?

[rossocorsa]

I presume you've done a trial fit on the sump? I found out a pain in the proverbial to fit in the vx a lot of fiddly adjustments to get it near right. I can't see a problem with filling the sump exterior is the only way to get a really nice finish.

[mangocrazy]

No, the trial fit will come when I get the block back on my engine stand. I'm not expecting it to exactly fly back on... Before I do that I'll be looking for some stainless M6 studs to Loctite to the block, rather than using bolts. Then I can use nyloc nuts to fasten the sump to the block and be as sure as I can be that nothing will vibrate loose.

But I'm sure the bead blasting and welding will have distorted the sump to a degree that it will be a pain to fit.

[rossocorsa]

Studs are definitely the way to go but of course they make fitting the sump in situ more awkward, easy whilst on a stand. The baffle kit might interfere with the oil pump and/or the return pipe, I'd recommend trial fitting before you go much further.

[mangocrazy]

GC is currently refurbishing the oil pump and doing his thing with my crankshaft, so when all that comes back I'll give it a trial fit. I'm in no rush and want to make sure everything is correct. Probably best to do the trial fit before I start any cosmetic filling, as if the sump needs some (ahem) encouragement that could cause any filler to drop off.

[WestonE]

Hi Graham

I agree on the trial fit before finishing paintwork filling the outer sump surface and painting is cosmetic, just be VERY careful to clean the sump internally before fitting finally. I found the sump easier to fit with studs.

Every Beta should have a sump like this the original is hopeless even for enjoying corners on the road.

Eric   

[mangocrazy]

I've a number of threads referring to the (extremely slow) progress on my Beta Spider, but this has the most information so I'll carry on with this one.

The engine block has been painted and the bare bottom end (crank, rods, pistons) has been assembled by Stanwood Engineering and the short engine has been sat on an engine stand for best part of 6 months. My initial plan was to hand the short block, plus the modified head I bought from Eric ages ago, along with all the other bits and pieces (cams, camwheels etc, etc.) to Guy Croft for him to complete that part of the build.

When I rang Guy he politely but firmly informed me that he would not be pepared to assemble and dial in a cylinder head that had been fettled by another tuner (in this case the late Barry Waterhouse of Evo Engineering). This left me in something of a quandary, and the only way out seemed to be to repatriate the original cylinder head from the engine that suffered a major mishap in France and get Guy to use that, as I know that head is bog standard and as it left the factory.

I brought the head back with me from France last weekend and duly set about cleaning it up and removing the valves. Below are photos top and bottom of the manky thing as it arrived back from France. And once I'd removed the valves, the true extent of the damage wreaked by the French garagiste became painfully clear. Only one valve, possibly two, survived unscathed:

I then set about the head with a can of Jizer and a brush, followed up by lots of hot, soapy water. After that I removed as much of the remains of the old head gasket as I could. It certainly looks a lot less manky now, even if it's a long way from Guy's expected standards of cleanliness:

The next step is to take the head and the pieces of valve train that will be re-used (collets, top and bottom valve caps) to a local firm that specialises in vapour blasting. After that I'll run a tap through all the threads and de-burr where appropriate, by which time it should be in a fit state for Guy to work his magic.

[betabuoy]

Hi Graham,
Given that you appear to need new valves anyway, are you going to ask Guy to put in larger seats for the inlets?
Chris

[mangocrazy]

Hi Chris,

I did think about that, but have decided to go with standard valve sizes, inlet and exhaust. Cost is definitely a consideration here. Last night I ordered a set of Vick Auto inlet & exhaust valves, along with valve guides and had them sent to a friend who lives in Idaho. He'll ship them to me as a 'gift', hopefully avoiding the steep import duty most items from the US attracts. The whole lot came to 92 dollars (plus 15 dollars shipping within US) and are available off the shelf, so quite a saving.

I'm not aiming for such a lofty target bhp-wise as you. I'll be very happy with 150-155 bhp as long I have good drivability and torque. I'll be using standard cams, Vick Auto 10:1 (allegedly) pistons and DCOE 45 Webers with 36mm chokes and GC offset manifold. I'll get Guy to gas-flow and do his stuff on the head to suit the pistons and also do the top end build and cam timing. The car has a 4-2-1 exhaust fitted already, but the other improvements should help realise its potential (hopefully). I've also acquired an MSD ignition box with matching coil, which I'm hoping will further improve drivability, starting and low speed running.

Just don't ask me when it will all be finished!