So after my last thread about building a 1776 engine I have thought about it all and re-read all the posts and taken on board all the information and advice concerning the problems with stroker and high capacity engines. I am therefore going to just go for a simple 1776 build. Can you just give me a basic walk through of the specification I should be looking at and the suggested work that needs doing. I am hoping to re-use as much of my existing parts as possible. I have an engine with a damaged case with all parts available for the 1776 to use so I can leave the fitted 1600 engine till the 1776 swap. I will fit twin 36 DRLA carbs, new exhaust, 123 vacuum distributor, new B&Ps. I will have to have a case and heads machined. I know I will have to strip the donor engine down and examine and measure the parts to check they are still reusable but generally speaking should I stick with all stock internals? Given that I am doing a basic 1776, the cost of a new Autolinea aluminium case seems a lot. I was surprised how cheap machining existing cases is. A neighbour in the village here said that there is a now a company doing new magnesium cases again? If buying a second hand case I am not sure how to check an engine case to make sure it can be machined and rebuilt or if it is too used? Other things I hear people talk about are 3 angle valve jobs, polishing the crank, porting and polishing the heads, external oil coolers, dynamically balancing the engine+clutch. Are these things I should be considering and anything else I should be considering, I am trying to learn but it is hard from just reading old threads. I have bought the book "How to rebuild your Volkswagen engine" by Tom Wilson.
Have a good read of Tom Wilson is what I suggest & take your time, it helped me no end when we built a type 4 motor. Talk to Snotty, Scrooge and others who have 1776' motors..
How is the case damaged? Give it a good looking over before use. Check end float before before you take the flywheel off. Will likely need a line bore and thrust cut. A good case is the most important bit. 3-angle valve job is worth having.
Heads - something to do right now before anything else is to cc them, get on an engine calculator and see where you are with CR with say 1.5mm deck. Will it work with a stock cam? After that yep to the valve/seat cut which any engine shop can do - they do it daily, it's not a VW special thing. Same for new guides if it needs them, which it probably does. Yours is the case with the hole that got bigger when some thoughtless welder imagined he could weld it IIRC? Old cases are risky - first thing to ask yourself is why, if it's useable, did the seller abandon it? You could gamble, but how many gambles before you find a good one? + the cost of then machining it and the time you'll spend going through all that.
Yes, there are new AS41 magnesium cases available again , I believe there were some issues with VW copyright and the company casting the cases being hauled through the courts as well as being hit by COVID. The thought I have is that maybe the Autolinea aluminium cases are more durable - I cant tell yet as my engine is only about 35k miles on from new, still has 16psi hot idle. As JK are EMPI retailers they do have the AS41 in stock, or can get them. And everything has become more expensive. I did see an Autolinea aluminium case on I think Custom and Commercial's stand with a price tag of £800 at the Vee Dub show the other week. JK though only seem to be listing bigger bore cases, and then all kinds of engines all the way down to Vege which I thought had sunk back into the swamps of quality. I paid about £2800 for a 1641 Preservation Parts engine in September 2018 - they are now £3474, which more or less reflects the sum of the cost of the new parts that go into the engine- the builders get a discount on parts that more or less pays for the labour involved . The £4314 for a 1776 is also a fair reflection of the cost of new parts. I did once buy an engine case for £51 on eBay, got about 25000 miles out of it but it needed JBWeld on its corroded base , and hours in a parts washer clearing corrosion from the oilways, caused by an inch of water in the sump, and the pistons were well rusted into the cylinders, needing the big hammer approach to free the cylinders in pieces from the pistons to get it apart. I think all that was recyclable was case, crank and flywheel as the camshaft gear had dissolved in the water ...
In your imagination. My imagination is JK or whoever supply the builder with the parts and a fee to build it. I guess it comes to the same thing. £800 for an ali case seems pretty good.
I was looking a bit harder at the prices as I might be able to afford a bigger engine myself in the near future. But then again for 90% of the time, a 1641 does OK and I have to back off occasion because the cooling doesnt keep up.. I got the feeling from paperwork style and phone numbers involved to contact for arranging exchange engine pickup that my JK preservation parts 1641 came direct from the VW Engine Company.
"How to rebuild your Volkswagen engine" will explain how to build a standard engine, but it doesn’t explain how to build a modified one. Read it to get the basics but do your own research, learn how an engine works and how changing one component may mean making changes to others. You intend to reuse the old heads, rocker gear, crankshaft and conrods, renew the crankcase, pistons and cylinders but what about the camshaft? The cam has a huge influence on how the engine performs and choosing the right one is critical. A 1776 with a standard cam will of course make more torque than a standard engine because it has more capacity and it’s probably a reasonable choice for a bus engine used for pottering around the countryside and climbing hills but not necessarily the best for cruising along motorways. Change the cam and the engine could make more power at higher revs but it wouldn’t be so good a low revs. You have to decide what you want the engine to do, understand the relationship between torque and BHP and how the characteristics of a cam changes the torque curve - and how much compression ratio is required. Choose the cam, then the pistons. 3 angle valve seats, crank journal polishing, head porting (don’t polish), an external oil cooler and dynamic balancing are all things you should be considering. But you don’t necessarily need any of them. For instance, depending on how you drive, a Type 4 oil cooler might be sufficient.
And maybe your engine ends up a blowing wheezing thing because it maybe got too hot.... I melted a piston with the oil at 95C with an external oil cooler and too much timing advance... Thats why I have the number on the dash now... Stopped, waiting outside the chippy because handing the boatyard £500 took such a short time.
To which the oil cooler is irrelevant. What's your point concerning this build? - don't dick with Heath-Robinson timing? You're the only person I know who does.
Top tips for engine longevity: 1. Learn how to set ignition timing correctly 2. Don't thrash the living nuts off your engine
Get a timing light that doesnt subtract about 4 degrees ..it was one of those with an analog dial to set the timing. Using an SVDA with points at the time, so it wasnt any peculiar distributor just set wrongly. The oil cooler was working perfectly at the time hence the 95C ... And @snotty we still dont know why your engine is somewhat sick...
As @77 Westy says, you might want to take a close look at the cam. They do wear (by a surprising degree) compared with a new one. A stock cam in a 1776 should be fine, or maybe one just a bit fruity-er. I've got an Engle 100 in mine, and it works fine, probably not too dissimilar to stock. Others are available. Nothing too hot, or all power/torque starts disappearing up the top end, which you don't want on a heavy bus.
So yes when I bought my van in June 2022 it came with a recent "recon" engine. The engine randomly sprung a leak at one of the lower rear oil galleries but luckily I discovered it soon after it happened as I was parking up so it didn't damage other internals. That case is unrepairable but all the parts are there available. I transferred all the ancillaries to a second hand long block which is an old Vege recon engine with poor compression that I bought from a air-cooled VW business in Dorset. I can't use my wrecked case. I don't want to use the case from the engine currently in the van as I am still able to use it to move the vehicle and it has already been rebuilt once, and it doesn't have proper T2 mounting points either. If a new case was available for £800 I would be prepared to pay that but from my searching, the only Magnesium case is by CSP in the states. The AU Autolinea cases for 1776 seem to be £1300-1500 and they are already sold out at Heritage and other places like JK selling out fast with no expected restock date listed. If I bought another second hand case to get machined it would be a complete gamble from someone on marketplace etc. It would be a hell of a lot cheaper than a new Autolinea case though. I have tried to do research which means going round in circles on threads from thelatebay, VZi, thesamba etc. It seems the conclusions I reached from all those threads was not popular on here (capacity and stroker engines). Also most of the threads address one specific issue whilst still catering to people with sufficient knowledge of vw air-cooled engine building. I will of course learn a lot by doing the basic work and reading the Tom Wilson book as I go. It feels a bit like the chicken and egg situation. I need to learn which seems to be from experience but I don't understand enough to start. My hope was that by building the engine myself I would learn (helpful when modifying or broken down) and also it would allow me to use a lot of my parts to keep the build as cheap as possible. Given that the 1776 engine is considered the proven reliable engine build I was hoping that there would be some general consensus on specifications on cams, valves, etc and recommendations and that someone could give me a specification list including cam etc so that I could progress and order parts. As I said I will be learning a lot just by carrying out the rebuild. At this stage to go into the science of learning about different cams and the technical details of it all while still learning about the overall build seems to be overwhelming and difficult. I can't find the explanations and advice needed at my level of understanding despite my research so far. I'm not sure what the most viable option is when it comes to an engine case now.
Thing is 99/100 of them are building engines for cars and those building bus engines are almost always building type-4 engines. AFAIK all US late bays were equipped with type-4 engines.
The problem is heat. The high performance engines store it in the engine metal on the drag strip for a quarter mile dash, so can produce hundreds of horsepower, but our 1600 cooling systems cant sustain the cooling at high horsepower levels for a say 50 mile motorway run. There is a certain amount of power needed to push an old T1 engined Beetle forwards at say 70mph and that would maybe push a bus forward at about 55mph, with the cooling system keeping up with the 25-30kW of waste heat. The 2L type 4 has massively uprated cooling to push a bus forwards at 70 mph.. So the 1776 comes in as it can go a bit faster, gets a bit hotter but in a bus will still be inside its cooling limits, because the air drag and weight of the bus holds it back from developing massive power. Your 1600 will be doing about 4200 rpm max. Same for the 1776. With all the racing mods, the same engine does maybe 7000 to 9000 rpm producing 2 to 3 times the power but only in a beetle, and only for minutes at a time. Yes you can fit a "freeway flyer" gearbox to but that makes the engine produce lower rpm for the same power/speed, slows the cooling fan and reduces cooling.. so you might end up with a cooler sounding engine but it doesnt go any faster or cool any better So you fit a cam that produces max power down at lower rpm compared with the Beetle. And the desire for magnesium cases is also partly driven by requring minimum mass for drag strip acceleration, the 25 lbs difference in weight in a bus is negligible. So you are left with either taking pot luck on a line of eBay AS41 cases or fighting to find a new case. Or taking out a loan for a decently built recon engine or new engine. I am sure new engine cases will reappear but there is a several year backlog of demand because of COVID and lawsuits.
