Late bay 74 camper. Type 1 1600 twin port. Just done a compression test and it has very low compression (65/99/95 65) so needs at the least a top end rebuild. I've just bought the vehicle so don't know how good the rest of the engine is. I'm new to air cooled and so have been researching the myriad of options that seem to be available. I'm perfectly capable of rebuilding the engine so don't want to buy a complete unit but would appreciate some advice. A number of the parts companies sell kits of parts to rebuild and upgrade my engine to 1641, 1776 etc. up to 2 litre and more. Are these kits worth it? Should I be looking for certain makes over others? It seems sensible at this point to also consider a carb upgrade to twin carb? Which combination of size/ performance upgrade would give me a reliable 75k mile engine that's happy sitting at 65/70 on a motorway and wont destroy the rest of the bus in the process? Budget excl. carbs is probably about £1k Is that enough? Thanks for your input. Richard
For anything bigger than 1641, you'll need to machine the crankcase and heads, so they're not bolt-on upgrades.
Bigger means more acceleration/less/no slowing on hills, but cruising speed is always going to be limited by the cooling. 70mph will be pushing the the cooling to the limits. 1776 is easiest worthwhile upgrade - same crank but larger B&P's so case and heads need machining. Bigger needs a longer throw crank with all that entails. Kits above 1641 are a US thing I think and will be a whole engine rather than a rebuild kit I think. Budget depends on what you do.
As a pointer, when I was looking at building my own 1776, the machining work alone was about £300 (including full flow and polishing the crank).. Balancing everything up was about another £100.
As said above I would go 1641cc B&P's, a mild cam and new lifters, https://www.vwheritage.com/shop/AC198870R/barrel-piston-kit-1641cc-87mmx69mm-repro/ https://www.vwheritage.com/shop/AC109110/engle-w110-cam-kit/ and then refurb what you have, (remember forum members get a discount with us) far cheaper than a grand, Get a set of carbs and an exhaust and your away, anything more requires machining to the case and heads and the costs start escalating very quickly. If you do go down that route (apart from carbs) its as cheap to go 2276cc as 1776cc, your going to pay for machining I'd say go big go once. You will need to factor in an external oil system into the cost if going above 1641cc too. Hope this helps.
I build a 1641 with a mild performance cam, goes very well. I'd recommend it and it's all bolt on bits with no machining.
try and find someone with a 1641 to take you for a spin, then you can see if you are happy with the power
hypothetically...how would a (stock) 1.7/1.8/2.0 T4 motor compare to mildly updated T1...say with 1641cc + E110 cam + a pair of ITCs...? There are threads about which admonish one to upgrade brakes, etc, inline with engine performance, but did VW practice this approach? Where any such changes made to Busses with T4 motor over those with a T1 (or is the performance 'improvement' small enough not to need any changes!)? P.
As all of VW stock busses go about the same top speed and weigh about the same give or take a quarter ton of Westfalia or Devon woodwork and plastic, the late bay brakes are quite adequate. The US only got servos because you are meant to be able to able to stop with a ton of load in the back with a cup of coffee between your knees and a donut in one hand..
110 cam is too much for the cc's IMO A 1641 is a mopeds worth more welly than you have as standard. A lot of people do see a remarkable performance improvement, but IMO this is largely because their old engine was knackered (hence rebuilding it)! There is no substitute for increasing the CC's. The advantage T4 engines have is that they are generally sturdier and have better cooling. A similar spec T1 or T4 engine should perform similarly, my 2020cc T1 managed 134HP peak on the rolling road. Top Bananas similar spec T4 (cam, valve sizes, carbs) did about the same. T1 performance parts are much, much cheaper than T4 parts so it's cheaper to have some fun, though perhaps easier to break and they have a slightly lower safe cruising speed due to the cooling (or lack of).
Exactly this^^ A 1641 is a 14cc per cylinder increase... Not worth it in a bus IMHO, I'd always stick with the thicker 1600 barrels on a bus motor!!
Of course if you already have a 2L T4, you're already a good size to start with - change cam, bigger valve heads, slightly bigger B&P's and you're away. To get there with a T1 requires a different crank, then you might worry about the case and decide a new aluminium one would be a good bet. It's swings and roundabouts - most people seem to stick with the basic engine type that came with the bus - A T4 because it's "better" or a T1 because it's "cheaper".
Tbh...the question really was hypothetical As it happens the 1600 motor in my bus is functioning reasonably well for the most part, but I do have a 1700T4 motor and a set of 1641 Bs & Ps. As and when the existing motor needs pulling for some reason, I'll probably upgrade ine way or another...but no rush.
That's ok, I can spot a hypothetical question. The comparisson is interesting. £25 for a pair of bolt on rocker covers for T1, £100 for T4 - that's a typical T1/4 comparisson. Pair of big valve T1 heads for just over £400 - try getting ONE T4 big valve head for that - I think not.
Zed - when you mention the cooling maxing out is that because of the high revs/more heat generated rather than an issue with the cooling system So raising the gearing would solve that - i.e. fitting a 2.0 litre gearbox or crown wheel and pinion. Cant afford that option at the moment but if I go for more CCs now I can upgrade the final drive later. Just mustn't thrash it in the meantime...
To give you an idea, my 1641 engle 110 twin weber ict's gave a whopping 57 BHP on the rolling road. The engle 110 like to be kept above 2500 rpm, really around 3000 to keep its power. once there though it pulls well. I always regretted not going 1776. so that is what is going to happen in the autumn. Might as well go 1600 and get the heads worked a little.
Its trying to drive a brick through the airflow below 70 it manages above that it has to work a lot harder expedentialy Ill be running a 1776 without an external cooler and have no doubt that if i sit at 65 on the motorway with a 3 rib gear box i wont have any cooling problems With a type one you can run an external oil cooler to bring the oil temp down but theres nowt you can do to bring the cylinder head temp down
