need advice on 1835 motor

[JeeWee]

Hi callookers,

Yesterday an old friend of mine offered me his 1835cc motor, and the price is very interesting, but I am in doubt if I could use this engine for my bus, so would like your advise.

Some specs about the engine:

69mm OG VW crank with welded on counterweights by Ahnendorp B.A.S. (germany)
lightened pushrods fully balanced (top and bottom)
complete crank with flywheel, pushrods, clutch and pully dynamically balanced
hot camshaft, I don't know the specs.
mahle 1835 92mm Piston and cylinders
Magnum 044 heads with 40mm X 35,5mm valves, reworked and flowed, matching manifolds
original Weber 44IDF
no exhaust
fan shrouds etc.
Most of the parts and labour come from Ahnendorp, no cheap stuff used.
The price is nice in my opinion, as it costed him something like 5000euro's to buildt all this, especially all the extra work which was done to do it 'perfectly'.


But, now my issue is that I would like to use the motor in my 1972 T2 singlecab, and I do not need a hot and nervous engine, but would like a nice torque engine to cruise the pickup everywhere I want on long trips to events and holidays. A bit like the engines which are currently offered by ahnendorp http://www.ahnendorp.com/VW-Kaefer-Typ-1-Motorenteile-und-Bearbeitungen/Complete-packages-VW-Beetle-type-1-engine/1835ccm-Typ-1-Zentralvergaser-Konzept-Ahnendorp-B-A-S-.html

To make this engine work for my bus my current plan is to swap the hot cam for a mild cam, and also swap the Weber 44's and use a 39mm solex single carb (which is a big bore 34 pict) to keep the stock look. The only thing which raises a question mark are the 044 magnum heads. Would that work in that setup, those big valve heads on a single carb engine.  what are the pro's en con's of big valves? And what are the pro's and cons of the 044 magnum heads? I heard they have better cooling?

thanks in advance for your advice

[Martin S.]

I wonder about this too. Calling 40x35.5 'big valve heads' is kinda of like calling a warmed over 1776 a 'performance engine' though. The heads are so close to stock that I don't think there will be any difference. For example, I have a high compression 1776 in my wife's 65 bug and it has a wonderful low end that the original 40hp engine would never have. My 041 heads have the 40 intake valves but still have the stock size 32 exhaust valves. I wish it had the bigger exhaust valves like your heads to get rid of the heat better but the fact remains that it doesn't matter that much. The extra compression and bump up in displacement is a good thing, along with a precision build. Mine has a stock cam which would be fine in yours too.

[Zach Gomulka]

My advise, install the engine how it is.

If it begins to run warm, find a way to cool it better.

If you do not like the powerband of the engine, take it apart and make the appropriate changes (cam, etc).

I would not consider removing the Webers for a stock carburetor. Stock carburetors are for stock engines.

[Martin S.]

Don't look at the cam as being a problem in its 'hotness'. Cams being too 'hot' are only a problem when they are used in the wrong engine. For example if you put a stock carb or heads on that engine, the cam would be too hot. But if you have the webers, the cam is perfect. My 2332 street bug has a HUGE cam in it and is not nervous at all because the engine has all the corresponding characteristics that make that cam perfect for that engine. I bet that 1835 your friend has is a good engine for your bus as is. Run it.

[Dougy Dee]

Isn't it presumptive to give advice without knowing your tolerance for 'fiddling', what camshaft and what compression ratio the engine was built around?

[JeeWee]

I'll try to get some more info on the cam and heads and CR tonight. With hot motor I meant indeed more that he told me that the engine is nervous, so cruising around at low RPM's isn't very easy.

[Martin S.]

It probably has a cam with a lot of overlap like a Engle 110. You get a lumpy idle with those and a stock engine is smoother if you're crawling along.

[Torben Alstrup]

Imho you would most likely be better off starting from scratch if you want a stock look engine. big valves and hot cams are not needed for that kind of engine. 1835 thin wall cylinders are also not the best for a bus. I´d say walk away, unless it is REALLY cheap.

T

[Martin S.]

For a 'stock' style motor using stock intake and exhaust I would recommend more displacement and compression as it worked well for me. My next motor like this didn't happen with the idea for my bus engine was to do this the hard way. We were going to use the 85.5 stock bore long stroke P/C's from Aircooled.net and build a stroker engine with stock bore. The reason was to gain torque and have excellent fuel economy at the same time. This is what BMW and others do. The air cooled VW motor was designed with a large bore to cool well through the aluminum heads and to counteract this problem we were going with the high squish flame port chamber with tight deck. A lot of work but would be very cool to build this.

[Zach Gomulka]

Imho you would most likely be better off starting from scratch if you want a stock look engine. big valves and hot cams are not needed for that kind of engine. 1835 thin wall cylinders are also not the best for a bus. I´d say walk away, unless it is REALLY cheap.

T

I agree with this... Worse case scenario it can be rebuilt into a 1776 or a thick wall 1835 with a more conservative cam if/when it needs to be.

[Martin S.]

Why not the 'big' valves? Are 40x35.5 considered big valves by most people? Note the motor he was looking at did not have a stock muffler.

[Torben Alstrup]

Nothing wrong with larger valves as such. But for an engine like that he is searching to get there is absolutely no need. Stock valved heads would give better overall performance for the induction type and power window he is after.
One of the key factors for centercarburated engines is to have a port volume not exceeding "X" % of the displacement. With large valves and ports that is easily exceeded. Going above this point and the will definitely run, but you will soon discover that you are only moving the power around (typically loosing lower end and gaining a little upper end) One exception to that is if you are really choking the engine with a small carb on a larger displacement. Then you can run into the behaviure that the engine will actually pull  better below say 3000 rpm but still pull about the same at peak, because the time area along with carb flow simply do not alow for more mix to come through the system.

T