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Sat Nov 29, 2014 5:36 am

Hi Folks
I am RE-building the engine in my 74 Thing and would like to keep it close to stock. The question I have is about the crankshaft. Stock OEM vs Counter Weighted. What I am planning to do is me and the Wife will be taking a trip in the 74 Thing sometime next year. It will be about a 4000 mile round trip. The stock crank check good, Mains and rods all standard and it is straight. The question is while it is down and to make it reliable for the trip should I spring for a new counter weighted crank? If so I have seen the price all over the place from $139.00 to $600.00 and all different vendors. I keep reading to stay away from Empi products. Not sure about Scat or if I even need the counter weight crank. What I do not want is to breakdown on the trip and I would like this to be the last rebuild on the engine. Anyone have any experience on this or opinions?
Thanks

Sat Nov 29, 2014 6:25 am

If your just pleasure driving your thing i would just leave the stock crank in there as long as it checks out , now if your reving it and racing around then yeah i would up grade , but is it needed , NO ... hasnt your stock crank worked good for you all these years ??

Sat Nov 29, 2014 6:25 am

If you are keeping to a stock rpm range, the stock german crank is great quality, hard to beat. Get everything well balanced, you're set!

Sat Nov 29, 2014 7:09 am

Stock crank will do, however how long do you plan on keeping the engine? I went from stock to balanced and what a difference. When the whole rotating mass is balanced, so smooth, longer lasting.

Sat Nov 29, 2014 7:20 am

It is not the counterweighted crank that you feel, its the balance job.
- If you install a CW crank in a more or less stock engine, the only thing that really happens is that the engine becomes lazier due to the added reciprocating weight. (You will of course feel that) - If you lighten the flywheel 2 punds you will get it all back, and then some.

To the OP. If you are planning on a teardown/inspection, get the stock crank assembly balanced, also the rods and pistons.

Replace the cam with a CB 2280. Machine the case or the cylinders for correct deck height. Go 8,3-1 CR, good valve seat job etc. buy a 28 mm venturi from ACN, along with a good stock or mild performance exhaust. This will really wake up you stockish engine.

And no, for a stockish type of engine you do not need a CW crank. UNLESS you do a lot of crawling with the thing. Then the added crank weight may come in handy for slightly more torque reserves.

There is a German Guy, Merik, which I sold some parts to a couple of years back. He has built a 1776 std plus engine for his dad´s (I think it was) Thing. They had tried a few other solutions, but were not really satisfied with the engine until they built the last one here. I will see if I can get in touch with him so he can post the dyno sheet from it and tell for himself.
T

Sun Nov 30, 2014 7:39 am

Go with balanccd & not worry about pounding out case mains when u travel with todays traffic, if u dont u better keep 1 eye in rearview. As 4 the NO croud, how do u think the case mains got that way, gravity pull on the heavy crank?

Sun Nov 30, 2014 7:51 am

You do not need a counterweighted crank until you turn over 5000 RPM regularly. A stock crank is all you need for a mostly stock engine that will never see 5000 RPM.

Sun Nov 30, 2014 7:54 am

In the past few years i've rebuilt 5 stock 1600 and the owner wanted a CW crank. They all said the engine ran smoother and accelerated quicker. Maybe it was a placebo affect but if the stock crank is fine... use it. If it needs to be replaced, CB sells a nice 69CW crank for under $200.

Sun Nov 30, 2014 11:11 am

If you are going to use 85.5mm P&Cs, use the stock crank. Reason is that the skirts will hit the counterweights on a CW crank. Yes you can clearance the skirts and rebalance the pistons, but that's normally beyond a "stock build" for most folks.

If you are using larger P&Cs, absolutely go CW.

Sun Nov 30, 2014 8:00 pm

[email protected] wrote: If you are going to use 85.5mm P&Cs, use the stock crank. Reason is that the skirts will hit the counterweights on a CW crank. Yes you can clearance the skirts and rebalance the pistons, but that's normally beyond a "stock build" for most folks.

If you are using larger P&Cs, absolutely go CW.

Even on a CW 69mm crank?

Sun Nov 30, 2014 8:01 pm

You'll find the piston skirts on 85.5, 87, and 88mm pistons will often hit the counterweights on the crank. This is normally not a problem with 90.5-94mm

Mon Dec 01, 2014 8:20 am

[email protected] wrote: If you are going to use 85.5mm P&Cs, use the stock crank. Reason is that the skirts will hit the counterweights on a CW crank. Yes you can clearance the skirts and rebalance the pistons, but that's normally beyond a "stock build" for most folks.

If you are using larger P&Cs, absolutely go CW.

I have never seen that happen. What brand CW crank and P & B's? I have seen that all the time when using the 83mm on 1200cc engines.

Tue Dec 02, 2014 10:51 am

so why is it every non cw crank engine Ive tore appart has been line bored some many times, or that need line boring.but Ive never had a cw cranked engine that needed it........we all know the vw crank is the best crank in the world :shock: and the work vw did was also the best in the world :shock:vw balanced the cranks..why would they not be right?? :wink: so........oh ya I have never built a vw using the stock crank or stock rods.I see no reason to do so the parts were inferrior to just about anything that can be bought cheeper than a regrind&recon. :shock:
use what your head tells you to use and your wallet can afford.

Tue Dec 02, 2014 11:23 am

I should have said "...can hit the crank counterweights", rather than "will".

So much 'depends'.

Cranks have small and big CW. Which? Cast Mahle's hit, forged ones have shorter skirts and clear. Just check it. Know what you are getting in to.

Tue Dec 02, 2014 11:26 am

Because the factory tolerances were way wider than what we balance at today. It is not uncommon to remove 5-6 grams on a stock crank, plus some at the flywheel, and then again some, add some on the pressure plate.
Add, to that, rods and pistons 5-7 grams out and it becomes a problem.

Most China forged cranks for ACVW aint that bad, but minor adjustments are almost always performed.

T

Tue Dec 02, 2014 12:16 pm

most "rebuilt engines" are slapped together, nothing is balanced. Assembled, not "rebuilt".

Tue Dec 02, 2014 12:29 pm

I just pulled my 1776 apart after 7 years of four season daily driving. I don't really know what that is in miles. Plenty. There's a Berg cruise and several cross-country trips in there. I don't baby it on the freeway, 70-75 mph tank after tank all day when I'm traveling.

The crank is a Berg 69 CW. I paid a local circle track engine shop to balance the entire rotating assembly (type-3) and the reciprocating parts as well.

The case and main bearings all look great. The thrust bearing still fits perfectly in the case. These bearings will get a light polish and go right back in the engine.

Max

Tue Dec 02, 2014 1:30 pm

the 1641 I built for an old guy had a cast cw crank(brazillz impovi crank) it had good piston clearance but the counter weights hit the main webbing thus the case needed clearancing. always check everything....3 times.and another 4 times after you fix it. :wink:

Mon Dec 08, 2014 3:05 am

I have decided to stick with the stock crank. Building a stock engine and the stock crank measures absolutely perfect. It will last as long as I do if I take proper care of the vehicle.

Thanks for the advise
G

Tue Dec 09, 2014 4:36 am

you could have your cake and eat it too,,,,,,get a stock cw crank from Jose at DPR ,absolute best of both worlds !!!!