The Cal-look Lounge

Cal-look/High Performance => Pure racing => Topic started by: Diederick/DVK on February 21, 2009, 15:38:16 pm



Title: counterweights or balanced stock
Post by: Diederick/DVK on February 21, 2009, 15:38:16 pm
for a relatively low budget project i'm weighing the alternatives of purchasing a new CB Performance 69mm c/w crank or a new stock 69mm crank, which is (obviously)cheaper as i've got my eye on one. the remainder of the money would then be spend on balancing the pulley, crank, flywheel and pressure plate, which we will not be doing in the case of the new crank, cos it is rather low budget.

the engine we're dealing with is a hot 1600 single port engine in a line-bored mexico case.

i'm not sure about which of the 2 (counterweights or a balanced bottom end) would work out best, the only pro of buying a c/w crank would be to retain it when upgrading to a larger bore at a later stage.

please let us know your thoughts.  :)


Title: Re: counterweights or balanced stock
Post by: louisb on February 21, 2009, 16:06:52 pm
If you are not going to rev it above 5500 then you won't need counter weights. I would spend the money on a good balance job.

--louis


Title: Re: counterweights or balanced stock
Post by: Diederick/DVK on February 21, 2009, 17:39:57 pm
cam will be 242º @ 0.50 with 0.420" lift and for now the heads are stock 1600 s/p. so it won't be that much of a high revving engine.


Title: Re: counterweights or balanced stock
Post by: Harry/FDK on February 21, 2009, 17:51:31 pm
CW.


Title: Re: counterweights or balanced stock
Post by: j-f on February 21, 2009, 18:11:39 pm
I think you will use a vz14. I'm building the same engine and I use a stock balanced cranck with a taiwan damper pulley. I follow the advices of the guy I buy parts.

He says that taiwan pulley on a balanced crank with a stock weight flywheel is a good combo for a mild street engine and will give a good reliablity.


Title: Re: counterweights or balanced stock
Post by: Doktor on February 21, 2009, 22:09:34 pm
I think you will use a vz14. I'm building the same engine and I use a stock balanced cranck with a taiwan damper pulley. I follow the advices of the guy I buy parts.

He says that taiwan pulley on a balanced crank with a stock weight flywheel is a good combo for a mild street engine and will give a good reliablity.

I've heard something similar few days ago on the Samba from a guy under nick SRP1 - he wrote that he builds engines for off-road racing based on a ballanced stock crang (non C/w) without lighthening a flywheel and in combination with equalizer pulley...and no negative effect on the bottom end or the case. Engines are revved more than 5500 rpm frequently !
He was mentioning that Gene Berg did the same thing years ago...


My plan is to build 1776ccm with Webcam 163 (between Engle 110 and 120) with ballanced stock internals and Equalizer pulley or even with Engle 120 - I'm not sure 100% !


Title: Re: counterweights or balanced stock
Post by: Sander/DVK on February 22, 2009, 01:42:58 am
Go for the 82 DPR  ;)


Title: Re: counterweights or balanced stock
Post by: Dougy Dee on February 22, 2009, 05:29:56 am
Aren't the new stock cranks cast? ???


Title: Re: counterweights or balanced stock
Post by: Jim Ratto on February 22, 2009, 06:41:28 am
Aren't the new stock cranks cast? ???

yep


Title: Re: counterweights or balanced stock
Post by: j-f on February 22, 2009, 11:34:17 am
Aren't the new stock cranks cast? ???

Yes, I don't mention that but he says me to use an old one. Stock new are just enough for a stock use...



Title: Re: counterweights or balanced stock
Post by: tikimadness on February 22, 2009, 11:42:51 am
I would go for an old stock non counterweight crank

Michael


Title: Re: counterweights or balanced stock
Post by: Jesse/DVK on February 23, 2009, 10:57:05 am
I have a stock old one lying around with stock 180mm flywheel. Donnow how good it is but for a small fee it's yours :P


Title: Re: counterweights or balanced stock
Post by: Diederick/DVK on February 23, 2009, 14:12:11 pm
i've got two myself, but a grind and polish will set me back 260 euro's. a CB crank is 250 and a full balance job is 180.

hence, this topic. i'm trying to weigh the alternatives...


Title: Re: counterweights or balanced stock
Post by: Jesse/DVK on February 23, 2009, 15:02:06 pm
I would go for a DPR than.. 85 bucks for a stock one.


Title: Re: counterweights or balanced stock
Post by: Lee.C on February 23, 2009, 17:09:09 pm
"counterweights or a balanced bottom end"

BOTH!


Title: Re: counterweights or balanced stock
Post by: Sander/DVK on February 23, 2009, 17:35:22 pm
i've got two myself, but a grind and polish will set me back 260 euro's. a CB crank is 250 and a full balance job is 180.
An rebuild stock crank cost you 140 euro's by Ahnendorp, when you change it with your old crank.

But why not a stroker engine? You have beautiful heads and good set of carbs. Go for it!


Title: Re: counterweights or balanced stock
Post by: Diederick/DVK on February 23, 2009, 17:44:32 pm
this is not for myself sander, i've got all my parts sorted  :)
besides i should be able to haul some ass with my stock stroker  :D ;)

this is for my brother, what started out as a sweep the floor engine plan is now changing with new parts. but he's spending a lot of money on a sprayover so i don't want to take it too far in terms of $$. gotta disappoint you there, lee. though you're right of course.

it's only a 1600 in the end. i'll take a look at ahnendorp then.


Title: Re: counterweights or balanced stock
Post by: Jim Ratto on February 23, 2009, 17:56:16 pm
1. first choice: Rimco 69mm c/w orig VW crank
2. second choice: stock 1600 x drilled orig VW crank (don't use a 6V crank if you're using a 12V o-ring type flywheel)

don't use a new stock replacement crank
(aftermarket)

have you looked on Samba for a used CW like yours?


Title: Re: counterweights or balanced stock
Post by: Diederick/DVK on February 23, 2009, 18:00:42 pm
i've got the crank from my 1300 s/p engine and from a 1600 d/p engine. but both could probably need a regrind.

he'll be using my old 180mm flywheel for now, as it's been lightenend and i've got a low mileage clutch and p/p to go with it.

don't use a new stock replacement crank

have you looked on Samba for a used CW like yours?

copy that.
and will have a go there too.


Title: Re: counterweights or balanced stock
Post by: bugkeeper on February 24, 2009, 23:48:02 pm
A good old german forged original 69mm crank wil do just fine. Far better than any cheap chinese cast "counterweight" crank.
I used one in a 1915cc engine and it would rev up to 6500 rpm with no problem. Just get it balanced and use an equalizer pulley.
The main advantage of a good counterweight crank is it saves your main bearing saddles in the case. I guess it depends on how many miles you plan to put on that engine. German forged better than any cast crank. Else go with a DPR crank. Good crank for the money. Also check out AJ. Sims at low bugget.


Title: Re: counterweights or balanced stock
Post by: Diederick/DVK on February 24, 2009, 23:49:41 pm
the problem is that i'm guessing my crank needs a grind and that very pricey over here...