Title: offset grinding crank Post by: Jesse Wens on May 03, 2013, 19:08:56 pm I would like to have a crank offset grind.
Offcourse I have heard about Demello en DPR but does anyone have an addres in Europe? Would be for a regrind to chevy journal making for a bigger stroke and preferably nitrading afterwards. So I don't think any welding is necesary but I could be wrong, not realy sure about the oilpassages. Thanks Jesse Title: Re: offset grinding crank Post by: wph on May 03, 2013, 22:01:51 pm Expect to pay at least 80-100 euros per crankpin + nitriding depending on where you start at (53 or 55mm),
it is a quite time consuming process. Any competent machine shop with a crankshaft grinder can do it, nitriding services may be more difficult to find Title: Re: offset grinding crank Post by: Taylor on May 03, 2013, 22:35:07 pm I want to say the last one I had done here in the states at Castillo's Crankshaft Specialties was around $400 and change total. Just to send it out for nitride was like $150. As far as your oil holes, it is best to start with a crank that has them drilled on center. Especially if your going a long way, 5mm+, or the hole will be elongated by the time the crank is ground. It's also a good time to have a large radius put on the journal shoulders.
Title: Re: offset grinding crank Post by: RMS Boxer Service on May 04, 2013, 09:37:08 am DPR have just that kind of product on the shelf and at $185. At that price it's even 8 doweled and balanced.
For another $45 you can have it heat treated. Hard to beat that price !! José make some awesome cranks and I have allwas been happy with the DPR cranks I have used. /Rolf Title: Re: offset grinding crank Post by: MeXX on May 04, 2013, 12:08:02 pm Dear Jesse
First of all I understand why you want to do this, I did it myself for my OKRASA WBX crank going from 82 to 82,6 and from crankpin 55 to 55 - 0,75. It's really allot of work :'( :'( . You just have to ask yourself is it worth the work and the money. If it's not really a very rare crank and really worth I would highly recommend buying a new one. So keep on strokin' MeXX Title: Re: offset grinding crank Post by: Jesse Wens on May 07, 2013, 19:52:09 pm hey,
The crank is a good condition long stroke WBX crank. The idea behind this is to be able to use chevy rods and gain a bit of stroke. As I don't see a lot of good places apear in europe I´m guessing it might be better and maybe cheaper in the long run to try Demello or DPR. Jesse Title: Re: offset grinding crank Post by: Jesse Wens on May 08, 2013, 10:29:21 am I got a qoute from a local company that would do it for 350-400.
Nitrading would be 200-250. Sounds about right? Title: Re: offset grinding crank Post by: richie on May 08, 2013, 10:53:50 am Jesse
how quicly do you want it done? I ship stuff to and from the states regularly and could send it over to DPR to get done way cheaper? cheers Richie Title: Re: offset grinding crank Post by: Jesse Wens on May 08, 2013, 11:26:16 am Hey Richie,
There´s no hury. It´s for next years engine. would be nice to have it begin 2014. Please let me know what you can do for me (and what I could do in return ;) ) Thanks Title: Re: offset grinding crank Post by: richie on May 09, 2013, 09:38:58 am PMed you
cheers Richie Title: Re: offset grinding crank Post by: jaqo on May 09, 2013, 19:19:54 pm If you want to, I can do it for you here in Poland - we have some VERY competent specialists and low prices. For example nitriding is something like 50$ per crank. I guess grinding would be around 70-150$ Shipping is not that expensive too.
Title: Re: offset grinding crank Post by: dangerous on May 09, 2013, 20:18:01 pm You have to be careful with the 76mm WBX crank because
the oil holes will move closer to the side of the journal when you stroke it. I have seen cracks start from this position, and it is only then, a short distance to the critical radii. If you look at the 69mm one, the oil holes are machined with the same settings, so the journal/oil hole relationship is better placed. But either way as you stroke them the oil hole outlet ends up in a worse position. Late type 1 and type 4 cranks all use this oil hole system, which is why the older 6 volt cranks are best for stroking. They have a single oil hole, to the rod journal, that is better placed. A 'switched on' crank grinder could index the journal a little so that when stroking, the area near the oil hole is barely touched. BUT, you would have to re-index your timing marks. Title: Re: offset grinding crank Post by: Jesse Wens on June 04, 2013, 06:53:02 am A 'swithced on' crank grinder could index the journal a little so that when stroking, the area near the oil hole is barely touched. BUT, you would have to re-index your timing marks. I understand what you are saying here. I've never heard of it done though. Do you have some experience with it? Guess you just have to put in some extra work indexing your cam. Got a quote from DPR today. Check for cracks Grind the mainbearings first undersize (0.25) Weld and grind center main to type 4 Grind the rodbearings to 2 inch chevysize offset style ( 80 mm stoke ) Weld counterweights Nitrade afterwards 575 dollar or 440 euro Sounds reasonable for a crank jose claims will take about 400 horsepower no problem. |