Searching for info on Sunnen CV-616 stroker mod.

[crosshatch]

I made my own and it works great . I went to SAM and used the nascar bar and I loved it . That was my first modification to my cv616 when I got it . Here's a pic of mine :
http://community.webshots.com/photo/533 ... 0714AIJKOr
I will try to take more pictures of the whole working on it today if I get a chance .
GJ

Thank you much GJ.......
That's exactly what I was looking for.
According to rumors I have heard, an engine builder for one of the top Nascar teams had invented this trick item sometime in the 70's or 80's.

[BCjohnny]

Right......

Having jumped into this prematurely before, and having quite rightly been shot down , I thought the only decent thing to do was revive a dying thread.................

Mike. The "unofficial" view is that although most people won't use it (much, if at all), sales may suffer if it's not fitted/option. At least over here.

And I took the lid off mine to look and it's a VERY easy mod. Forget all that crap I wrote before (which would work but would be way too much trouble), all you need to do is create the linkeage shown so it takes the pressure off the spring loaded idler pulley, allowing the "v" belt that drives the recipro box pulley to slip. Probably less than a mornings work.

So I'll have a go and hopefully post some decent pics. But it'll be a month or two, after I've finished re-building my Jones & Shipman Univ.Grinder, and make a centerless grinding attachment for it, to do valves. At nigh on two tons weight I don't expect much chatter..........

John.

[jimivice]

This is a late post because like BC Johnny I was not familier with the "Nascar bar". I have read "Wolfplace's" explanation and the "Nascar bar" seems to be a justifiable modication to the CV 616. BC Johnny posed the question, why hasn't Sunnen incorporated this modification in their machines? If it was so important? Wolfplace claims, the modication has been used for years. BC states albeit time consuming with constant gauging he can hold tolerances to an acceptable limit without the use of the "Nascar bar". Wolfplace finds the "Nascar bar" a usefull modication to keep the cyls. straight. I agree with both frames of thought. It must be remember when the CK10 was developed (the precurser to the CV616) the use of torque plates were in their infancy - I think this is the impedence of the contriversy. The advent of big bores, wider bore centers, and head bolt relocation might require the "Nascar bar" modification. There becomes a point where the bore size is equivalent to the bore size in the torque plate. Dowels pins are not used to allow the positioning of the torque plate, so as not have the stone interfere with the torque plate - when honing.Torque plate bores can only be so big before they crack when torquing -especially aluminum torque plates. The accepted method of dropping the block to work the top of the cyl. becomes ineffective because either the stones will hit the torque plate, the inserts, or head bolt washers - if you trying to duplicate the actual running conditions. It is a lofty goal, but unacheivable. I have done aircraft honing and the idea is not to create a condition that you can't correct. This means constant gauging and/or modications, ie; "Nascar bar" to keep the hole round and straight.

[jimivice]

This is in reference to my last post. It might be oversimplifyed but it is a common mantra between me and the person I have great respect, "You are as only as good as your mandrel". Even after constant gauging and the modifications that might be deemed necessary.If the tooling is not kept up - it is a moot point.

[Big Speed]

We bought the dwell kit for our CK10 back in the 80s, cant recall who sold it ,one of the engine builder supply companies,worth its weight in gold .

[gem]

We also have this mod on our CK10. It's been there for at least 20 years.

I tell new operators that it's there to get you out of trouble!

I cleaned the tag and could still read it

S.S. Products
Toronto, Ontario, Canada
416-754-2275

I have no idea if they are still in business.

[Robert Kane]

I posted this for just the same question in another thread. A fellow on eBay goes by the seller name "kentclub" sells a kit for just such a dwell stop for the CK-10 and CV- 616. He is in Ontario, Canada. Great guy, honest too. I believe he worked for Sunnen too.
I hope that helps you.
Robert

[ProPower engines]

I know this is an old thread but the fellow mentioned on ebay that goes by Kent club is the guy that invented the conversion.While he is still currently selling them at a cost of $249 USD he is retiring soon and if anyone wants this conversion they should think about getting it soon as they will be gone till some one copies it

[modok]

I'll let you in on a secret.
There is a ratchet on the crown that feeds out the stones, a lever on the back, I made a bushings that goes on there and pulls the pawls away, so the crown is not locked. This lets you adjust the honing pressure at will as it strokes. You can hone JUST the top or the bottom, or anywhere in the cylinder if you TIME your wrist to the stroke. And if your reflexes are not great, just run it slower. It can work great. Stone pressure is increased and decreased gradually.
Should you you DWELL in the ring travel? I'm thinking no.

[zums]

I'll let you in on a secret.
There is a ratchet on the crown that feeds out the stones, a lever on the back, I made a bushings that goes on there and pulls the pawls away, so the crown is not locked. This lets you adjust the honing pressure at will as it strokes. You can hone JUST the top or the bottom, or anywhere in the cylinder if you TIME your wrist to the stroke. And if your reflexes are not great, just run it slower. It can work great. Stone pressure is increased and decreased gradually.
Should you you DWELL in the ring travel? I'm thinking no.

You must be double jointed, i just went through this with my bowtie block 5 months ago, bottom of 3 cylinders were hard, created a .003 taper, had to get the dwell handle where you can stop the honing head at any position and still adjust pressure, tried everything before that, overstroke, electric dwell, cut the stones, this was the only thing that worked, pain in the ass
Tom

[modok]

I'm not double jointed.
But, that's the bottom of the cylinder, it's a totally different kind of problem.