knecum
Novice Class
Posts: 54
|
posted October 14, 2010 05:11 PM
 Edited By: entropy on 15 Oct 2010 04:51
Thanks Jim your alot smarter then me, im just a confident engine builder, and racer.. I really think i can put a busa engine together blind folded if the parts and tools are layed out. Thats including putting the cams in, but just stock ones.. I was actually thinking of making a video of me doing it for shits and giggles.. I've just built that many of them.. I like the mirror finish on the cylinders myself...= less friction= hp.. Bob does them like that..
____________
engines on a bench
  
|
ZRXDean
Needs a job
Posts: 2225
|
posted October 15, 2010 08:45 AM
quote:
Hey Steve welcome.
There are several factors in a proper hone.
1 the cross hatch angle.
2 the grit of the stone.
3 the stone material.
The stone material is key to cylindricity. Honing a bore for 20 minutes and not removing very much material is just a waste of time and productivity but it also makes the cylinder all wavy and tapered and not round. Bad for ring seal. Fresh stones with good equipment helps create good cylindricity but compared to the new technologies GM is using today for the LS-7 block bores our Sunnen CV 616 is primitive.
The grit is dependant of the rings used as is the cross hatch angle. The ring manufacturer will tell you what they recommend. The rings wont last long or wont ever sea if the RA finish is too smooth or too coarse. Its a balance between oil retention and seal. Some rings don't need much oil retention and some need a rough initial finish to seat.
Theres also plateau finishes which is what these modern bike cylinders need to have wityh these low tension hard rings. That's where you use two different stones, diamond in this case, to finish the bore off. You knock off the tops of the mountains with a very fine stone very quickly at the end.
One thing to note is that most bores are never really cleaned properly before assembly. it takes quite a while with several cleaners to get ALL the crap out of the cross hatch.
Hey Steve! Good luck to the team in Texas next week, wish I could be there to see it.
Jim, are you talking about nikasil bores here?
Dean
|
wrongway
Pro
Posts: 1078
|
posted October 15, 2010 04:16 PM
here is a good article ... It is a bit dated , but has some good info
http://www.enginebuildermag.com/Article/2300/the_smooth_science_of_cylinder_honing.aspx
|
Y2KZX12R
Needs a job
CompetitionCNC.com
Posts: 3762
|
posted October 16, 2010 05:13 AM
Edited By: Y2KZX12R on 16 Oct 2010 13:38
Steve, I'm just the 5 axis CNC cylinder head part of the shop, my partner Bill Carlquist is the brains behind the whole rest of the engine machining, assembly, and dyno testing side of the shop.
Any real technical process questions I would defer to him for answers.
quote:
Jim, are you talking about nikasil bores here?
Dean
Yes, diamond stones are used on the hard chrome bores or hi nickel silicone and some other hard liners.
/``\/``\/``\ plateau vs regular /\/\/\/\/\/\/\ a crude example but you get the idea.
{quote] Here is a good article ... It is a bit dated , but has some good info
http://www.enginebuildermag.com/Article/2300/the_smooth_science_of_cylinder_honing.aspx
Yea that is a good read..... that explains a lot of what I was talking about.
____________
Y2KZX12R
CompetitionCNC.com
|
|
|
|
|
HOME
NEW TOPIC