Cylinder taper/out of round

[Anonymous]

My experience with honing

I have had blocks distort as much as .0018 at the top of the cyls when a torque plate is installed. if you checked it with no plate id say your probaly within a couple tenths with a plate. A couple tenths is nothin to worry about and your machine shop probaly checked this with a plate installed. If block was runned before id just run a glaze breaker through it.

 

[CNC BLOCKS]

Put a torque plate on the block and then measure the cylinders if you think .0015 is bad wait untill you check it qowith a plate then you should see around .003 to .004 distortion in the clylinders.

If the shop your dealing with don't do plate honing it may be time to find a better shop that does performance work.

If its just a stock engine it maybe fine but if its a performace engine and it has more clylinder pressure then a stock engine you will see signs of blowby and its hard to get rings to seal in cylinders with distortion. And 400 blocks are the worst ones.

Good luck with your build Carl

 

[Anonymous]

http://www.northernautoparts.com/ProductModelDetail.cfm?ProductModelId=14216

if you read through it says what hastings has to say about cyl. taper. the last engine i put together (230der. at 50 lift cam,9.5comp.,dbl humps...) was a used block and had .013 to .015 taper between cylinders and ran just fine with no real noticable blowby.

just my 10cents

Joe

 

[Anonymous]

WOW!!! I guess I'm a little late, didnt realize how old the last post was.

 

[big-angry-hillbilly]

No big deal Joe - your numbers are way higher than mine, so I think my motor will live just fine

I'm about .003 taper.

Thanks

 

[Redline396]

in my opinion it also depends on what piston you use...you can hone that engine back to round,for example....how much clearance do you need between the piston and cylinder wall?some pistons require more clearance than others due to expansion rates when hot....or for power adders...ie..turbo,blower,nitrous,ect......with that small amount of tapper i would not worry about it...and for rings i only use speed pro barrel faced,they seal real well on cold engine starts when the piston is rocking in the bore more.....again only my opinion.....btw i am running a big block 463 with .005 clearance between the skirt and cylinder...recommended for street strip using icon pistons....good luck on the build.........ken