Coolbore honing

Well I've got at least 4 aluminum blocks to get ready and spring is just around the corner. I have beautiful wonderful gorgeous chrome Briggs pistons and my local kart racer/supplier/ machinist, who is a real good guy, is not into aluminum engines. He is more than ready to bore these to whatever size I want but can not, will not, does not know or need to know, the intricacies of the cool bore.
Here I am asking the experts; what do I do once the bore is close and I need to hone to size? I'm thinking the regular stones are going to be WAY to course, so I need help!
 
You definitely don't want to use regular stones .
Its a special stone for aluminum .
I've read just about everything on here in reference to honing, some guys use 600? grit stones, some even use scotch-brite? The more I see on different forums its almost like the original bores were coated or treated to make them harder? Or might be urban legend I dunno.

Sure would like to do the right thing the first time...
 
You can use standard stones with the AN600 honing head, but you'll want to use progressively finer grits and plateau finish at the end. We will polish the cylinder with crocus cloth wrapped around the stones for our final bore finish in an aluminum bore.
Aluminum bores (from the factory) are NOT coated or plated. You "can" have them Nicasil coated if you choose, but that is not legal for WKA, IKF, etc. stock class racing.
A Wiseco or full skirt piston (chromed or coated) will be fine in an aluminum bore. The Raptor 3 pistons (coated or not) will not live long in an aluminum bore because of their barrel shape and sharp short skirt design that rocks too much and wipes out the thrust side of the cylinder.



-----
🏁Thanks and God bless,
Brian Carlson
Carlson Racing Engines
Vector Cutz
www.CarlsonMotorsports.com
Carlson Motorsports on Facebook
33 years of service to the karting industry ~ 1Cor 9:24
Linden, IN
765-339-4407
bcarlson@CarlsonMotorsports.com
 
You can use standard stones with the AN600 honing head, but you'll want to use progressively finer grits and plateau finish at the end. We will polish the cylinder with crocus cloth wrapped around the stones for our final bore finish in an aluminum bore.
Aluminum bores (from the factory) are NOT coated or plated. You "can" have them Nicasil coated if you choose, but that is not legal for WKA, IKF, etc. stock class racing.
A Wiseco or full skirt piston (chromed or coated) will be fine in an aluminum bore. The Raptor 3 pistons (coated or not) will not live long in an aluminum bore because of their barrel shape and sharp short skirt design that rocks too much and wipes out the thrust side of the cylinder.



-----
🏁Thanks and God bless,
Brian Carlson
Carlson Racing Engines
Vector Cutz
www.CarlsonMotorsports.com
Carlson Motorsports on Facebook
33 years of service to the karting industry ~ 1Cor 9:24
Linden, IN
765-339-4407
bcarlson@CarlsonMotorsports.com
That’s how we used to do them, finished off with crocus wrapped around the hone.
 
We had some stuff made by Sunnen for aluminum bores, looked kinda like runny lapping compound. Then we riveted some leather pads onto some wore out stones. After a good lapping of the bore it was a dark Grey color and was a little work hardened. It supposedly had some effect on the silicon in the aluminum.
 
No big secret, I use 220 grit stones on my Ammco hone, light pressure and use allot of fluid (kero) to keep the stones from loading up.
 
The stuff Jon Brogden was referring to was a Silicone based paste Sunnen developed for the final hone on a Chevy Vega aluminum bore engine. Worked great on the flathead.

We used a tennis ball with a hole drilled thru it and a washer with a nut welded to it and two sheet metal screws run through the washer into the tennis ball on each end.

Used a long piece of 3/8"all thread in a drill and tightened nuts to compress ball for desired tension.

This was final step after honing on the AN-600 with two grades of stone, and then the crocus wrap.
 
You can use standard stones with the AN600 honing head, but you'll want to use progressively finer grits and plateau finish at the end. We will polish the cylinder with crocus cloth wrapped around the stones for our final bore finish in an aluminum bore.
Aluminum bores (from the factory) are NOT coated or plated. You "can" have them Nicasil coated if you choose, but that is not legal for WKA, IKF, etc. stock class racing.
A Wiseco or full skirt piston (chromed or coated) will be fine in an aluminum bore. The Raptor 3 pistons (coated or not) will not live long in an aluminum bore because of their barrel shape and sharp short skirt design that rocks too much and wipes out the thrust side of the cylinder.



-----
🏁Thanks and God bless,
Brian Carlson
Carlson Racing Engines
Vector Cutz
www.CarlsonMotorsports.com
Carlson Motorsports on Facebook
33 years of service to the karting industry ~ 1Cor 9:24
Linden, IN
765-339-4407
bcarlson@CarlsonMotorsport
The piston info troubles me. I havta use these pistons and it was hard enough getting them. I will endeavor to make the clearance as small as possible.
 
The piston info troubles me. I havta use these pistons and it was hard enough getting them. I will endeavor to make the clearance as small as possible.
What pistons do you have that you are forced to use?
Are you racing sanctioned events, or what application are these engines going on?
If allowed, you can have pistons coated. I still wouldn't suggest using R3 pistons (coated or not) in an aluminum bore.
 
What pistons do you have that you are forced to use?
Are you racing sanctioned events, or what application are these engines going on?
If allowed, you can have pistons coated. I still wouldn't suggest using R3 pistons (coated or not) in an aluminum bore.
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I was under the impression these are R3 pistons, it's really hard to get flathead parts here, hopefully the border relaxes and I can order some better stuff.
 
I was under the impression these are R3 pistons, it's really hard to get flathead parts here, hopefully the border relaxes and I can order some better stuff.
That is a Briggs R3 chrome piston.

We have R3 pistons in stock. (Both Burris and Briggs.)
Chrome Briggs R3 pistons are getting rare.

Have you considered sleeving or Nikasil coating the block(s) to use these pistons. They are great pistons and rings, just don't work well with aluminum bores. Sleeving is legal for sanctioned racing, Coatings are not. We can sleeve blocks with a hardened steel sleeve to whatever bore size you tell us (including standard bore.) BUT, we are already super busy here in the shop and have several blocks here to be sleeved currently.

FedEx is still shipping across the border just fine.
Give us a call if we can be of any help.

-----
🏁Thanks and God bless,
Brian Carlson
Carlson Racing Engines
Vector Cutz
www.CarlsonMotorsports.com
Carlson Motorsports on Facebook
33 years of service to the karting industry ~ 1Cor 9:24
Linden, IN
765-339-4407
bcarlson@CarlsonMotorsports.com
 
That is a Briggs R3 chrome piston.

We have R3 pistons in stock. (Both Burris and Briggs.)
Chrome Briggs R3 pistons are getting rare.

Have you considered sleeving or Nikasil coating the block(s) to use these pistons. They are great pistons and rings, just don't work well with aluminum bores. Sleeving is legal for sanctioned racing, Coatings are not. We can sleeve blocks with a hardened steel sleeve to whatever bore size you tell us (including standard bore.) BUT, we are already super busy here in the shop and have several blocks here to be sleeved currently.

FedEx is still shipping across the border just fine.
Give us a call if we can be of any help.

-----
🏁Thanks and God bless,
Brian Carlson
Carlson Racing Engines
Vector Cutz
www.CarlsonMotorsports.com
Carlson Motorsports on Facebook
33 years of service to the karting industry ~ 1Cor 9:24
Linden, IN
765-339-4407
bcarlson@CarlsonMotorsports.com
Brian how can you tell a piston is chrome or not? By the numbers or just by experience?
 
You can tell by the part number or by simply looking at it.
"Chromed" doesn't imply shiny when it comes to pistons...it is more of a dull gray coating.
Raw machined aluminum is much more shiny than a chromed piston.
 
When we raced cool bore, Sunnen had a special stone and a wiper type you replaced stone with to finish and a compound that you used to work into the porous cylinder walls to help longevity. General Motors developed it for the Vega's aluminum block and cylinder wall with cast iron pistons. Really bad idea. Never helped them but worked good on our cool bores. Got to use a torque plate no mater what you do. I probably got some chrome lined pistons around. Better off putting in a iron sleeve it or just find a I/C block. you'll have a lot more options and a motor that will last a long time. Irons rings and aluminum cylinder wall doesn't play well together. Remember the grit on the stone is going to imbed into the cylinder wall, you got to figure out how to work it out or your going to hone your piston while its running. Part of why the sunnen procedure the wiper would heat up wall to release imbeded grit compound would take it away while filling void with slick goop while stayed in a while and worked out to help lubricate things.
 
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