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Make them larger displacement. Often big bore kits are new pistons and juggs also. A common one for your sled in a 660 kit.
 

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Pretty much it ends up making your engine put out more HP and Torque.
 

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xcsp_rider said:
could i do this to my 500 edge how much cost?
The 660 kit I priced was 2500. So spendy if your me
 

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Or to clean up the bore if you have a burndown.

A .030 over bore on a 600CC sled equals to like 3.25cc or something.. Not worth it.

EDIT- This can be figured out with basic bore and stroke variables and the circle formula (something with Pie), which I need some refreshing on.

A "big bore" is for HP, like the Carls kit for a smallblock 5-600 to a 660.
 

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^^^ That's honing and is a completly different deal.
 

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^^ No hes right, you don't hone .030 off a cylinder wall its usually bored out with a boring bar. Honing is usually done to "deglaze" the cylinder and leave a crosshatching.
 

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Negative Dekk70.
boring is as mentioned aboe by Luke68 and normally does not give much, if any more power.
It is used for taking broken ring scratches etc out of cylinder walls etc.

To gain power and displacement, one normally has to replace the jugs, slugs, and rings. Quite often the heads too. Then then to do it right, there is normally case porting and matching everything up to make it all flow properly.
This is doing a big bore kit.
 

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I honestly have no idea what the cylinder walls are made out of on your 500, but I know most Ski-Doos 2000+ use nicacil coated cylindes. A new nicacil coating is about $200 per cylinder. Then boring prices vary. Steel cylinders are cheaper to bore as you dont have to get them coated again. Another downside to boring out a stock cylinder is that there is less material for the heat to disperse to, meaning your motor could run hotter and not as efficient. Although not usually the case, it can happen.
 

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skidooguymxz550 said:
hmmmmmm, guuuuys, what does stroking mean?[:p]
Haha. But seriously now. Displacement of a motor is not just about bore. It also has to do with how long of a stroke the motor has. A 600cc 2 cylinder engine can have a larger bore than a 700cc 2 cylinder, but a shorter stroke. So a longer stroke means more displacement.

For instance, a 383 stroker is actually just a 350sbc with a 400 crank. Of course there USUALLY is more modification when building a stroker, but its pretty simple.
 

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My stock 700 twin polaris motors have a 81mm piston with a 68mm stroke, equaling of course 700cc's, I have a big bore setup that has had the stock 700 cylinders bored out and then had steel sleeves installed to accept 85mm pistons, with the 4mm overbore my total displacement comes out to 770cc's, the sleeves in the cylinders can be safely taken out to increase my total displacement to a maximum of 780cc's, nicasil plated cylinders can be stripped and over bored and re plated, the polaris 700 cylinders can be done out to a 735 or 754 big bore and still have the cylinder re plated, anything bigger than that they will need to be sleeved.
 

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Another 'weird' Physics thing about boring and engine, is, as surpising as it seems, you'll find that it raises compression.Ask around. increase in cylinder volume, vs squeeze space.....
 

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Luke68Polaris said:
Or to clean up the bore if you have a burndown.

A .030 over bore on a 600CC sled equals to like 3.25cc or something.. Not worth it.

EDIT- This can be figured out with basic bore and stroke variables and the circle formula (something with Pie), which I need some refreshing on.

A "big bore" is for HP, like the Carls kit for a smallblock 5-600 to a 660.
pi(3.14)*R(radius)(squared)*L(length)=total area for a cylinder
output=area*AP(applied pressure)dependant on compression and combustion.
That's without any loss of energy through the valves, piston rings and exhaust. That's why
well timed engines and well designed exhaust pipes increase power.
 

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sledcrusher said:
For instance, a 383 stroker is actually just a 350sbc with a 400 crank. Of course there USUALLY is more modification when building a stroker, but its pretty simple.
Acually, a 350 with a 400 crank leave you with 377ci. And when you use a 400 block with a 350 crank it comes out to a 377ci engine aswell.

The most common 383 built is the 350 block bored .030 over with the 400 crank, this gives you a truck 383ci.

Theres also a few other things that have to be done aswell due to the 400having an externally balanced crank... Not as simple as just taking a 400 crank and putting it in a 350.
 

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crdude said:
sledcrusher said:
For instance, a 383 stroker is actually just a 350sbc with a 400 crank. Of course there USUALLY is more modification when building a stroker, but its pretty simple.
Acually, a 350 with a 400 crank leave you with 377ci. And when you use a 400 block with a 350 crank it comes out to a 377ci engine aswell.

The most common 383 built is the 350 block bored .030 over with the 400 crank, this gives you a truck 383ci.

Theres also a few other things that have to be done aswell due to the 400having an externally balanced crank... Not as simple as just taking a 400 crank and putting it in a 350.
The reason he said that is because most people that build a stroker bore it .030 as well. I dont think i've seen anyone leave it as a 377. The blocks also have to be clearanced for the 3.75" of stroke.

I've always been curious as to how much compression boring an engine actually adds. Obviously this depends on how big the bore and stroke already are. But, in general, does boring actually have a significant impact on compression ratio?
 

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Dekk70 said:
^^^ That's honing and is a completly different deal.
Nice try son!
 

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First off sledcrusher that was just a lame explanation of everything that was wrong. Yes it is a 350 with a 400 crank(if done right usually a forged crank). But clearance is an issue and machineing is required. Done with 30 overbore and typiclly 6inch rods. Also tends to go to a 1.6 roller rocker ratio to help the friction aspect after running a higher crompression ratio and for reliability. Also usually done with a high volume oil pump and a completely balanced assembly(blueprinting). I take it your dad must have one of these engines right?
 

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indyrmk30 said:
crdude said:
sledcrusher said:
For instance, a 383 stroker is actually just a 350sbc with a 400 crank. Of course there USUALLY is more modification when building a stroker, but its pretty simple.
Acually, a 350 with a 400 crank leave you with 377ci. And when you use a 400 block with a 350 crank it comes out to a 377ci engine aswell.

The most common 383 built is the 350 block bored .030 over with the 400 crank, this gives you a truck 383ci.

Theres also a few other things that have to be done aswell due to the 400having an externally balanced crank... Not as simple as just taking a 400 crank and putting it in a 350.
The reason he said that is because most people that build a stroker bore it .030 as well. I dont think i've seen anyone leave it as a 377. The blocks also have to be clearanced for the 3.75" of stroke.

I've always been curious as to how much compression boring an engine actually adds. Obviously this depends on how big the bore and stroke already are. But, in general, does boring actually have a significant impact on compression ratio?
Depends on what you would deem significant. As an example, Will it go from 9:1 to 10:1?? Probably not. Most likely .1 or .2 increase. This is if you use the same style of replacement piston. Maybe I should rephrase that a bit. If you use a replacement piston that has the same "compression ht" (measured from pin center line to top of the piston crown), there will only be a slight increase. My example is for a .020" (.5mm) overbore.
 
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