Reliability: The most common concern regarding porting that I hear is a decrease in reliability. While that can be true, what it really means is an increase in the frequency of the maintenance interval. Put simply, as your engine gets pushed harder, the components will wear faster, and therefore need to be replaced sooner. So it is not necessarily a decrease in reliability that occurs, unless you as the operator of the engine do not keep up with the wear items and therefor allow failure to occur. The most common increase in wear on a ported cylinder is the collapse of the piston skirt. As the exhaust port gets wider, the rings have a harder time passing by it with every stroke. This causes the piston to rock back and forth to a higher degree, causing an increased wear on the rings, exhaust port, and piston skirt. For example, if a cast piston in a stock Kawasaki 750 is set at 0.004" clearance, it may take 100+ hours for it to reach the wear limit of .008" where it will need to be replaced and possibly bored again depending on the out of round of the cylinder bore. On a Stage 3 Cylinder with a much wider exhaust port, this same piston will reach that wear limit much faster. What this means for you, is that on a ported cylinder, expect to have to hone and install a fresh set of pistons sooner than you would on a completely stock cylinder. Not a big deal by any means, but something simply overlooked much of the time leading to failure and the stigma around ported cylinders. And as you would expect, as the stage of porting gets higher, so does the frequency of the maintenance interval. Another important aspect is the shape of the exhaust port. The more squared off at the top, the more aggressive this wear will be. We tend to keep the top of the exhaust port more rounded to allow the rings more time to make their way back into the bore relative to a squared off port.
We offer 3 stages of cylinder porting, 1 being the most basic and 3 being the highest performance. Each model of engine and type of use (recreation, freestyle, racing) will have different needs, but the description below gives you a basic overview of what to expect from us at each given stage. We can tailor each of these various stages to your specific type of use and the particular engine. Pricing listed is per cylinder and does not include parts, bore/hone/chamfer, Piston & Ring Balance & chamfer.
Stage 1: We describe this stage as blueprint porting. Removing all casting flaws, evening out the height and width of all transfer and boost ports according to desired use, adjusting roof angles based upon desired use, conservative exhaust port modification. This is our most common stage that we do here. It will offer the best bang for the buck and keep reliability as close to stock as possible. $200 per cylinder.
Stage: 2: All of Stage 1 plus a more aggressive exhaust port, mild modification to the sleeve skirt. $250 per cylinder.
Stage 3: All of Stage 1 and 2 plus heavy sleeve skirt modification, heavy boost port modification, and piston boost porting/ modification. $300 per cylinder.
STAGE 1 CYLINDER PORTING
PRICE IS PER CYLINDER. EXAMPLE: KAWASAKI JS750 WILL NEED QTY OF 2.
Stage 1: We describe this stage as blueprint porting. Removing all casting flaws, evening out the height and width of all transfer and boost ports according to desired use, adjusting roof angles based upon desired use, conservative exhaust port modification. This is our most common stage that we do here. It will offer the best bang for the buck and keep reliability as close to stock as possible. $200 per cylinder.
Stage: 2: All of Stage 1 plus a more aggressive exhaust port, mild modification to the sleeve skirt. $250 per cylinder.
Stage 3: All of Stage 1 and 2 plus heavy sleeve skirt modification, heavy boost port modification, and piston boost porting/ modification. $300 per cylinder.
STAGE 2 CYLINDER PORTING
PRICE IS PER CYLINDER. EXAMPLE: KAWASAKI JS750 WILL NEED QTY OF 2.
Stage 1: We describe this stage as blueprint porting. Removing all casting flaws, evening out the height and width of all transfer and boost ports according to desired use, adjusting roof angles based upon desired use, conservative exhaust port modification. This is our most common stage that we do here. It will offer the best bang for the buck and keep reliability as close to stock as possible. $200 per cylinder.
Stage: 2: All of Stage 1 plus a more aggressive exhaust port, mild modification to the sleeve skirt. $250 per cylinder.
Stage 3: All of Stage 1 and 2 plus heavy sleeve skirt modification, heavy boost port modification, and piston boost porting/ modification. $300 per cylinder.
STAGE 3 CYLINDER PORTING
PRICE IS PER CYLINDER. EXAMPLE: KAWASAKI JS750 WILL NEED QTY OF 2.
Stage 1: We describe this stage as blueprint porting. Removing all casting flaws, evening out the height and width of all transfer and boost ports according to desired use, adjusting roof angles based upon desired use, conservative exhaust port modification. This is our most common stage that we do here. It will offer the best bang for the buck and keep reliability as close to stock as possible. $200 per cylinder.
Stage: 2: All of Stage 1 plus a more aggressive exhaust port, mild modification to the sleeve skirt. $250 per cylinder.
Stage 3: All of Stage 1 and 2 plus heavy sleeve skirt modification, heavy boost port modification, and piston boost porting/ modification. $300 per cylinder.
Cylinder Boring/ Finish Hone/ Chamfer
Our Cylinder machining process is specifically tailored to the needs of the 2 and 4 stroke race machines. Our process is designed to insure that you get the most out of your high dollar investments (Porting/ Decking/ Big Bore Sleeving/ Head Machining/ Etc).
-Many slow passes to help reduce tool deflection into ports
-3-stage finish honing process with the proper degree/grit to allow hard coated rings to properly seat
-IJSBA Race Legal Port Chamfer (A critical step missed by most not familiar with 2-strokes)
Price is per cylinder up to 1mm. Overbore charge of $20 per cylinder over 1mm.
Piston/Ring Balance/Chamfer/Ring Gap Service
Time to go the Extra mile for our customers. These few extra steps will not only increase piston and Cylinder life, but allow you to get more efficiency/ power out of your race engine.
Basic set up including:
-Set Ring End Gap according to our specs
-Balance Pistons by weight
-Chamfer Pistons
-Chamfer Ring Ends
$30 per Piston
|
Our new location in Bastrop Tx!
C57RACING.COM 1270 STATE HIGHWAY 71 W STE 100 BASTROP TX, 78602 512-265-1419 [email protected] |