- Home »
- FAQ
CP Carrillo FAQ
- FAQ
- Privacy Policy
- Shipping & Returns
- Frequently Asked Questions - Pistons
- My ring pack has 3 rings, but my piston only has 2 ring grooves. Did I get the wrong ring pack? Or was the piston made incorrectly?
- Why do I have an extra set of Spiral locks?
- Where can I get more stickers?
- What is the difference between lateral and vertical gas ports?
- What is the difference between CP-CARRILLO and BULLET Series Pistons?
- What is Cam and Barrel shape?
- What is an X-style forging/piston?
- What are non-rotating wire locks (KRAMM LOX)?
- What are billet pistons?
- Ring orientation
- Ring end gaps?
- Ring Dimension terminology
- Piston to wall reference chart for different bore types.
- I want to supply CP-Carrillo with a model to make my new pistons, what’s the best way to do this?
- I broke a ring during the install, can I just use OEM rings with this piston?
- How much ring end gap should I run? (Answered on pages 2 & 3)
- How much lift will your piston take?
- How long does it take to make Custom Pistons?
- How do I request a catalog?
- How do I know my piston to wall clearance, and where do I get the measurement? (Answered in question: “Piston to wall reference chart for different bore types.”)
- How do I identify Tops, 2nds and oil rings?
- How do I identify my CP-CARRILLO or BULLET Pistons?
- How do I cut ring grooves?
- How do I become a dealer?
- Do you have a minimum quantity of pistons I need to buy?
- Can you coat my pistons?
- Can I purchase rings for your pistons?
- Can I order direct?
- Are all your pistons forged?
- Frequently Asked Questions - Rods
- Why do we Rockwell each connecting rod?
- Why do we Magnaflux each connecting rod at least twice?
- Why are CP-Carrillo rods made from a forging?
- Why are CP-Carrillo connecting rods Shotpeened?
- What is the process that makes CP-Carrillo different from the mainstream parts?
- What is the difference between WMC and CARR Fasteners?
- What is Carrilloy
- What is a Spec Card?
- What is a CP-Carrillo Connecting rod
- Useful tips for Fastener Installation: Torque vs Stretch
- Truth about Horsepower
- Support
- Quality Assurance
- How do I know if I have a CP-Carrillo rod?
- Do you sell a Bolt Stretch Gauge?
- Do you offer a Reconditioning Service?
- Do I need to use CP-Carrillo Lube when installing my connecting rod?
- Can I buy a spare connecting rod?
- Are CP-Carrillo rods heat treated?
- Frequently Asked Questions - Hardware
- MAP Policy
- Terms and Conditions
- Rings
- What is the difference between CP-CARRILLO and BULLET Series Pistons?
- What do we recommend for Ring Honing?
- Ring orientation
- Ring end gaps
- Ring Dimension terminology
- My ring pack has 3 rings, but my piston only has 2 ring grooves. Did I get the wrong ring pack? Or was the piston made incorrectly?
- I broke a ring during the install, can I just use OEM rings with this piston?
- How do I identify Tops, 2nds and oil rings?
- How do I cut ring grooves?
- My ring pack has 3 rings, but my piston only has 2 ring grooves. Did I get the wrong ring pack? Or was the piston made incorrectly?
- Why do I have an extra set of Spiral locks?
- Where can I get more stickers?
- What is the difference between lateral and vertical gas ports?
- What is the difference between CP-CARRILLO and BULLET Series Pistons?
- What is Cam and Barrel shape?
- What is an X-style forging/piston?
- What are non-rotating wire locks (KRAMM LOX)?
- What are billet pistons?
- Ring orientation
- Ring end gaps?
- Ring Dimension terminology
- Piston to wall reference chart for different bore types.
- I want to supply CP-Carrillo with a model to make my new pistons, what’s the best way to do this?
- I broke a ring during the install, can I just use OEM rings with this piston?
- How much ring end gap should I run? (Answered on pages 2 & 3)
- How much lift will your piston take?
- How long does it take to make Custom Pistons?
- How do I request a catalog?
- How do I know my piston to wall clearance, and where do I get the measurement? (Answered in question: “Piston to wall reference chart for different bore types.”)
- How do I identify Tops, 2nds and oil rings?
- How do I identify my CP-CARRILLO or BULLET Pistons?
- How do I cut ring grooves?
- How do I become a dealer?
- Do you have a minimum quantity of pistons I need to buy?
- Can you coat my pistons?
- Can I purchase rings for your pistons?
- Can I order direct?
- Are all your pistons forged?
- Why do we Rockwell each connecting rod?
- Why do we Magnaflux each connecting rod at least twice?
- Why are CP-Carrillo rods made from a forging?
- Why are CP-Carrillo connecting rods Shotpeened?
- What is the process that makes CP-Carrillo different from the mainstream parts?
- What is the difference between WMC and CARR Fasteners?
- What is Carrilloy
- What is a Spec Card?
- What is a CP-Carrillo Connecting rod
- Useful tips for Fastener Installation: Torque vs Stretch
- Truth about Horsepower
- Support
- Quality Assurance
- How do I know if I have a CP-Carrillo rod?
- Do you sell a Bolt Stretch Gauge?
- Do you offer a Reconditioning Service?
- Do I need to use CP-Carrillo Lube when installing my connecting rod?
- Can I buy a spare connecting rod?
- Are CP-Carrillo rods heat treated?
- What is the difference between CP-CARRILLO and BULLET Series Pistons?
- What do we recommend for Ring Honing?
- Ring orientation
- Ring end gaps
- Ring Dimension terminology
- My ring pack has 3 rings, but my piston only has 2 ring grooves. Did I get the wrong ring pack? Or was the piston made incorrectly?
- I broke a ring during the install, can I just use OEM rings with this piston?
- How do I identify Tops, 2nds and oil rings?
- How do I cut ring grooves?
Privacy Policy
Q: Website Disclaimer
Q: Use of your Personal Information
CP-Carrillo does not sell, rent or lease its customer lists to third parties. CP-Carrillo may, from time to time, contact you on behalf of external business partners about a particular offering that may be of interest to you. In those cases, your unique personally identifiable information (e-mail, name, address, telephone number) is not transferred to the third party. In addition, CP-Carrillo may share data with trusted partners to help us perform statistical analysis, send you email or postal mail, provide customer support, or arrange for deliveries. All such third parties are prohibited from using your personal information except to provide these services to CP-Carrillo, and they are required to maintain the confidentiality of your information.
CP-Carrillo does not use or disclose sensitive personal information, such as race, religion, or political affiliations, without your explicit consent.
CP-Carrillo keeps track of the Web sites and pages our customers visit within CP-Carrillo, in order to determine what CP-Carrillo services are the most popular. This data is used to deliver customized content and advertising within CP-Carrillo to customers whose behavior indicates that they are interested in a particular subject area.
CP-Carrillo Web sites will disclose your personal information, without notice, only if required to do so by law or in the good faith belief that such action is necessary to: (a) conform to the edicts of the law or comply with legal process served on CP-Carrillo or the site; (b) protect and defend the rights or property of CP-Carrillo; and, (c) act under exigent circumstances to protect the personal safety of users of CP-Carrillo, or the public.
Q: Use of Cookies
One of the primary purposes of cookies is to provide a convenience feature to save you time. The purpose of a cookie is to tell the Web server that you have returned to a specific page. For example, if you personalize CP-Carrillo pages, or register with CP-Carrillo site or services, a cookie helps CP-Carrillo to recall your specific information on subsequent visits. This simplifies the process of recording your personal information, such as billing addresses, shipping addresses, and so on. When you return to the same CP-Carrillo Web site, the information you previously provided can be retrieved, so you can easily use the CP-Carrillo features that you customized.
You have the ability to accept or decline cookies. Most Web browsers automatically accept cookies, but you can usually modify your browser setting to decline cookies if you prefer. If you choose to decline cookies, you may not be able to fully experience the interactive features of the CP-Carrillo services or Web sites you visit.
Q: Security of your Personal Information
Q: Image Disclaimer
Q: Contact Information
Q: Changes to this Statement
Q: Collection of your Personal Information
There is also information about your computer hardware and software that is automatically collected by CP-Carrillo. This information can include: your IP address, browser type, domain names, access times and referring Web site addresses. This information is used by CP-Carrillo for the operation of the service, to maintain quality of the service, and to provide general statistics regarding use of the CP-Carrillo Web site.
Please keep in mind that if you directly disclose personally identifiable information or personally sensitive data through CP-Carrillo public message boards, this information may be collected and used by others. Note: CP-Carrillo does not read any of your private online communications.
CP-Carrillo encourages you to review the privacy statements of Web sites you choose to link to from CP-Carrillo so that you can understand how those Web sites collect, use and share your information. CP-Carrillo is not responsible for the privacy statements or other content on Web sites outside of the CP-Carrillo and CP-Carrillo family of Web sites.
Shipping & Returns
Q: What shipping options are available?
Online orders will be shipped based on the customers choice at checkout. We (do not) ship to P.O. boxes. Please contact us if you are interested in an expedited shipping on your order.
Q: What could cause a shipping delay?
Shipping delay can occur when the wrong address or zip code is submitted for the shipping address. If the shipping company can not deliver the package we will contact you via phone or email.
During the holiday season shipping delivery may vary.
Q: Is there a cost on returns?
If an item needs to be returned the shipping fees are the customer's responsibility.
Amount of refund will be based on the purchase price of your product.
Frequently Asked Questions - Pistons
Q: My ring pack has 3 rings, but my piston only has 2 ring grooves. Did I get the wrong ring pack? Or was the piston made incorrectly?
Neither. What you have is a 2-ring piston designed to utilize the top and oil rings ONLY. Simply throw away your second ring and install as normal. NOTE: If you see a V-shaped groove below the top ring groove, that’s actually an Accumulator Groove and you can’t put a ring in it.
Q: Why do I have an extra set of Spiral locks?
CP-CARRILLO and BULLET include double Spiral locks with most off-the-shelf pistons. Most shelf pistons that are designed to use Spiral locks utilize 2 per side (4 per piston). For instance, an 8 cylinder motor would come with 32 Spiral Locks whereas a 4 cylinder would only come with 16. Wire locks only require one per side (2 per piston).
Q: Where can I get more stickers?
Contact your WD or send your name and address to sales@cp-carrillo.com and we will put a decal package in the mail for you.
Q: What is the difference between lateral and vertical gas ports?
Lateral gas ports are channels drilled at the bottom of the top ring land that assist in ring seal. These channels allow combustion gasses to enter behind the top ring and improve ring seal by forcing the ring against the cylinder wall during combustion. Gas ports are most commonly used with back cut rings, which have less friction and better performance characteristics.
Q: What is the difference between CP-CARRILLO and BULLET Series Pistons?
Both CP-CARRILLO and BULLET are high quality forged pistons, made from 2618-T61 Alloy. CP-Carrillo pistons are designed for high performance racing engines and are available for many "race specific" applications. Additionally, CP-Carrillo can be custom made in as little as 3 days to your specification. BULLET Series Pistons are large production runs on centralized manufacturing cells made from dedicated “Bullet” forgings. An application specific forging, as well as manufacturing in larger quantities reduces machining time. We pass the savings on to you, offering a more economically priced part, made on the same machines as a traditional CP!
In addition, the BULLET Series features a quality 1.2mm, 1.5mm, 3.0mm ring package and includes Chromoloy wrist pins with wirelocks. The 1.2mm carbon steel nitrided top ring is extremely durable and offers reduced friction over 1.5mm and 1/16" top rings. A 1.5mm Napier (hooked face) 2nd ring is used to improve oil control over conventional taper-faced rings.
Q: What is Cam and Barrel shape?
Based upon a few different variables, cam / barrel shape is the curvature built into the piston to insure the correct amount and rate of expansion. As the motor approaches operating temperature, the cam insures that the aluminum piston and the aluminum/ steel/ cast iron cylinder all achieve optimum operating temperature / shape at the same time.
Q: What is an X-style forging/piston?
X-Style forgings are designed to minimize friction and reduce weight without compromising strength. With the use of bracing and ribs, the forging is configured by adjusting the weight balance between high and low stress areas. This design enables the use of a shorter pin for added strength and weight savings.
See figure 5
Q: What are non-rotating wire locks (KRAMM LOX)?
They are designed to directly replace standard wire locks with no additional machining to the pistons and will not rotate in the lock groove. Click here for more information
Q: What are billet pistons?
Billet parts originate as solid blocks of aluminum and are normally used in the rare instances when forgings cannot produce the optimum design.
Q: Ring end gaps?
Due to the wide variance of expansion rates typical of power adders (nitrous, turbos, etc.), air cooled versus water cooled, marine applications, etc., it can be difficult or impossible to give ring end gap recommendations that will be accurate across the board. Please be aware that the information provided is only a guideline and that any concerns should be addressed with your engine builder. All information is provided in inches of ring gap per inch of bore. EXAMPLE: A recommended ring gap of .0040 per inch on a motor with a 4.000 inch bore would yield a ring end gap of .016 inches as .0040 x 4.000 = .016
DOMESTIC AUTOMOTIVE: Normally Aspirated (no power adders) up to 600hp.
- Top Ring = .0045 - .0050 per inch of bore
- Second Ring = .0050 -.0055
- Oil Rings – Actual gap = .015-.050
DOMESTIC AUTOMOTIVE: Normally Aspirated over 600hp and turbo/nitrous applications below 750hp.
- Top Ring = .0050 - .0055
- Second Ring = .0055 - .0060
- Oil Rings – Actual Gap = .015 -.050
DOMESTIC AUTOMOTIVE: Turbo/Nitrous applications above 750hp.
- Top Ring = .0060 - .0070
- Second Ring = .0070 - .0080
- Oil Ring – Actual Gap = .015 - .050
SPORT COMPACT: Normally Aspirated to 300hp
- Top Ring = .0040 - .0050
- Second Ring = .0045 - .0055
- Oil Ring – Actual Gap = .015 -.050
SPORT COMPACT: Turbo/Nitrous applications to 450 - 750hp
- Top Ring = .0050 - .0055
- Second Ring = .0055 - .0060
- Oil Ring – Actual Gap = .015 - .050
POWERSPORTS: Normally Aspirated
- Top Ring = .0040 -.0045
- Second Ring = .0045 - .0050
- Oil Ring – Actual Gap = .015 - .050
POWERSPORTS: Turbo/Nitrous applications
- Top Ring = .0045 - .0050
- Second Ring = .0050-.0055
- Oil Ring – Actual Gap = .015 -.050
Q: Piston to wall reference chart for different bore types.
Your pistons should have come with a Spec Sheet that will have the recommended piston to cylinder wall clearance written on it, as well as where the piston should be measured. As always, you’ll want to consult with your engine builder to verify whether that is the correct clearance for your application. NOTE: You cannot accurately measure your piston to wall clearance by sliding a flat feeler gauge into a round hole next to an elliptical object (piston).
EXAMPLE: Bore = 3.898 / Piston measurement at gauge point = 3.895 / Remaining piston to cylinder wall clearance = .0030Q: I want to supply CP-Carrillo with a model to make my new pistons, what’s the best way to do this?
If any form of model is provided (old piston, mold, cylinder head or 3D CAD model) for manufacturing new pistons, please make sure you take the following steps to ensure a proper sample is received:
If sending a piston sample, make sure it is clean and piston sample needs to be the least damaged out of the set, remove all rings, locks and wristpins.
If you are sending a Mold from cylinder head this mold needs to be made out of a hard material (e.g. Bondo ®) and should include “X” and “Y” centerlines (representing the bore CL) and backside of mold needs to be completely flat.
If sending a Cylinder head include gasket, valves, spark plug, dowel pins (if possible) and please remove valve springs. CAD 3D models are also an excellent source of information and often times more convenient, talk to your CP-Carrillo salesman for the appropriate file type. For any other types of models/samples please talk to your CP-Carrillo salesman for proper instructions before sending samples.
Q: I broke a ring during the install, can I just use OEM rings with this piston?
No, OEM rings will not fit; you would have to get another CP ring set.
Q: How much ring end gap should I run? (Answered on pages 2 & 3)
The required ring end gap varies for each application. A spec sheet/ installation sheet is included with piston and ring orders to help you determine the proper ring end gap. Click here to download the form. If you have further questions, please contact our technical sales department at 949-567-9000
Q: How much lift will your piston take?
This value depends on the engine and piston part number. CP-CARRILLO and BULLET Pistons are designed with valve pocket depths to fit most popular camshafts. We strongly recommend checking your piston to valve clearance during assembly.
Q: How long does it take to make Custom Pistons?
It depends on the level of customization. We can make custom pistons in as short as 3 days, but the engineering part can take longer. Custom piston turnaround can vary at different times of the year. We do offer an expedite service for rush jobs but you’ll want to contact your distributor/engine builder for further information. Please keep in mind that certain operations/features must be sent out for processing and CP/Carrillo cannot be held responsible in those circumstances.
Q: How do I request a catalog?
Send your name, mailing address, phone number and indicate which catalog type you like (Automotive/Marine or Powersport) you'd like to receive to sales@cp-carrillo.com or call 949-567-9000 and we are happy to send you one.
Q: How do I know my piston to wall clearance, and where do I get the measurement? (Answered in question: “Piston to wall reference chart for different bore types.”)
Each CP-CARRILLO and BULLET Series Piston kits include a piston spec sheet with a piston to wall clearance recommendation. Always measure CP-CARRILLO and BULLET Series Pistons at the recommended gauge point, usually .500" up from the bottom of the skirt or where otherwise indicated on the spec sheet. Subtract this dimension from your finished bore size to determine your piston-to- wall clearance. If you have further questions, please contact our technical sales department at 949-567- 9000
Q: How do I identify Tops, 2nds and oil rings?
See figure 1. Assuming your top and second rings are of different thicknesses you can simply measureyour rings and compare them to the groove dimensions. (SEE DRAWING) In instances where the top and second rings are of the same thickness the top ring will generally be of a shiny silver/copper color whereas the second ring will be of a dark grey or black coloring. Both rings will normally be marked with a dot(.), number, or letter that will aid in determining which side of the ring will face up toward the dome of the piston.
If the rings don’t have a dot or letter to mark “up”, check the ID of the ring and they should be beveled. The inner beveled edge of the top ring will face up towards the cylinder head, and the inner beveled edge of the second ring will face down towards the crank.
Additionally, some second rings will have a tapered hook groove on the OD. This hooked edge will face downward as its function is to scrape oil back down into the crank case. See Figure 4
In the rare instance that you receive a ring with no designation, though it could mean the ring manufacturer has determined that it will work effectively either way, we recommend that you contact us for clarification.
All of our oil rings for 4-stroke applications utilize a 3-piece design which consists of two thin oil rings separated by an expander (wavy) ring.
PLEASE NOTE: DO NOT ALTER YOUR EXPANDER. Oil ring gap specifications are for the top and bottom rails only! Oil ring expanders are designed to butt against each other and when installed along with the rails allow the ring to have the correct tension when seated in the cylinder.
You may also have a piston that requires the use of a rail support, that rail will have a dimple to prevent rotation.
Q: How do I identify my CP-CARRILLO or BULLET Pistons?
How do I identify my CP-CARRILLO or BULLET Pistons?
Q: How do I cut ring grooves?
You don’t, we do. Attempting to alter the ring groove(s) of your CP piston could severely compromise the integrity of the part. The good news - if you have the correct rings and your piston is in good condition there should be no reason to alter the ring grooves.
Q: How do I become a dealer?
If you are interested in becoming a dealer, please complete a dealer application form located here. Email completed to sales@cp-carrillo.com or fax 949-567-9010
Q: Do you have a minimum quantity of pistons I need to buy?
While our custom parts are generally made in a 4 piece minimum order, shelf parts may be purchased as singles. We also stock replacement hardware for all of our shelf parts and most customs.
Q: Can I purchase rings for your pistons?
CP-CARRILLO stocks a complete line of piston rings for your shelf and custom piston orders. All BULLET Series and CP-CARRILLO Sport Compact shelf piston kits include rings. Most CP-CARRILLO Powersports piston kits include rings as well.
Q: Can I order direct?
We don’t sell retail, but we have a list of established distributors that stock and advertise our products on our website.
Q: Are all your pistons forged?
Yes all of our parts all are forged. All CP-CARRILLO and BULLET Series pistons are forged for maximum strength and durability. We predominantly use 2618-T61 and some 4032.
4032 is a high silica (glass sand) content material that has good scuff resistance and allows tighter piston to wall clearances, however this is at the expense of strength. The greater the silica content, the more brittle the material, so 4032 does not lend itself well to high cyl. pressure applications such as those found in Super charged, Turbo charged, or Nitrous Oxide applications, with relatively light piston weights. 4032 has been used in some low boost applications in OEM and in some high boost diesel applications, but the pistons are much thicker and heavier than there 2618 counter parts, in an effort to keep them from failing. 4032 is also more expensive to machine, because it wears out tooling quicker. 2618-T61 on the other hand is a low silica content material, so it is more ductile/forgiving, so it is the material predominately used in high cylinder pressure applications. However, 2618 does require more cylinder to wall clearance because of the lack of silica and it reduces anti-scuffing qualities.
Frequently Asked Questions - Rods
Q: Why do we Rockwell each connecting rod?
Q: Why do we Magnaflux each connecting rod at least twice?
Q: Why are CP-Carrillo rods made from a forging?
Q: Why are CP-Carrillo connecting rods Shotpeened?
Q: What is the process that makes CP-Carrillo different from the mainstream parts?
Q: What is the difference between WMC and CARR Fasteners?
Q: What is Carrilloy
Q: What is a Spec Card?
Q: What is a CP-Carrillo Connecting rod
Q: Useful tips for Fastener Installation: Torque vs Stretch
Each CP-Carrillo fastener design is based on a known yield load. During linear stretch of the bolt this load should never be reached. The recommended stretch value is 80% of yield load calculated in a tension – torque diagram.
Torque figures are the more commonly used method for tightening fasteners, however this is not CP- Carrillo’s preferred method and we will explain why: Torque is affected by numerous variables, all of which can alter the true preload figure you are trying to attain. Particularly, the lube utilized, the condition of the threads, the spot face, dimensional integrity, as well as other variables have an effect. Nearly all of these elements are alleviated if the assembler uses a “stretch” method. CP-Carrillo found that the consistency of high quality fasteners offers the least deviation when using the stretch method, with the result that the fastener will exhibit proper preload using designated stretch.
Q: Truth about Horsepower
Q: Support
Q: Quality Assurance
Q: How do I know if I have a CP-Carrillo rod?
Q: Do you sell a Bolt Stretch Gauge?
Q: Do you offer a Reconditioning Service?
Q: Do I need to use CP-Carrillo Lube when installing my connecting rod?
Q: Can I buy a spare connecting rod?
Q: Are CP-Carrillo rods heat treated?
MAP Policy
Q: MAP Policy
Q: CP-Carrillo's MAP Policy Guidelines
Q: Internet Site Pricing
Q: Price Mark-Outs
Q: Pricing Statements
Q: Free Offers Associated with CP-CARRILLO Products
Q: Price Matching Policies
Q: Bundles
Q: Failure to comply with our MAP Policy
- Pricing status
- Advertising or marketing reimbursement, co-op, or other CP-CARRILLO funds.
- Reseller representative sales incentives (i.e., SPIFs, EZbucks or other additional sales contests or promotions).
- Ability to receive special pricing.
Q: CP-CARRILLO MAP Policy as of January 2010
- Automotive - 5% above Dealer Pricing
- Powersports - 5% below Dealer/Retail Pricing
Terms and Conditions
Q: Shipping
Q: Return Policy
Q: Payment Options
We accept Cashiers Check, Company Check (Upon Approval), Visa and Master Card. Initial custom orders require a 50% deposit prior to order processing. Acceptable methods of payment for international orders may be made by credit card or by wire transfer. Please ask your sales representative for details. All orders will be charged the applicable sales tax, unless a completed resale card is submitted and on file. A $30 fee will be charged for each returned check. A 1.5% per month finance charge will apply for all balances over 30 days.
Q: Notice
Q: Guarantee
Q: Quality & Environmental Policy
Q: Engine Assembly & Modification
Rings
Q: What is the difference between CP-CARRILLO and BULLET Series Pistons?
Both CP-CARRILLO and BULLET are high quality forged pistons, made from 2618-T61 Alloy. CP-Carrillo pistons are designed for high performance racing engines and are available for many "race specific" applications. Additionally, CP-Carrillo can be custom made in as little as 3 days to your specification. BULLET Series Pistons are large production runs on centralized manufacturing cells made from dedicated “Bullet” forgings. An application specific forging, as well as manufacturing in larger quantities reduces machining time. We pass the savings on to you, offering a more economically priced part, made on the same machines as a traditional CP!
In addition, the BULLET Series features a quality 1.2mm, 1.5mm, 3.0mm ring package and includes Chromoloy wrist pins with wirelocks. The 1.2mm carbon steel nitrided top ring is extremely durable and offers reduced friction over 1.5mm and 1/16" top rings. A 1.5mm Napier (hooked face) 2nd ring is used to improve oil control over conventional taper-faced rings.
Q: What do we recommend for Ring Honing?
For use with our CPN and CPN2 piston rings, we recommend plateau honing with a cylinder bore cross hatch angle of 35-40 degrees.>/p>
To reach this roughness, the manufacturers of honing machines and accessories recommend using for a gray cast iron engine block and Nikasil cylinders.
- Conventional stones #220 - #280 grit or
- Diamond stones #325 - #550 grit
After honing with either the conventional or diamond stone, the same manufacturers suggest to finish your honing by smoothing the surface with a fine grit conventional abrasive (#400 - #600 grit) or to sweep the bores with a flexible brush or a nylon bristle plateau honing tool. This is necessary to get rid of jagged peaks and folded or torn material.
Important Notice
Be sure to confirm with your honing equipment manufacturer that the recommended stone grit will produce the following Rz and Ra roughness recommendations.
Rz = 59 - 138 µ in [=1.5 – 3.5 µm] or Ra = 15 - 35 µ in [=0.4 – 0.9 µm]Please click here to download "Cylinder Honing Recommendations" (pdf - 71KB)
The following are guidelines for ring installation. Certain applications may require different clearances. Consult the enclosed charts and diagrams before installing rings.
Please click here to download "Ring Installation Instructions" (pdf - 300KB)
Q: Ring end gaps
Due to the wide variance of expansion rates typical of power adders (nitrous, turbos, etc.), air cooled versus water cooled, marine applications, etc., it can be difficult or impossible to give ring end gap recommendations that will be accurate across the board. Please be aware that the information provided is only a guideline and that any concerns should be addressed with your engine builder. All information is provided in inches of ring gap per inch of bore. EXAMPLE: A recommended ring gap of .0040 per inch on a motor with a 4.000 inch bore would yield a ring end gap of .016 inches as .0040 x 4.000 = .016
DOMESTIC AUTOMOTIVE: Normally Aspirated (no power adders) up to 600hp.
- Top Ring = .0045 - .0050 per inch of bore
- Second Ring = .0050 -.0055
- Oil Rings – Actual gap = .015-.050
DOMESTIC AUTOMOTIVE: Normally Aspirated over 600hp and turbo/nitrous applications below 750hp.
- Top Ring = .0050 - .0055
- Second Ring = .0055 - .0060
- Oil Rings – Actual Gap = .015 -.050
DOMESTIC AUTOMOTIVE: Turbo/Nitrous applications above 750hp.
- Top Ring = .0060 - .0070
- Second Ring = .0070 - .0080
- Oil Ring – Actual Gap = .015 - .050
SPORT COMPACT: Normally Aspirated to 300hp
- Top Ring = .0040 - .0050
- Second Ring = .0045 - .0055
- Oil Ring – Actual Gap = .015 -.050
SPORT COMPACT: Turbo/Nitrous applications to 450 - 750hp
- Top Ring = .0050 - .0055
- Second Ring = .0055 - .0060
- Oil Ring – Actual Gap = .015 - .050
POWERSPORTS: Normally Aspirated
- Top Ring = .0040 -.0045
- Second Ring = .0045 - .0050
- Oil Ring – Actual Gap = .015 - .050
POWERSPORTS: Turbo/Nitrous applications
- Top Ring = .0045 - .0050
- Second Ring = .0050-.0055
- Oil Ring – Actual Gap = .015 -.050
Q: My ring pack has 3 rings, but my piston only has 2 ring grooves. Did I get the wrong ring pack? Or was the piston made incorrectly?
Neither. What you have is a 2-ring piston designed to utilize the top and oil rings ONLY. Simply throw away your second ring and install as normal. NOTE: If you see a V-shaped groove below the top ring groove, that’s actually an Accumulator Groove and you can’t put a ring in it.
Q: I broke a ring during the install, can I just use OEM rings with this piston?
No, OEM rings will not fit; you would have to get another CP ring set.
Q: How do I identify Tops, 2nds and oil rings?
See figure 1. Assuming your top and second rings are of different thicknesses you can simply measureyour rings and compare them to the groove dimensions. (SEE DRAWING) In instances where the top and second rings are of the same thickness the top ring will generally be of a shiny silver/copper color whereas the second ring will be of a dark grey or black coloring. Both rings will normally be marked with a dot(.), number, or letter that will aid in determining which side of the ring will face up toward the dome of the piston.
If the rings don’t have a dot or letter to mark “up”, check the ID of the ring and they should be beveled. The inner beveled edge of the top ring will face up towards the cylinder head, and the inner beveled edge of the second ring will face down towards the crank.
Additionally, some second rings will have a tapered hook groove on the OD. This hooked edge will face downward as its function is to scrape oil back down into the crank case. See Figure 4
In the rare instance that you receive a ring with no designation, though it could mean the ring manufacturer has determined that it will work effectively either way, we recommend that you contact us for clarification.
All of our oil rings for 4-stroke applications utilize a 3-piece design which consists of two thin oil rings separated by an expander (wavy) ring.
PLEASE NOTE: DO NOT ALTER YOUR EXPANDER. Oil ring gap specifications are for the top and bottom rails only! Oil ring expanders are designed to butt against each other and when installed along with the rails allow the ring to have the correct tension when seated in the cylinder.
You may also have a piston that requires the use of a rail support, that rail will have a dimple to prevent rotation.
Q: How do I cut ring grooves?
You don’t, we do. Attempting to alter the ring groove(s) of your CP piston could severely compromise the integrity of the part. The good news - if you have the correct rings and your piston is in good condition there should be no reason to alter the ring grooves.