Ring Material: Ductile Damper, and Flexplate Specs.- Main Bearings: King MB557SI
- Rod Bearings: King CR807SI
- Balance:In House on CWT balancer.
- Damper: Pro-Racebrand Pro-Sport Series SFI 6.61
- Flexplate: Heavy Duty168 tooth or 153 tooth.Manual Trans. flywheels available in our Upgrades category.
Compression Ratio Chart
The calculations below assume your pistons are at zero deck. Let's say your compression calculates out to be 10.50:1 for example based on having the pistons at zero deck (flush with the deck), but your pistons were going to be .005 in the hole, then the comp. ratio would only drop to 10.36, and if left .010 in the hole, then it would drop to approx. 10.22 We do recommend having your block decked to allow the piston to set anywhere from flush (zero) to .005 in the hole for optimal performance. We used a 4.125 head gasket diameter, and a .040 head gasket thickness in our calculations to come up with our comp. ratio values.
We have highlighted in red the compression ratio for the bore size and piston volume of this assembly using several popular combustion chamber sizes.
Part Number
Cylinder Head Volume
58cc
64cc
68cc
72cc
383 Assembly
Static Compression Ratio
4.030 Bore
12.00
11.15
10.65
10.19
4.040 Bore
12.05
11.20
10.69
10.24
4.060 Bore
12.16
11.30
10.79
10.33
Listed below is a complete breakdown of all the parts that are included in this assembly.WISECO FULLY FORGED PISTONS, RATED AT 800+ HP. WISECO PISTONS ARE 100% MANUFACTURED IN THE USA. THEY ARE ONEOF THE HIGHEST RATED PISTON BUILDERS IN THE COUNTRY.Our custom made Wiseco pistons are rated very high in the street/strip performance industry. Wiseco normally offer several grades of pistons, starting with the lower grade Pro-Tru Street version made with 4032 forged alloy. The next level up would be the professional series that are much more expensive and made from 2618 aircraft alloy and have fully machined crowns rather than the as cast crowns that are on the Pro-Tru series. Our Wiseco pistons are custom made for us, and have both of these premium features, 2618 Alloy, and fully machined crowns. All premium grade forged pistons on the market have these two unique features and usually cost around $800-$1100 per set.
We prefer the 2618 alloy over the lower cost 4032 alloy. The 4032 alloy may fragment from the effects of detonation and if this happens, it can be very destructive to the engine.Those types of pistons are fine for stock or mild engine builds, but should never be used in carbureted engines built to high horse power levels.The forged 2618 alloy piston is much more resistant to the effects of detonation and heat.
We have built approximately 8000 engines using the Wiseco pistons over the past 10 years. The engines have been for street rod and strip use. We have seen no problems, nor have there been any complaints. They are an excellent product in every respect.Important note
Many customers have asked us what size they should bore their block at to allow for a proper piston to wall clearance. The required clearance is built into the piston already. For example if these pistons show a given size such as 4.030 then that is exactly what you will bore the block to. The actual size of the pistons when measured at the skirt, 1/2 inch above the tang will show to be approx. 4.026. The needed clearance is built in. Should you be using these pistons in a marine app. where the boat receives it's water from the lake, then an additional 1.5-2.0 thous. would be added to your final bore size, and some forced induction apps may also require a slight increase in bore size.
These pistons are totally suitable for use with mid level nitrous or blower setups. Extreme level builds that are making hp numbers in the 1000 hp range will require a set of custom made extreme duty pistons
Our Wiseco Forged pistons are custom designed with an increase in compression height. This has many advantages. Here are a few facts about compression height and deck height.
Our custom made pistons have a compression height that is .010 taller on bbc pistons, and .015 taller on sbc pistons, as compared to most all of the catalog pistons on the market. We find this to be a very valuable feature.
Since our pistons sit at a taller than normal compression height, you will only have to remove approx. .005-.010 off the deck surface of a virgin block to achieve a zero deck (flush with the deck surface). This maintains the deck's thickness, making it much stronger than a block that has been cut down .025. The engine will also run a bit cooler with a thicker deck. It's well known that the deck dissipates much of the built up heat an engine generates. This also allows for future deck re-surfacing without compromising the integrity of the block. Most all catalog pistons on the market require cutting the deck surface around .025 to achieve a zero deck. A zero deck is very important as it keeps the quench/squish zone at or near an optimal .040 distance. Be sure and let your machine shop know what the compression height is on these pistons before they machine your deck surface.
You may have noticed that our Wiseco custom made forged pistons are referred to as Racing Pistons on the package. This does not mean that the pistons are for racing only. This is a generic term, referring to their ability to be used in high performance applications as well as for street rod use. These pistons are perfectly designed for use on the street, as well as for medium to upper level drag racing.The picture below is a file photo of our Wiseco pistons. The picture was taken with a bright flash and appears to have enhanced the machine marks. These marks are actually barely visible with the naked eye.
Scat Crankshaft.
The picture below is a generic file photo of a Scat crankshaft. You will receive the correct model packaged in the original Scat box.
Some of the benefits of the Scat crankshaft supplied with this assembly:
The material used in this crankshaft is manufactured from an exclusive Space Age material that was designed for high strength and fatigue resistance. The Scat cranks are 25% stronger than stock OEM cast cranks andare the best valueyou will ever find. The Scat crankshafts are the best wayto build a strong bottom end for, street rods, dirt and circle track racing, and drag strip racing. This crank is suitable for use up to approx. 500-525 hp.
We recommend that you check the thrust clearance on the crank before assembling the engine. This is recommended on any crankshaft, regardless of brand or cost. Also be sure to check your main and rod journal size.
Scat connecting rods.
Genuine Scat Competition Bushed Rods with ARP 2000 12 point 7/16" cap screws are now used in all of our rotating assemblies and 383 Stroker engines.
As seen the in close-up picture below, Scat Competition rods have a very solid build quality.
The quality and design of the Scat Competition rods is unsurpassed by any of the lower cost conventional I beam rods on the market.
The Scat Pro-Comp extreme duty I-beam rods should not be mistaken for ProComp rods. These rods are made exclusively by Scat, and have nothing to do with the ProComp company. The critical sizing and installation of the ARP 2000 cap screws is performed on a Sunnen machine in the USA by Scat Industries. These rods are excellent for those wanting the extra security offered by a rod with 7/16 ARP 2000 rod bolts.
If you do a search on the Scat Pro-Comp rods, you will find a vast amount of info on many car forums. All of the info is 100% positive. These rods are run in engines that not only produce high horsepower levels, but also run at continuous RPM. Notice the general appearance in the pictures. These rods do look impressive. The style is reminiscent of an Oliver Pro Series rod.
The fact that these rods are incredibly strong and well made, coupled with the fact they are light weight and offer better cam clearance than any H-Beam rod on the market, made it an easy decision to use themin all of our high horsepower street/strip engines.
Genuine ARP 2000 rod bolts, aka cap screws.
All of our sbc engines use the ARP 2000 rod bolts. The rod bolts are most likely to fail under hard use, more so than the rod itself. When a rod bolt fails during high RPM, total engine destruction is usually the result. The ARP-2000 rod bolts are superior to the more common ARP 8740 bolts, in our very strong opinion. Those who run hard always use the ARP-2000 rod bolts in their rods. The ARP-2000 rod bolts also torque at a higher number, and this increased clamping force is also a factor in keeping the rod cap from "walking" as it's referred to. It is this minute repetitive amount of cap walk that over time stresses the rod bolt and often leads to a major engine failure.
We have noticed some sellers using generic rods and crankshafts in their rotating assemblies. These non-branded (no-name) rods and cranks are often poor quality in many ways. You will notice many sellers fail to mention the actual brand of these products. Upon further investigation, you will find such parts not to be a branded name product. They may label these parts with a name, but one that is totally unrecognizable in the industry. Our experience in years past with such rods and cranks has been disappointing, to say the least. Failures of such critical parts in your engine may result incatastrophic damage. Machine shops are sometimes able to correct some of the problems with these low quality rods and cranks, but at great expense to the customer. As for the questionable alloy these items may be produced from and the potentially incorrect heat treating methods used, little can be done to verify this and nothing can be done to correct it. As you may have noticed, this is why we specify the name, brand, and series of every part used in our assemblies.
Many of the inferior "no-name" rods on the market will also have "no-name" rod bolts in them. We have seen these bolts before, and they are very low quality. They don't have ARP's rolled thread design, and they don't torque down with the same characteristics as a genuine ARP bolt. It's not just a matter of having a different brand bolt in the rods; these bolts are low quality in many ways. They have been known to fail in engines to a much greater degree than a high quality rod bolt, and this failure usually causes catastrophic damage in the engine. Beware of rods that don't mention the rod bolt brand. As far as we're concerned, ARP bolts are the only brand we would ever use or accept in a set of rods.
Before the engine is assembled, we strongly suggest checking the rods on a Sunnen machine for sizing on both ends. We recommend this with any rod regardless of cost or brand. It is not uncommon to find some of the rods requiring a slight bump through the hone for perfection in sizing and roundness. We also offer this assembly with a proofed set of rods. This is an excellent choice for those wanting to build the engine on their own.
MAHLE or HASTINS RINGS DEPENDING ON AVAILABILITY,KING OR FEDERAL MOGAL, DEPENDING ON AVAILABILITY MAIN AND ROD BEARINGSINCLUDED.
Pro-Sport harmonic SFI damper, 6.61 diameter, included.
The SFI Pro-Sport damper Offers an extreme level of safety against breakage, and is very resistant against slippage of the elastomer damping material. SFI dampers are not only made from a better grade of steel, they are also constructed differently and have a much better appearance. They usually last much longer than a non-SFI damper. Many drag strips require this on engines producing high horse power levels. The SFI certification is laser etched into the side. Damper failure rates are much higher on engines using a non-sfi damper coupled with hp ratings exceeding 450 and turn 5600 rpm or higher.
We have noticed others using a low grade knockoff brand damper/balancer, and we have encountered them in the past. They are substandard in appearance, and are often out of spec.The timing marks were also poorly marked on some of the balancers we have come across.You don't want a balancer coming off or one that is improperly weighted. Another problem with low grade dampers is the elastomer bonding can lose its adherence to the inner and outer structure. This problem is referred to as a slipped damper. We have only encountered this once in 10 years with the Pro-Race brand dampers.
We know of severalcompetitors including these balancers with rotating assemblies. The Pro-Sport SFI is far superior to most any we have ever seen. They were once known as a knockoff product, and have become one the best values on the market, without comprising quality whatsoever.
HEAVY DUTY FLEXPLATE INCLUDED.
HEAVY DUTY FLEXPLATE. This flexplate will resist cracking. One good telltalein identifying a low quality flexplate is the lack of welding on eachside where the plate mates to the ring gear. They usually have a palegrey color to them, as they are not coated, and will rust quickly.Oursarewelded on both sides, and are much thicker than an OE plate, and are either zinc dichromate orblack powder coated. We would never use the thinner OE style plate on anassembly like this. It is very important to let us know the tooth count that you require to accommodate your transmission. Some bell housings will not allow the use of a 168 tooth flexplate, and will require a 153 tooth size. We usually have both available at no extra cost.
WARNING: The crank has a dowel pin installed in it. You must align the flexplate or flywheel to the dowel pin. The assembly was balanced with this pin installed.
We offer premium grade Ram brand SFI Billet Steel flywheels for manual transmission use at an additional cost. See our other listings. This assembly includes a flexplate for automatic transmission use at no additional cost.
When choosing a flywheel for manual transmission use, be sure to know what tooth count you need. There are two sizes available, and it is of the utmost importance to select the flywheel that is correct for this assembly. There are several factors that must be addressed when choosing your correct flywheel. The tooth count must be correct. This is very important. There are two sizes available, and it is the bellhousing size on the transmission that determines this. Another important factor is if the assembly your purchasing is internally balanced often referred to as neutral balanced or if it is an externally balanced assembly, often referred to as externally balanced. All of our assembly ads will have this information in them. Big block and small block engines will also have a different bolt pattern in most cases. To sum it up, there are three important factors to look for when selecting the correct flywheel, tooth count, int. or ext bal. and whether or not you have a big block or small block engine. The Ram brand flywheels we offer are very high quality.
Our CWT 5500 Balancer.
We do our own balancing with our new state of the art CWT 5500 Series balancers. The CWT 5500 is the ultimate for precision balancing.We now have three of these in our machine shop.We consider this machine to be highly advanced compared to the Hines balancer we once used.We balance every rotating assembly we sell within 2 grams or less at no extra charge. A balance sheet is included with your assembly.
Three CWT balance machines under one roof is a rare sight.
Our crew wrapping up for the day. Pardon the mess.
Rust warning.
If you are going to store your rotating assembly or short block kit for any length of time, it is very important that you protect these parts by spraying a light coat of rust preventive substance on all bare metal parts. This is especially important for those storing these parts in a high moisture or humid environment. Very light surface rust is easily removable and will cause no harm, but heavy rust can damage these parts and be very costly to fix.
Our thoughts on what the competition has to offer.
Many rotating assemblies we see on the market are not using the most suitable parts. We hope you can value the fact that we have put together an above average assembly. The failure rate with the parts used in our assembly is near non-existent. These are the same parts we use in our engine program.It was through trial and error in years past that taught us where to draw the line with low cost parts. We are out-priced by many others selling assemblies that include parts that have high failure rates. Many of these parts also pose a great problem with assembly due to the fact they require additional machining and can end up costing you a great deal more money and time. If you're going to have a machine shop build your engine, we strongly advise you get an opinion from them on the parts you're going to be bringing to them. Rest assured they will find no problem with the combination and quality of our parts. We have also seen sellers offering parts that are not compatible with what most people are building. The low grade dampers and flexplates are often a problem. Another area of concern would be balancing. Not sure how much attention these sellers are giving the assembly in this area. We spend up to two hours balancing an assembly, and using the very best up to date CWT balancing equipment on the market. If the assembly is not balanced properly, it will cost you horse power, and it can damage the bearings in the engine, not to mention there is nothing worse than an engine that lacks a smooth feel and sound when ran in the upper rpm range.
We offer this assembly with selected upgrades. Listed below are some of the most requested ones. Many not only improve performance, but further enhance the reliability and longevity of your engine, along with resale value.
Note:The upgrade prices below are subject to change. Refer to the actual upgrade listing for the exact price of these upgrades. The changes are usually very small if any.
SFI Certified Flexplate:This is a very low cost upgrade and may be required when racing your car at certain tracks. The flexplate that comes with this assembly is a heavy duty plate, but the SFI certified plate is one step up in quality and safety. This SFI plate is made in North America. We noticed these have much less run-out and warpage than we see with many other plates on the market. Plates with too much run-out and warpage can cause a host of problems for your transmission and starter, and affect balancing. The low cost to upgrade to this is well worth it in our opinion.
Cost of this upgrade is$24.50We have this upgrade featured in our other listings. You can see this and other upgrade options in our store under the "UPGRADES" category, or simply do a search with the key word, "Upgrade" in the search bar when shopping in our store. Before you finalize your purchase of this assembly you may add any of these upgrades to your shopping cart.
Crank polishing:Extends bearing life, reduces oil temp, frees up a slight amount of average horsepower. This is a very low cost upgrade, and in the world of mass production, most cranks do not come with a true polished finish. This is why most machine shops have a machine to do this. The difference is dramatic between a crank right out of the box and one that we have polished. Bearing companies claim that cranks that have better finishes on the journals will survive the break-in better, and have much longer bearing life. We do a two-step process and bring the RA numbers down in the single digit range. We have the most advanced crank polishing machine on the market.
Cost for the crank polishing upgrade is$39.50We have this upgrade featured in our other listings. You can see this and other upgrade options in our store under the "UPGRADES" category, or simply do a search with the key word, "Upgrade" in the search bar when shopping in our store. Before you finalize your purchase of this assembly you may add any of these upgrades to your shopping cart.
