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Price: $7650.00
SBC CHEVYSTAGE 4.0 HYDRAULICROLLER CAM421ENGINE550 HPSTREET ROD SETUP.RUNS ON PUMP GAS.This engine is fully assembled from intake to oil pan.
Important note.
Our eBay user id is:skipwhite, and our eBay store name is whiteperformance1. You may have noticed other sellers using a similar name offering similar products. These other sellers have capitalized on our name as we see it, and many customers searching for us will inadvertently find them, thinking we are one in the same company. There is only one \"Skip White.\" We are the original premier eBay seller under this name since approximately 2003. We have no other eBay names, nor are we associated with any other company regardless of the similarity in the name or location. Our official company name is Skip White Performance. Please see the article in the lower part of this ad for a more detailed explanation
DARTSHP BLOCK WITH SPLAYED MAIN CAPS.FORGEDWISECOPISTONS, SCAT3.875STROKE CRANK, AND6.0SCAT RODS.NKBALUMINUM HEADS.
FULLY ASSEMBLED FROM INTAKE TO OILPAN.
- DART SHP BLOCK WITHSPLAYEDMAIN CAPS. COMMONLY USED IN ENGINES BUILT TO 800+ HORSEPOWER.
- NKBALUMINUM ALLOY HEADS.
- HOWARDS ROLLER CAM ANDTIE BAR STREET STRIP ROLLER LIFTERS. A CUT ABOVE THE OTHERS.
- SA GEARBILLETTIMING SET WITH TORRINGTON BEARING AND ROLON CHAIN 9 KEYWAY. TOP OF THE LINE.
- COMPALUMINUM ROLLERROCKERS 1.5 OR 1.6 RATIO.
- SCAT 4340 FORGED CRANKSHAFT, CLEVITE HP BEARINGS. BALANCED ON OUR CWT BALANCER TO BELOW 2 GRAMS.
- SCATCOMPETITION RODS WITH ARP8740 7/16 CAP SCREWS.
-WISECOPREMIUM FORGED PISTONS. 800+HP RATED.
- MELLINGM-SELECTSERIES OIL PUMP WITH M-SELECT DRIVE ROD.
-CHAMPOIL PAN WITH OIL CONTROL SYSTEM.
-PRO-RACE BRANDSFIDAMPER.
- TWO YEAR WARRANTY.
This engine is designed for street/strip use. Pump gas friendly.
See our other listings for the fully dressed out turn-key version.
Two year warranty, see details below.
This engine is designed to have a high level of drivability, or street manners. Cams #3 and #4 are our favorites for offering exceptional low end and mid range performance plus max drivability without needing to deepen final gearing or the need for a high stall speed torque converter.
If you choose to go with the Hurricane single plane intake and the first choice cam with 1.6 rockers, it will bring the hp numbers up to approx.550. We do not recommend the single plane intake combined with cam choice 1 on any car that is over approx 3,200 lbs and/or cars with a steep (tall) final gear.
Please read the cam info provided below on the four cam choices before purchasing this engine. It is very important that you choose the correct cam and intake for your car and its intended purpose.
Here are a few good reasons why we think the 421 engine is a better choice than the 383 or 406 engine.
1. The 421 willaccelerate most medium to heavy cars dramatically quicker than the common 383\'s and 350\'s on the market. The main difference between a 421 and the 383 is that the 421 torque comes in much lower. The difference is so dramatic that you would estimate the engine to have a much higher horsepower rating than it actually has. If you\'re not familiar with the 421 engine, do an internetsearch on SBC 421 vs 383 or 406, and you will be convinced of the difference. There is no inherent weakness in the 421 engine when using a Dart high performance block. These engines are built to last and these blocks have plenty of room for additional rebuilds if needed. All parts used have much higher hp ratings than this engine is producing.
2. The exhaust note that this engine produces is much deeper than that of any of the smaller cubic inch engines on the market. The difference is dramatic to say the least.
3. Thisengine can be installed in medium to heavier cars without killing acceleration, having todeepen the final gear, and needinga huge stall converter. Thisengine will accelerate a 3600 lb or heavier car much better than the 383 or 350.
4. Very low maintenance, decent drivability, yet costing only slightly more than building a 383 or 406 street rod engine. Horsepower will vary, depending on cam and intake choice. You have up to four different cams to choose from, and two styles of intake manifolds plus two rocker ratios.
5. Longevity, reliability and low maintenance.You don\'t have toturn the engine to a critical rpm range to produce its max hp output. There is nothingunsafeaboutrunningan enginethat\'s as well built as this up to approx. 6,200 rpm. Our NKB aluminum heads use very high quality hardware. The new Dart Super High Performance block would be indestructible if built to the power rating of this engine. The Wiseco Racing pistons are rated at 800+hp. The protection against detonation is at its highest with these type pistons.
6. Should you ever decide to sell your car,theresale value of a street rod with a 421 engine is very desirablecompared to those running 383\'s. No 350, 383 or 406 can be built up to the level of a 421 while running pump gas with the same compression. The power and torque numbers down low in the rpm band are what make this such an incredible engine, compared to the smaller engines.
We do a full test run on every engine we build on a test mule. The engine is run for two intervals of 15 minutes each, and every possible issue is addressed. When you install the engine, you must verify that the timing is set at the correct value, and the fuel to air ratio must be verified. We also include an engine stand like the one pictured, wheels included, and an engine lift plate.
As of 9/15/2013 we completed installation of our brand new Super Flow 902S dyno. In the past, we outsourced our dyno work. We were unable to do the research and development we truly wanted, and this prompted us to make the $105,000 investment. It\'s been one of the best investments we have ever made. Every aspect of our engines can now be monitored, calibrated, and tuned. Best of all, we can now see what combos generate the best power, with consideration to drivability.
One thing we have noticed is that the de-tuned engines with different cam and intake combos certainly do have less top end horse power than expected, but the torque increase in the low rpm range is much greater than in the higher horsepower setup. This increase in torque down low is what you want if you\'re sporting around on the street, rather than all out racing. The de-tuned version of this engine will also allow you to set the car up closer to stock and increase drivability to a very high degree. Throttle response is also noticeably better.
The build sheet is as follows:
Pictured below is the new Dart SHP block. This block is the absolute ultimate in quality, durability, and value.We are now using the Competition Series PBM valves in all of our engines. These are considered a high end valve. These valves have an undercut and backcut feature.
The backcut feature reduces valve weight by an average of 12.5 grams per valve.This weight reduction of approx. 208 grams off the complete set of valves hasa monumental effect on acceleration, deceleration, and valve train life.It may be difficult to understand how this works, but rest assured, this is a hugereduction.The valve spring compression and reboundaction will remain stable for a much longer time running lighter weight valves, as well as reducing valve float.
The backcut feature is not be mistaken for undercut. These valves have both features. Backcutting is an additionalradius, but located on the head of the valve to increase the flow numbers and reduce valve weight. The flow increase is approx. 3-6 points on the flow bench, and possibly more, depending on the initial flow rate of the heads.
According to one of our machinists who built Winston Cup engines for 15 years, the exhaust valves had an additional radius cut on the outermost edge that allowed a better escape of the exhaust gas.This cut on the exhaust valve is in addition to the back-cut feature.The competition series are made from a much higher temp alloythan most other stainless valves. There are at least three levels of stainless valves on the market, excluding those used in very high level racing such as pro-mod. The PBM competition seriesis compared to the highest level of those three. As a final note, backcuttinga set of valves is said to improve flow in the low lift area, and this is most desirable on street rods.
Comp High Performance Dual Springs, Part Number 987-16
Our Comp springs are1.43 diameter, with an inner spring and internal damper. Others are using springs that are much smaller in diameter. Smaller diameter springs may be in the correct spring pressurezone, but they usually have a shorter life. Comp springs are made in the USA. All of our engines using the NKB heads use these springs. Spring failures are near non-existent.
COMP CAMS \"POSITIVE STOP\" VITON VALVE STEM SEALS. # 529-16Comp 10 degree machined valve locks.
We use only Comp Super10 degree machinedlocks. Our head builder noticed the low grade locks on the market fit more loosely than he felt they should, not to mention the possibility that they were made of inferior metal. He envisioned the engine being much more prone to dropping a valve at high rpm. Using these locks, we have yet to have an engine drop a valve due to a valve lock failure.
Comp Cams retainers # 75740-16 and Comp Cams ID locatorsPart number: 4771-16
Our Comp Cams retainers # 75740-16 and Comp ID locators # VTH-4771-16 are made from 4130 chromoly steel. These retainers have a perfect fit with the Comp valve locks. We have used these on all of our engines for many years, and have had zero failures.
Assembly Procedure
We hone all of the bronze valve guides with a ball berry flex hone to establish not only perfect clearance, but also a semi cross hatch finish for oil retention. We finish off with a natural bristle brush. The heads are then placed in our parts washer and cleaned with high pressure hot water, then pressure dried. Before installing the valves, we apply a heavy coat of engine assembly lube to the valve stems. The coating on the valve stems is essential to protect the bronze guides from gaulding on initial startup.
Our next step is to set the spring pressureto a predetermined pressure using a spring height checking device, most suitable for street rod use. The springs we are using allow for a near perfect seat to nose ratio. Be warned that some sellers of aftermarket heads may not be checking the installed height when assembling the heads, and may not be setting them up to the correct pressures. We have a full scale machine shop with several very knowledgeable engine builders that know and fully understand how to properly assemble a set of heads. Combine the possibility ofpoor assembly methods with incorrect or low grade hardware, and it is easy to see how failures can result.
Head gaskets are Fel Pro 1003 premium race grade series, and ARP head bolts, and rocker studs.
Howards brand are the only type of pushrod we use in our engines. Made in the USA from 4130 chromoly steel. Regular hardened pushrods will most likely flex in the engine when running above normal RPM ranges, and risk bending under high RPM. These do not have the welded ball on the end. We only use the swedged one pc. design, which is a well proven design far superior to the style many others use in engines. 4130 chromoly steel is also much stronger, and will resist flexing. When a pushrod flexes in the engine, you lose lift. Don\'t be misled by the term \"hardened,\" as this is nothing more than a stock style low cost push rod. They will flex in the engine or possibly bend permanently.
You have a choice of single or dual plane intake. The single plane intake (1st pic below) should only be used on cars that are very lightweight and have good hood clearance.
Dual Plane Intake shown below. This is a large runner dual plane intake. They make excellent mid range power.
Pictured below is the Edelbrock Performer EPS dual plane intake. If you\'re going with cam choice # 2 or 3 and require more bottom end power, we strongly recommend this intake. This intake offers incredible low end response and has excellent hood clearance for those installing this engine in a C3 Corvette with a non-cowl stock hood.
304 STAINLESS ALLEN HEAD INTAKE BOLTS ARE USED ON ALL OUR ENGINES.
We are offering four cam choices listed below in this engine. Read the specscarefully.
Cam choice # 1
Special GrindPART NUMBER: 08-000-8-12675
540/571 lift
242/248 duration
110 lobe sep.
Comp Cams SBC Xtreme EnergyStep Nose Hydraulic Roller Camshafts.
This cam is the most aggressive of the four choices listed. It will make its peak horse power at approx 6250 rpm. The idle is radical.
We recommend a stall converter of around 2750-3000. Final gearing would need to be at 373 or numerically higher. A 373 final gear is most optimal with this cam, providing the car is reasonably light. This cam does make the most horse power but will trade off bottom end throttle response and low speed cruising in the low rpm range unless your car is setup in pro-street form. The idle sound with this cam is very erratic.
You would not be able to run an overdrive trans, power brakes, or air conditioning with this cam choice. Valve train life and reliability is reduced with this cam as compared to the other choices. This would only be a concern for those wanting to drive their vehicles on long trips or with frequent use. This cam choice puts your setup nearly into the Pro-Street league.
Drivability is fair at best with this cam, unless you have a very light car, with a decent final gear.
If your car is over 3400 lbs, we strongly advise against this cam, unless you have a final gear in the 4.10 range or numerically higher. If you\'re on the fence with this cam choice and the one below, then you may want to go with this cam and keep the rocker ratio at 1.5, or go with cam choice 2 and go with a 1.6 ratio. That would put you somewhere in the middle of cam choice 1 and 2, at least in respect to valve lift.
Official Dyno report coming soon.
Important Note:If you choose cam choice 1 with the single plane intake combination, it is highly recommended that you upgrade the ignition system to an MSD Pro Billet distributor, and CDI unit. You should also upgrade the carburetor to the SS Series for optimal performance. These important upgrades are essential for improved idling and overall performance. If you do decide to use the MSD Pro Billet distributor we suggest you use the black timing degree bushingto increase the initial timingand possibly the lighter springs to control how soon the total mechanical advance comes in. You may even \"lock-out\" the distributor, depending on you cars overall setup. The CDI unit will make a huge improvement in how the engine runs at idle. Low speed cruising will be greatly improved, as well as high rpm operation. The SS carb upgrade is an all out double pumper carb, and gives the engine instant throttle response. If you choose cam choice 2 you may not require these upgrades but should consider them to enhance the performance and drivability of your engine.
Cam Choice #2
Special Grind # 33161
PART NUMBER: 08-000-8-11323
520/540 lift
236/242 duration
110 lobe sep.
Comp Cams SBC Xtreme EnergyStep Nose Hydraulic Roller Camshaft
Cam choice 2 is considered somewhat aggressive and improves drivability compared to cam choice 1. This cam will still have a lopy idle. You would require a stall converter in the 2500-2800 range.Final gearing should still be at approx. 3.73. If your car is in the 3800 lb weight range or more, we recommend cam choice 3 or 4. Hp numbers will drop with this cam, around 20-25 at the most. Combine this cam choice with the dual plane intake option and hp numbers will fall approx another 10-15, but bottom end torque is greatly improved, as well as drivability.
It is not recommended to opt for the single plane intake if your car is in the medium to heavy weight range. They do not operate as well in the lower rpm range. The low end torque with this cam comes in sooner than cam choice 1, but you must still set the car up with proper gearing and converter stall. This cam is our most popular and delivers great bottom end power and very good drivability.
You may not be able to run an overdrive trans with this setup, power brakes are a possibility. We do not recommend this cam if your going to run an A/C unit and overdrive trans. Our cam choice 3 or 4 would be much more suitable.
Official Dyno report with this cam, NKB heads, -13cc dish pistons, single plane intake, 1.5 rockers, SL 750 carburetor, and HEI distributor.
This report is with our new line of custom ground Comp Cams. Nothing short of pure magic. We\'re highly satisfied with what these new custom cams are doing in our line of street rod engines.
Official Dyno report with this cam, with a few changes. The upgraded SQ carb, same cfm, but rocker ratio was only a 1.5 and notice the outstanding numbers made with this cam. If this engine would have had the 1.6 rockers like the one above, it\'s fair to say the numbers would have been even higher. The carb upgrade is worth approx. 20hp in our opinion, and this is excellent considering the cfm size was the same. The SQ carbs are a great upgrade for the slight cost to upgrade.
Cam Choice #3
Special Grind # 11480
PART NUMBER: 08-000-8-11480
510/525 lift
230/238 duration
111 lobe sep.
Comp Cams SBC Xtreme EnergyStep Nose Hydraulic Roller Camshaft
This cam choice (3) is the perfect all around setup for those wanting excellent bottom and mid range power, while still generating decent power at the top. Horsepower rating would drop an additional 10-15 hp below the cam choice 2. Drivability and street manners would be considered excellent. Heavy cars, upwards of 3800 lbs or more, would do well with this cam choice. No need for a high rpm stall with this cam, but you would still require a stall in the 2200-2500 rpm range for optimal acceleration.
If your car is in the heavy weight range, and/or geared on the steep side and you want much better streetability, then this is the correct cam choice. You still want to keep the final gear ratio at approx. 3.20 or numerically higher. If you have an overdrive trans., then this cam, coupled with the dual plane intake, would allow the engine to cruise in overdrive with rpm in the 1950-2050 rpm range. Should you have a Turbo 350 trans, then this cam choice would allow you to run a somewhat taller final gear to allow decent highway driving in the lower rpm ranges.
You may choose 1.5 or 1.6 rockers with this cam, but we recommend the 1.5 rockers for even better low end response, especially if you plan on running an overdrive transmission. You can also expect a much longer valve train life with this cam compared to the larger cams listed above, especially with the 1.5 ratio rocker choice.
Carb size when using this cam will drop. You\'ll notice slightly better mileage and better throttle response with this carb versus the larger carbs required when running the larger cams. If your vehicle is very heavy, over 4400 lbs, then we recommend our cam choice #4.
Official Dyno Report with this cam, NKB heads, single plane intake, Brawler 750 carb, and MSD distributor.
Official Dyno Report with this cam, NKB heads, dual plane intake, Quick Fuel SQ 750 carb, and MSD distributor.
Cam choice #4
498/502 lift
220/226 duration
111 lobe sep.
Comp Cams SBC Step Nose Xtreme Energy Hydraulic Roller Camshafts.
Cam choice #4 would be an excellent choice for those with a heavy car or truck. This cam would also be the best choice for those running a 700R4 trans. Low speed cruising, running an A/C, and excellent vacuum for operating power brakes are all possible with this cam.
Great off idle power. A stall converter in the 1600-2250 range would give excellent results. Gearing could be considerably taller, allowing for much better mileage and low rpm highway cruising.
Excellent of idle power is what to expect from this cam choice.Carb size will drop once more with this cam. Possibly better mileage, and for certain, throttle response would be excellent with this cam.Valve train wear and noise would be nearly nonexistent when coupled with 1.5 or 1.6 rockers.
One more benefit of this cam choice is that we can set the engine up with a reduced compression ratio, and this would offer great protection against detonation, and also extend the life the of engine. Running mid grade fuel or even regular grade fuel becomes a possibility with the reduced compression ratio.
The information above on cam selection is not etched in stone.You could step outside these guidelines in either direction to some degree and still have very good street manners. The larger cams could possibly cross the finish line sooner in cars that are setup properly compared to the smaller choices, but the smaller cams will have a better feel in the lower to mid rpm range without all the drama of the more radical setups above.
We\'re all hungry for as much horsepower as we can get, but building an engine of a given size to higher horsepower will always require a trade off. The 383 engine offers the best of both worlds when it comes to bottom and top end power, but the bigger cams are more demanding on gearing and stall, sensitive to weight, and suffer on drivability as well as valve train wear and tear.
THE CAMS LISTED WILL COVER MOST NEEDS FOR ANY STREET ROD OR SPORT TRUCK.
Pictured below are some of our most popular valve covers. They are fabricated aluminum, and very high quality. You may select from any of the valve covers we have listed at no additional cost for your engine.The satin covers below are by far the most popular.
RETRO STYLE FINNED. OUR SECOND MOST POPULAR CHOICE.
THE RETRO FINNED VALVE COVERS CONTRAST NICELY WITH THE CHROME AND POLISHED ITEMS.
OUR RETRO STYLE TALL FINNED VALVE COVERS HAVE BECOME VERY POPULAR. YOUR CHOICE.
Timing components: SA Gear 8999T billetdouble roller timing set.
Polished Aluminum Timing Cover.