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NKB-200 ULTRA HIGH FLOW CYL. HEADS WITH STEAM HOLES FOR SBC 400, 406 ENGINES.
THE BEST FLOWING, BEST QUALITY SBC ALUMINUM HEAD ON THE MARKET FOR THE MONEY.
This sale is for a bare set of heads (2 heads).
200cc runner size, 64cc combustion chambers. Uses 2.02 1.60 valve size.
Our cylinder heads are made from AC4B alloy and tempered to T6 standards. Details about this alloy are in the lower section of this ad.
These heads can be used with outer perimeter or center bolt valve covers.
Flow chart information.
In the flowchart above, the NKB-200s are superior to the Procomp heads in flow numbers, and also edge out the Dart SHP heads on the intake side. The intake numbers are far more important than the exhaust. The overall average flow numbers on the NKB-200 heads are higher than most any brand of non cnc'd cast aluminum heads on the market. We guarantee the flow numbers to be accurate, as well as the horsepower numbers produced by them.
Most importantly, all three of these heads were tested by the same person, on the same machine, (Superflo bench 1020) using the same testing method, on the same day. These numbers show the true difference between each brand, and that's what counts.
The difference in horsepower and torque generated by these new heads is monumental compared to the Procomp heads. We offer four different cam choices for your consideration, and every combination has shown an increase of up to 50 horsepower and no less than 40 hp when coupled with the various combos. We assumed the new heads would generate a considerable increase in power, but to our surprise, they generated even more power than expected.
We tore down the heads that were on our 383 house engine and checked the guides as this was an area we are most concerned about, and found zero wear. The seats were also in perfect condition. We tested the spring pressure to see how much was lost after a brutal 80 or so dyno passes, and saw approx. 10 lbs of pressure drop on the nose, and even less on the seat, and this is to be expected.
Many of the dyno passes were run to 6500 rpm as the large cam needed 6300-6400 rpm to make peak power, and you must run past this to determine the fall off point. The super sized cam, (choice 1) was run on the heads towards the end. Considering the size of this cam, it was very impressive to see no issues with the heads or hardware. We made a good 25 passes with the big cam trying out different carb sizes, jetting, intake manifolds, timing setting, and adding the Super Sucker plate last.
Our cylinder heads are made from AC4B alloy and tempered to T6 standards. You may have heard the alloys 355 and 356 being used on many heads. The alloy used on our heads is similar but slightly different. The AC4B alloy is commonly used by automakers in Europe and Japan. Take notice of the Rm value. This value indicates the tensile strength of an alloy. As you can see, it's higher than all the other common alloys in this chart. It's no surprise as to why we have never experienced a failure of any kind with these heads. Zero failures in the casting, zero failures in the seats and guides. We have sold over 5000 pair of these heads over the past four years.
ONE YEAR WARRANTY, UNLIMITED MILEAGE.
The warranty will cover the castings and seats.
Important note from Skip White.
The results produced by these heads will vary greatly depending on the type of setup you are running. The engine combos we have dynoed are what most people use for cam and intake selection, and the results are listed below. The engines dynoed were many 383's, and several 406 and a few 421 cid engines in the 10:1 to 11.2:1 compression range. All ran on pump gas. This will give you an idea about the capabilities of these heads with combinations of cam, intake, rockers, and carb. This may also help you select the proper cam for your build.
We certainly know where to draw the line with low end products, and we continue to eliminate parts that we once accepted but that eventually had problems. Sometimes it's not that a particular product has had a problem that leads to its elimination; something better just comes along. The NKB cylinder heads are that “something better" coming along. Considering the price is only slightly higher than our former line of heads, this has to be the best value in a set of cylinder heads we have ever offered. We now use the NKB heads on all of our 350, 383, and 406 engines. The performance has been outstanding on every combination we have tried them on. In the rare event you have issues with our NKB-200 heads, the problem will be addressed. As of today (2/17/16), we have been selling the NKB heads for around 2.5 years. We have sold approximately 3500 sets, and problems have been near non-existent.
We have complete top end hardware kits available for the NKB-200 heads in our other listings. The kit has the correct head and intake gaskets, head bolts with special washers, and stainless intake bolts. The part number is TEK-1003-1206, or for those that favor the MLS multi layer style head gaskets, part number TEK-5219-1206, or any TEK kit that has the 1206 part number in it. The first number is the type of head gaskets, and we offer around 5 different head gaskets that will work with the NKB heads. The 1206 is the intake gasket part number, and that is mandatory for use with the sbc NKB heads.
Very Important Note.
If you are using an Edelbrock Performer EPS intake then you will need to use a 1205 intake gasket instead of the 1206. This is due to intake flange not covering the top of the 1206 intake gasket properly. The 1205 is slightly small for the NKB heads, and may need a very slight amount of trimming to avoid any gasket materiel hanging over into the intake runner. We have been through this procedure in our engine room many times for engines using the Performer EPS intake.
As mentioned, below is just an excerpt from several of our engine adds using the NKB heads. We also built and dynoed a 350 engine recently with the new NKB-200 heads for a customer, and will have the actual dyno results in this ad soon. The cams mentioned below are all hyd. roller cams. If you're using a lower lift than those listed below, then it would be fair to say the hp will drop, but not by much, providing your lift and duration are somewhat close to any of the cams mentioned below. This will give you an idea of what kind of power to expect with these heads, and it can certainly help you choose a cam and intake.
Please do understand that a cam is not included with the heads. This is just a guide to show what you may expect with a given combination when building an engine using the NKB heads.
PART # 180345-10 This is a hyd. roller cam for use with OE roller blocks.
PART # 110345-10 This is a retro hyd. roller cam for use with non roller blocks.
Valve lift with 1.5 Rockers: Intake .565/Exhaust .580
Duration @.050": Intake .245/Exhaust .253
Below are our dyno results on one of our engines with a set of our NKB heads using this cam and a single plane intake. The horse power numbers will usually improve anywhere from 5-10 more than what the dyno results show after the rings have fully seated.
Official Dyno report on our 406 engine with this cam, flat top pistons, and a single plane intake.
Official Dyno report on our 383 engine with this cam and a single plane intake.
Cam choice # 1 and a single plane intake.
PART # 180265-10 This is a hyd. roller cam for use in OE roller blocks.
PART # 110265-10 This is a retro hyd. roller cam for use in non-roller blocks.
Valve lift with 1.5 Rockers: Intake .530/Exhaust .545
Duration @.050": Intake .233/Exhaust .241
Official Dyno report on our 406 and 383 engines with the cam mentioned above. The 406 engine had a dual plane intake, yet still achieved over 500 hp with the NKB heads.
Cam choice #2 and a dual plane intake.
This cam and a single plane intake.
PART # 180245-10 This is a roller cam for use in OE roller blocks.
PART # 110245-10 This is a retro style roller cam for use in non-roller blocks.
Valve lift with 1.5 Rockers: Intake .500/Exhaust .510
Duration @.050": Intake .225/Exhaust .231
Official Dyno report on our 383 engine with our NKB heads and a single plane intake. Considering the low lift and duration of this cam, the hp numbers are excellent.
This cam and a single plane intake.
Check out the results on the dyno reports below using the NKB heads with one of our new Comp custom ground street rod cams. All of our engines now use the Comp custom ground cams. This cam has a somewhat low lift and duration, and produced amazing hp and torque numbers when using the NKB heads.
SBC Comp Cam OE HYD. ROLLER 520/540 Lift 236/242 Duration
110 Lobe Sep.
This cam has a step nose for use in oe roller blocks.
Reduced base circle cam. (1.050)
See dyno results below.
Special Grind # 33161
PART NUMBER: 08-000-8-11323
110 lobe sep.
Listed below is our 2.0 383 pump gas engine making 508 horse power at 5900 rpm. You would be hard pressed to find a cam of this lift and duration to produce these hp and torque numbers in a 383. We find this size cam to be the perfect all around size to give good drivability yet make outstanding performance numbers. Very little strain on the valve train components with a cam of this size. This engine had our low cost NKB heads on it, and the regular Speedmaster single plane intake.
The 421 listed below made 526 horse power with this cam and had a set of our low cost 200cc NKB heads on it with the 1.5 rockers. Very impressive considering the low cost heads, and size of this cam. Notice the torque numbers in produced. A fairly flat line from 4100 up to 5500 rpm.
Listed below are a few important solutions to preventing valve train issues while having maximum performance and longevity in your engine when running medium to large lift cams.
Head bolt washer recommendation.
Guide plate recommendation.
Stud Girdle recommendation.
NKB-200 64CC 200CC RUNNER SIZE STRAIGHT WITH STEAM HOLES PLUG FOR SBC CHEVY ENGINES
Intake Valve Dia: 2.02"
Intake Port volume: 200cc
Intake Port Dim: 2.2" x 1.2"
Int Port Location: Stock
Intake Gasket: Felpro# 1206 fits perfectly with most intakes. Should your intake drop too low, then the 1266 gasket will correct this problem. Our line of intakes have worked very well with the Felpro 1206 intake gaskets.
Exh Valve Dia.: 1.600"
Exh Port volume: 70cc
Exhaust Port Dim: 1.356" x 1.420" w
Exh Port Location: Stock location & bolt pattern
Exhaust Gasket: Depends on what type exhaust your using. Best to try and match up the gasket to your header or manifold
Flow, Intake: See chart above.
Flow, Exhaust: See chart above.
Head Bolts: Must use extended reach with true head bolt washers or head studs. See our other listings for accessories.
Head Studs: PC-2451-STUDS (12pt)
Manifold: MOST ANY
Milling: Min. Down to 58.5cc or 64.5 = .060" See info in this listing for details on this.
Pistons: Most 23°aftermarket pistons.
Push Rod length: 7.9" (also known as +100) if setup as a hyd. flat tappet. if setup as a hyd. roller 7.2 pushrods. Check this!
Push rod Guide Plate: We strongly recommend Dart flat guide plates. See our other listings for many accessories.
Retainers: Steel 10° Comp brand machined locks are used on all of our heads.
Spark Plug: Straight, .750" reach, gasket, Autolite 3923 or NGK 4554 for one step lower heat range than the Autol.
Spring Pockets: 1.550" OD (.030" deeper max)
Springs: Our Assembly: 1.46 outer diameter. single with a damper for hyd. flat tappet cams. Dual spring for hyd. roller cams.
Valve Length: 5.015" (+.100") for hyd. flat tappet cams or + .200 for hyd. roller cams
Valve Stem Dia: .3415" - 11/32"
Valve Train: STD SBC 3/8" or 7/16" stud mount
Valve Guides: 1/2" OD Int = Mag-bronze Exh = Phos-bronze (.002" press)
Valve Guide length: 1.950"
Valve Guide clearance: .0014" - .002" (with our .3415 dia. valve stem)
Valve Guide Spacing: 1.890" moved .030" from stock
Valve Seats: Hardened Ductile Iron, .006" press
Valve Seat dim. Standard
Valve Seat angles: Int = 32° - 45° - 60° - 70° Exh = 37° - 45° - radius
Stud Girdle: Use any standard girdle
Torque: Head Bolts = 65 ft/lb
Rocker Studs = 55 ft/lb
Manifold = 35 ft/lb
Block Use: Any SBC Iron or Aluminum
Weight: 59-61 lbs fully assembled pair.
IMPORTANT NOTE CONCERNING ROCKER ARM STUDS.
Stud Girdle recommendation.
I'm sure many of you have noticed there are 2 high performance engine builders in Kingsport, TN with similar names, leading to a great amount of confusion.
We are Skip White Performance, NOT White Performance and Machine.
Due to the name similarity, many customers looking for us online inadvertently find them, thinking we are the same company. Definitely not...there is no connection between the two companies. We don't have a problem with free enterprise (competition). However, when the competition builds their foundation on such things as a name similarity and their supposedly long history of being in business, then we think it's about time we set the record straight.
We have owned White Performance since 2003, with the exception of the machine shop, which was owned by Fred White at the time. He continued to operate the machine shop and build engines for us while we continued selling online under the user ID of skipwhite and the store name of whiteperformance1.
Due to their limited production capability and many disagreements about the engine and head building process as well as workmanship, we opted to open a full scale machine shop of our own a few years later. Fred White began competing against us even though our contract had a non-compete clause in it.
As our business grew, we opened a second, much larger warehouse and machine shop around 2011, located on Brookside Ln. in Kingsport TN. By putting heart and soul in this company, we have become the number one street rod engine builder in the nation.
Fred sold his shop to an investor in 2016 and the new owners continue to reap the benefits from this confusion between the two shops. This investor lacked any knowledge of this industry. They continue to use the White Performance & Machine name. Contrary to what is posted on their website, Fred White is no longer associated with the company in any way. Their main spiel in advertising is, "In business since 1979," when in fact, we purchased the White Performance company in 2003, with the exception of the machine shop.
All in all, we have been in this business going on 17+ years. Skip White's passion has been owning and building street rods for 47 years on a personal level. The knowledge he has gained over time has allowed him to venture into this business and succeed to a very high level.
The great pretenders continue capitalizing on our success due to the name similarity, but have been degrading our reputation. We have been getting calls nearly on a daily basis from people that now realize there are two shops in this town with very similar names. Customers complain of serious problems in getting their orders in a timely manner from them. They think they purchased their cylinder heads from us. Due to the confusion, there is an increasing amount of negative feedback that is affecting our name within the street rod community, when in fact we have a near perfect reputation in this industry. We have an "A+" rating with the Better Business Bureau and we have maintained the A+ rating for many years.
FAST FORWARD TO PRESENT DAY...We have become the largest street rod engine builder in the nation. Our engines, rotating assemblies, and cylinder heads are built to very high standards and shipped to our customers in a timely manner. We are a premier seller on with a positive feedback score of well over 206,000 and growing, as compared to our competitor’s score of approximately 24,000.
Our engines are custom-built to our customers' specifications and are shipped in approx. 2-5 weeks, perhaps sooner, depending on the season. Our rotating assemblies usually ship out in about one week or less, and our heads ship in about a week or less.
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