SBC CHEVY 400 406 NKB-200cc ALUMINUM HEADS STEAM HOLES 64cc STR. PLUG NKB-272-SH
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NKB 200cc/64cc ULTRA HIGH FLOW CYLINDER HEADS, STRAIGHT PLUG WITH STEAM HOLES, FOR SBC CHEVY 400, 406 ENGINES.
Setup for hydraulic flat tappet cams.
200cc RUNNERS, 64cc COMBUSTION CHAMBERS.
THE BEST FLOWING, BEST QUALITY SBC ALUMINUM HEADS ON THE MARKET FOR THE MONEY.
This sale is for one fully assembled set of heads (2 heads).
The springs in these heads are set up to operate with hydraulic flat tappet cams up to .535 lift. For those running hyd. roller cams, see our other listings for these heads with the part number NKB-200-274.
The NKB aluminum heads have 64cc combustion chambers with 200cc runners, 2.02/1.60 stainless valves. These heads are not built by Procomp, and have no association with them in any way.
PART NUMBER # NKB-200-272-SH
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.
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.
These heads are also available in angle plug style, and with steam holes. See our other listings for the part number NKB-200-A-274.
A breakdown of the part number.
The NKB stands for "New Kid on the Block"; 200 represents the runner size, 272 designates the use of 100 long valves, and single springs with a damper setup for hyd. flat tappet cams. You will also see the heads listed with the number 274. The 274 designates the use of 200 long valves with dual springs with a damper, setup for hyd. roller cams. We also have the valve train setup for solid roller cams, and will have the number 583 rather than 272 or 274. The heads listed with the letter "A" in the part number are angle plug design. The letters SH at the end of the part number designate, Steam Holes. Be absolutely certain of what you need before buying. Feel free to call us if you need assistance deciding what you need for your build.
See our other listings for these heads with our Competition Series PBM valves.
These heads can be used with outer perimeter or center bolt valve covers.
Recommended accessories for these heads.
Please see our other listings.
For those running an HEI distributor, the plug gap should be approx. .040-.045 Those running an MSD 6AL unit should gap the plugs to approx. .035-.040 These values are very controversial and you may experiment as to what runs best in your engine. Widening the gap too much can put a strain on the ignition components. Be sure your plug wires are completely fastened onto the spark plugs.
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 with our 383 and 406 engines, 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. 5 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 zero 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.
The two paragraphs above were written a couple years ago. We have now sold several thousand sets of the NKB heads. To this date we have had no problems of any kind with them.
ONE YEAR WARRANTY, UNLIMITED MILEAGE.
Here is a rundown on the hardware used in these heads and the assembly process.
Melling High Performance Dual Springs.
COMP CAMS "POSITIVE STOP" VITON VALVE STEM SEALS. # 529-16
We purchase most of our valve train hardware in bulk for our engine program. Below is a copy of one of our invoices from Comp Cams showing several of our rather large purchases of valve train hardware. We have removed the price and our account number for privacy reasons. This is the best way we can prove to our customers that the valve train products we use and sell are genuine Comp Cams products.
IMPORTANT NOTE, MUST READ!
We have noticed several sellers offering these heads with a one size fits all valve springs for dual use on hydraulic flat tappet and hydraulic roller cams. We are sure this is not the proper way to setup the heads.
If they have this one size fits all setup somewhere in the middle spring pressure values of what is required for a hyd. flat tappet and a hyd roller cam, then it would be too much for the hydr. flat tappet cam, and create a wear issue. Putting too much pressure on flat tappet cams is a sure way to kill the cam. If these middle of the road springs were used on a hyd. roller cam, then the spring pressure would be too low. Valve float and its damaging effects, along with a loss of performance, are sure to occur.
We use the correct spring for your setup and it is never the same on a hyd. flat tappet as it would be on a hyd. roller cam. As mentioned above, the spring requirements between a roller cam and flat tappet cam are dramatically different. Even the odd ball solid flat tappet cam has its own unique setup depending on the lift. The one size fits all hardware claims also to work on these cams. We know of several sellers offering this insane setup to unsuspecting buyers, and it's not the proper way to set up a set of heads. We would not even consider using a spring setup like this, and believe me, the simplicity of it is appealing.
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.
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 cid engines in the 10:1 to 11.2:1 compression range. All ran on pump gas. Our Stage 2.2 383 engine ad has a selection of four different cams. I have copied this info from that ad. 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.
As mentioned, below is just an excerpt from our Stage 2.2 engine ad. 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 a 383 engine using the NKB heads.
Cam choice #1
PART # 186755-10 This is a hyd. roller cam for use with OE roller blocks only.
PART # 116755-10 This is a retro style hyd. roller cam for use with non roller blocks.
Valve lift with 1.5 Rockers: Intake .600/Exhaust .581
Duration @.050": Intake .251/Exhaust .255
Cam choice #2
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
This cam choice (2) coupled with our single plane intake and 1.6 rockers will produce right at 530 horsepower at 6,400 rpm in a pump gas 383 engine with our NKB heads. Compression ratio would be right at 10.5:1. It must be noted that the dual plane intake will have much better drivability, and throttle response is also noticeably improved. The engine would feel stronger with the dual plane intake in the bottom and mid range. The single plane intake would have a greater impact on the hp numbers if the engine were setup in race form, as we have seen up to 20hp difference on larger cubic inch engines, and/or higher compression setups with larger heads and cam.
The single plane intake is not recommended for use in vehicles weighing over 3250 lbs. Our cam timing components were left in the straight up position. Ignition timing was set at 33-34 degrees total, using 93 octane fuel. During very hot weather, total timing should be set at 31-32 degrees. This cam choice should only be used in vehicles weighing around 3,500 or less. A final gear of approx. 373 and a stall of approx. 2,800-3,200 is recommended.
Below are our dyno results on one of our 406 and 383 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.
Cam choice #3
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
This cam choice (3) is the perfect all around setup for those wanting a decent bottom and mid range, while still generating excellent power at the top in a 383 engine. This engine will use the same pistons as the cam choice above, but you could have a bit less compression ratio and that would be fine. This cam will make its peak power at approx. 5700 rpm. If your car is in the medium weight range or up to approx. 3,700 lbs, and you're wanting slightly better streetability, then this is a good cam choice. You still want to keep the final gear ratio at .323 or higher, but keeping the gear ratio on the tall side is more acceptable with this cam compared to the other choices mentioned above. You may choose 1.5 or 1.6 rockers with this cam, but we recommend the 1.5 rockers for better low end response.
This cam should be paired up with the dual plane Crosswind intake for excellent daily drivability. The single plane Hurricane can be used, but the dual plane will have much better bottom end and mid range response. You can also expect a longer valve train life with this cam compared to the larger cam choices # 1 or 2.
Below are our dyno results on one of our 383 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 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.
Cam choice #4
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
This cam choice (4) has a slightly lower lift and duration than the others offered above, and is highly recommended for use in heavy vehicles like full size sport trucks or very heavy cars. The low end response with this cam is very good. Compression ratio in a 383 could be as low as approx. 9.5:1 with this cam. Slightly higher would be recommended in a 350 build.
The rule of thumb with cam size is that the smaller the cam in a given application, the more improvement in low end response. One more benefit to the smaller cam is that the requirements for lower gearing and higher rpm stall converters is reduced. A final gear ratio of 310 would be acceptable with this cam. The bottom end power would be much better with this cam than with the other choices above. This would be the only choice for those wanting to run an overdrive transmission such as the 700R4 and cruising at around 2000 rpm in overdrive. A stall converter of 2,200 would be the minimum for this cam.
Valve train life is extended greatly with this cam as compared to the other choices listed above, drivability is at its best. Low and mid throttle response is very strong. This cam choice will also produce the greatest amount of vacuum at idle compared to those listed above.
Official Dyno report on our 383 engine with our NKB heads and a single plane intake.
This cam and a single plane intake.
THE CAMS LISTED WILL COVER MOST NEEDS FOR ANY STREET ROD.
An excerpt from our engine ad about our new dyno.
Head bolt washer recommendation.
Guide plate recommendation.
Stud Girdle recommendation.
NKB-200 64CC 200CC RUNNER SIZE STRAIGHT 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.
Head Gasket: Felpro# 17031 for steam hole applications
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 you're 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: We strongly recommend ARP # 134-3601 head bolts. Must use extended reach with head bolt washers or head studs.
Head Studs: PC-2451-Studs (12pt) or ARP brand.
Manifold: Most any. Our line of intakes fit very well on the NKB heads.
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: When running a hyd. roller cam use 7.250 length, or 7.3 if using our Comp reduced base cams. See our other listings for the best deal on premium pushrods.
Push rod Guide Plate: We strongly recommend Dart flat guide plates. See our other listings for many accessories.
Retainers/Locks: Chromoly Steel Retainers, with 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 Autolite.
Spring Pockets: 1.550" OD (.030" deeper max)
Springs: Comp 1.43 outer diameter. Dual springs with an internal damper.
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. Our Gold Series Stud Girdles work very well on these heads.
Torque: Head Bolts = 65 ft/lb
Rocker Studs = 55 ft/lb
Manifold = 30 ft/lb
Block Use: Any SBC Iron or Aluminum
Weight: 59-61 lbs fully assembled pair.
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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