Performance 3100/3400 Cylinder Head Set

Performance 3100/3400 Cylinder Head Set


Product Information

Pricing/Options will be added soon!

New for 2018, these performance cylinder head options represent the best we have to offer for every budget, with every option and recommendation based on research and experience. Multiple stages, with options within each stage to allow you to get excatly what your goals require.  Every set of heads are cleaned, baked, blasted, and pressure tested.  Common to these aluminum heads are stress cracks, between the seats and between the intake seat and the spark plug hole.  None of these are cause for concern, as we have never seen one cause a seat to fall out, or leak coolant.   We test them to make sure each head isn't "The One" to prove us wrong.  Because of this, core returns are accepted with these cracks.  

Gasket Matching is not something we consider for our port work.  Gasket makers don't design performance heads, and opening up intake and exhaust ports for the sake of matching the gasket is a good way to hurt the efficiency of your heads.  Instead, we call our work Port Matching instead.  Each port is matched to the next as best as possible, since they are sand cast parts and have their own "flaws" which may not be useful to "correct'.  Increasing power is more important than making an aesthetically pleasing work of art for you to admire.   

Valve Jobs are listed as a brief descriptions below, but it is important to understand that a 5 angle valve job done for drag racing is not the same as a 5 angle valve job done for demolition derby.  One needs flow, the other needs the valves to seal under the worst of conditions. Because of this, 2 identical heads other than the valve job can have drastically different flow numbers, and performance levels.  If you want the best for your application, be sure to tell us what you are doing.  Making a listing to cover everything we can do is next to impossible, so we are doing the best we can to keep it simple and hope you will contact us to be certain you are getting every detail down for your application.  We offer inspection and refresh rates for racers who wish to get the best performance possible year after year.

With that said, we have broken down our work into the follow stages.  The springs are kept the same for each stage for simplicity, as the camshaft used will ultimately determine the springs, and any extra machine work necessary.  Until this listing is completed, please contact us for ordering information.

Stage 0 - $749.99

We offer this set of heads an an introduction to what we have to offer, for those that don't want to put a lot of money into their build yet want something better than stock while they have the heads off.  Ports are meant for stock intake manifolds to be used.  If you order a set of our manifolds or have our manifolds already, we can use that work as a guide for matching the ports.  Valve job utilizes our durability based seat angles and widths.  

  • Reconditioned valves
  • Porting consists of bowl blend/pocket porting and a mild deshrouding in the combustion chamber
  • 5 angle valve job on the intake, 3 angle on the exhaust.
  • Stock replacement valve spring seat/valve stem seal combination.
  • Comp Cams 26986 Springs - Great for a lot of cams, including our popular Street/Strip cam

Stage 1 - $999.99

  • 3500 Valves - Lighter and slightly improve flow over stock 3100/3400 valves
  • Port matching, bowl blend, and deshrouding of the valves
  • 5 angle valve job on intake, 3 angle on the exhaust

Stage 2 - $1319.99

  • Stainless 1.8/1.42 Valve set - 1mm Oversize Intake Valve improves flow considerably
  • Port matching, bowl blend, full deshrouding of the valves
  • 5 angle valve job on intake, 3 angle on exhaust

Stage 3 -$1559.99

  • Stainless 1.8/1.52" Valve set - 1mm Oversize Intake, 2.5mm Oversize Exhaust for the best flowing combination for boosted applications
  • New exhaust seats installed to support the larger exhaust valve.
  • Not recommended for NA applications - Larger exhaust is detrimental to performance on non boosted applications.
  • Port Matching, Bowl Blend, Full Deshroud for max flow


  • New Guides - $80
  • Bronze Guide Liners - $120
  • Machine Spring Pockets - $120
  • Manley Steel Retainers and Keepers - $120
  • Manley Titanium Retainers and Steel Keepers -$295
  • Welded Exhaust Ports - $240

New guides are an excellent idea for a couple reasons.  Wear in the guides is caused by the rocker arm geometry creating side load on the valve, which wears the top and bottom inner diameter of the guide.  This created extra movement for the valve head around the seat, and cause lower the dynamic compression of the engine as the valve doesn't seat properly and the valve stem to rocker arm contact is less stable.  The other reason to consider new guides are for the valve job.  A pilot is used in the guide to locate the seat cutter and is a much closer tolerance to the guide compared to the valve stem.  .0002" increments to be exact, so it is only going to be this tight where the guide isn't worth.  Allowing the pilot to move in the same wear pattern as the guide will allow the seat cutter to follow a path that isn't perpendicular to the guide, and concentricity is thrown off considerably.  In lamen's terms, your valve job won't be as good if the guide is worn.  We use gage pins to determine how worn the stock guides are and can tell you if there is need to be concerned.  

Bronze guide liners are another way to bring the guide back to its former glory, only with the added benefit of a self lubricating surface that also allows for a tighter clearance between the valve stem and the guide.  If you do some ressearch on this method, you are bound to run across people having negative comments regarding longevity.  There is a good reason for this.  Installing guide liners is not something you can do without precision, both on the installation, and on the valve job.  There are multiple kits out there, and there are multiple methods to size the guide.  The short story is, we use a go no-go gauge to determine if the cutter did its job properly and hasn't worth too much to create a tighter hole than allowed.  We have also made a clamping setup for the jog to align the cutter to the seat so that we can follow the existing hole and keep the geometry spot on.  Sizing the hole is a 3 step process, plus a honing process which introduces a cross hatch for oil retention.  Cutting corners on this process is where you have wear issues later on, including a polishing step for the valve stems themselves.  We do not offer guide liners for use with reconditioned valves.  

We aren't done discussing the bronze guide liner though, because it is equally important to get the valve job concentricity within spec, or broken valves are possible.  It is normal to have the valve head move on the seat, but if the valve head needs to move more than the guide to stem clearance allows, you will either have increased wear in the guide, or you will have a broken valve.  So why go through all the work to make guide liners work when new guides should be fine?  Performance.  A tighter clearance between the stem and guide will increase vacuum in the intake port and recduce oil consumption past the valve stem, and reduce blowby on the exhaust.  Durability is also improved if this is all done properly, which is why we are explaining this for so long.  The cost of doing guide liners is more than just the guide liner itself.  It is the entire process of making each component work as perfect as possible.

Machining the spring pockets is much simpler to deal with.  If you have a high lift cam, such as the XFI based Race cam or something similar, stiff springs are necessary to keep the cam happy, yet our 1.700" install height also brings coil bind into play much sooner than other engines.  Increasing the install height to 1.760" is usually enough to use the 26918 springs with the race cam and spin the engine to 7000 RPM.  If you have any questions about your cam and springs working, just contact us and we can let you know.  Most cams up to .540" lift are ok without having any extra machine work done to the heads. 

Manley retainers and keepers are a nice upgrade over stock to reduce valvetrian weight, and allow more room between the rocker and retainer.  Stock are stamped, Manley are machined.  Titanium reduces weight even more but isn't as durable as steel.  Great for drag race use.

Welded exhaust?  From experience, most people will look at the stock port and then our welded port, and say the stock port will flow better.  "You need to hog that out".  Problem is, you don't want to hog anything out.  It makes the ports less efficient.  GM actually did the leg work on this, as seen in the 3500 cylinder heads.  They filled in the dead space of the port to increase velocity, which keeps the exhaust energized to exit the engine.  This was going to become standard work on the stage 2 and 3 heads, but as an option, you can determine if you want to spend the money for more power.  If you have a turbo, this modification will equate to faster spool.

This listing is new still, and will require a lot of pictures and probably some video as well to help explain what is going on.  Dyno and track results will be posted as we get them, and flowsheets will be posted as well.  While the work done from 2004-2016 was well researched and the results well worth the investment, we think this new round of research will further prove these engines are a great source of power for the compact size of the engine and weight.  Thanks for reading!

Product Code WOT34G3HS
Manufacturer WOT-Tech
Condition New
Weight 30Lb