GM Valve Train


We are an authorized and listed repair facility for Air Flow Research, AFR.

Many stock GM valve train parts are limited to 6,000 RPM.  The stock AFR is limited to 6,600 RPM.   Stock AFR springs have a lift limit of .600 and the stock GM springs have a lift limit of .570.  Our standard spring kit has .650 lift and has a wide range of application by design.  This product line goal was to bring the finest Gen III products to the end user. A major concern with any combination of valve train parts is fitment between the valve stem, lock and retainer.All of our upgrade parts are made in the USA and fit correctly.

1. Poor fitment produces spring side to side movement or excitement which results in increased spring harmonics.

2. Poor fitment will swedge the retainer out or cause pull through.

3. Poor fitment can actually snap the end of the valve stem off due to the fact that the valve stem area exhibit’s the smallest cross section in make-up.

Titanium Valve Program

RLD Performance is now selling our own 2.200 Titanium replacement valve for the LS7 and L92 cylinder heads.  It is equivalent in shape and length to the stock factory valve.  These valves may also be utilized in aftermarket heads but you should check with the manufacturer for application.  This exceptional racing valve is CrN coated to resist wear and weighs only 72 grams.  By comparison, the much smaller Manley 2.160 L92 valve weighs 114 grams.  The quickest way to valve float, decreased power and ultimate valve train failure is to install larger valves with increased weight for racing applications.  

Valve Springs

The dual spring line was designed with the finest super clean chrome silicone wire available and is further processed with shot-peening, electro-polishing and stress relieve to ensure the best possible endurance as well as performance for street or racing applications.  As you know, camshaft profiles can vary from mild to very aggressive with the same lift.  It is the customers responsibility to check and make sure that these spring pressures are correct for his cam and application.

These springs fit in the stock spring pocket with an installed height of 1.800 inches.  Prototype parts were Spintron tested to verify durability and reliability. The spring manufacturer strives to bring the best materials and quality control possible to this type of product.  After installation, break-in, temperature cycling and run time will cause spring pressures to vary. Spring pressures can vary by 2-3% out of the box.  Springs can vary significantly more by the end of their duty cycle.

The spring listed below is for hydraulic roller camshaft applications.  This spring kit has been successfully used for supercharged applications.  It is up to all customers to verify with their camshaft manufacturer the required spring pressures necessary for properly control the valve train on the seat as well as over the camshaft nose based on application.  

We are very proud to note that feedback on our LS1 upgrade spring kit under severe duty applications has been excellent.  The spring kit performed well at El Mirage on Mercedes powered Car #503 with great valve train success.  The spring kit has also been used successfully in off-road truck racing engines making approximately 680 hp by HP Engine and Dyno in El Cajon, CA.  This springs kit has also been used to solve "beehive" or conical spring valve float issues in boosted sand car applications by Danzio Performance Engineering in Lake Elsinore, CA.

Valve Spring data

P/N        Material   Dimension  # Seat  # Open   Rate/in  Coil Bind  Max lift             WT.

LS1DS     SCCS*   1.297 O.D.    130      380**    375        1.100      .650              90.6g

                              .955 I.D.  @1.800  @1.150

DS = Dual Spring. * Denotes Super Clean Chrome Silicone Wire, additional stress relieve and electro polishing  ** Spring pressures can vary by 2-3%

Note -  When using these upgrade springs, especially when upgrading to a camshaft with a much higher lift or increased rocker arm ratio, it is important to change the stock cast bodied roller lifters to a billet hydraulic roller lifter design to ensure against valve train failure.   An upgraded push rod would also be advisable for proper performance.  Consideration should be made for a rocker arm shaft system for the ultimate performance.

Titanium Retainers

It has been shown that LSX engines are sensitive to valve train weight.  Reduction of mass is critical to the stability of the engines valve train as lift increases. Titanium retainers reduce the overall mass of the valve train to ensure reliability.  However, long term durability is not as long as a good steel alloy retainer.  Ti-6,5AL-3Mo-1,5Zr-.25SI is utilized to fabricate our parts.  Mechanical properties are a higher tensile strength, higher yield strength and increased hardness over Ti-6AL-4V.  In addition, durability is significantly increased with a TCN coating applied to the spring mating surface.

The weight of our dual spring titanium retainer is only 11.7 grams.  With the stock factory light weight steel locks, our coated retainer package is the lightest, strongest and most wear resistant package on the market today.  Competing cheaper parts, some very large name companies, are not heat treated parts and are not coated.  You get what you pay for.

Valve Locks

Lock tangs are not strong enough to withstand high performance spring loads.  The lock tang should only temporarily locate the lock to the valve stem. The taper of the lock must properly mate to the taper of the retainer to form a collet effect that binds the pieces together. The more spring force that is exerted during a camshaft lobe lift cycle, the more force should be applied to keep the retainer and lock in place around the valve stem. There should always be a small gap between the two lock halves when they are installed on the valve stem. If the lock halves butt, the locks are too big for the valve stem.  Poor fitting aftermarket locks and retainers can lead to a catastrophic valve train failure.

Factory LSX 7 degree locks are adequate for long life street applications under 8,000 rpm.  RLD Titanium retainers are matched specifically to the factory locks and valve stem.

Valve Spring locators

Spring locators are also spring specific.  Locators are required on all aluminum heads. Locators are machined from alloy steel and positively prevent the valve spring from walking on the cylinder head locating point at all RPM levels. This prevents valve spring fatigue and ultimate failure.  Locators are CNC machined as opposed to a stamped part and are finished in black oxide for durability.

Oil Seals

Valve stem seals are constructed from a high quality fluoroelastomere more commonly known as “Viton”, a TM of Dupont. These seals offer the proper outside diameter for inner spring clearance. The seal body features a rigid chimney and metal clad. Seal construction offers one of the best seals available for proper oil control and service life.

Due to the vast amount of aftermarket parts for the small block Chevrolet, pricing will be on a quote basis.

 RLD Performance, P.O. Box 890066, Temecula, CA 92589 (951) 676-4948, 9am-5pm Pacific Standard Time M-F, stan@rldperformance.com