Thread: 69 460 valve train upgrade?

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Originally Posted by topgun

...I have...a 460 that I am building for my car. 1968 Lincoln Continental, original 460 motor with rail type rockers. Now, I have installed a fresh 460 of the same year and I would like to do away with the rail type rockers. I had my head redone wityh larger cobra jet valves and would like to know if I can just bolt on a set of roller rockers by just replacing the studs and installing guide plates and hardened pushrods without further modifying the heads. If so what length push rods and can I really use B>B> chevy rockers. Any help will be appreciated

In most cases, the upgrade requires only what you have noted:

• 7/16 roller rocker studs will screw directly into your 1968 year model C8VE heads. Get 1.900" effective length for your speciific application.
• Guideplates that are secured to the heads by the rocker studs, 5/16" or 3/8" pushrod applicable.
• Roller rockers, preferably for a 429/460 but most BBC-applicable rockers may be used in a build such as yours.
• hardened pushrods, 5/16 ir 3/8" to match the guidlepates.
• (stud girdles are not needed for this mild application.)

Between most aftermarket roller rocker manufacturers there is no standard in rocker arm design; therefore, you cannot know what length pushrod is needed until you evaluate rocker arm geometry via experimentation with an adjustable length pushrod. If you are not familiar with this then I recommend that you, 1) read up on it, and, 2) enlist the help of somebody that is well versed in this process.

Paul

Originally Posted by topgun

The real reason I am looking at roller rockers is that with the new larger size valves I did not realize that the valve tip on the intake valve is shorter than the exhaust and causes a clearance problem with the rail type rockers which the manual states require atleast a 1/16 gap between the rocker and spring assy. The exhaust valves rocker to spring assy clearance is fine as it should be because everything is new including the rockers. So that is wht I am leaning towards the rooler rockers for a remedy unless the is another way to fix my clearance problem.....................Rich

The different lengths on the OEM valves tips (between intake and exhaust) is the same as what you are seeing with the aftermarket valves. If you still have have the 0.0625" clearance between the rocker rails and the valve spring retainer then you are fine.

This spec exists because as the tip of the rail rocker wears, the rails get closer and closer to the valve spring retainer and may deperss the retainer and release the valve locks from position. If your rockers are not worn and you have plenty of clearance (between rails and retainer), then you are fine. That being said, a roller rocker valve train with optimized valve train geometry is still the better way to go.

Paul

Originally Posted by topgun

The valve springs are the stock ones but are all new.

Stock installed height of the OEMvalve springs is supposed to be 1.820", and the seat pressure is a measely 80 pounds or so. Hopefully you increased seat pressure slightly; otherwise do not expect this engine to rev much past 5000 rpm.

Since your installed height has not been increased, be sure to watch closely for the rocker body bottoming out on the stud even after you have determined correct pushrod length. There are a few ways around this if you have this problem.

Paul

Some thing that no one has mentioned on a 1969 head you need to machine .230 '" from the top of the stud boss. Before you install the stud and guide plate or the bottom of the new rocker will hit the integral nut on the stud . one other thing It is better to use a Boss 302 -351-429 SCJ 7/16"stud than a chevy . The chevy stud is to short and don't have enough thread holding the rocker .

Originally Posted by 417strokers

Some thing that no one has mentioned on a 1969 head you need to machine .230 '" from the top of the stud boss. Before you install the stud and guide plate or the bottom of the new rocker will hit the integral nut on the stud . one other thing It is better to use a Boss 302 -351-429 SCJ 7/16"stud than a chevy . The chevy stud is to short and don't have enough thread holding the rocker .

Machining 0.230" from the early-style heads will practically ruin them forever, and would certainly negate the longer studs you recommended. The Ford blueprint for machining down 0.230" off the stud bosses of 460 heads is for the late-style D3VE heads that have the pedestal-type rocker arms. You do NOT need to do this with the 1968-1969-1970 heads. We have built a lot of engines with C8VE, C9VE, & D0VE heads and never had to machine the stud bosses. Some people may cut them down 0.100" to compensate for the addition of the guideplates, but depending on components used and overall valve train setup this is not mandatory and can most often be avoided.

By the way, the BBC stud is 1.75"; as noted I posted in an earlier thread, use a 1.900" effective length rocker stud for the roller rocker valve train upgrade.

Paul

It has been in the ford muscle parts manual since 1969 to machine .230" off all 1968 - 72 except CJ and .300' off all 1973 -95 heads I have been building big block fords since they were introduced and have never ruined a head yet . I have had problems with heads that some one never bothered to machine the bosses down . If you look in the back of the ford racing parts cataloge you will see that the specs are still there .

417strokers,

Below is the print you are talking about; I post this all over the internet; I usually post this for machining of the D3VE pedestals for the 7/16" rocker stud conversion.

If you want to mill a whopping 0.230" off a perfectly good pair of D0VE heads when it is completely unneccesary, then I suppose I can't stop you. I certianly don't believe in such practice. Just remember that material removal of this kind is much easier than putting it back on....and/or you can always take off more later if necessary. But, we've never had to do it.

Just because someone--even Ford--tells you that this is the way that you have to do things does not mean that it's the only way to get things done, nor does it mean that it's the best way, etc. All custom builds are different and respond accordingly.

Good luck,

Paul