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Discussion Starter #1
This may sound crazy but I'm getting excessive rocker arm noise with the valve covers on, when they're off there is no noise. Today I adjusted the valves and with the valve covers off there was no unusual or excessive noise. It's as if the valve covers are amplifying the normal sound of the valve train. It's a 389 with '69 400 cast iron heads and stamped steel rocker arms. I bought reproduction chrome valve covers for a '65 389, they do not have baffles. Would valve covers with baffles be quieter? Could the stock rockers be contacting the valve covers? Does anyone where I can buy valve covers with baffles? I've already searched several web site. I'd like to know if anyone else has had this problem and how is was resolved. Thanks!
 

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Sounds odd. It may be as you mentioned, the rockers could be hitting the tops of the covers. If you put your hand on top of them do you feel any movement? Maybe something as simple as a double valve cover gasket may do the trick IF you need to raise the covers a tad bit. Aftermarket does not always mean factory correct and they may be an incorrect/too short of height.

Just a guess.
 

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Pull the covers off and examine both the insides of the covers, and all the "movey" parts in the heads very carefully, looking for any 'shiny spots' that don't seem to belong there. Those will be a telltale of something that's making contact.

Bear
 

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Discussion Starter #4
I did feel some movement when I put my hands on the valve covers. If a second gasket is enough to clear the valve train, I would think it should it be glued to the first gasket, correct? I will also inspect the inside of the v covers for contact marks. Thanks!
 

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I think the valve covers for old 389s were different from the covers of the 1967 and later Pontiac V8s. The old 389s had that hump on the opposite ends of the valve cover. Maybe that doesn't make any difference, but the valve covers on a 400 look different from those off a 389.

Do you still have the valve covers to the 400 heads you have on your 389? You could put them back on and see if the noise goes away or changes.

I know a lot of those reproduction parts fit like O.J.'s glove, so it won't be a surprise if your problem stems from a bad fit of the reproduction valve covers.
 

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I did feel some movement when I put my hands on the valve covers. If a second gasket is enough to clear the valve train, I would think it should it be glued to the first gasket, correct? I will also inspect the inside of the v covers for contact marks. Thanks!
Examine your rocker arms and valve retainers for shiny spots as well...

Also, previously you mentioned that you had 'adjusted the valves'. Is your valve train stock? As in factory Pontiac rockers, studs, balls, and nuts? If so, they aren't adjustable... The factory system is designed such that you torque the nuts down onto the 'bottleneck' on the stud. I forget what the exact torque spec is...

Bear
 

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Discussion Starter #7
They appear to be stock stamped steel rocker arms with screw in studs and push rod retainers. We adjusted the rockers with the engine warm and at idle, we backed off the nut until the rocker started clicking, then tightened the nut down 1/2 turn. If that is not the correct procedure, then I need to find the torque spec and proper procedure. The engine block is the original numbers matching 389, the heads are cast iron from a 69 400. The number cast on the center exhaust ports appears to be 48 but the 8 is hard to distinguish on both heads.

When I bought the car in Aug 15 it had chrome Edelbrock V covers and they are fairly tall. The after market valve covers I ordered for a '65 389, were a lower profile and at the time didn't realize the heads had been changed. They gave it the stock appearance I wanted. But now I'm going back to the Edelbrock to see if the noise goes away... I bet it will. Thanks for your input!
 

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If you have all factory style parts:



Even if you have different rocker arms --- what matters is the stud, ball, and nut... These are not adjustable, regardless of whether the studs are pressed in or screwed in. The nut is designed to seat onto the bottleneck shoulder on the stud. Torque to 20 lb.ft. Done. If they're not seated like this, they WILL back off and you'll get noise.
However, it doesn't take much modification (head milling, etc) to throw everything out of whack. So in order to make the valve train adjustable one MUST use some sort of locking nut (poly lock) such as something like these:



...that have a jam screw in the center that, when tightened down against the top of the stud, will hold them in position.

Bear
 

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Discussion Starter #9
BearGFR, I have the factory style rockers shown in the first picture with hydraulic lifters and screw in studs. Can you tell me the procedure to tighten to 20 lbs or advise me of a link for instructions? Thanks!
 

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BearGFR, I have the factory style rockers shown in the first picture with hydraulic lifters and screw in studs. Can you tell me the procedure to tighten to 20 lbs or advise me of a link for instructions? Thanks!
Note in the photo Bear provided that the screw-in rocker arm stud has a shoulder. The stud goes from a 7/16" base and then necks down to a 3/8" threaded end, thus the term "bottle neck" stud. The stronger aftermarket screw-in studs have the 7/16" base and a 7/16" threaded end providing a much stronger stud. This is one of the recommended upgrades if you are going with a better than stock cam having higher lift & heavier valve springs, faster opening rate, going to 1.65 ratio rocker arms, or using a roller cam.

With your factory set-up, you simply torque them down with a torque wrench set at 20 foot lbs. It is best to have the rocker arms on the base of the cam where there is no pressure - lifting the rocker arm up. Simply rotate the crank until the rocker arms are even/same position with no lift. Then torque.

The factory rocker arm nuts are not of the locking type and even when I have used the aftermarket supplied factory type rocker arm nut lock nuts which say they will lock down and not back off - they do after time.

The photo Bear supplied shows the rocker arm pivot ball which seats in the rocker arm. It appears to be a non-grooved smooth ball as opposed to a grooved pivot ball. I uploaded a photo that shows a grooved rocker arm ball. You can see the small grooves on the sides - the balls are not smooth. These type of Rocker Arm Pivot Balls are specially "grooved" on the lower radius to improve lubrication while reducing friction and heat with stock style, stamped steel rocker arms when employing higher spring pressures in high performance applications. In some instances, rocker arm galling/blueing can occur along with excessive high heat due to the lack of lubrication under high spring loads or high RPM's and can wear out/damage the rocker arms and cause a change in rocker arm geometry due to the worn surfaces in the rocker arm cup. Most aftermarket rocker arms typically come with the grooved balls or you can buy them as a set.

Here is what Comp Cams says about their rocker arms and use of 3/8" self-locking rocker arm nuts - Pontiac Magnum Roller Rocker Arms™ are supplied with larger, thicker rocker arm balls and 3/8" self-locking nuts. These components convert your non-adjustable valve train to permit valve lash adjustment (by using thicker rocker arm balls which don't allow the rocker nut to be torqued down on the bottle neck studs like the factory rocker nuts need to do). DO NOT TORQUE ADJUSTING NUTS PER FACTORY SPECIFICATIONS. Follow steps 7, 8, & 9 for the correct valve adjustment procedure. Personally, Ditch the 3/8" self-locking nuts described above and get the Polylocks. Then adjust your valves using the "clicking" method.

Use of high pressure or high volume oil pumps can cause galling of the pushrod and pushrod seat, and burn up the pivot ball and the rocker. If high volume or high pressure oil pumps have to be used, then you will need to purchase a set of valve train oil deflectors to put over the rockers arms, ensuring that the oil does not shoot over the top of the rockers. Pontiac used the oil drippers which bolted to the heads or the valve covers which had oil drippers spot welded to them. This catches/keeps the oil "dripping" down into the rocker arms to keep them and the rocker arm balls lubricated.

That said, you cannot adjust your valves using the valve "clicking" sound and then tighten until it stops. If you want to go that route, you have to use the Polylocks as shown at the bottom of the photo. These come in 3/8" and 7/16" versions as well as tall and short installed heights depending on your needs and valve cover clearances. Some will be too tall to use with stock valve covers and require aftermarket covers being taller.
 

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Discussion Starter #12
PontiacJim, thanks for the info. I will double check for the grooved rocker ball. As I recall my rocker balls had an oblong opening but I did not notice any grooves. We first tried the cold method shown Below but when we got to #8 intake it was out of whack. We then started the engine and let in warm up and did the clicking method and everything appeared to be good. When I put he Valve covers back on we could hear racket that seem to be coming from the valve covers. Again thanks for all the info, this was modified before I bought and it's been a year and a half since I've had it on road. It has a mid-range power cam, headers, Edelbrock intake and 750 Q-Jet. I will update you in the next couple days with what I find.

Pontiac Rocker Arm Adjustment

Whether you have decided to stay with the stock type stamped rocker arms or Competition Cams Magnum Rollers Rockers as pictured here, or something far more exotic, you will need to adjust valve lash. Torquing the adjusting nut per the old Chilton's to 20-25 ft pounds won't work on any heads that have been milled. This is especially true with the high lift cams of today. The valve train needs to be adjustable. Some form of lock nut must be used. I prefer Mr. Gasket's poly lock nuts.

In the past, I've adjusted hydraulic lifters with the engine running, backing off the nut until the rocker clattered, and then turning the nut slowly until the noise dissipated. That process sure works but is just too messy for me. No matter how hard I tried, oil got past the restrictor clips, and my fabricated valve cover oil catchers--oil went everywhere. Nobody should endure that nonsense. I 've found that adjusting valve lash can really be performed while the engine is cold. The adjustment, when done accurately will preclude further adjustment with the engine running.

An important point to remember in adjusting valve lash is that the adjustment must be performed while the lifter is sitting on the base circle of the cam lobe you will adjust. Below is the technique I use. The sequence works on all V8's with the Pontiac firing order--

Firing Order
The firing order on all Pontiac motors is 1-8-4-3-6-5-7-2. The best place to start the adjustment process is to begin with the #1 cylinder. Whether you are building a new motor, swapping in a cam, or adding other upper valve train components, start with the #1 cylinder. Silly as this may seem to some, the #1 cylinder is on the driver's side cylinder bank. The driver's side has the odd number cylinders: 1-3-5-7. The passenger side has the even numbered cylinders: 2-4-6-8. [Number's 7 and 8 are closest to the firewall. (There will be a test on this later.)]

Identify Intake and Exhaust Valves/ Springs
You can't adjust anything until you know where everything is located. This sounds really basic, but you must accurately identify each valve. If you must, use a small piece of masking tape and stick it on the head with each corresponding valve identified. For example, 1X and 1I. Believe me, doing this will save some time. Preparation makes things go smoothly. Besides, who like to do things over. You won't do the wrong valve doing it this way.

Locate TDC on #1 Cylinder
Numerous valves will be adjusted at one time in this process. You must locate top dead center (TDC) of #1 cylinder. I prefer turning the crank by hand because I know exactly where TDC is on my motor. Remove all the plugs if you haven't already done so; it makes life easier on you or your starter. Locate TDC on #1 by locating the '0' on the timing tab with the harmonic balancer line. You can determine whether it's really the #1 cylinder a couple of ways. One way is too look at the hydraulic lifters. If the hydraulic lifters are down and level you're on # 1 TDC. Another way is the old "thumb in the dike" method. Place your thumb in the number one spark plug hole while the engine is being turned by the starter. When TDC is near, your finger will be pushed out by the compression. ( I know this is basic stuff.) When that happens, align the harmonic balancer that fraction or so to get TDC. Remember, the lifters must be on the base circle of the cam lobe for the adjustment to work.

Adjustment Begins
With the engine at TDC on #1 cylinder you can properly adjust the following valves after lubricating the rocker ball, valve stem, and pushrod contact point:

INTAKE 1 2 5 7
EXHAUST 1 3 4 8
The Adjustment Procedure
Remove all of the slack out of the pushrod and rocker arm by slowly tightening the adjusting nut. You must use your sense of touch here. Lightly turn the rod with your fingers while tightening the nut. As you do so, you will begin to feel resistance. When the resistance reaches a point where it requires more grip (torque) to turn the rod, stop! At this point you have removed all of the play out of the pushrod and are at "zero lash." Now you may make the final adjustment. With wrench or socket in hand, tighten the nut 180 degrees (a 1/2 turn). If you are using poly lock nuts, tighten the set screw against the rocker arm stud after the 1/2 turn. Be sure the adjusting nut does not move. (Hold it stationary with a wrench while you use the allen wrench to tighten the set screw.) Thereafter, for added insurance, add a tad more turn to the poly lock nut...just a tad. This will set the screw tightly against the stud so it won't back off.

Do all intakes valves (1-2-5-7) first and then proceed with the exhaust valves (1-3-4-8). Since you are using "feel" take your time. Run through each valve twice, if you must, before proceeding to the next group of valves.

Locate TDC on #6 Cylinder
The next step is to rotate the engine 360 crank degrees to get the #6 piston at TDC. Use the same technique for locating TDC on #1 .

Adjustment Resumes
With the engine at TDC on #6 cylinder you can adjust the following valves after lubricating the rocker ball, valve stem, and pushrod contact point:

INTAKE 3 4 6 8
EXHAUST 2 5 6 7
Adjustment Procedure Reiterated
Remove all of the slack out of the pushrod and rocker arms by slowly tightening the adjusting nut. You must use your sense of touch here. Lightly turn the rod with your fingers while tightening the nut. As you do so, you will begin to feel resistance. When the resistance makes it difficult for you to turn the rod without more grip (torque), stop! At this point you have removed all of the play out of the pushrod. You're now at "zero lash." Now make the final adjustment. With wrench or socket in hand, tighten the nut 180 degrees (a 1/2 turn). If you are using poly lock nuts, tighten the set screw against the rocker arm stud. Be sure the adjusting nut does not move. Hold it stationary with a wrench while you use the allen wrench to tighten the set screw.

Do intake valves (3-4-6-8) first then proceed with the exhaust valves (2-5-6-7). Since you are using "feel" take your time. Run through each valve twice to be certain everything looks and "feels" right to you.

Final Step
Re-lubricate the rocker assembly before installing the valve covers. If you've taken your time to be accurate no further adjustment is necessary.
 

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The process for the factory setup is... there is no process. Remember they aren't adjustable - all the rocker nuts get tightened down onto the stud 'bottlenecks', tight enough so that they won't come loose. So I guess the process is 1) get a torque wrench 2) tighten all the nuts to 20 lb. ft. :D

All the 'processes' that have you turning the engine over to different positions, doing certain valves on certain cylinders --- don't apply here. What those procedures do is ensure that the lifter being adjusted is at its lowest point, riding on the base circle of the cam, so you can take all the slack out of the pushrod at that point. None of that matters with the factory Pontiac setup - it's not adjustable - all you're doing is getting the nuts tight enough so they won't back off. The lifter/pushrod preload will be whatever it will be at that point. If you think about it, you'll see all that matters is while the engine is running that the piston inside the lifter that is actually operating the pushrod never bottoms out in the lifter bore nor does it ever hit the retaining clip at the top of the lifter bore. As long as it's riding "somewhere in the middle" at all rpm, then everything's going to be hunky-dory.

Pontiacs are -NOT- chevys...

The only times any of those processes apply are in situations where the system has been converted to one that IS adjustable - using some sort of poly-lock rocker nut.

Bear
 

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OK, I see where you got your info. Bear is correct, and as I stated earlier, the factory Pontiac heads with the bottleneck studs are not intended to be adjustable using the factory rocker arm nuts. They are not locking nuts and need to be torqued down to prevent them from backing off. The Pontiac article is a little misleading/confusing when they state in the opening sentence,"Whether you have decided to stay with the stock type stamped rocker arms or Competition Cams Magnum Rollers Rockers as pictured here, or something far more exotic, you will need to adjust valve lash."

What they should have said first was, "Torquing the adjusting nut per the old Chilton's to 20-25 ft pounds won't work on any heads that have been milled. (EXCEPT, they did not state how much has to be milled, .020", .030", .060"???. I've had heads milled .010" to clean up the surfaces - no need to use adjust anything, just torque the rocker arm nuts per factory). The valve train needs to be adjustable. Some form of lock nut must be used. I prefer Mr. Gasket's poly lock nuts." As noted earlier, the Comp Cams Magnum Rollers explain their process and include thicker rocker arm balls along with factory type locking rocker arm nuts.

Again, you can certainly use the "clicking" method to adjust your valves AS LONG AS you use the correct and needed locking rocker arm nuts or Polylocks to do this. Otherwise, you cannot do this with your factory rocker arm nuts as they will back off IF not torqued down to 20-25 ft lbs of torque.

So if you want to be on the safe side because you are not sure about the clearances because you don't know how much the heads, if any, have been milled, then adjusting your valves by the "clicking" method is fine, but do get a set of Polylocks (or factory style locking rocker arm nuts - https://www.summitracing.com/parts/cca-1400n-16/overview/ ) so that you can do this. The Comp Cams locking nuts are cheap and will work, but I and other prefer the Polylocks which are a little more work to use, but typically hold better in my experience, than the locking nuts. However, you will not have to worry about valve cover clearance issues as you might with the Polylocks. So you might just want to order the Comp Cams locking rocker arm nuts and the grooved balls (if you don't have them already), then you will be good to go. :thumbsup:
 

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Discussion Starter #15
Ok, so if I have bottle necks studs, I simply torque the nuts to 20-25 lbs, no worries about rotating the engine to be on the base of the cam, Correct? I will double check to make certain I have bottle neck studs.

BTW, The article I copied was from Pontiac Street Performance by [email protected]. Thanks guys for you time and expertise, this is much simpler than I thought. The last vehicle I adjusted valves on was a '65 VW Beetle back in the day, and I hired a mechanic to do that! LOL!
 

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Discussion Starter #16
Well guys, I took the valve covers off again and it was very apparent the rocker arms were beating the shit out of the valve covers, pardon my French! The #8 exhaust rocker had hammered a hole through the V cover! All the other rockers, except one where the breather is, showed marks on the V covers. Now I know why the previous owner had high rise Edelbrock V covers! These are '69 400 #48 heads. I bought the original style valve covers for a '65 389. I do have the bottle neck studs 7/16 & 3/8" and ... the rocker ball has an oblong hole. With this set up I suppose torquing to 20-25 lbs is still the correct way to tighten the rockers? I will probably add poly locks in the near future. Thanks for all the advice!
 

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RM: "I bought the original style valve covers for a '65 389."

PJ: You can get valve cover spacers in a variety of heights, 3/8", 1/2", or 1" that will fit under your 389 valve covers to get them higher to clear the rockers if you still want to go with the 389 valve covers. They come in polished or natural finishes. If I used them, I might get a natural finish and paint them the same color as the block to make them blend in a little better. Here is one company that offers them, they are high priced, but there are others and prices do vary. MediceMfg ...Valve Cover Spacers - Pontiac

If you do not need much additional clearance, then the cheaper alternative would be to double up on the valve cover gaskets. Butler has thick gaskets in 5/16". Glue 2 together with some good old fashion Indian Shellac and that will give you 5/8", and tighten them down snug will probably bring it more in like 1/2". http://butlerperformance.com/c-1234816-gaskets-valve-cover-gaskets.html

RM: " I do have the bottle neck studs 7/16 & 3/8" "

PJ: Then you torque them down and let it go at that. BUT, keep reading under "My Concern.".

RM: "the rocker ball has an oblong hole."

PJ: Oblong hole? Is this where the stud goes through, or are you describing the oblong "hole" on the side of the ball - which is the oil groove? The hole in the center of the ball that fits down onto the rocker stud should be round, not oblong, if that is what you are describing. If the center hole is oblong, this may allow the rocker arm to shift around. Your rocker arm should have a nice long slotted hole so it does not go into bind. You typically want these when cam lift nears .450" and higher. I provided a photo from the net. The rocker on the left is a typical rocker arm. The rocker arm on the right is an aftermarket "long slot" rocker arm.

PJ: NOTE: MY CONCERN. Do you know if the heads have been milled or how much, if any? If the heads have been milled as I stated earlier, simply torquing the rocker arm nuts down to factory 20-25 ft lbs may not be a good thing. Milling heads, using thinner head gaskets, or even valve jobs can all alter the rocker arm geometry. Hydraulic lifters require a "preload" of .020" - .060". When the parts were factory new or if the heads were never milled, no need to worry about this. But if the heads were milled and great amount and you torque the nuts down, you may cause the plunger in the hydraulic lifter to seat too low in the body and this can lead to problems - to include holding the valves slightly open.

Fairly simple to check this. Since you will be torquing the nuts down, a different method needs to be used in making sure you have the correct preload on the lifters and you don't bottom them out IF any changes were made to the heads. You Tube has a couple of videos on setting lifter preload on non-adjustable valve trains that may be of help, and you can use a dial indicator for greater accuracy as well.

I would only check one set of rocker arms to make sure, the rest should be OK. These instructions are from Crane Cams.

Adjusting Hydraulic Lifters for Proper Preload

In order to adjust the preload the lifter must be properly located on the base circle or “Heel” of the lobe. At this position the valve is closed and there is no lift taking place. You will need to watch the movement of the valves to determine which lifter is properly positioned for adjusting.

1. Remove the valve covers, and pick a cylinder you are going to set the preload on.
2. Hand rotate the engine in its normal direction of rotation and watch the exhaust valve on that particular cylinder. When the exhaust valve begins to open, stop and adjust that cylinder’s intake rocker arm. (Why? Because when the exhaust valve is just beginning to open, the intake lifter will be on the base circle of the lobe, the correct position for adjusting the intake.)
3. Back off the intake rocker arm adjuster and remove any tension from the pushrod. Wait a minute or two for that hydraulic lifter to return to a neutral position. The spring inside the lifter will move the pushrod seat up against the retaining lock if you give it time to do so. (If you are installing brand new lifters they will be in the neutral position when they come in the box.)
4. Now spin the intake pushrod with your fingers while tightening down the rocker arm. When you feel a slight resistance to the turning of the pushrod (and you cannot move the pushrod up & down), you are at “Zero Lash”. Turn the adjusting nut down one half to one full turn from that point. Lock the adjuster (this is in reference to Polylocks) into position. The intake is now adjusted properly.
5. Continue to hand turn the engine, watching that same intake. It will go to full open and then begin to close. When it is almost closed, stop and adjust the exhaust rocker arm on that particular cylinder. (Again, when we see the intake almost closed, we are sure that exhaust lifter is on the base circle of the lobe.) Loosen the exhaust rocker arm and follow the same procedure described before in steps 3 and 4 to adjust this rocker arm.


From what I have read here on the internet, 1 full turn of a 3/8"-24 rocker arm nut will compress the lifter plunger .040". What I would do is get the lifter to "zero lash" by following step #4 above. Then I would use the torque wrench and set it to 20 ft lbs. Tighten the nut making note of how much you have to rotate the nut before it reaches the torque value of 20 ft lbs (torque wrench slips/clicks @ 20 ft lbs). If it torques down to 20 ft lbs anywhere from 1/2 to 1 full turn of the nut, then you are good. IF it takes more than 1 full turn, let's say 1 1/2 or 2 turns, then then your rocker arm geometry is off and you will need to fix this. If you can turn the nut more than 1 full turn before the nut torques down, you will need longer pushrods. If the nut were to tighten down less than 1/2 a turn, then you would need shorter pushrods.

If you find you need a longer or shorter pushrod, then this conversation goes to the next level - checking/verify your rocker arm geometry. Here is a simple way to do this should this be the next step: How to Verify Valvetrain Geometry - Lunati Power

I assume this is probably a little confusing, even for me, but I don't want to see any engine damage come from a wrong adjustment on the rocker arms not knowing exactly what has been done to the engine's heads. I am no engine building expert, but there are things I know to check when building or playing around with an engine. So take all this with a grain of salt as they say. :thumbsup:
 

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Discussion Starter #18
PJ, thanks again for info. Since the 389 valve covers are now ruined, I am going to buy a new set for the '69 400 heads. I will call the previous owner about whether or not the heads were shaved. He had the engine rebuilt in '04 with 10.75:1 compression and it has probably less than 5,000 miles since then. Recent compression check showed a range of 190-210. Last week we used the "clicking" method to take slack out of the rockers, assuming the heads have not been milled should I still torque the rocker nuts to 20-25 lbs or leave as is?

Which brings me to another question. I've read where today's 93 octane gas is not compatible with high compression engines, I've been adding octane booster and it runs fine. But I wonder how much I could lower the compression with thicker head gaskets? Any recommendations on thickness to get to a target compression ratio? Thanks, Roqetman. PS, I did not find the pic of the rocker arms you referenced above.
 

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PJ, thanks again for info. Since the 389 valve covers are now ruined, I am going to buy a new set for the '69 400 heads. I will call the previous owner about whether or not the heads were shaved. He had the engine rebuilt in '04 with 10.75:1 compression and it has probably less than 5,000 miles since then. Recent compression check showed a range of 190-210. Last week we used the "clicking" method to take slack out of the rockers, assuming the heads have not been milled should I still torque the rocker nuts to 20-25 lbs or leave as is?

Which brings me to another question. I've read where today's 93 octane gas is not compatible with high compression engines, I've been adding octane booster and it runs fine. But I wonder how much I could lower the compression with thicker head gaskets? Any recommendations on thickness to get to a target compression ratio? Thanks, Roqetman. PS, I did not find the pic of the rocker arms you referenced above.

OK, just added the pic. Left is regular, right is long slot.

You do not use thicker gaskets to lower compression.

Yes, assuming the heads have not been milled, just torque them down and you will be good to go.


Long slot rocker arm.jpg
 

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Discussion Starter #20
Thanks for the pics, I'll compare mine to the ones shown. The previous owner didn't recall if the heads had been milled. Thanks again for all your time and advice. You all have been very helpful! Roqetman
 
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