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right now, I've got number one piston at TOC, and I went ahead and tightened each rocker down nice and snuggly, now is this the correct method of tigthening???

if not, then how do I do it??

thanks

Jim
 

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TOC ???

Well......I've followed the method out of the Chiltons book , with good resuilts:) As far as having the engine @ TDC and adjusting all the valves.....Read the book , Thats not right. Remember that the book is telling you how to adjust with the lifters bled down...
I've also adjusted them like a xhevy....Starting @ TDC #1 cylinder and either bar'en the motor and adjusting by firing order or TDC then 180 then turn the motor 270 deg...Either way tighten the
rocker arm bolt down till you "feel" the push rod start to drag and then tighten the bolt down...should'nt turn more then 1/2-3/4 to
tighten...Factory spec is 20 ft on the bolt...Hope this helps...:)
 

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Here is how I set my rockers and I have QUIET 1.7's.

Put the number 1 cylinder on top.

Adjust intake valves 1, 4 & 8
Adjust exhaust valves 1, 3 & 7

I do them in that order BTW. Then turn the crank 180*(half turn) clockwise.

Adjust intake valves 3 & 7
Adjust exhaust valves 2 & 6

Then turn the crank 90*(1/4 turn) clockwise

Adjust intake valves 2, 5 & 6
Adjust exhaust valves 4, 5 & 8

Its easy to mark the crank and turn it the required amount.

To adjust the valves I set them to zero lash(tighen rocker bolt just enough so that the push rods wont spin freely between your index finger an thumb). I then set the torque wrench to spec and tighten them down. You need to reach the required torque spec within so much of a turn of the wrench. The 1.7s need to reach spec between 1/2 and 1 full turn, not sure about 1.6's. If you find that you do not reach the torque spec before one full turn of the wrench, add a shim and try it again. It takes a little time but it important to do it right.

I have done mine so many times I could do it in my sleep.

* KEEP IN MIND THE EXHAUST VALES ARE ON OPPOSITE SIDES WHEN YOU GO FROM ONE SIDE OF THE MOTOR TO THE OTHER. When standing in front of the car facing the motor the exhaust valve is the second valve(of each pair), farthest from you, on the passenger side. On the drivers side it is the 1st valve of each pair(closest to you).
 

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You really should check the preload (or adjust) the rockers as discussed because you have an aftermarket camshaft. It is always a good idea to check anyway. As mentioned you may need shims. Also as mentioned you want somewhere around 1/2 turn of preload. Personally I like mine to have no more than 3/4 turn. With the shims it is no problem to have between 1/4 and 3/4. I really don't want a valve hanging open.

That said, you can properly orient the engine this way: You only need to get each lifter on the base circle of the cam, completely off the ramps. Think about this ... when the exhaust valve is starting to open, the intake valve is on the base circle. When the intake valve starts to close, the exhaust valve is on the base circle. You can watch one head and set all the exhaust, then the intakes (or vice versa). Go to the other side and do the same thing. You will end up doing more rotation of the engine than with the other method described, but this method works on a 302 pattern camshaft, and on my 351 pattern cam. You can even use it on your grandmothers Pontiac and you don't need a manual.
 

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chrome302jr said:


Thats all you need to know, you dont have to adjust them, unlike stud mounts.

Ronnie

Well thats not totally true, If you dont reach your 20 ft/lbs withen a 1/4-3/4 of a turn after zero lash then you either have to get a longer push rod (less than 1/4 turn) or shim the rocker (more than 3/4 turn)
 

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Adjusting the valve train,choo-choo,chug,ah,choo,choo..

Well,The only reason I adjust them in "Order" (Any order I chose)
is to make it easy to remember which cylinder to adjust next...
And when adjusting using the picture in the chiltons book...Its not 90deg..They show it WRONG in the picture,its 270 degrees from 180 degrees, And thats for H-O & 351 order...Its important "check" lifter pre-load when you go with an after market cam Because it may have a smaller base circle...You may/ or may-not need to shim the rocker arm...:)
 

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Well thats not totally true, If you dont reach your 20 ft/lbs withen a 1/4-3/4 of a turn after zero lash then you either have to get a longer push rod (less than 1/4 turn) or shim the rocker (more than 3/4 turn)
My bad, I didnt realize he had the cam, I was thinkin stock cam. :joy:

Ronnie
 

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Turn the engine over by hand in the direction of rotation until the EXHAUST pushrod just begins to move upward to open the valve. You are now ready to adjust the INTAKE rocker of the same cylinder.

Tighten the nut on the intake rocker arm while spinning the pushrod with your finger tips. you will feel a slight resistance in the push rod when you have taken up all of the clearance. This is referred to as "zero lash." From this point it should take no less than a 1/4 of turn and no more than 3/4s of a turn to reach torque spec.

Turn the engine in it's direction of running rotation until the INTAKE push rod comes all the way up and goes back down almost near the bottom. Now set the EXHAUST rocker to "zero lash". check for the 1/4-3/4 turns to reach your torque value. Now you have set the pre-load of one cylinder. Repeat these same steps to set the pre-load on each cylinder.

If you reach torque spec after 3/4 turns you adjust with shims. If you reach spec before 1/4 of a turn you have to shave some material off the bottom of the pedestal.

This may not be the best way, but it's better than the "CHILTON WAY" because you find the cam base for each rocker separately.
 

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Dennis said:
Think about this ... when the exhaust valve is starting to open, the intake valve is on the base circle. When the intake valve starts to close, the exhaust valve is on the base circle.
Dude that's incorrect. That info about "When the intake valve starts to close, the exhaust valve is on the base circle. " comes from a typo on an instuction sheet from compcams. and from a "how to degree your cam" video put out by comp cams.

When the intake is almost all the way closed the exhaust is on the base lobe of the cam.
 

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grn92conv said:
Dude that's incorrect. That info about "When the intake valve starts to close, the exhaust valve is on the base circle. " comes from a typo on an instuction sheet from compcams. and from a "how to degree your cam" video put out by comp cams.

When the intake is almost all the way closed the exhaust is on the base lobe of the cam.
Well, actually that info is from years ago when I was at one of our local racing engine builders. You must have a really huge camshaft with serious overlap, because my intake centerline is at 108 ATDC, and it hangs open for a good number of degrees. My exhaust valve is at .006 from closed at 25 ATDC. Even if I stopped exactly on the nose of the intake lobe I don't think it is going to take 83 degrees to close that last .006.

That said, waiting for the intake is almost all the way closed as you suggest will work fine too.
 

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I did mine the Chilton way and the seems to run well. No noise either.
 

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Dennis

The way I know this is from dealing with comp cams on 2 sets of different instuctions I got from them. One set of instuctions said to adjust when the valve starts to close the other said adjust when the valve is almost all the way closed. The comp tech said that one set was a typo that also found it's way on their video. The tech also told me they have since changed their instuctions to fix the confusion.

Here's instructions from crane cams, but comp has also changed their instuctions.
http://64.90.9.168/cranecams/pdf/425e.pdf
 

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grn92conv -

Your way is fine, and truth be said my way is basically the same thing. I really don't care what part of the closing part of the ramp I'm on when I adjust. If you go through my numbers (and the ones on your cam card) you'll see what I'm saying. I challenge you to find any camshaft that has the exhaust still open when the intake is starting to close. Any of the descriptions in this post are fine. You just have to be careful using the Chilton's (and Ford) method using the specific rotate and torque sequence because you may not have the original firing order camshaft in your engine. For example I have a 351 order cam in my 302 and a buddy has a 302 order cam in his 351.

I've talked to the guys at Comp before and found it difficult to get a meaningful answer to specific questions about their products. This is true with lots of companies so you always have to sort out the bs from the truth. Heck, the guy at MSD even gave me the wrong part number for my dist gear. He was confused with a 5.0 engine running a carb and non-stock style ignigition wiring I guess.
 
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