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Well, when I bought my cat (almost 3 months ago - wow how time flies), I was told that when the prior owner re-built the engine, he discovered that it was a 351C H.O. - so it has solid lifters like the '71 351 BOSS engine.
Anyway, there's a bit of a ticking/pinging in the engine so it's probably time for the lifters to be adjusted.
Anyone out there have any experience with this ... I have a mechanic that I trust with my daily driver, but I'm not so sure about handing over the Pantera without any guidance.
I've found that the lash is to be set at 0.022 cold, or 0.025 hot - Anything else I should be telling him before I hand over the keys? (the nice thing is that he doesn't mind if I watch over his shoulder so I can learn a thing or two).
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You will notice with a solid lifter motor that it makes a bit more noise than a hydraulic lifter motor. Your valves may or may not be out of adjustment. As for the adjustment its pretty straight forward. Make sure the cam is on the base circle and adjust to spec. This is an excerpt from the crane cams adjustment FAQ regarding lash setting on a cold motor.
With iron block and iron heads, add .002"
With iron block and aluminum heads, subtract .006".
With both aluminum block and heads, subtract .012".
Found this info from a car craft article.
Ford (5.0 HO, 351W, 351M, 351C, 300)No. 1 cylinder at TDC compressionAdjust exhaust valve: 1, 2, 3, 4Adjust intake valve: 1, 5, 7, 8No. 6 cylinder at TDC compressionAdjust exhaust valve: 5, 6, 7, 8Adjust intake valve: 2, 3, 4, 6

Blaine
Hi Russ,

The first thing I'd do is check those lash figures! Valve lash DECREASES when hot, so you should have less when the engine is hot than when cold.

My Compcams 282S solid lifter cam calls for 0.022" cold like yours, but 0.016" hot.

Valve lash setting is tedious, at least until you get the hang of it. I'm a rookie mechanic at best but even I can adjust my valves.

BTW, hearing a ticking noise may not mean that your engine needs adjusting - it may mean that your engine is perfect! Solid lifters make a tic-tic-tic noise, not unlike a sewing machine. If the ticking is not even, then you may have a valve out of adjustment.

If you haven't adjusted them recently it is worth doing. Adjustment will change as the valves recede into the heads (I'm told not something to worry about - they won't recede enough to do serious damage for zillions of miles).

If your car sounds like a 351C-powered sewing machine, then you are good to go. It also sounds a little bit like an exhaust leak at idle. Don't be worried by it - I kind of like the mechanical noise!

Listen to blaine's advice on how to set valve lash with only three engine positions instead of bumping the motor over for each cylinder. You may want to think about wiring a remote starter button in the engine bay to help bump the engine over.

Good luck!
Ah, you asked for advice... make sure you have an extra valve cover gasket available before removing the valve covers. If it has been a while since they've been off they may fall apart when peeling the valve covers off and you may not be able to reuse.

Some people coat one side of the valve cover gaskets with vaseline to make them easily removeable and re-usable.
Guys, great advice (keep it coming).

As for where I found the 'lash' data ...

http://www.nationmaster.com/encyclopedia/Ford-Boss-351-engine

"Valve lash cold: .022 in (0.6 mm) intake and exhaust, .025 hot"

It says it on the internet, so it must be true ;-)

Anyone out there know for sure the right lash numbers for the 351C H.O.?

Thanks for the pointer Charlie, I wouldn't want to use the wrong numbers!
Actually at one time a person could vary the clearance on solid lifters in order to gain torque (looser) or rpm (tighter). At least some of the racers would.

I run a solid lifter cam in my pantera and in my Shelby as well.

It is amazing how paranoid people get when they have solid lifters. Must be from running those Chevys with solids hey? (:

You can actually make your clearances plus or minus about .002" with most solids. The more radical the lift, i.e., .650 - .700" the more important it is to be on the manufacturers specs.

I set my lifters with the engine cold, and not running. I use the Ford Shop manual which shows what Blaine is talking about.

On a cold engine I add .001" to the hot specs. Of course it is important that you know how or when clearance is established.

It is established when you can turn the pushrod with your fingers.

Then when you tighten down the lock nut on the rocker arms you tend to gain about another .001" of clearance.

I suppose that it is possible to be exactly on the clearances but the reality is that you are plus or minus .001" no matter what you do.

Oh, and if anyone wants to attempt to do them hot, good luck. You do them with the engine off. You will still get burned or at least your fingers will and you need to keep the engine hot for the three hours it is going to take.

Charlie mentioned gaskets. If you use the aluminum valve covers you don't need any. Just use silicone "form a gasket material on them". Make sure that you surround each bolt hole optherwise you will leak through the bolt holes.
Last edited by panteradoug
I set mine cold as well. Talking to other people, I've found darn few people who actually do it hot. Just isn't worth it unless you are racing for money.

I've also read what Doug says about setting the lash "loose" or "tight". I'm happy to get a reasonably consistant lash between valves!

It's important you find out what cam you have, as the lash is cam-specific...
Valve covers are the stock deTomaso covers, so no aluminum here.

As for keeping the engine hot for 3 hours, good point - cold it will be!

What Cam? To the best of my knowledge it is the stock cam ... I just found this URL:
http://www.geocities.com/motorcity/flats/3845/camchart.html
... which indicates the cam should be "D2ZZ-6250-A" with a lash of .025 - but no note on the page whether this is a cold or hot setting :-(
So, I'm wondering whether a cold lash of .023 would be a wise compromise - based on the irrefutable guidance of the internet ;-) Why, even Wikipedia says it's .022 cold (but of course it is a copy of the other article)

If it turns out to be a little high, then I can expect a touch more torque, if it's a little low, then a bit more top end power. I'm not out racing the car, just enjoying it whenever the weather and work schedule allow me to go out for a romp or to a car show, so as long as she runs strong, I'm happy.

I've found the following rule from Mad Dawg about 351C rebuilds...

Rule #1 Dan Jones is always right.
Rule #2 If in doubt refer to Rule #1

Has anyone heard from Dan lately? Even the guys on the Mustang forums venerate his words of wisdom on the 351C.

I'll also try to record the sound and post it for those with an ear for solid lifters to take a listen.
a) Dan's still around. Listen to Mad Dawg - he speaks wisely! Dan spec'd all the parts for my engine and I'm quite happy
b) I'm not sure I'm competant enough to set lash to a tolerance of 0.001" - so 0.023 may be just fine. You could perhaps search the Ford Motorsports webpage for lash, which would give the least margin for error, but if you aren't sure what cam you have then it won't help all that much either.
Hello Russ,
I just talked to crower cams tech people on cold adjustment, as long as you have an iron block and heads parts should grow together, then the clearances are the same cold. mine being intake @ .026" & exhaust @.028", it seams to be more clearance the bigger the lift as mine is a solid roller with .632" & .637". Glad you brought this up as I am in the middle of building a new engine for mine and am at the point of sizing the push rods and was going to need to check on this.

Mark
> I was told that when the prior owner re-built the engine, he discovered
> that it was a 351C H.O. - so it has solid lifters like the '71 351 Boss
> engine.

Verify this is true for yourself. Some owners will see that there
cylinder heads have been converted to Boss style adjustable valve
train (screw-in studs and guide plates) and assume they have solid
lifters. That is not necessarily the case. You can run hydraulic
lifters with an adjustable valve train. If it turns out to be a
solid lifter cam, it may not be an HO part. Without looking at
the part number on the cam, you can set up a dial indicator and
measure the lift. The HO cam should be 0.490" lift on intake and
exhaust (with zero lash). I don't have the lash handy for the HO
cam. If you can get your hands on a Ford Mustang shop manual from
'72 or '73, it should have the lash ifo in it. Also, Crane makes
exact copies of the the Boss and HO cams in their Blueprint Series
cams. If you get an HO cam card from them, it'll have the lash info.
Be aware that some manufacturers provide valve lash at the lobe so the
lash figures must be multiplied by the rocker ratio (1.73:1 for a stock
351C) to give the valve lash at the valve. You can fine tune the cam's
performance with more or less lash.

Given that you don't know for sure what the cam is or what the
lash should be, prehaps the best course of action is to set lash
0.025" cold then see how noisy it is and adjust the lash from
there until you get the sewing machine sound. You can set one
cylinder hot then let the engine cool and see what the actual
difference is hot to cold.

The valves must be set when their lifter is on the base circle of the
lobe. At this position the valve is closed and there is no lift taking
place. The SAE method (a.k.a. the EOIC method for Exhaust Open, Intake
Closed) is to:

1. Warm the engine. Once you know the difference between hot and
cold lash, you can set the lash cold.

2. Follow the firing order. You can pick any cylinder but I usually
start with number one and have a copy of the firing order and
cylinder numbering in front of me.

3. Crank the motor over by hand (socket on the balancer bolt), set
the intake lash just as the exhaust valve begins to open.

4. Watching the same cylinder, crank the engine over some more and
then set the exhaust lash just before the intake valve closes.

In more detail,

1. Remove the valve covers and pick the cylinder you are going to adjust.
If your cam is already broken in, do this with the engine fully warmed up
(takes thermal expansion into account). If installing a new cam, use the
cold specs before firing the engine, then re-lash after cam break0in with
the engine hot.

2. Hand turn the engine in its normal direction of rotation while watching
the exhaust valve on that particular cylinder. When the exhaust valve begins
to open, stop and adjust that cylinder's intake valve. When the exhaust is
just beginning to open, the intake lifter will be on the base circle of the
lobe, ready to be adjusted.

3. With a solid cam, use a feeler gauge to set the correct valve lash.
Place it between the tip of the valve stem and rocker arm. Turn the
adjust until you arrive at the proper setting then lock the adjuster in
place. In my TR8, with hydraulic lifters and adjustable pushrods, I
shortened the pushrod until I got zero pre-load (lengthended pushrod
until free play was gone), then went one turn on the adjuster. I used
a thread pitch gauge to verify my adjuster was 32 turns to the inch.
1/32 = 0.03125" or 31.25 thousands (with the Buick/Rover aluminum V8
30 thousandths cold is a good goal with a high performance hydraulic
flat tappet cam). If I'm feeling paranoid, I also used a bent wire
gauge under the lifter clip to verify the pre-load.

4. After the intake valve has been adjusted, continue to rotate the engine,
watching that same intake valve. The intake valve will go to full lift and
then begin to close. When the intake is almost closed, stop and adjust the
exhaust valve on that particular cylinder. When the intake valve almost
closed, the exhaust lifter is on the base circle of the cam. Follow the
procedure in step 3 to set the lash or pre-load.

5. Both valves on this cylinder are now adjusted, so check the firing
order and move to next cylinder and repeat the procedure.

The SAE method is more accurate than the 90 degree method described in the
Ford manual and the more overlap the cam has or the less piston-to-valve
clearance you have, the more important this method is.

Dan Jones
Thanks for all of the detail in the responses guys - and Dan for jumping in with the step by step instructions.

I'd purchased the car from Ron Reeves in Michigan, and when the engine was coming apart, he was on the phone with Gary Hall calling out part numbers and the two of them determined it was an H.O. with an XY Block - I'm anxious to get in there myself and document the parts, but I'm just as anxious to keep enjoying the car as long as possible before winter storage ... and I also don't want to end up starting something that I can't finish.

This first step of going in to work on the valve lash I think should help build my confidence - esp. since I plan on taking it to a mechanic I trust and work with him on it.

I'll post an update once it's done.
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