Setting Valve Lash

(The easy way)

I get many inquiries about setting lash and many times it seems this method confuses people needlessly. There are other methods, but this one has advantages:

1.1. No need to memorize firing orders ( you don’t even need to know what engine you are working on)
2.2. On most engines, doing one side at a time, you need to turn the engine very little to get to the next valve needing set.
3.3. Quicker than most methods.


Most other methods require you know the firing order, carry a little card to tell you “ find your glasses so you can read this card, put the exhaust valve on #1 on base, wiggle your nose, set #8 intake and # 2 Exhaust, turn the engine 37 degrees”, etc. Most require having both covers off and bouncing from side to side on the car, This is a waste of time , can allow the engine to cool off too much if you are not experienced, allows more chance of dirt in the open engine etc…

I suggest reading this in its entirety before starting.

REFER TO THE BELOW DIAGRAM WHILE READING THIS


The key to understanding this method and remembering it properly is understanding the above diagram. In any 4 cycle engine, the order of events is intake, compression, power, exhaust. This repeats over, so by writing out 2 cycles it becomes obvious that the exhaust valve will open before the intake. Also note that before the exhaust closes completely, the intake begins to open, creating a period of time in which both valves are open. Following that period, the intake opens and closes and then there is a period where both valves are closed. The bigger the cam, the shorter the last period becomes.

On to the method * the following is for solid lifter (flat or roller) cams:

1. Take the valve cover off the driver side after warming the engine up. (Most lash settings are hot measurements-if you adjust them too cold the lash will be too loose)
2. Roll the engine over until #1 Exhaust just starts to open- this insures you are on the front side of the lobe, NOT the overlap side, thereby insuring the intake is not open. At this point, you will adjust the intake lash on that cylinder.

3. Once you have adjusted the intake lash turn the engine until the exhaust opens all the way and closes, and the intake opens and is very nearly closed again. This insures you are on the back side of the intake lobe and the exhaust must be fully closed. The reason for stopping just shy of the intake fully closing is to make sure you don’t go too far and pass thru the both valves closed area and start back opening the exhaust. Adjust the Exhaust valve now.

4. Proceed to the next cylinder and repeat the process until that side is done. On many engines, Mopar and Chevy for example, you will notice you have to do very little turning with the exception of one cylinder on the passenger side- this saves much time and effort.

5. Once the driver’s side is done, proceed to the passenger side while your help reinstalls the driver’s side valve cover they cleaned while you were adjusting the valves…..If you are new at this you will likely need to restart and warm the engine between the driver and pass side adjustments- this is another reason to use this method rather than having both covers off.

To recap, on each cylinder, roll the engine until the exhaust just starts to open and adjust that cylinders intake. Then roll thru the exhaust completely opening and closing, the intake opening and just before it is closed, adjust the exhaust on that cylinder. Repeat until all cylinders are done.


Taken from Diamondback Racing engines Website

exhaust starts to open do the intake. intake starts to close do the exaust. easy fast. been doing it that way for manly years.

EOIC is quicker than any other method when you follow the firing order.

The 180º method:

Number 1 piston at Top Dead Center (TDC) on compression stroke.
Adjust intake valve on #2 and #7;exhaust valves #4 and #8.

Rotate crankshaft 180 degrees clockwise and adjust intake valve on #1 and #8;
exhaust valves #3 and #6.

Rotate crankshaft 180 degrees again (TDC) and adjust intake valves #3 and #4;
exhaust valves #5 and #7.

Rotate crankshaft again 180 degrees and adjust intake valves #5 and #6;
exhaust valves #1 and #2.

cold ----

i have the Mopar chart on the wall in front of the car.

Never had a problem .

Tried the other method --same result.

Jebus, it's not that hard. I just put the decal on the firewall, problem solved.

The MP chart doesn't work well for the CompCams solid roller XR274 in my 496 stroker.
When setting lash, I've found after turning the crank 90° for the next valves, the previous valves have more lash then I adjusted them with. So I was def. not on the base of the cam with that chart.
It sometimes seems the valve numbers on the chart have shifted one row.

I have used both ways but with my roller I noticed the lash wasn't the same if I checked it right after with the other method. Loose if I set them with the MP chart and checked them with the IOEC. Tight if I reversed methods. It wasn't enough to hurt any thing, but I now use the IOEC method as I figure the MP method could not have been on the base circle. Beep

I've been using the Direct Connection decal for over 20 years. I turn the engine over by hand and set 2 valves every 90deg cold. When ever I get a different grind I visually check the cam and lifter with intake/valley cover off using the decal and on my roller cams it has been right on the center of the base circle every time.