heads and cam..install questions

65notch · Aug 14, 2006

heads and cam..UPDATE>>>PLEASE HELP

i just ordered myself performer rpm heads and rpm cam/lifter kit. i would like to swap it all at once....ive build one engine before, but it was a while back. when i time the cam to the crank, i know there are divits/dashes/etc. so i can time them correct. the first question is...do i want to advace or retard this timming at all? the second question is, do i want #1 @ TDC Compression?

now for setting up the valves....i need a refressing course here too..

thanks guys

57fairlane · Aug 15, 2006

If you are not sure what you want from the cam, I would install it straight up. Measure the valve events with a wheel and even then you might have to advance or retard to get the cam on line.

Yes, number 1 should be at TDC

There are a few ways of setting valve lash on a hydraulic cam. I am assuming you have stud-mounted rockers . . .

The fastest way of doing it is to hand tighten all of the nuts down on the rocker arms. Typically as an intake valve is at full lift, the exhaust valve will be at no lift or on the base circle. Then make sure its as tight as you can get with your fingers, take (probably a 3/8) wrench and do a quarter to half a turn around on the nut. Tighten polylock as much as you can turn it (without breaking it obviously). Repeat 15 more times.

David Vizard figured out a way that is guaranteed to be on the base circle but it is more indepth and takes twice as long (probably 20 min.)
It follows the firing order, so if its an old 302 -

2 (I/E) <-> 8 (I/E)
4 (I/E) <-> 7 (I/E)
5 (I/E) <-> 3 (I/E)
1 (I/E) <-> 6 (I/E)

Bring number 1 intake to full lift and then do #6 intake. Bring #5 intake to full lift then do #3 etc . . . This pattern is the same for the exhausts.

tylerrocks · Aug 15, 2006

ditto, Install the cam at zero or straight up while #1 cylinder is at TDC of the compression stroke.

SoCalCruising · Aug 15, 2006

Did you get the roller cam or the flat tappet cam?

65notch · Aug 15, 2006

its a flat tappet

when you guys say install in straight up....i dont have a degree wheel, so how can this be accomplished without one?

65notch · Aug 15, 2006

57fairlane said:
If you are not sure what you want from the cam, I would install it straight up. Measure the valve events with a wheel and even then you might have to advance or retard to get the cam on line.

i want go fast...

iskwezm · Aug 15, 2006

65notch said:
its a flat tappet

when you guys say install in straight up....i dont have a degree wheel, so how can this be accomplished without one?

the timing set will have marks for -4*,0*,+4*. I usually set mine up +4* to get a little more bottom end.

dennis112 · Aug 16, 2006

iskwezm said:
the timing set will have marks for -4*,0*,+4*. I usually set mine up +4* to get a little more bottom end.

Be sure to verify valve to piston clearance, especially if you change the cam timing from 0* -- (voice of experience.)

Max Power · Aug 16, 2006

iskwezm said:
the timing set will have marks for -4*,0*,+4*. I usually set mine up +4* to get a little more bottom end.

It does if you buy the Edelbrock timing set. Factory sets do not have this feature.

Edelbrock tells you to install it straight up. Their manufacturing quality suggests that you really don't need a degree wheel, unless you are really anal about every last ounce of performance. Edelbrock stuff is usually extremely close to accurate.

Get the head gasket Edelbrock recomends as well as the spark plugs. If you have a 302, get the adaptors for the head bolts, and get some nice ARP head bolts. Get some thread sealer for the head bolts, and anti-sieze for others.

Turns the motor by hand with clay on a piston to make sure your valve to pistion clearance is cool.

It's pretty much a direct replacement install. You will be happy with it.

Max Power · Aug 16, 2006

Btw, for adjusting the vavlves, I always liked Crane's instructions:

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, you are at ?Zero Lash?. Turn the adjusting nut down one half to one full turn from that point. Lock the adjuster 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.

6. Both valves on this cylinder are now adjusted, and you can move on to your next cylinder and follow the same procedure again.

SoCalCruising · Aug 16, 2006

Flat tappet cam: be sure to use the recommended lube for break-in. You also want to get the engine started quickly (no prolonged cranking) - follow the Edelbrock break-in instructions concerning break-in time and RPM. If you are a little rusty with respect to installing the distributor and getting the engine timed reasonably PRIOR to start-up, have someone with you who can check your work. Again, you want the engine to fire quickly. You should also consider using an oil with proper additives for flat tappet cams - esp. during break-in. There was a thread discussing this - search for "Rotella" to find the thread. Good luck.

iskwezm · Aug 16, 2006

i can tell you that the valve clearance will be very close if you run a stock flat top piston with small/no valve reliefs. I hade the same combo and bent valves a few times.

If your going through all this work, get a new timing set, almost ALL will have marks for retarding/advancing the cam. The better ones will go in 2* increments.

65notch · Aug 16, 2006

iskwezm said:
i can tell you that the valve clearance will be very close if you run a stock flat top piston with small/no valve reliefs. I hade the same combo and bent valves a few times.
QUOTE]

the pistons do have valve reliefs...but i dont know if they are considered small or not? heres a picture

iskwezm · Aug 16, 2006

the pistons do have valve reliefs...but i dont know if they are considered small or not? heres a picture

yep,those are "stock" type. With a auto your gonna be ok, but with a stick and a over rev, you might be in trouble. I missed a couple of shifts and thats all she wrote. Also the valves are special to Edelbrock heads, so dont expect to use a universal if the need comes up. Other then that, i have no problems with them. I also did some porting and put some better hardware(springs,retainers,locks)

Tha cam will sound nasty too

SoCalCruising · Aug 16, 2006

The heads should have been bought with 1.90" intake valves (not the 2.02" valves) which should be okay with most stock 302 pistons. 1.90" is considered the largest valve that you can run with a stock-type piston.

iskwezm · Aug 16, 2006

SoCalCruising said:
The heads should have been bought with 1.90" intake valves (not the 2.02" valves) which should be okay with most stock 302 pistons. 1.90" is considered the largest valve that you can run with a stock-type piston.

they still hit. ask me how i know

SoCalCruising · Aug 16, 2006

Really? Did they hit from a too-small-diameter relief, or from a too shallow relief? And were you using late 302 pistons or early 289/302 pistons? Thanks.

iskwezm · Aug 16, 2006

SoCalCruising said:
Really? Did they hit from a too-small-diameter relief, or from a too shallow relief? And were you using late 302 pistons or early 289/302 pistons? Thanks.

I had TRW "stock" .060 289 pistons with the same looking reliefs in the pic. Like i said, it was mainly from missing a shift and revving to 6500+

65notch · Aug 16, 2006

well, ive recieved all the parts now, so hopfully everything goes kosher. the cam goes in tonite and the heads will go tomorrow...i bought some play-do today so check my clearances.

as for the overreving...i do have a manual, but ive also got a rev limited that will be well below 6500

57fairlane · Aug 17, 2006

over-rev = float the valves. Nothing to do with valve relief size.

You should, for peace of mind, measure how much P/V clearance you have.

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