Please help a newbie fix his first cam install

[A67auto]

I also posted this over at the ******* forum

OK, this is the first time I have installed a cam and distro on my own and I have some issues. First let me tell you the problems.

I took out my old Comp Cam 270S solid tappet cam and put in the new Trick Flow roller cam and roller rockers. I also replaced the distributor with one that has a steel gear to match the cam.

Problems:

My car is idling rough.

When using a vacuum gauge the needle is swinging between 8'' and 12'' of vacuum at 900 RPM idle with 12 degrees of timing. The vacuum is measured at the drivers side vacuum port on the carb.

When I rev the motor, the vacuum picks up, everything is smooth and it sounds fine.

Using a timing light with the vacuum advance disconnected and the port plugged at the carb, the car wants something like 36 degrees of timing to run smooth. The timing light pick up was clamped over the #1 plug wire.


How I installed the parts:

The cam was installed “dot to dot”. The cam sprocket dot was at 6:00 and the crank sprocket dot was at 12:00.

TDC on the #1 piston was found by putting my finger over the #1 spark plug hole, waiting until it popped my finger off, putting in a maker (a thin bamboo stick) and watching it rise as I cranked the motor clockwise. I stopped when it stopped rising. The dampener show around 5 degrees.

I stuck the distributor using the EFI Initial Ignition Timing Calibration and Distributor Installation thread.

I set my intake valves by watching the exhaust valve spring start to open, then spinning the push rod and tightening the rocker nut until I felt a little resistance, then going a ¼ turn more and tightening the Allen head.

I set my exhaust valve by watching the intake valve open and waiting for it to start to close, and tightening the rocker nut until I felt a little resistance, then going a ¼ turn more and tightening the Allen head.


Trouble shooting:

I checked the order of the wires and they were OK.

Double checked TDC with the finger method.

Double checked the position of the rotor when #1 was at TDC.

Checked for vacuum leaks with starting fluid around the base of the carb.

Changed the wires so it would be 180 out and it wouldn't start and backfired.



My parts they are in a carbed 66 Mustang:

94 302 motor

Trick flow stage 1 cam using the firing order 1-3-7-2-6-5-4-8

Trick flow heads

Timing chain that has only one setting (no advance, only one dot)

Edelbrock 1405 600 CFM carb jetting set 1 stage richer rods and jets

Summit Racing Street & Strip Ready to run Billet Distributor (using a used MSD Blaster 2 coil ( was good when I took it off) and an ignition ballast resistor)

Hi-Po exhaust manifolds

Edelbrock Performer RMP intake


Any help would be appreciated.

Thanks,

Alex

 

[grainboy]

My guess would be that your valves may be adjusted too tight. I would cut the center out of an old junkyard valve cover and adjust them while the car is running. Too loose and they will clatter, but then you can get them just right, with practice. I got a valve cove at a u pull it yard for $5.

 

[A67auto]

With the car running?

 

[BubbaB1966]

You didn't say anything about changing the valve springs. You might call comp cams tech line and verify the springs you are running are ok for that cam profile. roller cams tend to need stiffer springs to keep the valves seated because if the steep lobe profile.

 

[A67auto]

The valve springs are for roller rockers.

 

[D.Hearne]

I'd say you adjusted the valves at the wrong point in time. I always adjust mine at TDC of the compression stroke for each cylinder. That way you know the lifter is on the base circle of the cam. The way you did it, it's off the base circle.

 

[gjz30075]

The valve springs are for roller rockers.

That's different than what Bubba's referring to. The springs need to be able to handle the cam profile and Comp tech should be able to tell you that.

 

[A67auto]

I called Trick Flow and they said it is ok. The heads are Trick Flow and the Cam is a Trick Flow stage 1.

 

[woodsnake]

I put an Edelbrock cam kit in my 68 with a 289. Summit sent me a set of chevy valve springs. I called them up and said, hey, these are GM springs, what gives?
Summit said, "Don't worry about it, they'll be fine..."

N O T!

You need to KNOW what the springs are, what the installed height needs to be, what the correct push rod length is, and where your PR's are sweeping the top of the valve stem.

Or, you can "hope" it all works out, and let us know when you do it all again.....

 

[10secgoal]

Sounds like it could be an intake leak. Especially if it gets better as you rev it. A valve timing issue won't really go away when you rev it. The problem just speeds up.

 

[A67auto]

Woodsnake- The springs came with the assembled heads when I bought them. How do I check the springs?

10secgoal- Besides spraying the intake with starting fluid, how else can i check for leaks?

Thanks for the help guys.

 

[68stang351]

My guess would be that your valves may be adjusted too tight. I would cut the center out of an old junkyard valve cover and adjust them while the car is running. Too loose and they will clatter, but then you can get them just right, with practice. I got a valve cove at a u pull it yard for $5.

I'd say you adjusted the valves at the wrong point in time. I always adjust mine at TDC of the compression stroke for each cylinder. That way you know the lifter is on the base circle of the cam. The way you did it, it's off the base circle.

I have made adjustments both ways and have had good luck with both. What I've been doing is to adjust them as DHearne does when I put everything together before startup.

If I have to check them at a later date I have an old stock cover with the top cut out and do it exactly like Grainboy does it.

 

[NY-67stang]

What are the cam specs.
Are you sure you just don't have a lopey cam?

That's what happened to me. I didn't know any better
I have a .5"+ lift with 1.72 rockers and a lopey idle. It pulls 5" vacuum at 700rpm but buy the time it is at cruise it is very smooth. My timing is 18 degrees (at 1000 rpm in park) and I had to put in an MSD box to get a decent idle.

Are you on the timed or manifold for you vacuum advance? You might want to try manifold.

Why are you jetted on stage rich on your carb?
What do your plugs look like?
My dyno results (351w edlecbrock 650cfm) showed I was rich at the factory setting and I'm jetted 2 stages lean and could even go leaner.