Engine Problem
 

1965 Pony "A" block with T-10

Just had the heads done and installed a new cam.
Valve lift .450/.474
SAE dur. 280/289
SAE timing:btc 27/abc 73/bbc 75/atc 34
Initial timing is 10
Went finger tight on pushrod plus one turn.
The car runs okay but performance is worse than stock.
Also, the car sounds constipated at the tail pipes.

What did I do wrong? What should I check?

Re: Engine Problem
 

What kind of ignition do you have? Stock? Electronic?

How did you time your distributor?

What is initial advance?

What is total advance with vaccuum disconnected and plugged?(read at 3000 rpm and you may need a protractor to mark your harmonic before starting the engine - you'll want marks at 24 degrees advance and 34 degrees advance - white chalk marks will do fine just make sure to mark them carefully). Expect to get a reading of about 24 degrees for this step.

What is total advance with vaccuum advance connected? (read at 3000 rpm and you may need the protractor...). Expect to get a reading of 34 degrees.

What is your ignition timing and are you reasonably sure the cam was timed right? Who did the installation?

I know this sounds like a lot of questions but without knowing the results of the above, its hard to help you diagnose your problem. Sounds like its running very retarded amd that either the cam gear and crank gear are off timing, or the distributor is off timing or lastly, the timing chain has jumped.

You should also check to make sure your Distributor is lined up pointing to the first spark plug when you are at top dead center. Your car will run if it is not but like crap. Also check to make sure your spark plug wires are going in the right order.

One

Oh one more thing too. Make sure you have the PCV valve going from the valve cover to the plate on the bottom of your carb. I forgot to do that when I built my first motor and I couldn't figure out why my car seemed like it was working so hard to not go every fast. Also make sure you have a breather cap on the other valve cover.

One

A full turn on the rocker arm studs adjustment nut after finger tight sounds a little too much to me. I use about 1/2 turn after finger tight. Too much there will not let your valves seat completely. I'm not sure that is what's wrong , but it could be. BTW, we're talking about a hydraulic lifter cam as apposed to a solid lifter cam aren't we?

Rev

I would say it could be inproperly adjusted valves also. Are they roller rockers or stock rocker arms. Also, until recently, I thought you should have a breather on one side of the motor also. But it was pointed out to me, that in a mildly beefed up or stock motor, that basically causes a vaccum leak at idle. Do away with breather if you have it, or take a hose from that hole back up to the air cleaner. Readjust the rockers using 1/2 to 3/4 turns after finger tight. Also. did you adjust them when both valves on that cylinder were completely closed? If not do so.

Breather cap always goes on the left bank (front) and the PCV valve always goes on the right bank (rear) unless your engine is a reverse rotation engine for front-wheel drive. This makes sure the air flow in the crankcase is aided by crankshaft rotation.

You may be right, but my car definitely runs less rich at idle like he told me it would. Technically, it still has a breather but from the breather, a hose runs to the port on the underside of the air cleaner. It made a difference in my car. The guy I got the info from runs the only speed shop in my city and has built motors for everybody I know. That doesn't make him a genius but I trust him. Have a good one.

This is how I adjusted my rockers and it worked perfect. This is the method for roller rockers. I guy with the screen name PKRWUD gave this info to me and it worked the first try. If I can do it anybody can do it. And I can't explain why to use a 1/4" ratchet.


1) Install all 16, and start the bolts, but don't tighten them.

2) Rotate the engine until the balancer reads TDC.

3) Check the rotor in the distributor, and verify that it is pointing at the
#1 wire on the cap. If it's not, rotate the engine 360 degrees. If the
distributor is out of the engine, or is off, you can find TDC on the
compression stroke by pulling the #1 spark plug, wadding up a paper towel as
small as you can, and jam it into the spark plug hole tightly. Rotate the
engine until the paper towel pops out. Then rotate it until the TDC mark and
the zero degree mark meet (the TDC mark should be very close when the paper
pops out). This is TDC on the compression stroke for the #1 cylinder.

4) With a 1/4" drive ratchet, tighten the following rockers until the rocker
tip is just snug against the valve:
Cylinder #1 intake and exhaust,
Cylinder #3 exhaust,
Cylinder #4 intake,
Cylinder #7 exhaust,
Cylinder #8 intake.

5) Now slowly tighten each of those with a torque wrench to 25 pounds. If
the bolt turns less than a quarter of a turn, you need longer pushrods. If
the bolt turns more than 1 full turn, you have to add shims until it can be
torqued to 25 pounds in the range of 1/4 to 1 full turn.

6) Rotate the engine 360 degrees, so the balancer reads TDC again.

7) With a 1/4" ratchet, tighten these rockers until the rocker tip is just
snug against the valve:
Cylinder #3 intake,
Cylinder #2 exhaust,
Cylinder #7 intake,
Cylinder #6 exhaust.

8) Tighten each of those to 25 pounds of torque, just like before.

9) Rotate the engine 90 degrees, and with the ratchet, tighten these rockers
until the rocker tip is just snug against the valve:
Cylinder #2 intake
Cylinder #4 exhaust
Cylinder #5 intake and exhaust
Cylinder #6 intake
Cylinder #8 exhaust

10) Tighten each of those to 25 pounds of torque, just like before.


That's it!

I understand, yours is a "closed" PCV system as opposed to the "open" PCV system I described (with just a breather cap on the left bank). The closed type like you have gets its input air from inside the air cleaner periphery. The advantage of this is if any gases escape from the breather, they are gobbled by the carburetor. In the "open" case these reverse flow gases are not burned rather escape to the atmosphere. The closed system is better environmentally and could cause the engine to run a tad bit richer under certain conditions. Your system is the "preferred" system but is not required by law on classic cars. The "open" system is simpler to implement.

Cool, that makes sense to me. Before I installed the hose, your eyes would burn whenever you were doing something under the hood or in the garage with it running. Thanks for explaining it better.

Not enough to account for the lack of performance here. There must be something else? Vacuum leak, timing problem, something major? There's something wrong?

Rev

On my 68 coupe (302 4V), my breather cap and PCV hose are reversed. The breather cap is on the right (rear) of the engine and the PCV hose is on the left (front) of the engine. Was like that when I got it. I know from the original engine manual they're reversed but was told (maybe incorrectly) it wouldn't matter. Car cranks and idles perfectly but hasn't been run in several years until I finish restoration (couple of months hopefully). Is this going to cause me any problems?

Read your Ford shop manual. The arrangement is always according to crankshaft rotation because it aids rather than opposes airflow through the engine. The only time its reversed is for reverse rotation engines (e.g., some front wheel drive vehicles, marine engines, etc.) Yes, yours still works but not as well as it could.

Okay. I pulled out the performance cam and reinstalled the stock one.
Stock measured 1 3/8 inches on the base circle and 1 3/4 on the lobe.
The perf. cam was 1 1/2 on the base circle and 1 3/4 on the lobe.

Seems my 289 needs the smaller base circle. The larger base is for newer engines.

Now back to valve adjustments. The book call for two turns after the pushrod is finger tight. Any reason not to do this??

I just checked and rechecked my '66 Ford Mustang shop manual for the 289 regular V-8 with hydraulic lifters. It said 3/4 turn after finger tight. There are 2 complete turns of the crank shaft necessary using the shop manual technique to adjust all the rockers.

Rev

I need to correct one thing. The book says 1 1/2 turns in my 65 manual with the 289 A block. 4 BBL 4 Speed.