Project "Snotty 289" update (long)

[jdean]

The cam finally came, and we wrenched all day Saturday to get the motor back together. Jim, Steve (my brother), Richard Parker and me all worked on it. One of the things we re-did was the alternator bracket to make a simpler look. I took the old bracket and cut and welded it to change the angle. Looks good, pics later.

We had previously mocked up the heads to check for proper pushrods, which we custom ordered. They needed to be shorter than previous. We also used clay to measure piston to valve clearance, which was over .120 which is plenty.

By Saturday I already had the new heads on and torque'd down. In Jim's car we are lucky we can raise the engine off the mounts enough to clear the chassis and install the cam with the engine in the car.

So we put in the cam, put in new roller lifters, new Scorpion roller rockers, new pushrods new intake and new carburetor.

We then "ran the valves" by adjusting the rockers/lifters to one-half turn past the initial pushrod contact.

We put a little gasoline into the top of the carb and it fired up on about the second try.
It was good we put on a new fuel pressure gauge to give us proof and confidence that fuel was being delivered to the carb.

The idle was way high, so we set it lower and then used a timing light to set the timing. I set it at initial 15 degrees for a start. This gave a max of 35 degrees which was all in by 2500 RPM.

Initial Problems - There was way too much valve noise. We later took off the valve covers to inspect. Most of the lifters were pumped up solid as a rock. No give at all. We let them set for a few hours to see if they would bleed down......they did not, even after sitting all night! This was puzzling, but we figured out a way to safely experiment with them. I took off the passenger side cover and reset the valves on that side to only 1/4 turn vs. the 1/2 we tried. Same noisiness when we started it up. Then I went to the driver side and added 1/2 turn....for a total of one full turn. This time it quieted down a lot. So later I did the same full turn to the passenger side.....noise is all but gone.

One other issue is that the thing does not want to settle into an idle without dying half the time. When you clutch it coming to a stop or slow turn, it tends to die. After setting the idle air bleeds twice, and the curb idle.......it still just does not want to idle, it is either way too high or it dies. I am open to suggestions on this one....brand new Holley 670 Street Avenger. These should be "plug and play".

The good news......it sounds very raunchy, revs instantaneously and pulls like a freight train all the way to high 5,000s. Runs very well pushing it hard through the gears.....just does not want to idle ;-(

We may just for process of elimination put the old 600 CFM carb back on to see if there is better idle behavior.

[SSSammy]

Well .. idle mix, John. Or is the elec choke working correctly? My 4150HP doesn't like to idle till it gets warmed up, but it has no choke. Additional suspects: coil, low battery, just brain storming .. good idea to put the old carb back on, easy to do. Are we gonna see it Sat????

Sam

[Joe Wicked]

I had an old 460 that did the same thing with a new carb. I could not figure it out. Either I would have an idle that was way too high, or it would die. Finally took it back off and exchanged it with another. No problems then. I took the carb back and had to wait for another to come in. I don't know for sure what was wrong, but the guy was not surprised at all when I described my problem with it. Seemed to be a pretty common problem/complaint with Holley Carbs. This was 10 years ago, so I don't know if it relates or not.