My first outing with the car was quite successful and met my expectations. 6.51 @ almost 105 in the 1/8 mile.
One thing I noticed was that on a couple of runs, the car "seemed" a little flat out of the hole, even thought the 60ft times were still good.
I wondered about the accel pump tuning.
I ran the engine just as it came off the dyno...or so I thought.
The week after the race, I checked a few things. Turned out that I had set the timing for 45 total. Ouch! Good thing I had race fuel mixed with the pump gas. The car might have liked this setup in low gear....but not beyond that. The reason I goofed? Well, I tightened the distributor right before I left for the track, w/o checking to make sure the dist didn't move. Mistake! I had 2 gaskets under the dist...and they crush a bit when you crank it down and guess which way the timing moves?
I also discovered that I had the float levels too high....by a fair amount. Lesson # 2....make sure the car is on level ground when setting the floats. My driveway is sloped.......and so is my forehead now!
Because I had struggled with getting the advance curve right, and because I really didn't want to run locked out timing, I spent the better part of Sat making a new adv limiting bushing for the dist. (stock GM with a Unilite) I wanted to be able to set initial to around 30, and I got lucky and nailed it. Now I have the initial at 28, and the total at 38, less than the engine wanted on the dyno, but a good place to start. It just wasn't happy with 20 initial, and I had to add heavy springs to get it to quit advancing at idle. That slowed the total to around 3500.
I now get total before 3000, and the timing is stable up to about 1500.
The car seems to start fine, but I think I'll get it spinning before hitting the ignition just to be safe.
I reset the floats, in the garage, which is level! (slaps forehead again)
And I jetted up the carb 1 number front and back from the dyno jets. My engine builder thinks 2 sizes will be required, but I want to sneak up on it.
I didn't mess with the accel pumps. I need to see how it works with the float level set right to start with. It could have been sloshing fuel from the primary vent, which will make a car lazy out of the hole. At least in my experience.
I'll give the car another 1/8 mile whirl this Wed, and go from there.
Expected temp will be in the low 80's...but we race in the evening, so it cools down as we go along. Last time out temp was around 80 first run.
Zero predictions....but I hope it goes in the 6.40's.
One final thing.
I seemed to be having problems with a few rockers wearing heavier on one side of the roler tip on a few valves. I though this had to be the heads fault. Well, before I went racing, I swapped a "bad" rocker to a good valve, expecting the problem to follow the valve. Well, it didn't! The valve with the problem rocker looks perfect now...so I may actually have a problem with a few of the rockers. I'll try to get 4 new rockers and see where it goes from there. They are Crower SS BTW. I'd sure rather have this be a rocker problem than a head problem. Did I word all of this correct?
Ron
One thing I noticed was that on a couple of runs, the car "seemed" a little flat out of the hole, even thought the 60ft times were still good.
I wondered about the accel pump tuning.
I ran the engine just as it came off the dyno...or so I thought.
The week after the race, I checked a few things. Turned out that I had set the timing for 45 total. Ouch! Good thing I had race fuel mixed with the pump gas. The car might have liked this setup in low gear....but not beyond that. The reason I goofed? Well, I tightened the distributor right before I left for the track, w/o checking to make sure the dist didn't move. Mistake! I had 2 gaskets under the dist...and they crush a bit when you crank it down and guess which way the timing moves?
I also discovered that I had the float levels too high....by a fair amount. Lesson # 2....make sure the car is on level ground when setting the floats. My driveway is sloped.......and so is my forehead now!
Because I had struggled with getting the advance curve right, and because I really didn't want to run locked out timing, I spent the better part of Sat making a new adv limiting bushing for the dist. (stock GM with a Unilite) I wanted to be able to set initial to around 30, and I got lucky and nailed it. Now I have the initial at 28, and the total at 38, less than the engine wanted on the dyno, but a good place to start. It just wasn't happy with 20 initial, and I had to add heavy springs to get it to quit advancing at idle. That slowed the total to around 3500.
I now get total before 3000, and the timing is stable up to about 1500.
The car seems to start fine, but I think I'll get it spinning before hitting the ignition just to be safe.
I reset the floats, in the garage, which is level! (slaps forehead again)
And I jetted up the carb 1 number front and back from the dyno jets. My engine builder thinks 2 sizes will be required, but I want to sneak up on it.
I didn't mess with the accel pumps. I need to see how it works with the float level set right to start with. It could have been sloshing fuel from the primary vent, which will make a car lazy out of the hole. At least in my experience.
I'll give the car another 1/8 mile whirl this Wed, and go from there.
Expected temp will be in the low 80's...but we race in the evening, so it cools down as we go along. Last time out temp was around 80 first run.
Zero predictions....but I hope it goes in the 6.40's.
One final thing.
I seemed to be having problems with a few rockers wearing heavier on one side of the roler tip on a few valves. I though this had to be the heads fault. Well, before I went racing, I swapped a "bad" rocker to a good valve, expecting the problem to follow the valve. Well, it didn't! The valve with the problem rocker looks perfect now...so I may actually have a problem with a few of the rockers. I'll try to get 4 new rockers and see where it goes from there. They are Crower SS BTW. I'd sure rather have this be a rocker problem than a head problem. Did I word all of this correct?
Ron
