When checking lash on roller...
When checking lash on roller lifters, slide the feeler gauge perpendicular to the direction of the roller. If you run the feeler gauge in and out in the direction that the roller turns, it can give you a false feeling of lash clearance.
Timing Is Everything
A problem I see from guys who are new to racing is that they aren't sure how to set the timing on their engines. Let's say they have an aftermarket balancer with a degree tape on it that says 32 degrees. They also have an adjustable timing light whereby they can dial in 32 degrees on the back. Well, they've got 32 degrees in their heads, they set the timing light for 32 degrees, then mark the balancer on 32 and wind up with 64 degrees of timing.
Yes, the engine will crank and run with the timing set that far advanced. But when you go out on the track, it will knock the bearings out. I've seen it happen too many times.
Another tip I have for new racers is to always make sure you allow the engine to warm up properly. This is especially important for a new engine. You've got to let the water and oil temps come up to operating temperature before you start stressing the engine. When the fluid temps are still cold, that means that your bearing clearances are still tight also. Cold oil is thick, and when you combine that with tight bearings, you run the risk of not getting all the oil you need where you need it.
If you're racing an alcohol motor, it can be really tough to get that motor warmed up, especially early in the season when it's still cold outside. Guys will just let it sit and idle, and the motor will never warm up. Instead, it ends up running rich and milking the oil. If the carburetor has air bleeds on the side, you can actually lean out the air bleeds so that the carburetor won't run too rich while you are sitting at idle. Also, if you have a fan blade on the motor that's always spinning, I recommend putting a piece of cardboard in front of the radiator to block the flow of cool air. Both of those tricks help when you're trying to bring an alcohol motor up to temperature.
A third thing that you need to be aware of is how you service your K&N air filter. Filter problems are actually more common than you might think. Not too long ago, we had a guy bring his car back to us. He was down on power so we put his car on the chassis dyno to find out what was going on. He had already chased this power problem all over the place and replaced several thousand dollars worth of parts-ignition, carburetor, all kinds of stuff.
We finally found the problem almost by accident. I had taken off the filter because I wanted to watch the booster when we put the gas to it, and the engine suddenly picked back up. His K&N filter had gotten dirty, and he had decided to wash it with laundry detergent. That's the last thing you want to do because the detergent clogs up the gauze material of the filter, and then the filter won't breathe any air. K&N makes a filter cleaner that doesn't harm the filter material, and I recommend you use only that.
Make sure your air filter is properly sealed. This is vital if you are racing on dirt. Sometimes you won't get a good seal all the way around, between the filter and the filter cover, and it will allow dirt to be sucked in through that crack. You can seal that off by running a tiny lip of grease all the way around the filter on both the top and the bottom. This helps seal the filter to the cover so that the only way air can get into the engine is through the filter material.
Wells Racing Engines
Electric Power Equals Horsepower
Make sure that your engine is getting at least the 12 volts it is designed to run on. If you are running an MSD ignition, and the alternator is down and you aren't getting the voltage you need, your power is going to suffer. We encourage our customers to purchase a voltmeter and check regularly to make sure the alternator is putting out around 13.5 volts. All you have to do is ground one of your leads and then hold the other one to your alternator output. You have to rev up the engine a little. Those things don't start putting out until about 3,000 rpm. If you aren't getting around 13.5 volts, you probably need to replace your alternator.