We talked about how it's your opinion that performance is what sells drag racing. Do you think that if the majority of the tracks were all-concrete we would see better performances from the cars?
LB: I think you would see more consistent performance. I think the way the rules are today where we have a set gear ratio, a certain tire size and a rev limiter to keep the speeds down, the performance is going to be limited within a certain window. The consistency of the performance is directly related to the racing surface.
What else would you like to see, aside from improved track surfaces to make the show better? Should we be talking about the nitro percentage or some of the spec motor things that NHRA has done? Are there better ways to do what we're doing and have less parts carnage than we have?
LB: My opinion after looking back at my records is that I feel the engine life was much better when we ran 90% nitro in the tank. When the decision was made to go to 85%, I think it was a little bit of a knee-jerk reaction because of the Darrell Russell incident. NHRA's mindset was that we needed to do something quickly to slow the cars down and that's (85% nitro) the decision they made. Sometimes, though, when you go through life, you make decisions and after you made the decision a little time goes by and you look back and say to yourself, gee, that was the wrong decision. Maybe it (85% nitro) was the wrong decision and we need to go back to the way it was before. I'm a firm believer that the 90% was a more economical, predictable way to run these engines today.
You and I have talked before that you feel it would be less expensive at 90% nitro in the tank to race your team’s fuel cars than it is at 85%. Could you give me some hard data to support that claim?
LB: The data that I'm seeing indicates that on 85% we are consuming a lot more connecting rods and crankshafts than we did with 90%. The reason for that, and I'll go a little bit into the technical side of that, is to make the power needed to allow these cars to go 4.40's at 330 mph with 85% nitro (in the tank) versus 90%, there are three key elements. Number 1: you have to run higher compression because the (85%) fuel doesn't have enough energy in it. Number 2: we have to run higher (blower) boost, because, again, we don't have the energy in the fuel and you're trying to develop it with pressure. Number 3 is that you have to put more fuel in it (the engine) because you need to somehow get the same amount of pure nitro in (the cylinder) that's been diluted with 15% methanol as you were getting with a 10% methanol/nitro mixture.
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So, what transpires is you make actually more cylinder pressure at TDC with the 85% high compression, high blower boost, high volume fuel pump engine than you do with the 90% engine. The cylinder pressure is higher at top dead center, but the push on the piston as it leaves top dead center diminishes really fast because you don't have the energy in the fuel that continues to make the power to push the piston hard all the way to the bottom of the stroke.
Simply, you have a real hard bang right at the top of the stroke, harder than at 90%, but less of a push as it (piston) gets away from top dead center. When it's up around top dead center or a little afterwards, the connecting rod is not in position to rotate the crank very well and it want to compress the connecting rod and, instead of trying to rotate the crank, the rods try to push it out the bottom of the block. So, it tries to break the crankshaft in two and it tries to shorten the connecting rod. That has really weighed the cost of the engines today versus what it was on 90%, where we don’t have those issues as bad in the engine.
Are the engines restricted to rod length so that you can't change the rod angularity so the rods won’t be trying to drive the crank out of the main saddles and caps?
LB: We are only restricted with the bore and stroke; we're not restricted to the rod length, but there are certain limitations that you have within that 426-style motor. What we found was that on 85% we'd run as long of a rod as we could get in there to actually hold the piston up at top dead center for a long enough period of time. With the 90%, since you had a good hard push on it, you didn't have to hold very long at top dead center because the power was coming from the fuel, not the mechanical compression or the boost.
So, the big expense issue as far as engine damage is mostly related to the high rate of attrition regarding rods cranks?
LB: We are seeing a large amount of crankshaft failures. I don't know if people are aware of this, but in the final round of the Big Bud Shootout last year at Las Vegas, “Hot Rod” Fuller was racing Doug Kalitta. We put a brand new block and crank in for the final round and we were well ahead of Kalitta at the 1,000-foot clock, and we broke the crankshaft in two! On the very first run! So, not only was it a pretty catastrophic engine explosion, but it was the difference between winning the $100,000 for first and the $25,000 or whatever is was for second place. We had not experienced that type of damage to the engine when we ran 90%, lower compression engines with less blower boost and smaller fuel pumps. It was a totally different combination because we were getting power from the fuel, not from all the mechanical things involved.