I'm with Dave, all the way, on this one. Unfortunatly I don't have a
dyno
other than the great white one in Utah, or Maxton as the case may be.
Anyway I have to do test runs cause that's all I have sometimes. So from
that testing I learned that the faster the 1/4 mile times the faster the
top speed. In my case if I controled the power application better from the
start (read that as no wheel spin) I could run 92% of my top speed at the
1/4 and pick up as much as 5 MPH at the top end (read that 224 vs 229 MPH).
Don't forget this is not a streamliner, no blower, no fuel and a small (304
cid) motor with a
carburetor.
I'm using a close ratio 4-speed, 2.32 1st., and its going to get even
closer on my next ride.
OK Tom that's one "speed secrete".
John Beckett
At 09:47 AM 4/23/99 -0400, Dave Dahlgren wrote:
>The real problem is that you run out of race track to play with. Your
>old 55 would go faster than 80 I hope. Mine did. The whole key point is
>to keep the engine in the power curve . If yours is 5000 rpm wide and
>flat then fine. Most are not. My years of experience tell me that the
>power curve of most engines is 2200 rpm wide where things really happen.
>The engine we run has am much smaller one than that. peak torque is at
>8800 and peak power at 9900. When you are not there you are just burning
>off the track distance. The faster you go the quicker you burn up the
>distance waiting to get to peak power. In my humble opinion you ought
>to be at 90 to 95 percent of what the car is capable of at the 1/4 and
>use the rest to get the last few percent. It has worked for me every
>time. I do not even like the push off as it burns off at least a 1/4
>mile that i could have used. To me this is a drag race with a very long
>timing trap. But only my opinion . I have tested this and every time I
>am faster at the 1/4 I am faster at the end. The only thing you may not
>like is the amount of time that the car is not accelerating at the end
>of the course. if your car is accelerating at the 4 mile marker you have
>left a bunch of speed in the trailer so to speak. Remember it is an
>average speed the faster you go in to the measured mile the faster your
>average. The only thing in favor of you way of doing it is that now to
>my knowledge all the passes are in the same direction. When it was the
>same physical mile had to be really going early on so that when you run
>in the other direction you do not get to the same physical spot too soon
>going too slow. Anyway I guess it is "po tay toes" and "po taa toes"...
>i spend a day or too with the dyno sheet from the engine and the
>computer figuring out the power available and the power required to go a
>certain speed. correct all for the weather and altitude. If the car does
>not break and slippage is in the range calculated car will go within 1
>or 2 mph of what we expect off the trailer. Have never made a 'warm up'
>or 'test pass' since the first one when car was new .. that one was 179
>on a 162 record... Told Goodman to just leg it out through second gear
>and shut it off on the short course so we could look it over before we
>run it out the back door. Now it is off the trailer, pull the trigger,
>go for it. you have to love the EFI the tune up is done when the engine
>starts, the gearing is done before we leave, and if the computer says we
>will not break a record we work on the car until it says we will, then
>we haul the car out to make a pass or two.
>
>Just my way of doing i am sure there are many that work, this one has
>never failed though.
>Regards,
>Dave Dahlgren
>
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