183n it’s off nearly .2 in 60ft but is just down the whole way. Feels like it’s towing a heavy trailer. Just dead and struggles to get down track. Also I noticed just before this that it would stumble when I hit it to do a burn out or to go on the two step. I found a lot of slack in the accelerator pump linkage. Got that fixed and stumble is not as bad but still there.
Wooley did you call Kenny at PTC to see what he thinks? Possibly in the converter? Did you clean the idle bleeds? You'll get it I Hope to get to Reynolds this yr.
Did you verify the blades open all the way when you floor it since you had linkage issues? Would be nice if it’s that simple.
First thing I looked at was throttle blades, they are open. The converter is 3passes old. Car is same with new converter as old. Kenny is who worked with me on this converter but no, I have not called him back about it. Kenny is also who first suggested the stator tube. I had Godley refresh trans. It also has same three passes as converter so I am going to say the trans is good. Plan now is to change valve springs. I have borrowed another 7al/2 box to try if springs don’t fix it. I have another racer who will loan me his carburetor to try if needed. Last will be the ignition coil. While the heads are off I think I am going to pull timing cover just to satisfy my curiosity if the condition of the timing chain.
Carburetor on the car was taken apart and clean by first soaking for 30 minutes in carb cleaner then main body and metering blocks were also put in a sonic cleaner for five minutes before the last time I went to the track and made the three runs on new converter/fresh transmission.
Godley and Kenny. Rule that out of the equation. You got two of the best on the planet right there working on your stuff, Wooley. Godley builds ya a pump, you won't spin the stator. We've run Godley pumps on 3000 hp. Same with Kenny's work.
had a car once drop all sorts of ET/MPH. Looked for weeks and it turned out to be the positive battery cable was loose.
Car ran fine (no misses or anything detectable), but was down on ET/MPH. I always disconnected the negative and did check that in the weeks,,,but was too stupid to check the positive. Eventually, it got so loose that the car did not start and upon connecting a jumper cable I noticed it was loose. Charged it up in the lanes - next ET/MPH were back to normal.
Go over all the simple stuff was my lesson learned.
Just a update. I have changed the valve springs. One thing I did based on green1 comments on another thread about msd boxes. He uses the same box and coil I am. I sent the 7al2 box to msd while car was down to change springs. Msd reports multiple problems with the ign box. I have gotten the box re-installed into the car. The engine starts much easier and quicker than in a long time. (Years) I really think the msd box was my problem all along. As soon as I can get a test and tune day at the track I will find out. Hope for this Friday but with all the virus canceling things I don’t know. Got my fingers crossed hoping my cars performance and consistency will return.
My vote is valve springs. They go bad sitting up, MSD boxes shouldn't go bad sitting up. Did MSD mention what was wrong with the box? Timing would have to retard significantly to lose this much ET. I've had valve springs go dead and never know it car just acted like it was tired, no popping no interference just slow, no broke springs, just soft. Replace springs and back to normal. I never saw the 0.5 second loss you saw mine was more like 0.15 sec. on a 4.70's dragster.
Msd said it had two bad transistors along with two burnt resistors and the internal power supply was bad. Car is ready to go just nowhere to go test. I think springs are a big part of the issue. I can say that the car starts better now than in a long long time. Used to have to spin over forever to get it to fire up. Now it starts as fast as my daily driver truck. I will be happy to finally be done with starter kick back and broken flexplate teeth.
Kick backs cost me 6 flywheels and even more starters eventually broke callies drangonslayer crank. 565 BBC. Turns out my problem was bad plug wires. I know how frustrating that can be. Didn't realize an MSD box could go "bad" and still function but misbehave like you described.
Even though the MSD ignition box has been repaired, if you haven’t already, consider checking the spark plug wires, cap and rotor with a multimeter to verify continuity.
Having a second ignition box that you switch between every other year to verify operation can be a wise choice when racing.
The MSD 7al2 boxes were updated to the 7al2 Plus model in 2004.
Kris this happened to me a few years ago and I was running it that way for years. My car slowed up a couple tenths and stayed there for ever which I could never figure out. I built new motor and dyno numbers said it should go 8.4x in quarter in that car and best it did was 8.68. Built new car and took motor and ignition out of old car and put into new car, still a turd then the last race of the year three years ago it goes all weird on starting line and three passes later blows head gasket. Shop says looks like lean on NOS but I don’t have NOS. Send box back over winter and the next year I am four tenth faster with only new pistons and 10 more hp on dyno.
The Green1 your post on another thread is what prompted me to send the msd box in to be checked. I have had kick back problems for years. Replaced starters flex plates cutoff switch battery cables batteries you name it. Car had a new cap rotor and plugs. Haven’t changed wires yet but have some on hand if these check bad.
Well I try to share my problems to save other the long headaches I had. Yea I had kick back issues for year, carried spare starter and extra drives all the time. My motor made 884 hp on conservative dyno which when you consider the et it ran wasn’t even close to that. Now that it is fixed if you use Wallace calculator I am up to almost 950 by the et in same car but a little heavier and haven’t had a kickback since then. My best et in this car before was 5.51 and now it’s 5.21.
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