94 Spitzer 235" hardtail problem

Old 09-29-2007, 11:57 AM
  #1  
Birddog95
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Default 94 Spitzer 235" hardtail problem

Hey all. Been only racing dragster for a year now (door car for 12) and have been having problems getting down the track. Before we freshen the car (ran 8.26 @ 164) the car hooked great. Now that it's been freshened (runs 8.08 @167) the car 'chirps' all the way down the track. We purchased new Hoosiers to see if the tire was the problem but it still remains. Now one thing I did do was added 10 lbs to the front ballast tank cause we were pulling the front tires 3" or so. Is it possible that I'm now on the edge of the chassis capabilities or is it now that I don't have enough and need more power to keep the tires planted the whole way? Any suggestions would be appriciated. Oh ya, our season is now done since we kicked a rod- I'm blaming the loading and un-loading of the tires down the track on this one :wink:
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Old 09-29-2007, 05:41 PM
  #2  
Bubstr
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First off. I got to say you do one wail of a job freshening up something. .02 tenths, that thing must have been in bad shape. The Mph didn't go up but 3 MPH though. If nothing else in the engine was changed, It sounds like your running it out the big end way on the high side of th power curve or it has a wing with the frontal area of a mainsail on the Yankee Clipper.

Al though there is no positive way to solve your problem over the internet, there are a couple areas you may want to look at. First you have gained HP and it seems mostly on the lower end of your curve. Second you have changed your center of gravity point. Not sure where it went but 10 lbs could move it considerable depending where the 10 lbs went and where the center of gravity was, and the total weight of the car. Third is, is your tire pressure matched to your new power levels and change in center of gravity? Best way to check tire pressures is with a pyrometer, even across the tire and even side to side. Well as close as you can get.

The thing to remember is your chassis and tire pressures are you springs and shocks you ran for twelve years. This isn't bad, it's just different in the same kinda way.
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Old 09-30-2007, 08:59 PM
  #3  
Birddog95
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I learned a few things this weekend. We ran a hoosier C07 tire last year and went to a D09 this year. A fellow told me that the 09 is for suspension cars and the 07 is best for hard tails??? We didn't change any parts (other than the carb) to make the extra power. We found the piston to head clearance was .012 :shock: pushrods were .080 to long and tons of blow by on the rings. Pretty easy to pick up .2 with these problems. The weight is right on the nose which probably decrease a fair bit of rear wheel weight. I'm contiplaiting doing a 4 link conversion. I don't know if this is a good Idea or is it better just to get a different chassis. :?
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Old 10-09-2007, 06:07 PM
  #4  
johnracer
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Default My 2 cents...

Most of my dragster experience, ok, all of my dragster experience is in a FED. However, a hardtail RED may react in a similar fasion. My FED would "chirp" as you decribed if the balance of ballast, tire pressure and power was off; even a little. Personally I wouldn't add ballast for a 3" wheelstand. Try a 10 footer......anyway, if I tried to get my FED to "deadhook" it would chirp. Adding a little front ballast or a little more tire pressure would usually cure it. What happens is the front pops up too quickly for the momentum to carry it, so it drops hard and causes the chassis to ocillate or bounce causing the chirp and a loss of ET as well. If you get the correct balance, the front will rise and fall smoothly. In my FED, any attempt to keep the front end on the ground (too much ballast) would cause it to spin but not chirp.
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