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hey Martin, have you tried bringing the stages in sooner yet? are you still pulling alot of timing? what gear set in the tranny/rear end? O, and i can view your trace box that you sent me, so you can send it to someone that needs to view it.
 

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Discussion Starter #3
Eddie,

Haven't had a chance to do any testing yet, still making a few changes. The kits were set at launch, .5, and 1.3 secs on this pass. As you can see, it fell off 1500 rpm at the shift with all 3 on. Granted, there's not a lot of nitrous on the car, but 1500 at the shift is just a little too much I'd think?

Thanks for the help,
Martin
 

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that graph looks good to me...looks like it falls to 6300 so that is the lockup point of the converter...even if you shifted at 7000 it would still fall to 6300...does the motor pull good all the way to 7800?..mine does best shifted at 7400.

looks like it pulls back up to 7200 at 5.0sec...seems pretty good to me...if you want more i would add more jet..
 

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probably should give more info then to get a better idea whats happening.whats your engine/tranny/rear gear? how much nitrous are you using? whats the converter made for? big tire or small?
 

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Discussion Starter #6
that graph looks good to me...looks like it falls to 6300 so that is the lockup point of the converter...even if you shifted at 7000 it would still fall to 6300...does the motor pull good all the way to 7800?..mine does best shifted at 7400.

looks like it pulls back up to 7200 at 5.0sec...seems pretty good to me...if you want more i would add more jet..
Yes, the car pulls good all the way through. We actually had the electric shifter set at 7400 in the Biondo 450, I guess the shift points must be a little off. We had no idea we were spinning it this hard until we replayed the run. We're going to lower the shift point in the Biondo until we hit the target 7400 on the replay. The car went 1.16, 3.19, 4.95 @ 147 (trapped at 7200) this pass but as you can see by the graph it was slipping the tires each time we turned one on. I'm a little afraid to get much more agressive with it right now until we get the chassis worked out. I guess that the 1500 rpm drop at the shift may actually be helping me out right now, but it just seemed like a lot of drop to me.

Still trying to figure all this stuff out, thanks for the help.

Martin
 

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killer 60ft martin...i would like to know gear,tire and weight as well..my best is a 1.21 and i hope to go teens this year..are you willing to say how much nitrous jet you are running?i hope to run 4.80's this year..the tunnel ram sure picked mine up alot on motor.
 

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Discussion Starter #8
probably should give more info then to get a better idea whats happening.whats your engine/tranny/rear gear? how much nitrous are you using? whats the converter made for? big tire or small?
Nothing exotic, conventional headed BBC, 1.80 'glide, 4.10 gear, 29.5 x 10.5 tire, no bars. Car weight is 3010 lbs. race ready. This pass we had a .022n jet first stage at launch, .026n jet second stage at .6 and .032n et at 1.3 secs. 5 degrees launch retard ramping 2 secs, 5 degrees retard first stage, 5 degrees retard second stage and 10 degrees retard third stage for a total of 12 degrees in the motor at the traps (initial at 32).

Martin
 

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Nothing exotic, conventional headed BBC, 1.80 'glide, 4.10 gear, 29.5 x 10.5 tire, no bars. Car weight is 3010 lbs. race ready. This pass we had a .022n jet first stage at launch, .026n jet second stage at .6 and .032n et at 1.3 secs. 5 degrees launch retard ramping 2 secs, 5 degrees retard first stage, 5 degrees retard second stage and 10 degrees retard third stage for a total of 12 degrees in the motor at the traps (initial at 32).

Martin

this shows me smooth power application really makes a difference..i wish i could get that light..i am at 3280 race ready with 2 foggers with a 32n pill in both...i just might have to add a intake valley kit this year.lol....or build a mustang.
 

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From looking at your log I'd say maybe bring your 2nd kit in a little sooner to try to flatten out that dip in RPM that's showing right before the 2nd kit comes on. Also try shifting at a lower RPM...it might reduce that 1-2 shift RPM drop. Most people like to see a drop of 800-1000 on the shift. It looks like the converter wants to roll over (flash) about 5100 or so which is fairly tight. Maybe something that flashes to 5500-5800 might work a little better on the bottom. I don't think you are far off at all...we ran a 67 Nova at 3000 with a similar setup and the numbers were pretty close to yours from what I remember.
 

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my car on a tight track would like that tight of a converter. you can see its pulling the engine down after it flashes. If your gonna keep that tune in it i think it would pick up with alittle with a looser converter. mine did i have to turn mine up this year so im gonna try my tighter one with more power and see what happens. I was always told to look for 800-1000 drop on the shift on a nitrous set up
 

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Discussion Starter #13
Thanks for looking folks, sounds like I need to leave the converter alone for now and work on my chassis and tuneups.

Thanks again,

Martin
 

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Looks damn good to me Martin, realizing you are on a small tire, needing to control the wheel speed. Do you have a data logger to look at the DRPM & ACC? That would be great info to tune off of, i.e. whether you can apply more power. That tune-up with the smaller jets going to larger jets should work really well on a lose track too. And it seems your Converter, tranny gearing & rear gearing are working well together too. You COULD try to eliminate the Launch Retard 5* & 2.0 second Ramp on release of the TB, and see if the track will hold the additional power. If so, you should run faster.

I can't wait to go back out on a tighter track to try out the 2nd & 3rd stages. My 32N26F crossed way too low with same 29.5 tire (but mine is x 13.5) & 4.10 gear as you...crossed the 1/8 @ 6200 @ 135 @ 1/4 @ 6900 @ 165. My Hughes Converter is very tight stalling to 4300 Motor & flashing to about 5500 on 1st stags with about 1% slipplage at the 1/4. I weigh 3350#, and have a Glide 1.80 1st. My RPMS @ 7400 shift point drops to 5700, a decrease of 1700 RPMs! The 2nd stage will help me get the ERPM & DRPM up for sure. I am hoping to run 5.15 on 1 stage & 4.90s on 2 stages.

Good luck. I might try to make the Hub City Mardi Gras race, and if I do, I'll look ya up.
 

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Discussion Starter #15
We don't have any sort of data logger yet, haven't had the extra cash, but is is next on the list of must haves. I realize it's a shot in the dark without a driveshaft speed/rpm comparison, but we're managing for now. I'm a little afraid to lose the launch retard right now, if we can keep the high teen 60' times with it, I think my safest route may be to tighten the second and third stages up a little to see if we can go any faster with the current tune up. Then maybe step the second up a little from there.

By all means, if you make the Fat Tuesday race look us up in the pits. Always plenty of cold ones at our trailer. lol

Thanks again,
Martin
 

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You are probably right. That is a really nice 60', and the ET improvement is likely to be after the 60' by bringing in the current stages sooner, or jetting up a bit if the trackk will permit. Good job.
 

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Good question. My first reaction would be as a result of the additional timing retard with the activation of new stages.
 
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