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How much weight to add #/ET question

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Old 05-12-2009, 10:34 AM
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Default How much weight to add #/ET question

OK, so I have a slow car and can't hang with the heads up guys so I mainly do index racing. This past weekend I tried to add weight to get to the 12.0 index. First round I added 100# and pulled an 11.77 @ 115, the next round of qualifyling I added another 40# (I had no more room to add more) and a more restrictive muffler and pulled and 11.88 @ 114 and ended up qualifying 2nd to last. On the first round elims I got knocked out because even plaing on and off the gas (3X) before the finish line I ran under with an 11.986 @ 108.

So I am trying to figure out how much weight I need to add to get closer to my intended index. Is there some sort of set theory/calculation to figure out how and where to best add weight?
Old 05-12-2009, 11:08 AM
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In my car I have found the general applies, .10 per 100#s
Old 05-12-2009, 11:28 AM
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Thanks Edgar, BTW what did you break on Sat?
Old 05-12-2009, 11:35 AM
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idler pulley came off, lost the belt, battery was too weak (10.8v) and all the bells and whistle warning prevented me from making a pass.

Hind sight, I should have bought a fresh battery like i planned last winter but could not decide which I wanted. I was going to buy one and go to the grove but figured with my luck so far this year, that would not be the only problem and I would have set a torch to the torch red car
Old 05-12-2009, 11:51 AM
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I hear ya, I had battery issue at the Grove on sunday myself, my 2+ year old pc680 decided that after it fully lost it's charge over this past winter that it doesn't want to hold a charge any more. I am expecting a few boxes from Summit tomorrow to do the full relocation and get a bigger battery, because I am tired of shutting it off in the lanes and not being able to restart it even after it sat on the charger the whole time between rounds...
Old 05-12-2009, 01:36 PM
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john unlock the converter the whole run and it will slow down a lot you know that
no weight needed
Old 05-12-2009, 01:40 PM
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Originally Posted by 1SlowFormula
I hear ya, I had battery issue at the Grove on sunday myself, my 2+ year old pc680 decided that after it fully lost it's charge over this past winter that it doesn't want to hold a charge any more. I am expecting a few boxes from Summit tomorrow to do the full relocation and get a bigger battery, because I am tired of shutting it off in the lanes and not being able to restart it even after it sat on the charger the whole time between rounds...
I wish I had the guts to move the battery but after my last fiasco with tools....I have given up
Old 05-12-2009, 01:57 PM
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Originally Posted by daniel6718
john unlock the converter the whole run and it will slow down a lot you know that
no weight needed
yeah my Nephew, who crews for me at the track, wanted to slow it down in the tune, but I didn't want to play with that as we had no other "practice" rounds to try and dial the tune in that day...

I am mainly looking for future races, when I have the tune set for the weather, but need to pull a few tenths without the finish line games...
Old 05-12-2009, 06:27 PM
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Drive the big end that way if it slows down you would have enough et to still take the stripe. I would try to set it up between 1192-1195. Maybe add another 50lbs to what you have now.
Old 05-12-2009, 10:37 PM
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Originally Posted by TA1364
Drive the big end that way if it slows down you would have enough et to still take the stripe. I would try to set it up between 1192-1195. Maybe add another 50lbs to what you have now.
y not ja bigger tire to gear it down to slow it down a bit
Old 05-13-2009, 04:07 AM
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im guessin unlocking your converter would cost you 4-6 tenths...i think you could change just hat one thing and make the car run what you want it to...no huge change in the tune...OR dail it in and make it lock at 70 or 90 ect to make it perfect then you can just change one thing in your tune and know what the car will run, change a few mph to make up for weather
Old 05-13-2009, 10:38 AM
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I know the sparetire well fits a 50lb sand bag perfect in our cars and covers in with that plastic piece(it will not move one bit)
make sure any balast you put in is very secure
you could put an adustable metal piece under the gas pettle if the class allows
if you run slicks with tubes take as much air out as you feel safe
rev limit during pass if rules allow you to
play around with launch rpm(watch your reaction times dont change too much)
deep stage(again watch reaction times)
Old 05-13-2009, 10:47 AM
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it is strange my reaction time is always slightly quicker in the elimination rounds then they were in qualifying, now they are not great by any means, but they are decent. .090 and .091 in qualifying and .071 in the elims and that is about average for me foot breaking on a pro tree...
Old 05-18-2009, 07:39 PM
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hey, I just came acrossed these from that race detailed above...

1st round qualifying for the index class (I got there late so I am the last car qualifying) I'm @ 8:55 http://www.youtube.com/watch?v=QVKKi2z3u0o

2nd round qualifying, I'm @ 2:54 http://www.youtube.com/watch?v=B58rJRdNkfQ

and 1st round eliminations I'm 50 seconds into this one http://www.youtube.com/watch?v=8sEUUnP2_n8


you really can find anything on youtube...
Old 05-18-2009, 08:01 PM
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.

I know a lot of guys that are doing the index thing.
They don't like to mess with tune or weight unless they absolutely have to.
They can scrub off a bunch of ET by quick shifting. Playing with weight or tune up, affects reaction time.

Good luck.

.




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