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Discussion Starter #1
Quick update, as we are making progress with the change to the big tire, but not where we want to be just yet.

* Installed new Santhuffs rear shocks & 100# springs;
* 1.80 1st gear from 1.69 (same 4.29 rear gear);
* IC now at 58" & 7" (slightly longer & higher);
* Larger 36n plenum kit on 1st with 2nd 32n fogger on 2nd;
* Hoosier 33x16x15 tires (108" rollout), 6#;
* Bottle pressure lower than normal @ about 825#;
* 4000 launch chip vs. usual 4800 (MSD box was not set right);

Video of 2nd run: Car launched well, but still crunching the tires, then went right hard down track @ 2 seconds (think the track was loose);

http://s1132.photobucket.com/user/f...051F64981AB27_zps175a2d0d.mp4.html?sort=3&o=0

60' is 1.120, not what we are shooting for, but OK in these air & track conditions.

Run1 Graph: Left good, went right down track, peddled it, n20 on & off again, still 3.12 4.70 156 lifting at 6.4 seconds 7.26 179 scrubbing about 17 MPH.


Run3 Graph: 2nd stage on @ .35 seconds vs. 6 in Run 1. All good until the car again moved right & did not shift in to high gear, 8000 when I lifted.


The data seems to suggest that we need more wheel speed sooner in the run, as we are not close to getting up on the tire, even with two stages on in .35 seconds.

We will make a few small changes the next time out, besides fixing the tranny;

* -6* & -8* vs. -8* & -6* (16* total);
* 4800 Launch RPM vs. 4000;
* Bottle pressure closer to 900#;

IF we can get this to work, & get down the track, we should be able to bring the 3rd "smallish" stage 26n20f in @ .60.

We'll see. Any thoughts are welcomed.
 

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Discussion Starter #3
Thanks Steve, will post when I get home at lunch today.

The early #s (DRPM, ERPM, ACC) definitely got higher as I turned the 2nd kit on sooner from .65 in Run 1 to .35 in Run 3, & the graph looked better too. Remember too, the GOW was about 130, ambient temp about 100*, & track temp about 130*, so we are relatively down on power as compared to just decent air conditions. The Converter is a bolt together Super Mega Coan that came out of the 02 Camaro with 738 cid & Glide. On Run 1 when I lifted & peddled, & it recovered & went 4.70 @ 156, the slippage was still respectable 8%...I think it will go to 5% when I make a clean pass...of course, it locked up 1:1 long before the 1/4...even scrubbing about 16 MPH.

Feel like we are getting closer...
 

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Discussion Starter #4
Steve,

Run 1 with 2nd stage on @ .60;

DRPM
.10 198
.20 250
.40 2326
.50 2701
.75 2408

Run 3 with 2nd stage on @ .35;

DRPM
.10 1057
.20 1291
.40 2832
.50 3061
.75 3265

Remember, big tire, back half car, 2900#. Also note air & track conditions...South Louisiana in the summer time...LOL.
 

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Discussion Starter #7
Jamie, you might be right. The track did get hotter...we made the 1st Run at 11:03, & the 3rd Run in the heat of the day at 12:33, when the track temp was hotter. The video was actually Run 2 where the #s were in between Run 1 & Run 3. Run 1 was the best 60', although Runs 2 & 3 might have hit the 60' beam under the car. , My "seat of the pants" driver perspective feels as though the tire is rolling over itself, as it always has, & is no where near getting "on top of the tire". I wish I had taken the time to position the GoPro on the rear tire, but we were rushed to make each Q round, while trying to beat the rain.

Thank you for your comment.
 

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Hey Ronnie, You took the 1.69 gear back out and put a 1.80 back in?? I thought Monte swears by the 1.69
 

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It was just a suggestion every car/combo takes a different setup. Good luck figuring it out try slowing it down a little down low .2-.5 and the 60 will improve!
 

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Discussion Starter #12
Thanks everyone. Trial & error. Hope to be back testing Saturday, weather permitting.

Gangster, the 1.69, & even numerically lower 1st gear, would be more appropriate with a smaller tire. This big tire & n20 converter need a higher SLR to try to get the tire rotating on launch. Coan has also been working with me to advise us on the right overall gearing & converter combo...the converter definitely likes the lower 4.29 rear gearing (higher SLR). The 156 MPH on a "lifted & peddled" run with a weak 60' tells me we are making good power, & getting it to the ground by the 1/8 stripe fairly efficiently. The ET can only improve with a better 60', & that is what we are focusing on now. Track & air conditions at this time of year in south Louisiana do not make this easy.

Again, I think we are making progress...work in process.
 

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Just my opinion but tire speed is way fast!!
This is my thoughts too. In most places you can see the tire trying to run out from under the car until it finally does and the run becomes a peddle or abort..

On a track like it seems you are commonly racing on you cannot get down with spinning the tire the whole way. In my opinion that car with less nitrous and better control would be way faster. That car should go at least 4.50's on two small systems with the parts you have..

I'm not trying to be an ass at all, but just curious in the last say 20 attempts down track how many have been FULL passes with out peddling, shaking, and so on ?? I tell many of the guys I talk to you will learn more going DOWN the track slow, then you will beating the tire off the car and aborting.. Just my two cents.. SJ
 

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Discussion Starter #15
Thanks Steve. You may well be right about the wheel speed. Ask 12 people about this, & you will get 6 on one side & a 1/2 dozen on the other. It would take me too long to list ALL of the issues we have had with this car over the last several months. It would take but a second to tell you how many full passes we have made in the last several trips to the track. We work way too hard, & spend way too much money not to see better results. Mechanical issues, i.e. mostly the tranny, have plaqued us.,,no doubt worsened by tire shake. Nobody said it was going to be a rose garden...LOL. Most of this has been "self-inflected" by choosing to go to the big tire from the Ws, & to the 5" BS 706 from the 638, but that is part of the learning curve. The smaller 638 went 1.10 3.06 4.62 156 7.13 198 @ 2950# on 2 kits on Ws, but we opted to try the larger Fulton 706. Hindsight is always 20/20. Hopefully we have figured out the gearing, tranny, converter combo issues, & with the new Santhuffs on the rear, have moved on from shaking to getting down the track. I can only learn from the rear mirror, but focus looking forward...
 

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Fofo it might be better for you to find someone that has a little more knowledge (not saying your not smart) on what you are trying to accomplish and they could help you get where your trying to get with your program quicker which in turn could save you time and money! Good luck to you and hope you get this thing figured out!!!
 

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I agree and I think too many people get caught up in numbers thinking that's where something needs to be. You need engine rpm for wheel speed and mph depending on gear. I've mentioned this before but I just don't think a 4.29 is right with a 33 tire. Maybe im wrong with that large of a motor and torque. I think people focus too much on getting the tightest converter % possible thinking that's only way. I'm not saying more is better just that you can still go fast. I'm gonna catch slack for that comment but I've been 153 mph with 15% slippage and only 750 rpm drop on shift weighing 3300lb. Your car at 2950 and that much power should be way faster than 156 mph to the 1/8
 

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Discussion Starter #18
The original builder of the car, Rick Stevens with Rick Stevens Racecars, is helping me, along with a certain person on YB that I'd rather not mention by name. We are making progress. I do not have the luxury of a seasoned crew, & I am lucky if I can get someone to drive the golf cart for me, & that leaves me running around like a chicken with its head cut off trying to get done what needs to be done. Finding crew help is always a challenge. I cannot listen to everyone, because everyone has a different opinion, & many times their combo is not my combo. Needless to say, this is a good case of "easier said than done".

The car will go 165-168 to the 1/8 by the time we figure things out in better air & track. It went 156 last time out with a shitty 60', lifting & peddling, n20 systems on & off, in 130 GOW & 130* track...see Graph of Run 1 I posted. The car will also go 6.90s @ 200, again, when we get things sorted. Glass half full...
 

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fofo looks like you are getting further down the track !!
like steve said the more full passes ( never thought I would say this ) the better data !!!!!!!!
keep on keeping on man .
 

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Paying a good chassis person for a weekend will save you a LOT of money & time. You can learn more in that weekend than it would take you a year or more of "experimenting" & wearing out your equipment not to mention all the frustration & disappointment involved. Look at most of the pro teams or other top running teams...they aren't doing it themselves, they have people with many years of experience helping out. Been there done that myself. Doing it all yourself is nice and rewarding if things go right but sometimes learning from the pros makes for a much more fun experience in a much shorter time span.
 
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