Drove down Fri. night to dial in the tree for Sat. race. Once the car was set put in the big pill for play and again c-u-later came through with this video. The video has given me great help trying to diagniose the car leaving status which I'm trying to get sorted out now so it's even more deadly. Meet Rouge86 also while I was there-local town Fri. night while we were searching for a hotel had hundreds of cars cruising by the mall-so we vowed we'd make a few passes Sat. before we came home Sat. night. That's where i met Rouge, very nice guy, so this summer has been great meeeing all these fellas in person.

Hopefully the link will work.

Stephen & 10.90street car, you know the other side of the coin with this clip, so please jump in with anything you see also.

http://nvlsonline.org/3rdgen/joshm/j...ch_upclose.mpg

 

Not sure what to comment. I wish I had video of my car to watch.

The thing I notice is watching the launch in slow motion. Going forward and back just as you launch you can see the rear tires really bite in then lift. That could be just the tire sidewall compression but it is noticable. How much air pressure? Mine probably does the same thing.

 

Hey, nice vid! I was wondering if you noticed the 600cc crotch rocket that reved at you before you left saturday night when i was behind ya in the 4th gen? Needless to say i don't think he knew what he was dealing with Also had a few people wondering what that smell was... hehe gotta love cam 2.

i went down and raced sunday... the air was really crappy. Went out second round of trophy when i broke out, ran a 8.70 on a .72

But it was a good weekend, good to talk to you and c-u-later! I'll see ya at cordova

 

With these tires and tubes I'm running 11psi.

So what I'm seeing as "basketballing" you think may just be tire shock when it takes the hit and sticks? Wish I would've had a strip on the sidewall to watch true rotation.

Rogue66, we posted bout the same time. I did'nt hear the rocket revving at me, cant hear too much with the loud mufflers and stereo turned up to tune the motor sound out, LOL.

Glad ya made it that far. I was gonna head to our NHRA track, but we got home late and were worn out from Sat. in the sun so we called it off last minute. All day Sunday it was windy as helll and everytime I gust came up I wondered how guys were doing on their dial

Had a great time at Eddyville even though I stepped on my dic, always fun going new places to race. Glad we made the descion to stop and make a few laps too, fun to see people actually having a place to cruise and it was nice you stopped by to shoot the breeze. All in all a great trip I'll be repeating in the future, very very nice facility there, everything I've ever heard about it. Just too bad he did'nt have another 1/8mi. added on for a complete 1320ft He'd have to turn cars away on race day.

 

i've watched a few of these things now from my friendsat the track. seems to me that the car is....

1.staging
2. sidewall wrinkles
3. as the front starts to come up the rear lifts
4. then the car launches straight and level

I wouldn't think the rear end coming up as necessarily a bad thing, because if the rear lifts as the front lifts then the tires must be planting well to allow the suspension to unload a little as it carries the front end.

 

Something has changed since last yr with the small motor, last yr I had cuts in the tread section from the wheel well lip going into the tire patch, weight transfer was that prevailiant.

I changed to the shorter jegster torque arm and air bags, now it looks to me like you said the rear is serparating. It really does'nt roll over as bad as it feels like in the car, but it's obvious the driver side rear wheel well is not getting any closer to the tire once I let go of the button.

 

I think mine squats too much. I moved my ladder bars up a hole but never got a chance to get any track testing before I pulled the engine.

 

With the torque arm, is'nt it he same principal as a ladder bar, where the front mounts that is the IC? I'm thinking with shorter torque arm and higher mounting point it's transfering the load right to the tires instead of the chasis, if I could make another mounting point to lower the front of the torque arm, it should make the chasis take more of the hit instaed of the tires?

 

When the rear squats, it is doing so at the expense of down-force on the tires.

Think about the old "to every action, there is an equal and opposite reaction" - a simplification of Newton's 2nd law. Another way to put it is in order for something to move, it has to be acted upon by a force. Gravity is always with us here on Terra Firma, so the body of the car is being acted upon in a downward direction by that force. In order to stay off the ground, the tires & suspension push it up - the opposite force in this simplified case, and the body is therefore pushing the tires down on the ground.

If the body heads downwards when you launch, that means the suspension is not pushing up as hard - and therefore there is less force pushing the tires down.

A shorter torque arm is going to push up on the body farther back - that's a good thing when you think about it. When you launch and the back end goes up, that means the body is pushing down on the tires harder - which is a good thing for the tires and traction. A long torque arm is going to push the front end up at launch - which doesn't have as direct an effect of pushing the tires down.

I'm probably not explaining that very well, but the simple truth is that the rear end going up on launch is a better thing than the front end going up on launch.

 

Suprisingly that makes sense,LOL I've just neer had a car with this kind of power and everything I thought I knew before has changed. Not so much changed, but opened up a new chapter of tuning I never had to deal with before.

Even with the truck, trying to get that dialed in with the hp that made and then the big weight baised issue with basically none out back, made figureing that out a challenge. Guess once again it's a matter of how much loose change is rattling around in my pocket to remedy the situation.

 

I don't mean to be impertinent, and admittedly the resolution I can get of your video isn't very good, but is that his win light coming on????

 

Yeah, lol that run was taken at the Fri. night T&T, we went down a day early to make sure everything I do at our track would work on this track, which it did. So I took my race transbrake pill out and put in the 4200 pill for play. My buddies car's been broken all yr and he was my PB for the weekend so I let him make a pass since the track was hooking. Last time he drove it with the big pill was at a night street race with more sand than VHT on the track. He was grinn'n ear to ear when he got back and vows to never come back until he has a transbrake in his car,LOL.

The car beside me was a late 80's early 90's fox body completely gutted Mod. car. So given the fact I'm an F-body with full interior heavy as a tank and fully streetable gives me the needed "break" for getting beat heads up

 

Interesting. I just happened to be flipping through Feb 27, 2004 issue of National Dragster. There's an article on roll control.

"During the period of launch amazing things happen under the car. The driveshaft applies force to the pinion and ring gear. If at this moment you could watch the rear housing and suspension closely from a rear angle behind the car you'll see that the initial hit of power causes the left side of the housing to plant downward due to the rotational forces of the ring gear"

It goes on to state other stuff like the left front wheel coming up etc.

That must be what I see in your video. That transbrake hit is so hard that the diff is driving that left rear tire into the ground with a lot of force. An adjustable rear roll bar (roll control) that would allow you to preload one side might be the answer although it's recommended to not set a preload.

I'm not sure if I would need one or not. Ladder bars make a stiff suspension already. Lift one wheel and the other wants to also lift. I suppose there's still some flex but not as much as a more normal style suspension. I've seen launch pictures of my car and both wheels lift the same.

 

I'm goin gto give Don at S&W a shout next week, he says they sell the same anti-roll bar as the one Wolfe makes 3rd gen specific, if so I'm ordering one. I think before I update the other parts, I'm going to go with my typical buy parts and see results before moving on, this way I can have some real world data.

I know it'll be 100% better than the sway bar out back since it's not allowing the body to rotate at all, minimal at best, especially judging by the pics on 10.90 street car web page-that a huge improvement IMO.

My friend was over today, and all last yr he could'nt stick his BBC in his 78 malibu. The car used to squat on launch until he installed a set of SSM lower control arms, then the rear would not budge-tires took all the hit and they would spin/unload something feirce. Since it was a factory "4 link" type we plotted out the IC and it was waay back-the guy that built his 9" failed to tell him he raised the upper control arm mounts a little- so the plot lines came out in the back seat butt cushion area, damnn near on top of the tires. His motor blew before we had the chance to try the stock but newly boxed factory LCA which woulkd've changed the IC by leveling the LCA out and placing the IC at about the back of the transmission area instead of where the back seat cushion was.

So I do agree with the fact like 57kid pointed out about the shorter arm forcing the tires into the ground with the equal pressure upward and downward-(too late to re-type politically correct)- There has to be a point where too much shock is too much as these tires can only take soo much before they're taxed. I strongly believe with the set-up I'm running, if the anti-roll bar does'nt do the trick-or help-, I'm going to re-fab the bracket on the torque arm mount in the tranny tunnel to give it some adjustibility since in essence that's instant center, just like a ladder bar.

If the lines are plotted out, lowering the mounting tab for the front of the torque arm "should" essencially move the IC forward and transfer more energy into the chasis and take some away from the tire which I think would help. I'd like to get this stuff figured out now before we step upto a bigger mill

If my "thinking" sounds outta line, step in and plead-I'm all ears right now!!

Just wish I could win the lottery, then I would'nt have any problems Could afford race parts on a as needed basis

 

I think moving my ladder bars up a hole will help. They're now parallel to the ground. I had them down a hole to soften the hit on the tires due to poor track conditions so the angle was going below the car. I also cut a coil out of the rear springs at the same time I raised the ladder bars back up. When I got rid of all that glass off the rear of the car last winter, it came up quite a bit. Cutting the coils dropped the back end back down but I don't know if it was enough or not.

I haven't weighed the rear hatch yet (still in the garage collecting dust) but I'd say the glass and deck lid are probably in the 60-70 pound range. Might even be close to 100. It's damn heavy to lift. The 1/8" Lexan and sheet of aluminum for a deck lid must be close to 10 pounds at the most. Not a suggested modification to do for anyone unless they intend to have a track only car and it's never stored outside. The inside of my car is no longer waterproof. Lots of holes drilled in the floor to let the water out when I get stuck in the rain at the track.