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Adjusting compression and rebound

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Old 08-18-2013, 10:52 PM
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Originally Posted by Martin@Tick
Don't be afraid to side step the clutch at 5-6k RPM. You've got good parts that will take the abuse.
Is it usually faster to side step vs a slight slip even with slicks? I noticed when I launch my car hard I still get a tiny bit of spin but with a slick that's ideal right?
Old 08-18-2013, 11:14 PM
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It depends on the clutch. With the clutch you have, you want to side step the clutch and let the tire slip off the starting line. You want the suspension loose enough to plant the tire hard and flatten it out some, but at the same time in the rear you want it tight enough to gather wheel speed and keep the nose of the car up and weight transferred on the rear tires. This will allow the 330' to be the fastest it can be with a clutch car.

A lot of times guys with 6 speeds focus on the 60' too much and launch the car with too much bite in the suspension where it dead hooks and hits the 60' hard but the nose drops and it loses wheel speed after the 60'. Basically you want the RPM's to stay up in the engine's power band until the tire stands up from the wheel speed you've generated.

This will be fastest to the 330' and ultimately down track.
Old 08-18-2013, 11:26 PM
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Awesome info, I'm glad you are willing to share this with everyone! Once I get the 2 step in I'll record some launches and hopefully I'll be able to get it dialed in. I've been going by feel so far, and right now I've got the comp where you said to set it and rebound is at 7 in the rear, I may drop down to 5 to get it to plant a bit harder. Would you set the shock differently for an unprepped street vs the track? At what point would you want to change tire pressure to adjust spin vs shock settings?
Old 08-19-2013, 08:57 AM
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On an un prepped street I would drop tire pressure and loosen extension.

On the tire pressure vs. shock settings you need to go by what your go-pro is telling you. If the tire is distorted badly and wadded up, add pressure.

That said, you can control how badly the slick gets wadded up with compression in your shock settings as well.

It's all a fine line and there is no blanket statement that will get you down the track.
Old 08-19-2013, 03:09 PM
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Right on, so for the 330' mark what would be considered a good time there? Like you mentioned all I've really read (aside from your posts) are about the 60' coming down but the 330 is rarely mentioned.
Old 08-19-2013, 04:28 PM
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Originally Posted by fly boy_1
Right on, so for the 330' mark what would be considered a good time there? Like you mentioned all I've really read (aside from your posts) are about the 60' coming down but the 330 is rarely mentioned.
On a 7.0 pass or close to it, I would say the 330' is going to be in the 4.45 range. I found an old time slip where it went 6.85 to the 1/8th and the 330' was 4.358. On that pass the 60' was 1.402. Obviously, it all depends on your combination but that should be a ball park figure. Hope this helps. Good luck to all on your times.
Old 08-19-2013, 05:51 PM
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i noticed the 60-330 thing when I was still learning with the shock setups, and the car would do a little bunny hop wheelie, then the nose or airdamn would drip the 60 (it wasnt the tire) so the 60 would look really good but the 330, 1/8 would be the same or slower.

radial are lot different the slicks, I was almost at the end the the rear shock range, full stiff comp or 2-3 clicks from. To have the rim push the tire into the pavement, didn't make sense to me at 1st, but some people told me to look at it like that. and kept the rebound loose, so it keeps weight on the tire after the hit, thats when it was spin a few feet out. thats with having you LCA angle to much so it unloads to much after the hit too.

I might be wrong, but I remember being told you know you went to far when to get wheel hop. I never got my car to do it, but only did it a few times on drs. And I had the SA forn strange shocks, the drag race ones, that I believe are set on firm compression. So every time I got the car work with it aggressive... the 2step over 6K on DR (its easier to have the suspension OK 2step 5-5,000 and get 1.5s thats good. cam only you not making a ton of power, and the motor is gona get pulled down a little so you have a bigger window of it working. But to have them not just blow away turned up to 6300-6500 making the more power, and more inertia in the clutch. you had get everything to work right.(1.4s, 1.45 best) It would hit get them planted yank them a bit, and get weight on them, and not unload them thu 1st gear getting the car moving. But the front end would bounce a few times, it looks stupid but it worked. thats why I got better afco DA now but haven't made any passes on dr is a while.

also dont be afraid to add weight to the back. only time I get the car to run 10.6s on DR was adding weight (think 75#s) on the rear end, and the tank full. And 10.8s street mode, driving it to and from was with the tank full, I dont think I had any weights on the car.
Old 08-20-2013, 10:34 AM
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Originally Posted by fly boy_1
Right on, so for the 330' mark what would be considered a good time there? Like you mentioned all I've really read (aside from your posts) are about the 60' coming down but the 330 is rarely mentioned.
Every set-up will be different.

Just concentrate your efforts on making the 330' quickest. That will be a combination of the right amount of wheel speed(the "right" amount will actually have a good bit of tire slip/spin in it but this is what you want to develop wheel speed with a slick) and 1-2 shift and how quick you can bang that next gear.

Now that doesn't mean to ignore the 60' altogether, but it is not the single most important piece of the puzzle. 330' tells it all.

Last edited by Sales@Tick; 08-20-2013 at 10:39 AM.
Old 08-20-2013, 02:15 PM
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Do you happen to have any links to launch videos with the "right amount of spin"? Lots of amazingly informative posts in this thread. Thanks again to everyone who replied this is a tremendous amount of help for the community!
Old 08-20-2013, 02:21 PM
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Originally Posted by studderin
thats with having you LCA angle to much so it unloads to much after the hit too.

I might be wrong, but I remember being told you know you went to far when to get wheel hop. I never got my car to do it, but only did it a few times on drs.

also dont be afraid to add weight to the back. only time I get the car to run 10.6s on DR was adding weight (think 75#s) on the rear end, and the tank full. And 10.8s street mode, driving it to and from was with the tank full, I dont think I had any weights on the car.
That's interesting about the LCA angle, I didnt realize you could have too much anti squat going on? So with too much angle it plants hard and tends to unload? How did you determine what was enough without being too much?

That's another interesting point about weight in the rear, I notice on the street it seems to hook better with my subs in, I'll try leaving them in at the track the next time they are around the weight you mentioned.
Old 08-20-2013, 05:39 PM
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You can hear the tire slipping/spinning/grabbing as it goes past the camera man. This is one of our customers cars we built and tuned. My boss is driving.

Old 08-20-2013, 05:45 PM
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So it looked like the sidewalls wrinkled a lot. Too much is when it wads to the point that it wheel hops correct? Couldn't tell for sure but it also sounded like it spun a tiny bit on the 1-2 shift as well? Thanks for the video that'll be helpful, I'll try to get mine somewhat like that haha.
Old 08-20-2013, 05:46 PM
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Here is another good one of James Short's M6 when it was a nitrous powered 408 with TFS heads:

Just a little too much slip on this one, but you get the picture.
Old 08-20-2013, 05:48 PM
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Originally Posted by fly boy_1
So it looked like the sidewalls wrinkled a lot. Too much is when it wads to the point that it wheel hops correct? Couldn't tell for sure but it also sounded like it spun a tiny bit on the 1-2 shift as well? Thanks for the video that'll be helpful, I'll try to get mine somewhat like that haha.
Yes, that was perfect on the amount of wrinkle that the sidewall had. That's what you want. You do not want it to wad up though correct. We had 12.5psi in the ET Streets on that pass.

It did spin on the 1-2 yes. That's a 3800lb. car with a Iron block 408, AFR 225's, V.1 Polluter cam, Fast 90 and a 175 shot.
Old 08-20-2013, 06:02 PM
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Ok good to know, I'm heading to the track tonight and I'm bringing the go pro so we'll see if I can make any progress. Another question, at what point are rim screws necessary? Mine currently dont use any.
Old 08-20-2013, 06:46 PM
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what tires do you have? I thought you said you have radials?
you NA too? how much power?
Old 08-20-2013, 06:49 PM
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Originally Posted by fly boy_1
They are 18 way adjustable. The car made 412/376 on a dynojet last week, peak hp at about 6500, and peak tq around 47-4800, NA no power adder right now. The LCA's are in the bottom hole on the brackets, MWC fab9 housing with 4.11 gears, torque arm on a relo bracket that comes with it, 2nd hole from the bottom, and pinion angle is currently at about -3*. 300# springs in the front, and stock v8 spring in the rear with the heater hose mod. Only weight reduction is jack and spare removed, along with back seats. Tires are 315/35r17 toyo proxes tq's.

I've got a 2 step and linelock waiting to be installed, didnt determine what rpm might work best on the launch yet. If theres any other info you may need let me know, thanks for posting!

thouse tires are gona suck. is that all you have or you want to get them to work for a class or somthing? those are alot different then slicks
Old 08-20-2013, 07:05 PM
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on M&H DR on the stock 16s, I htink the size is 275/60/16 there about 28" tall so have some sidewall, thats a big help, over your 17s. you can't get any wheel speed/spin they dont recover. I dont think I had a ARB and had used summit 3ways shocks still. you have to ride the clutch a little. id say the clutch was out when you hear the tires cherrpin' about one car length out.
just messing around like most of the time letting off in 4th, then if it close I stay in it. Last pass let the clutch out to fast, thats whats happens on radials, there not gona turn 1-4 turns then hook.They don't want to hook back up after you spin them and get the weight off of them. So you have to catch it before you WOT and they go up in smoke, And wait being light on the gas going between 1/4-1/2 thottal and hop the hook back up before you have to pull 2nd. I got lucky and did it if you listen close before it hooks back up.
Old 08-20-2013, 08:04 PM
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Actually I switched out the dr's for a slick after the first post. Its on a 26.5-10-15 hoosier slick now. Im at the track now and just my my first pass in. Bogged out hard on the launch to a 2.48 60' and 6.071 330. I need the 2 step so I can just floor/dump it. The tree dropped before I was ready so no clue wtf rpm it was haha. All in good fun tho its coming along slowly. Ran a 13.3 at 114.67. I have a video of the pass, it separated good then unloaded on the bog.
Old 08-20-2013, 09:24 PM
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I don't think he realized that. I think he thought I was telling you how to hook a slick while trying to use radials.


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