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Discussion Starter #1
I've been asking a number of people about this and was wondering what some of you might say about it..

At what point do you quit trying to "dead hook" a doorslammer and try to get it "up on the tire"? When you talk to the pro-mod guys, the things they are trying to accomplish at launch, and getting down track are a lot different it seems than the slower cars. I'm just kinda curious when you stop trying to dead hook one and you start working on tire speed, etc.

Anyone care to go into detail on this subject?
 

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John,

I don't think it's a good idea to dead hook any car. Really, what happens when you dead hook? You essentially 'stop' the entire drivetrains momentum... and now the entire system has to recover from that..... and there is not time for recovery.... that's ET just blowing away in the wind.

The key is to obtain a small amount of spin balanced with momentum out of the gate... When you see folks with incredible 60's based on their combo... that is when they find the perfect balance of wheel spin, versus momentum out of the gate....

Anyhow that's my take on it, and my experience.
 

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Discussion Starter #3
This topic is one that I often find people starting to get real quiet when I bring it up LOL - it is nice to see some people aren't skeered to talk about this stuff.

What do you look at besides the obvious 60/330'et and driveshaft rpm. Do you guys also watch your shock travel/front and rear to try and get a handle on it?

What steps do most people take when trying to deceide what to do - for example Chris - the bumper dragging wheelie in your avatar, what did you guys do after that to get ready for the next pass?
 

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John,

That was a 1 time thing that car will never do that again. I ran first round qualifying, and I must have gotten in some oil, or something because it just spun... so I figured the track was junk and loosed up the front shocks 2 clicks... and that was the result. 2 clicks back to where we always run it, and it was back to 1-2 foot wheel stand.

As for what we monitor, all of the above. We monitor how much the rear of the car rises, how much wheel spin we have, how much it carries the front end out and we make shock judgements based on the timeslip, versus the car data... most of my racing experience is with a small engine so I'm balls to the wall on a launch in terms of power... I'm not holding anything back on a launch. So that scenario, makes some things easier for me, and some things more difficult. To date, I've been 1.22 60', which is pretty good for a n/a small tire car.

Often folks get quiet for 2 reasons. One, is that they are not there yet with their own stuff. Two, is that it took so long to find the proper launch technique that they really don't care to share it...

It takes a lot of testing to figure it all out forsure,.. but I'll say this. There is much more "in the engine" to a launch, than most folks give credit for. It ain't all chassis. It took me a long time to figure that out................
 

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I agree with the no dead hook, My car would always dead hook on launch and the 60's were very poor lost a lot of engine RPM on the launch, The one time it did 60 it best was minor tire spin off the line. Had I realized that dead hook was a bad thing (in my case at least) way back when could have got the car to run a whole lot better Just my .02 :|
 

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Discussion Starter #6
Good info... Have to agree Chris - that 1.22 is very impressive. Interesting point about how much the engine affects launch, I'm sure that's the case on a N/A car more so than a power adder setup.

Just one more question if you don't mind.. How do you guys measure tire slippage?
 

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slip is measured w/ some sort of datalogger in rpm.it is a must for getting the full potential out of your combination.racepak, autometer and edelbrock sell dataloggers (just to name a few)but are a little expensive.autometer also sells a tach with a drive shaft sensor and is downloadable that is reasonably priced.every combination will like a different amount of slip you will find this in testing.chris dead on on all accounts.how much power ,rpm and how fast you ramp the power back in is just as important as your chassis adjustments even on power adder cars, probably more so.
 

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I get accurate data from the driveshaft... You can see the graph climb and come back down when the tires begin hooking up... depending on when the graph starts accelerating, then decelerating, to the point where it begins climbing again is wheel spin.
 

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Gary,

I have no idea what my weight bias is right now. I just keep trying to get my weight down but I can guarantee I'm nowhere near 50 percent in the front.... just can't do it making a car this light... it's a 2810 pound car with me in it and no balast in it.

I'm doing some weight removal right now but it's all in the rear of the car. Can't get anymore out of the front really... carbon brakes? LOL.

I use Strange coil overs in the front. They are single adjustable but I'm selling those and putting double adjustable on it.
 

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2810 w/driver.........Kinda makes me laugh when I see people w/ Camaro's thowin' more power at them when they still weigh 3400-3600lbs.

I've been unsure of a C/O on the frt.,I was under the impression they wouldn't allow the travel to transfer the weight and get the car to hook,But you car seems to be good evidence to encourage me to go that way.
I'm replacing the old dbl adj Koni's that I had in the frt. with dbl. Afco's to match the rears.
I WAS going to retain the Moroso spring but have been trying to decide for sure.
The springs I had in the car were 17lbs for the set,I'm sure the C/O's are lighter.
And on top of all this I can set the ride height easier......

A friend who runs IHRA Top Stock w/ a Buick was telling me when he tried a set of C/O's on his car,Like me,He was skeptical and feared it would not work.Told me the frt suspension barely moved,But at the track the car went for the bumper,So one adjustment and the next pass was 1.26 on a 9'' Radial slick.......This was with the QA1 set-up which he thinks the Afco's are even nicer,Just weren't available when he switched.

My car car was 3430 w/driver and 54% on the frt,It worked well but I never really got agressive in th 60',I kept the "tight" converter in because the car was consistent and I was afraid to change anything.Best 60ft was only 1.31 which I thought was decent until my buddy went in the mid 1.20's w/ his Top Stocker.

Sorry for the rambling........It's winter
With the 100 + lbs I have been removing from car,It will be close to 3300 w/driver,And 52% on the nose,I'm really anxious to move some of what has been removed to the rear and try the car at 51% but I have plenty to do before that
 

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Discussion Starter #16
Gary - don't expect a lot of weight savings from a double adjustable coil over w/springs vs Moroso springs and conventional shock, it's only like 11lbs total savings for both sides and you will probably give up at least a little travel depending on how you set everything up.

The real weight savings comes from using a lower a-arm that utilizes a heim type mount for the coil over vs the traditional spring seat/pocket.

You can figure that the swap from standard a-arms to tubular along with coilovers to save approximately 37lbs.
 

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The key is getting the right arms too.... I had Next Generation Racecars build my arms and they are all 4 around 8-9 pounds, heims and all. Thin wall chome moly. The heims work a lot better than bushings, and are far more adjustable. Lost the stock type ball joint in favor of a nascar type heim ball joint.

11 lbs is 11 lbs.... find 11 lbs in 3 spots and that is 33 lbs. Even finding 2-4 pounds, if you find that 3 or 4 times that all adds up.

Rack and pinion saves a ton of weight... lose the iron steering arms on the spindles... make them out of thin wall chrome moly.

I've not left anything untouched. My car with stock floors, no swiss cheese anything, all glass windows with regulators, all steel except hood and front bumper, stock trunk, stock spindles, etc, and a chassis with tons of bars will weigh 2750 when I'm done this winter. That's not easy with a 69 camaro. At one time my car weighed 3550 with me in it. So I've lost 800 pounds just workin away....
 

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Discussion Starter #18
Speaking of weight, anyone done much research on front tires? I've got the Mickey Street Type front tires and I think I can shed a few lbs switching to the Drag version. However I've been seeing these new ads for the new front tire Toyo has, anyone have an idea what those weigh? Wonder if they really do reduce rolling resistance?
 

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My stock a-arms were 12lbs ea. for the lower and 9lbs ea. for the uppers...42lbstotal.
New tubular uppers w/ heims are 5lbs ea. and lowers are 9lbs ea.....Total is 28lbs.

So if I can remove 11lbs from the shocks and springs that is a total of 25lbs....I'll take that but I'm curious as to how you arrived at 37lbs,That would be better.

And Chris.....
That's what I'm working on,Many people were surprised when I would tell them my car was 3430 w/driver........Guess I should just say 3600lbs and pretend I'm making more power than all the other Buick guys :lol:
 

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Discussion Starter #20
My stock a-arms (Nova) were apparently heavier than yours and my tubular lower arms are lighter (no spring cup).

Stock Arms = 46.4lbs
Tubular Arms = 20lbs
A-arm Savings = 26.4lbs
Shock Savings = 11lbs
 
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