called Koni Shocks the past 2 days, talked to 2 different techs and got the same answere. heres the deal. the front of my car lifts very quickly lifting the front tires a few inches and drops "VERY" fast. drops just a little maybe 2" then rises the 2" and runs out fine frome there. i was thinking the rebound rate on the shocks was wrong. both koni reps said my problem was in the rear set up. the rear of the car does not appear to squat at all. they said the front was tranfering the weight to the rear and it was instanly being passed back to the front. not a front shock issue. Now, my thinking has been the rear wasent supposed to squat. they said put zip ties on the rear shock rods and check for compression. i will do this. how much does the rear need to squat and what do i need to do to get the rear set up properly? they suggested diffrent rear springs, and or possibley lowering the airbag pressure. now at 16R/5L. they also said i maybe over tired and underpowered for the set up as is. do i need rear coil overs to dial this in? rear set up now is ssm bars factory location, metco uppers set a 4* down pinion angle, airbags, 1" rear sway bar. factory rear springs. thanks Dave

What is your average 60' time. Is it pop and drop the front end evertime?

What are the rear shocks set at and what springs are you running in the front and rear, and what is your launch rpm and converter flash.

You want the rear tire to bite the pavement separating from the rear fenderwell. There will be no squat.

The fastest way to rectify this is to video the launch and study it. Is the rear to loose causing excesive tire seperation and forcing the wieght back to the front or is the car hitting the rear tires to hard and spinning?

the best 60' to date is a 1.57. last outing was 1.58-1.59. yes its pop and drop everytime. we put a white strip on the rear tire and it shows to be rolling out (not spinning) for the first 10' or so. this is about the time the front tires come back down and the front drops about 2" and then comes back up. at this point rear wheel speed is a little fast to check for spinning but i have a play back tach on the way so maybe this will indicaate tires unloading. the front springs are moog 6 cylinder springs with ce 3 was set at 60/40. at 70/30 it was worse. the rear socks are ce 3 way set at 50/50. the launch rpm is 1500 and when we put a video in the car it looks like the 8" ati converter is flashing just a little over 4000 rpm. the playback tach will help here as well.

I tend to agree with what Koni was telling you. Now, if the front end was rising and falling without ever lifting the tires I would tell you that you needed travel limiters and/or stiff rebound on the front shocks. However, once the front tires are off the ground it's entirely up to the rear suspension and power plant to keep them there. Focus your efforts on the rear suspension. The advice given by 1bad67 is right on the money. It was only through frame by frame replay of my launchs that I was able to go from 1.6x to 1.4x 60' times.

The way you explain it sounds like the front is releasing all the stored energy to quick, evident by it getting worse at the 70/30 setting.

At 70/30 you should have noticed a difference if the rear extension was pushing the wieght back to the nose, because at 70/30 the compression is stiffer, therefore you would have eneded up at the 90/10 setting as a crutch to keep the front end up and wieght on the rear tires.

What you do say is 70/30 makes it worse. 70/30 has stiffer compression while softening extension(rebound), leading me to believe the front end extends to fast at 60/40 and even faster at 70/30 transfering wieght to soon. The rear does'nt have any leverage yet to hold the wieght.

My two cents, try a stiffer adjustable shock such as the koni SPA-1, regular koni( or any stiff shock), and ultimatly install a spring with more stored energy instead of the 6 cylnder spring. Also the air bag is changing corner wieght. Have you tried it without any PSI on the bag? With a small block and ssm's adjustable uppers you should preload the bar if it twists.

believe me.. you need to video the car because what your help see's, remembers, and explains is totally different than what happen. Can you remember 1.6 seconds of action and explain it 1-2 min. later in framed detail garuntee you will mis something.

Originally posted by 1bad67:
because at 70/30 the compression is stiffer, therefore you would have eneded up at the 90/10 setting as a crutch to keep the front end up and wieght on the rear tires.

What you do say is 70/30 makes it worse. 70/30 has stiffer compression while softening extension(rebound), leading me to believe the front end extends to fast at 60/40 and even faster at 70/30 transfering wieght to soon. The rear daosn't have any leverage yet to hold the wieght.
are you sure you dont have this backwards?

this was taken from competition engineering's website

Competition Engineering's Front Drag Shocks are adjustable in three ratios: 90/10, 80/20 and 60/40. These ratios reflect the percentage of force required to extend and compress the shock absorber, with the first number being extension and the second number compression according to CE the second number is compression, which might (*edit*) explain why the 60/40 setting works better than the 70/30, more compression resistance keeping the front end up longer.

Go to there Q&A and read that WTF? Can you explain it? it sure is confusing me. All I know is I have tried a pair of them and 90/10 or 10/90 (whatever) are soft extension stiff compression. meaning very little force to extend, and 9times the force to compress.

Either way 60/40 is darn near equal on extension and compression, and the set of CE's I have from 60/40 the extension becomes softer and compression(shortening the shock) becomes stiffer.

Maybe I have the terms backwards? I do know sheetmetals car is worse with softer extension if his 60/40 means almost equal force required to extend and shorten the shock.

Go to there Q&A and read that WTF? Can you explain it? it sure is confusing me i agree it is confusing, but remember i was asking not telling.

the way i always understood 90/10 shock is exactly as you state, soft extension stiff compression. but according to CE's website its completely the opposite, maybe they have it backwards????

Either way 60/40 is darn near equal on extension and compression, and the set of CE's I have from 60/40 the extension becomes softer and compression(shortening the shock) becomes stiffer.ignoring what it says on CE's website, if the 10 in 90/10 represents extension how can a 60/40 shock have softer extension than a 90/10?

on the same token if the 90 in 90/10 represents compression how can a 60/40 shock have stiffer compression than a 90/10?

the only way i see a 60/40 shock could have stiffer compression and softer extension than a 90/10 is if the 90 in 90/10 represents extension and the 10 represents compression, like CE's website states.

that is unless there is something i am missing, if i am off base here please someone, anyone set me straight. it sure would be nice if the makers of these shocks provided more info on what the settings mean and do and how to use them, unfortunately that isnt the case.

i also want to appologize for sidetracking this post which wasnt my intent.

What I was explaining that if the first number is compression, and the second is extension, the car works better with more force required to extend the shock, 40 versus 30. If the rear was pushing the weight back to the front the 70 should have helped more than the 60 compression setting. 70 requires more force to compress the shock than 60. Basically it has two problems the one koni identified, and second its moving all the wieght to the rear tires to fast.

Koni's diagnoses is not wrong its just I think there sending sheetmetal in the wrong direction. My two cents; the car needs a better and a stiffer front shock, and ultimatly the right springs. Moving to the rear settings is the wrong place to start. IMO. video would be nice!

thank you, evidently CE's website must be wrong. i checked around and according to lakewood and koni they are. out of all 3, koni had the best website by far, from the description of the parts to tuning them.

http://www.koni-na.com/pdfcatalogs/KONIMotosportCatalog.pdf

The Koni SPA1 series shock absorber (for drag racing only) is a complete departure from the old "90/10" thinking which is no longer effective in modern drag racing.

the old thinking was to allow the vehicles front end to rise quickly and stay there to promote as much weight transfer as possible to the rear wheels. this was achieved by no rebound forces ("10") and a great deal of bump forces ("90") this massive amount of bump force was supposed to hold the front suspension up to maintain that "bite"

unfortunately that nose in the air position trapped huge volumes of air which ruined any attempt at aerodynamics so E.T.s were not as good as they could have been.

Koni SPA1 shocks deal with this in several ways. first they use no bump (compression) damping. why? to allow the front end to settle quicker restoring the nose down attitude that is so essential for cleaner air flow. second the rebound (extension) forces are velocity sensitive: that is they increase at a rate directly proportional to piston speed. im kind of concerned about the part where they use no compression resistance. with no bump resistance dont you think after the initial weight transfer a nose heavy car would settle too fast causing the rear tires to unload? especially if it doesnt have the power to carry the front end (not just pulling the wheels up for a brief moment), then combine the fact that the rear suspension is seperating pushing the front end down.

i also wonder if the other makers, lakewood and CE have adopted this method?

and i do agree about the stiffer front shocks, and as far as koni saying that the rear needs to squat, with components like ssm bars and no hops that incorporate "anti-squat", that is contrary to what we know to be true.

what would be nice is a good double adjustable front shock, which would allow you to tailor the extension and compression seperately to your needs. its too bad that there isnt an affordable double adjustable shock out there.

if because of cost a double adjustable shock isnt an option, i think a stock type gas shock would work better up front than any of the 90/10 to 60/40 drag shocks (in a nose heavy chevelle at least). and would be one step better with Tom aka mc71454's front "shock nut trick".

we have almost every pass on video, thats how i was able to spot this. i have a et of good KYB gas shocks i may try. also Koni said a 50/50 shock that required, lets say, 50lbs force to extend would also require 50lbs compression to be a 50/50 shock AND a shock that required 25 lbs to compress and 25 lbs to extend was also a 50/50 shock. now neither of these 2 shocks will work the same. my thinking was using a shock with a higher compression rate would fix the problem, thats why i set the shocks to the stiffest rebound rate. at anyrate, i hope to get it figured out without having to spend a fortune. Dave

Hey tin man,

Buy the way, how fastdo you want to go? Go buyeither the Dick Miller book for around $15.00 to your door, or get serious and buy Dave Morgans Doorslammers soft book. He is indepth but read it 30 times or so and you will hook like a pro stocker, trust me, the more you know about this highly gray area,( and it is still gray for most pros) the more power you will have, knowledge my man, for every action, reaction occurs and a anti-roll drag race sway bar is the hit from pro mod down to my 72 elky.
I got it right the first time and now both front skinneys come off the ground and the back of the bed is darn near level every launch as recorded from video.

Also, don't mean to step on toes here but every car has to squat, even front wheel drive car squat the rear end, watch em some time. If the car/truck does not squat, your vehicle would be called the Hasbro sit & spin toy, it has to squat, you just can't see it unless video taped & played @ slow speed.

I have 90/10 Comp. Eng. 3 ways in the front & QA1 12 ways in the back and you got to get the front end up quickly, the term porpusing sound familiar to you, its when a car goes up & down in the front end, know why, too tight ofa shock setting in the rear.
See, you need to raise the front first to send the weight to the back, the body will drop, trust me, then like mentioned before action/reaction, the body should go up right after you hit the loud peddel, with the correct rear shock setting and a anti roll drag bar setup, this will accept the squat, then right away begin to fight it forcing the axle down and body up to maintain a certain attitude until after the first few feet, than the rest of your settings takre over. I've been here 3 times, but try for yourself to gain your own conclusion. But if my 3650# elky can yank the fronts, so can everybody elses, you just need sone torqueand lots of knowledge on the suspension systems.
Hope this helps and doesn" hurt anybodys feelings, these are what I have gone thru & it has worked flawlessly for me and Dick Miller knows it too.

Enjoy.
John G.
O/C 9900
"The Elkymann"

You'll find Koni shocks under a host of stock eliminator cars.

I can assure you I have gone to great lengths to not have any Squat in my launches and I do not have any now.

My KYB Gas front shocks are very stiff on the rebound when compared the CE 3-ways

My front rises instantly and very easily...BUT as the front is rising, immediately the rear begins to separate. This is what you have correctly stated you are striving for.

Dave, I had much better luck with standard Gas shocks in the rear than those CE's, but nothing beats the QA1's for rides like ours. I tried the CEs twice and always went back to the KYB's in the rear until I purchased the QA1's

I would seriously try your KYB's and try the shock nut deal. Can't hurt to try. I have tried SSM bars and the rear Did separate so it seems you are on the right track

I am now using the Dick Miller No-hops. They and the SSM's generally achieve the same effect.

I agree with Ken, that both the front and rear need to be in sync to work together. I also use Moog 6 cylinder front springs if that helps you any.

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