AChotrod

iTrader: (17)

Well I took the car out last week and only got one full pass in. This is leaving at 5k you guys think the front end comes up to fast and unloads the tires? That was 14psi cold and after I lowered it more the car would bog bad and practically bounce the rim off the ground so Im going back to a dr with stiffer side walls. Car has comp rear shocks at 50/50 and front Strange DAs all the way loose on extension and stiff on compression.
What do you think?
http://www.youtube.com/watch?v=nf6MZWRiwhU

BlackScreaminMachine

iTrader: (17)

One thing I see is you need better rear shocks. At least a Single Adj. QA1 but others will recommended something in a D/A, and probably Afco (optinum).

AChotrod

iTrader: (17)

What makes you say it needs better shocks?
The car has comp 3ways, LCAs, LCA relocation brackets(lca's mounted in bottom holes), PHB, TA, TA is mounted off the trans -2 PA and in the 2nd to lowest hole in the trans/TA relocation bracket. New rear shocks are on the to do list but I had heard lots of good things about the comps so I figured Id give them a try.

z28rob18

iTrader: (7)

wat were the numbers from the full pass?

AChotrod

iTrader: (17)

It was a 11.85 at 117 on a 1.74 60ft. The end of the vid was all messed up from some super loud car

BlackScreaminMachine

iTrader: (17)

When you need to dial in the suspension, M6 cars behave differently then Automatic cars. They definitly need to help control the body which I have had a issue with in the past. The car xfer's weight so well that the body was smacking down on the bump stops among other things.

In some situations Adj stocks are staggard one click from the other and with a 3 way, its WAY too much of a spread.

The way I look at it and it may be wrong is that lets say for stiff its a #3 and full loose is #1, well #2 is the compromise but to have one full stiff and the other neutral may open up a can of worms. But you put in a 12 way Stocker Star from QA1 at least if you need a 7 or #8 click, you can get that inbetween setting and then you can stagger it.

Now I do not own DA shocks so I am no expert and I know madman makes specific valving based on race weight so thats another example of something you can take advantage of.

Like said, thats my suggestion and let us know what works out.

Carter01

iTrader: (11)

FC6 FE1 RC5 RE2 These were the numbers I used when I had the 6sp. Best 60ft was 1.63. I also suggest raising the nose of the car up about 1/2, it will help get the weight back over the rear tires quicker. This worked with the stick but with the auto I had to lower it back down. As BlackScreaminMachine said earlier about the differences between auto and stick cars is huge.

edit - strange DA f/r with 300lb coilovers up front

AChotrod

iTrader: (17)

BlackScreaminMachine I was just wondering if you saw something specifically in the vid that made you say change them.(which I will do over the winter regardless)

I have the strange DAs with 300# springs up front so Ill try that setting. What really sucks is the car used to go in the 1.6s and 11.60s with stock shocks and springs .
My new 275/60-15 MT DRs came in today so Im gonna get those on and mess with the front shocks some more, and see what happens this friday at the track. Oh I forgot to mention I also have a UMI drag bar on the car. In case you wondering why I bought DRs. I want a stiffer sidewall, something more streetable and a tire that doesnt expand on the big end since the 28" QTPs were growing enough to rub the rocker plus I have a built Th350 going in the car this winter.

BlackScreaminMachine

iTrader: (17)

Well this should solve many issues in which this post was about. I can see where the build is going better. Unfortunately no You tube at work but I can look at it when I get home.

DTB_LS1

iTrader: (2)

Are you just dumping the clutch or letting it out a little to preload the suspension? I've talked with several m6 guys on the forum about using this method and actually used it last time out and it worked well. I stage shallow so I don't redlight then let the clutch out till I feel it grab and when the last yellow drops I hit the gas to activate the 2-step and let the clutch out quickly. Using this method helps keep the car from hitting the tires too hard and unloading the suspension. FWIW I've got Strange DAs up front set at 0 Ext/4-5 Comp and SAs in the rear set at 5 and cut a 1.51. I'm still new to this and need some seat time but it seems to work so far and I know I'll be in the 1.4s soon.

AChotrod

iTrader: (17)

I keep the clutch in just enough that the car stays in place and loads the suspension then quickly slip the clutch but its a street twin so when it grabs it grabs hard.

Bitemark46

I saw a few things that came to my concern.

What size tires? Looked like 28's. Drop that psi. If it bogs come out higher. You're blowing the tires right off the hit. A sign of too much tire pressure.

The rear remained neutral on the hit (thats good). I think your shock settings are fine.

300 springs upfront... sorry not a GM suspension guy but is that stock or softer? If softer, by how much? It the vid it seems to run out of travel pretty quick..either by strut travel or springs ran out of energy (aka too stiff).

Are the front struts on full loose? How many inches of usable travel do you have?

If you raise the car you are effectively moving weight rearward but on the downside you are reducing your strut travel. So its balancing act that requires testing.

Whats the track prep like?

-Mark

EDIT: Watch your burnout when you roll out of it. The nose "should" come up and carry a little but it just falls. I'd say the issue is in the front.

AChotrod

iTrader: (17)

28" hoosier QTPs, Fronts are full loose on extension and full tight on compression, track prep was good, tire pressure was 14 then dropped to 12 but it hooked so good the car would fall on its face and shock the tire so hard the rim would almost bounce off the ground. 300lb springs should be about right for my car and weight.

Jon@BruteSpeed

iTrader: (3)

Hooked hard and fell on its face?? You don't have an aluminum flywheel do you? My brother tried that in his LS car....for only one night..and went back to a steel flywheel. If it hooked at 12 psi, raise it in 1/2 lb increments until it is happy. M6 cars typically like a stiffer sidewall so you are heading in the right direction there.

Bitemark46

Explain that to me. If it hooked so hard and it fell on its face then you're coming out too low. Raise your launch rpms. If after the initial hit its unloading then its due to the front stopped rising or you need to stiffen up your shocks on extension to hold the hit.

But arent QTP's equivalent to MT ET Streets? They have a harder compound and sidewall. Ever tried an all out slick? I run my lil 26" ET Drags at 10psi so you can go lower with a 28" tire. From my findings a manual car always does better with a slick and an auto works better with a DR. Manual's just hit the tire way too hard.

The 300lb springs. Is that more along the lines of a stiff drag spring or more of a softer drag spring?

Jon@BruteSpeed

iTrader: (3)

Med drag spring. We have had good success with them.

AChotrod

iTrader: (17)

Jon Its got a Mcleod steel flywheel and a Street twin clutch. Its about as heavy of a clutch flywheel set up you can get so thats not it.

Bitmark The car is hitting the tire so hard its collapsing, distorting something ugly, and almost bottoming the rim on the ground. Coming out at a higher RPM would have shocked the tires even harder. The new DRs are getting mounted right now, I think if I can get them to work the stiffer side wall will help. Also the QTPs would grow so much they would rub the rocker prob from distorting so bad. Shouldnt have that issue with the drag radial. Ive seen M6 cars go wheels up with a very similar suspension and DRs so I know it can work.

Jon@BruteSpeed

iTrader: (3)

I have the same Drag Radials you are mounting on my Formula right now. I think you will like them.

Tally TransAm

iTrader: (17)

your gonna have issues with the drag radials and the 6 speed. its like voodoo magic getting those two to work together

i agree with what bitemark said. from watching the vid you are spinning right off the bat. i would go with definitely suggest a full slick, but with what your working with more rpm and a little less tire pressure, especially if it is hooking then bogging.

AChotrod

iTrader: (17)

I want more of a street tire so I went with the DR. I had them b4 and did just as well as the 28" QTPs are . My best 60s were with a 27"QTP and stock suspension. I guess if I were to change .5 psi until the tires would rotate once or twice it would be a lot better but they still rubbed and arent the best for cruising around. At 12 psi they hooked then bogged and it did not look pretty. Ill see If I can get a vid.
I still think the front is acting weird and need to slow up the extension. Seems like it goes up then slams back down instead of falling back down.