Front End Rise & Weight Transfer

Discussion in 'The whoa and the sway.' started by Bigpig455, Jul 12, 2012.

  1. Bigpig455

    Bigpig455 Fastest of the slow....

    Bill - thats almost exactly where I'm at now - best 1/8 mile was 9.50 at 73 mph, My average 60 foot is 2.20 even, with an occasional 2.17.

    Gary - I measured my springs - .690! No wonder the front wont budge and it rides like a truck.
     
  2. GS Spoken Here

    GS Spoken Here Well-Known Member

    My 65 has a 3:23 posi and it does have closed lower control arms and a stock sway bar. It is a SP T300 and I brake stall it in high stall to about 2000 and ease it out and gently mash it. I do have a SP control switch to lanch and keep it in high stall but with the stock tires it is a worthless, the tires just go up in smoke. I am planning to get a set of sticky tires this fall and try again to see what I can improve the 60 foot and 1/8 mile times. I am also going to change the intake to one with the "DOC" cut out front to rear. Thanks Bill.
     
  3. tufbuick

    tufbuick RIP

    Here's a combo that I've had on (GrandNasty) 1987 Grand National for years.

    Removed Front Sway Bar.

    90/10 Shocks up Front.

    Backed off Upper and Lower Control Arm Nuts about a Turn.
    Installed Jam Nuts to keep anything from loostening further.

    MT Drag radials out back.

    Car has about 6" of front end travel on launch and stays that way 'till I get off gas

    1:40 60 foot times with stock rear suspention with air bags...leave at about 3800 RPMs

    I drive this car on the street all the time and never had a handling issues....ever!
     
  4. Bigpig455

    Bigpig455 Fastest of the slow....

    Bill - I did the "Doc Mod" on both my AFB and Q-Jet manifolds, it seems to work pretty well, especially with the AFB - I think I found it was good for a tenth, maybe more.

    Tufbuick - Was the front sway bar binding or limiting travel? I put longer links on mine, and it doesnt seem to limit travel anymore, and I greased the frame bushings fairly well so it seems to not bind. 1.40 is phenominal!

    I have heard differing opinions about using 90/10's on the street - I like the compitition engineedring shocks, but not that you have to take them out to adjust them... are there any adjustables with an external adjustment on the market?
    '
    Sticky tires - you'll all think I'm crazy, but I'm not sure the rear or trans are strong enough to take sticky tires - street tires are kind of a "fusable link"...I cant tell you how many times I've heard "I didnt start breaking stuff 'till I put slicks on it". Of course the flip side is no traction. I think I'm gonna see how far REAL weight transfer takes me, and call it good.
     
    Last edited: Jul 15, 2012
  5. Da Torquester.

    Da Torquester. Platinum Level Contributor

    I have used my CE 90/10 shocks on the street for many years with no issues. Of course on the street I use them with a front swaybar and the car handles and drives fine. When I go to the track and pull my swaybar off, there's a world of difference. And driving on the street with it off would not be advised. You can but your car will roll and handle terribly. 90/10 shocks on the street with a swaybar is not a problem, except if you are in to turning and burning. John.
     
  6. Bigpig455

    Bigpig455 Fastest of the slow....

    Thanks John - I pulled the trigger on the CE's - I'll start them on 70/30 and see if that gets me a happy medium.

    You mention you removed your front say bar - Was it binding or limiting travel?
     
  7. flatire

    flatire Well-Known Member

    Hey Rhett- good thread.
    What is the "Doc Mod"?

    I had been fighting traction with drag radials, i put a video camera on the bumper to watch what was going on.
    It was interesting to see all the water running off the tire as i rolled thru the water box.
    i don't know if it was enough to soak the wheel well and then drip onto the tire when staging, maybe.
    I've changed my burn out procedure.
    I also thru 100lbs of weight in the trunk, just to see.
    didn't slow it down, didn't hook any better either.

    Tim
     
  8. Bigpig455

    Bigpig455 Fastest of the slow....

    There is a sticky on the nailhead section on the Doc Mod with pictures, but it basically involves removal of the primary/secondary divider on each side of the carb pad on the intake (see attached) .. it increases intake volume, but Tom has brought up it may decrease intake velocity, at least on the deep side. It did gain me some power, but I'd like to do a trackside comparison. I've got a line on a unmolested Q-Jet intake, I might be able to do that later this year if I can buy it right.

    I turned my quickest ET in on the street with tire, toolbox and full tank, but at the track I run light with about 3/4 of a tank...I did do a comparison there and lost about a 10th on my 60 foot with the weight. mini-IMG_2215.JPG
     
  9. urbancowboy0307

    urbancowboy0307 Silver Level contributor

  10. flatire

    flatire Well-Known Member

    Thanks!
     
  11. Da Torquester.

    Da Torquester. Platinum Level Contributor

    I removed the sway bar at the track and installed it when I was through racing. The main reason I removed it was for maximum weight transfer and front end lift. It helped immensely ! By leaving it on it just kept the car from transferring the weight to the rear tires. I wouldn't recommend driving on the street without it for a lengthy time. For just a trip to the track and back you should be ok, but the car won't handle very well. Just have to take it slow and drive carefully. John.
     
  12. Bigpig455

    Bigpig455 Fastest of the slow....

    it's a 200 mile round trip for me, with some twisty sections - I pretty much need it for that ride...

    I did put longer links on, with about 4 1/2 inches bushing to bushing....maybe that'll give me more front end travel before the whole thing pulls tight....I'm more concerned about the frame bushings binding as the bar rotates. Has anyone ever hogged out the hole in the bushings for "looseness"?
     
  13. Bigpig455

    Bigpig455 Fastest of the slow....

    Ok - all the parts are in, and I'm gonna try to start work this weekend. I'll take pictures of a typical launch before I pull it apart to compare with how it launches after..

    I went with

    Moog 6204 Springs
    Afco 20033 Low Friction lower ball joints
    Comp Eng. C 2610 adjustable drag shocks
    Napa 265-1277 Sway bar links (previously installed)

    I may have to also use AFCO ball joints on the uppers, I'll try it first

    I'll install the shocks at 80/20 to begin with and see how it works from there.
     
  14. Bigpig455

    Bigpig455 Fastest of the slow....

    Started work on it this weekend - didn't break anything!

    The spindle end of the lower control arm was captured by the "dish" of the drum brake backing plate, had to take the plate and everything else apart for clearance.. never had to do that before!

    Also took a "before" shot of a typical launch... thats about 1/2 second in at full throttle, the tires are just starting to haze. the OEM springs make it looked like it's parked! mini-IMG_2984.JPG mini-IMG_2980.JPG
     
  15. R4E5G5L

    R4E5G5L Not a Cutlass

    Update?
     
  16. Bigpig455

    Bigpig455 Fastest of the slow....

    It's all togther, but I'm not quite there yet.

    The 6204 springs didnt give me the ride height I was looking for (I like 'em high!) so I may have to use 1/2 spacers. I will say it rides much better, they're a much more compliant sping. If anything, it sits 1/2 inch higher than before. still about 1-1 1/2 less than I was hoping for.

    I havent taken pictures yet, but from the seat of my pants I'm not getting the lift I'd hoped for - I plan to back off the lower control arm nuts and double nut them and loosen the sway bar links to give some room for the ends to "cock" between the bushings. I also need to check the setttings on the Competion Engineering shocks..you have to select the settings by feel, and what do I know? I thought I had them set to 90/10, I could be wrong...

    Who knows, I might take pictures and see it's doing great and it's all in my head, but it feels so much different than my 71, which just flies up at the slightest throttle - maybe its just the difference between the 2nd and 3rd gen A body cars.......

    I'll keep plugging away, and I have a track rental day coming up on the 7th where I can really play with settings - I'll check back in.
     
  17. Bigpig455

    Bigpig455 Fastest of the slow....

    OK, now we're getting somewhere.

    I backed off and double nutted the lower control arm bolts. Still ,from the drivers seat, it doesnt feel like it lifting much...but if you compare this (hastily shot in an elementary school parking lot swarming with angry dog walkers) photo to the "before" picture, it's like night and day.

    I think that did the trick....
     

    Attached Files:

  18. Bigpig455

    Bigpig455 Fastest of the slow....

    For those who were following this thread - A picture from the track yesterday.It all worked well and the car launched great.
     

    Attached Files:

  19. Gary Bohannon

    Gary Bohannon Well-Known Member

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