Need 60' and need help

[Gus68]

Hey guys!!1 Just joined recently, Love the site!!! I heve been fighting some problems this summe and am making myself confused. First off, my car is a 68 chevelle with a 406, th350 with 4500 converter, and 12bolt with 3.73s. This was my first year with the auto, I have ran numerous 4 speeds since I have owned the car, (1993). The last 4 speed was a Ford top loader with liberty pro shifted gears. My best pass EVER was 4 years ago with the 406 fresh, was a 11.997 at 112.9. other wise when it wasnt breaking it ran 12.20sat about 110-111mph, BUT my best 60fts were 1.77 and 1.79s. So I went with the th350 insearch of better 60fts and less breakage. Now my best time is 12.57 at 105, with consistant 12.65-66s but with a better 60ft of 1.73 and .74s. Now Im confused... My 60fts are better (not the best though) but my time and mph is down. I guess the mph could be down cause of the auto compared to the direct drive of the 4 speed in 4th. another thing I am wondering about is my suspension and 60ft. Friends have told me that my car doesnt really do anything when it leaves, they say it looks like I am just leaving a stop sign kinda quick. Any suggestions??? Thanks guys.

[sc racing]

What do you have for springs,shocks,control arms,etc? Where is your pinion angle set at?The th350 has a 2.54 1st gear what were the 4 speeds ratios?Need more info, Im sure somebody here can help you.

[Gus68]

OK, here's my stuff....My front suspension has moroso trick springs, lakewood 90/10 shocks, and I have compleatly rebuilt the front (bushings, tierods bla bla bla) and aligned it myself. the rear is a 12 bolt with 3.73s (I might go with 4.33s this winter). the control arms are stock that I boxed and added poly bushings, I have older lakewood no hop bars with solid bushings. (just a tube in a hole) the springs are also trick springs, according to moroso the right is stiffer than the left, the shocks are 60/10 afco circle track shocks that I borrowed from a friend just to try, (didn't really se much of a difference) I had cheap NAPA replacement shocks. I have an airbag in the right rear that I have yet to air up. The slicks are M/T 28X10.5 on 8" ralleys screwed down. Since I have been reading this web site I have checked my pinion angle, I am embarresed to say I have never checked it before, it is a -2*, meaning it is pointed UP! I thought this is was strange cause wouldn't the higher upper mount of the hop bars cause the pinion to point down??? My old toploader had a 2.78 1st, 1.93 2nd, 1.36 3rd, and 1 to 1 4th. I used to dump the clutch at 5500 to 6200 depending on the day and stuff. Now with the auto it is a whole different animal, I foot brake it with the 4500 stall, the brakes will only hold it up to about 2000. With the 4speed it was violent as hell it would lift the left front about a foot and the right on a few inches and head to the right, I then filled the airbag to straighten it out, BUT my 60ft times were best of 1.77. Now with the auto it is tame but has a 60ft of 1.73, which I think could be improved, BUT the rest of the run is slower.

[Gus68]

Sorry, I ment to say the rear shocks are 60/40s.

[sc racing]

Moving the upper arm up at the rear doest change your pinion angle it just moves your I/C back in the car.You need some adjustable uppers ,when you shorten them it will point the pinion down getting your p/a correct.What is your shift point and what rpm do you come across at?

[Gus68]

I know that lengthening or shortening the uppers changes P A, But if I raise the uppers, as they travel through there arc the upper mounts have to move forward to reach them. I hope I explained that right, sometimes I confuse my self . Anyway, I am woking on getting adjustable uppers. what should I set my P A at for starters??? I shift at 6200.

[sc racing]

With your 3.73 your probably coming over the line at around 5400 rpm you definitly need more gear.I think those no hop bars compensate for the raised height so nothing changes. I think 3* for a coil spring car.

[sc racing]

Hey Gus68 check out the photo in the post " a body trailing arms" in this section, you need to get yours like that

[JeffMcKC]

Hey gus, Does it spin? If it does, you put all those nice new bushings in the front without any spring you had t push the a-arms up and down right? Thats a bad thing, and if you tightened them while it was up they tend to try to hold it there. First thing I would do is to add ny-locks to the front and back them off from tight it, just touching, same in the back. Keep your eye on these even with ny-locks. You really dont need those arm relocators on the back. put a double adj. shock on the back make it extend easy and tighten the contraction when it starts to shake.

4500 with no spray and a small block with that gear is not enough for killer 60's 2000 climbing to 4500 if it gets there can take a lot of time

Good luck

[Bob West]

I still have rubber bushings in the front control arms with the serrations ground off the uppers and loosened top and bottom as someone mentioned above. No front swaybar, MOOG springs, KONI street adjustables set on full soft. I am running a Moser 12 bolt that has the lower CA mount about a 1/2" lower than a stock 12 bolt and the ears are raised about 1.5" above a stock 12 bolt, adjustable uppers set at stock length, boxed SSM lower control arms and the pinion angle is probably 2-3* down, although its never been checked, just going by visual appearance. I am also running a HRpartsnstuff.com bolt-on antiroll bar in the back with QA1 single adjustable shocks set on 8-9 clicks of which 12 is full stiff. The front end has to be loose but not too loose as to let the rear tires unload. My car will leave with the front tires about 6-12" in the air (depending on weather conditions) and carry them for a car length or so, set them down and go.

[Gus68]

yes the car crosses at about 5500. When I did the front I made sure to tighten the control arm bushings at ride hight. I am thinking about grinding the teeth off the bushings and loosening the bolts like Bob said. I too, removed my front sway bar years ago, forgot to mension that. How does the car act on the street with the front end loosed up? And no my car does not spin. I used to dump the clutch at 6000 and break stuff . I used to spin the slick on the rim till I screwd them down. which brings me to something a freind and I were discussing. If your tires dont spin, is it possible to improve 60ft times with ONLY suspension mods??

[Bob West]

I dont even have my slicks screwed to the rims, yes they do move, very slightly. Maybe you need a bit more converter or a bit more power. You must have some power if you used to break parts. My car drives fine on the street, the antiroll bar in the rear keeps the car level like the front swaybar used to. I dont get it out on the interstate much any more with the bigger solid roller in it, usually just putt around town. I hate to change between street tires and slicks too, especially during racing season since I run weekly for points in no/e.

[sc racing]

It will ABSOLUTELY 60' better with just suspension upgrades.Horsepower is only a little piece of the puzzle.Take a look at some guys who run stockers like 67-69 Camaros,Mustangs,Novas they have to tune their stuff with stock parts and they 60' better than some 4 link and ladder bar cars.

[JeffMcKC]

If the tires are not spinig you wont gain tons with susp., you are "hooked" already its time to add power, with gear and converter play with the timing and such if your in between checks, Remember HP is miles per hour, not 60 foots, more hp may spin and slow it down in 60 feet but it would be going in the right tuning direction

[Dave Morgan]

Gus,
I'm just a dumb shock and spring guy but I think your converter's too loose. If you can ever borrow a replay-tach, do so, especially if it records driveshaft rpm... here's an idea... What's your trap rpm again? What's your mph? Rear gear ratio? Rear tire diameter? Could your converter be slipping at the top end?
The bushing advice you got was good and you seem to have a handle on that. In fact, your suspsneion situation seems under control. The guy who pointed out that no-spin is good from the suspension package was right, so there's not much more you can do other than "thump it" harder (or smarter.)
Anyway, maybe it's time to ponder the converter and talk to someone like Neal Chance.
Stay Tuned,
Dave Morgan