Hey guys...new here and certainly glad I found some information about chevelles here...

My dad owns a 67 chevelle 100% original...gotta see to believe, but we took the original 396 motor out, along with the 4 speed and put in a Merlin 509 and 700R4....for drag racin...He is getting some decent times,11.3@119 with the setup...but his 60' times SUCK! And this is my question...

What the heck do you guys do to get these things to hook. Remember its a full weight car,,,in great condition, and like myself with my car, he want to keep it as original "lookin" as possible..What I mean by that is no plexiglass windows etc.

Here is what he has done in the nutshell. QA1 shocks on all corners (12 way adj), adjustable 4 link in rear...professionally setup with proper pinion angle, 3500 stall converter(could be bigger) but its only going to make the spinning worse. 3.55 gears...need to be higher like 3.08s...

What are your thoughts fellas? He has a chromoly 6 point bar in the car, which helped a little. But he still only after installing all these items able to get a 1.65 60 foot time...

We are no strangers to getting good traction out of cars, but this has even us baffled. I have my vette pulling 1.4s with stock components, full weight car complete even with AC. But this chevelle of his is a bear to figure out. Surely there have to be a few here that have it all figured out.

My thoughts are to lighten up the front springs as much as possible.....

He has also removed the obvious front sway bar, 28" ET M/T slicks, skinnies on the front...the car has no problem pulling the front off the ground, but it just spins like a MOFO through all of first. We have tried about ever burnout technique known to man...still 1.6X 60's..

Can anyone shed some light? Thanks a million!

welcome to T/C. although my 67 is not ready for the track yet, there are some of the most knowledgable and helpfull guys in the world. here. im sure they will point you in the right direction. ALSO, at the top of this page there is a search function that will allow you to look up old posts regarding traction issues. good luck Dave

Thanks man! I will do a search and see what it turns up!

I'll take a stab at it since I race my 66' and have some of the same components you've mentioned. My Chevelle is all steel, only things I've done to take some weight out is radio and heater delete, replaced the driver's side factory bucket with a poly race seat from Summit, and replaced all factory rally wheels with Weld Draglites. The race weight of my car is now just under 3,700lbs (3,680 with me and 5 gallons of fuel). The weight distribution of my car is currently 57/43 (1,975 front and 1,485 rear without me in the car (200lbs)).

For suspension I have the following:

- Global West upper and lower front control arms with Del-A-Lum bushings. I have the bottom control arms double nutted with zero preload.
- QA1 coil-over conversion with small block springs. The front of the car sits exactly 2" lower than the rear.
- QA1 12-way shocks front set on 1st click. QA1 12-way shocks rear set on 3 both sides.
- Front sway bar removed
- Hotchkis adjustable upper control arms, Hotchkis lower control arms and Hotchkis triangulation braces in the rear
- I have about -4 degrees pinion angle
- PST 1.125" rear sway bar
- Air lift air bags (17lbs right, 8lbs left)
- 28" Hoosier skinnies up front and 28x10.5 MT ET Drag "S" series (stiff sidewall) bias ply slicks rear.
- 40 psi front and 15.5 psi rear

I've got a solid roller 460, TH-400 w/8" ATI converter and 4.11 gears. I usually leave just off idle, I've found that my car hooks better if I flash the converter (5,300rpms). My 60' times lately have been in the 1.53-1.57 range. I expect to get them down to the high 1.4x range with some additional chassis tuning.

Let me know if you have any specific questions.

Kjett...

Thanks for the information. We do not put any air in the rear bags,,,what do you think of that? The car has ZERO weight tranfer to it when we watch the videos. Compared to my car, you can see in my sig, which has videos etc. Mine almost transfers too much, if there is such a thing. lol.

With Dads its almost seems like the car is a board. Yet it twists and pulls the drivers side up in the air, but the rear DOESN'T squat like you would think it should.

I will pass this information onto him. Thanks. keep the suggestions coming. graemlins/beers.gif

borrow some other tires to try? is the four link setup complete aftermaket design or is it basically the stock style triangulated design with adjustable control arms? If the front tires are off the ground then you're definately getting weight to the rear. four degrees of negative pinion angle should definately be putting downforce on the tires. I definately wouldn't go to 3.08 gears-you'd never use up 3rd gear. I would think 4.10's would be optimum. Anybody else? ttt

Ski, I'm not sure how it is possible to pull the front end off the ground and not have weight transfer. Perhaps you think the lack of rear end squat means no weight transfer is happening. On a coil spring car it is actually desireable to have the geometry set up to "push" the differential away from the chassis (refered to as body separation).

I do believe that I have never before seen a massively torquey 509 BBC combined with a 700R4 for drag racing. It may only be part of the issue, but I think the 3.07 first gear of the 700R4 may be hurting you. It is quite possible that you are getting too much torque multiplication through the trans and you simply end up overpowering your tire of choice.

Also, your suspension may be unloading the rear tires after the initial bite (as you say it just burns the tires through first gear). Whose 4 link setup is on the car? Some of the chassis companies have technical information on how to properly set it up - perhaps you need to make it hit softer on launch.

If on launch your front end goes up too quickly and then comes down too quickly that can also make for wheels up but tire burning launches. Maybe a slower rate of front end rise would be helpful (different shock settings). Might not be a bad idea to see what you could do to allow for more wheel travel before it hits the bump stops. A lot of guys change out the front suspension bump stops and grind away at parts of their suspension. The idea is that upon launch that when the suspension reaches the end of its travel (before lifting the wheels off the ground) that the sudden stop of wheel travel can jerk the front end down too quickly.

What kind of posi do you have? Are you sure that BOTH tires are spinning after the wheels up launch? I've seen guys with worn out of clearance posi's spin one tire more than the other - and they think both are spinning equally. If the posi is worn it can give the illusion of poor traction because of the weay that it allows one wheel to be overpowered and spin excessively.

...on another note, I need to talk to you about how your Vette 60's in the 1.4x's.

Thomas

Guys, thanks for the comments...

Thomas,

I personally think that 3.07 with our first gear is about optimum for good launches, since the first gear in the tranny is 3.06 This give ~9.46 total gear ratio....speaking with MANY other sucessful dragers, this 9:1 ratio seems to work best.

As for my vette, I can't imagine running any more gear in that thing. It would completely just blow the tires off it. I suspect that dad and I are putting out nearly identical power. Mine made 437.5rwHP and 536rw ft-lbs...which is about what his should be after drivetrain losses.

I think with a turbo 400 or something of that nature, he would be as you said perfect with like 4.10s to maintain that ~9:1 ratio.

He is leaning towards a 350 or 400 this winter, but I really would like to solve this mystery...

Also I bought him a spool that just came in last night. I need measurements off it, for a project I am doing and then I am going to give it to him. The rear differential was just installed and rebuilt back in June/july. We went from rediculous 4.56 gear, where the car was even worse hookin to 3.55s...I think the 10.8 gear ratio, is the cause of the problem.

The 4 link is an aftermarket setup. Still in the stock configuration. When the bar was getting installed in the car, by Neverlift in NJ, who is a VERY reputable suspension guru, with his 1/2 back cars on the East Coast...he set it up for what he said should be optimum settings in a car like that. I have to almost believe him, since he not only has a newer turbo camaro, with 10"slicks crankin off consistant 7sec passes! Along with several other guys that seeked his services.

Anyways, yeah the front seems to twist up on the drivers side, when pop back down quickly. We will have the car up an a lift tonight/tomorrow getting it ready for the strip this weekend. Il will see what I can see in the way of how the front hangs with respect to the stops.

I think suspension stuff is the hardest to figure out. It really is tough. Especially when you have to travel 3+ hours to the track every weekend. Only get a few passes, usually 3, then back to the drawing boards.

If you can think of anything else please post it. Good bunch of guys here it seems!

Whatcha need to know about the vette? Lots picture of it in the website that is on my signiture. Just about step by step pictures of the motor going together etc.

Thanks again!

Skier, use the search function in the Performance forum, for some good info.