Dude, you need to learn a lot more about suspensions... The actuality is that ladder bars are harsher to drive on the street than a 4-link...
-Jeb

 

This is a MAJOR MAJOR undertaking that needs to be done RIGHT, or you will be getting taken to the undertakers.

Remember this is what is holding the entire rear of your car in and under the car. Most of the MAJOR wrecks you see on the strip are caused by something letting loose and causing the driver to loose control.

I would NEVER think about doing this to my car, unless it was in the hands of a VERY skilled individual. 120+ MPH and having the rear **** sideways is not a good thought. Or worse yet on the street coming around the corning into oncoming traffic.

Please use caution and make sure your doing it all RIGHT. Would hate to see something nasty happen.

 

why a 9 inch?

 

I would have thought the same thing... TPI 421 Vette (I think that was his forum name) has pics of his 9" install and it was recent, maybe last week. There is a ton of work involved in this so do your research before you go hacking the car up.

 

I always read that a ladder bar suspension was better for the street because it allows articulation (vertically) of the suspension independently.

A four link resists independent movement (vertical) of the wheels. Both wheels want to move up and down together in other words.

If I think about the geometry and forces involved in both, I certainly need an explanation of why a four link is better for the street.

Rarely do I ever see a street driven car with a four link unless it's driven really infrequently.

EDIT... doing some reading after posting this it does seem most chassis manufactures say a four link is better for the street. I still can't see why though? Enlighten me.

 

Sorry to double post but this reminds me of a friend that had a rear installed by a professional shop. Ford 9 inch four link, drag car only. He was pulling low 10's in a 77 Monte Carlo big block, one of the welds broke about half track, sent one of the links through the slick, barrel rolled the car ten times. Not good, get a professional to do your welds at least!

 

Weird, who told you that?

Both are a live axle design.

 

Actually I'm going to stop thinking about it because it's making my brain hurt.

 

I was looking into this casually last year.
After talking about it with some local race car smart people, they advised against it money wise, time wise, saftey wise, etc.
One suggestion was to just buy a tube frame drag car a slap a vette body on it. Easier, safer and costs only a little more.
The other was to look in the back on National dragster for a backhalfed vette around the year/model I want in the for sale section.
after a few months bingo! an '88 vette back-halfed a certified to to 7.5 sec's. The sale price was cheaper than doing it to my car from scratch!
Just drop a motor in it - came with trans.
I never bought it. But I know what to do in the future should that urge come again.
Mt two cents.

Matt383

 

I wish I could explain this in a more technical and 'cool' way, but both set ups allow the rear to move vertically in a hard launch situation. The 4 link is has 4 point that pivot at the chassis and at the rear keeping the rear end square as it moves. There is also a pan hard rod that keeps the rear centered and prevents it from swimming from side to side. I dont' think that a ladder bar has that, but I could be wrong.

 

i am not doing any of the work on the car, the car is going to a pro shop . And Jeb you are right about 4link being better for the street, but i was told by a friend of mine that its not . soi take you word for it over his.

 

You will still need a panhard bar or track locator with ladder bars. A panhard bar is a better choice for a street/strip car.

 

lots of nitrous

 

Ladder bars offer less adjustability that 4-links, both use a "track locator" which is either a panhard bar on the rear or a y-shaped locator attached to the 4-link/ladderbar cross-member up front.

Here's some fundamental differences:

4-links are infinitely adjustable. You can completely move the instant center around ANYWHERE you want it. They have more pivot points which is what you want in a street car, in other words they offer better articulation of the chassis.

Ladder bars are fixed length, which means other than moving the instant center up and down you cannot move it forward or backwards. You can change the tire contact this way but no other adjustability. Ladder bars tend to be a lot more violent on launch as well. And, they do not have the pivot points or articulation that a 4-link offers. They are also longer and more difficult to package. But they are less expensive and simpler to set up (because of their given "less adjustability").
-Jeb

 

I hear this kind of stuff all the time, and usually have to educate the buyer before he/she wastes their money and our time, so here goes....

Yes, you need a track locator device, whether it's a diagonal link (between front eyelet on one side and rear eyelet on the other), a Panhard Rod (brace between a fixed point on the chassis - hard to find on a Vette with stock frame -and the axle housing itself), or a wishbone (best method - fixed point in front to both axle tubes or two sides of the center section).

As to 4-link adjustments.... being I'm a drag racer as well as a shop owner, I can tell you in a nutshell : there are 1001 points of adjustment, with only about 4 that work on a 4-link... very easy to get lost, and NOT something for the novice!

Ladder bars are VERY violent (have this setup on my 9 sec. Chevelle), but are easy to tune. Easy to set up in the car.

Now..as to feasability and price: Are you quite ready to spend, oh say about $10,000 or so on this car? (this is a kind estimate) The rearend alone will set you back at least 3K by itself, plus the cost of suspension parts, brake, etc (you can reuse your stock brakes if you're handy with a lathe and mill) and the back-half frame rails to do the job properly. Not to mention the labor costs involved (this is NO PLACE for a "as long as I buy the beer for my buddy" type deal) for a professional shop to do the work. Plus, consider that rod ends are a consumable item (both 4-link and ladder bar), and good 4130 ends are nearly $200 EACH (that's 8 for a 4-link and 6 for a ladder bar setup), which you have to replace on a yearly basis at the minimum. You'll also DESTROY any semblance of street manners (goodbye cornering above 20 MPH), and of course, the ride quality will suffer. I could go on and on....

Remember this: a street and strip car will do neither as well as purpose built cars - race cars are designed for the track, street cars are designed for the street...simply put, get a purpose built car, or stay at your current power level. Good luck in whatever you decide to do.

 

The cost of the setup is $6300 with out the center section, and i say about another $1300 for good top of the line center section, that puts me at about $8000. The car is going to be more of a race car, the motor is out of the car and am in the process of building a new one. the goal is to go 9.00 ET on a good day .

 

Check out hoovers web site.. he did the 9inch conversion - I think hes also a forum member.. doa google search for hoover LT1 corvette and it should bring it up

 

Is this tubbing the car and using some real tires or staying with a "stock look" type of arrangement? For the money, if I were going that far, tubs and 15x33's would be in the picture.... but to each their own.

 

tubs and 15x33s are in the picture

 

***** that.... REAL men do it with 10.5"...
-Jeb