Paul L

In that regard, this may be of interest.
http://www.ncrs.org/forum/tech.cgi/noframes/read/117399

The Dude

On second look I think it will go on without dropping the exhaust. Will most likely have to pull the spare tire carrier, though.

I'm going to post my theory on your setup here and see what the experts say since going around corners isn't my thing:

When he started, Cali's car had the stock '68 front anti-roll bar in front and none in the rear. (I don't recall the diameter of the original stock bar in front. Maybe 3/4"?)

He's upgraded the front roll bar to a stiffer, larger diameter bar (1 1/8") that was a takeoff from a 1976 FE7 car. There's some debate about whether it would be a good idea to retrofit the car with the matching rear 7/16" FE7 bar as well--some said yes and others said it's not needed. Here's where my theory comes in and why I think he ought to install the rear bar. Pick it apart and tell me whether my logic is incorrect.

The car exhibited quite a bit of roll when cornering hard in its stock condition. Really excessive, IMHO. He upgraded the front anti-roll bar to a stiffer unit. He still has no bar in the rear. It seems to me the new configuration could cause an oversteer problem under hard cornering. I know you cornering guys would prefer a little oversteer if you had to err in one direction or another, but I think it may be excessive in this configuration. Here's why:

The front of the car with the new larger diameter bar will now want to go around corners flatter (less roll) than before. BUT, the rear of the car will still want to roll as much as it ever did since there's nothing in the rear "helping" the new, stiffer front bar. Why? Because it's not a race-prepped chassis and there is going to be flex. I may be tripping, but it seems to me that he would want to install the matching FE7 bar in the rear to help counteract this condition and move the car closer to neutral.

I mean, why would GM have included the rear bar on FE7 cars (and some big blocks) if this were not the case?

Anybody?

Cali,68,L-79

Jack that's a good question but with all the "self professed experts" on the forum with varying thoughts whose to say whose right.

Paul L

As promised, now on EBay.
http://cgi.ebay.com/ebaymotors/ws/eB...tem=2462614986

The Dude

Personally? I would tend to defer to GM on this one. The FE7 cars also had/have different springs to complete the "Gymkhana" package and that may need to come into play. But I somehow doubt the cars with that RPO came with the rear anti-roll bar as a gimmick for the salesman to show potential customers. Having said that, all I know is that I don't know poop on this subject. Maybe someone else does--I'm curious now.

EDIT: I've posted one of those "Hey, come over here..." topics in the autocross/road racing section. Perhaps someone with experience along these lines will have a definitive answer one way or the other.


[Modified by The Dude, 3:59 PM 2/23/2004]

73jst4fun

I installed a 3/4" rear sway bar along with the 1 1/4" bar on the front along with the TRW 315lb. spring, and GM gas shocks. I tried the poly bushings all around and the vette was harsh on the street. I removed the poly bushings and went with the OEM rubber. Now the car is very comfortable so I have now a vette that handles very good in the corners with little body roll yet has a comfortable ride. I've read about this combo in several vette books and it 's working for me :seeya

Ganey

Some might want it one way & someone else another. If you want an objective comparison, see 77 Facts on my website. A standard of comparison is needed. A good standard of handling is the Road & Track slalom course.
77 w/ FE-7 sets new record in 77 with 63.6 mph. "hampered by stock air pressures". Later matched by a Ferrari 512BB.
For reference, Mario Andretti turned 63.4 in a 1999 Corvette.
So yes, it works well.

If someone wants ride & handling they might want to add just the FE-7 bars.

Have FE-7 & like it.

:cool:

Twin_Turbo

do you have a "post default FE-7 message" button ? :lol:

Ganey

Almost.
Shoot straight & don't type. (default)

:cool:

flynhi

Did you remove ALL poly bushings (A arms, strut rods, sway bars, etc) or only the sway bars?

gkull

IMO - flynhi said it all - It really comes down to your tires

Quote - VBP sells packages that (IMHO) must be matched with good to very good tires to perform well. I ran BFG T/As with VBPs 1 1/8 and 3/4 bars and experienced pronounced oversteer. with 17" wheels and very good tires, the VBP combo feels very good.

Too much rear bar essentially converts the independent rear suspension into a solid axle.

For most street use, OE front bar and no rear bar performs very well.

**************************************** ****************

I should say that "Solid axle" doesn't occur with less than 420 inch pound springs rear springs and 3/4 bar!:)

Years ago I had a rather lower ratio 340# or so mono sprung 79 with 275/60/15's on a 8.5 wheel with 4.5 BS and Whacked the tires into the frame on a bad dip high at speed. (airborne)
I got rid of the spring and went to 17 inch wheels right after that because it scared me so much.

Most of you guys drive so slow because of where you live. I would too becauses of traffic and bad roads. Always have fun and be safe!

Take it to the track - auto - X drag race on play days, and if your really into it go out for a track day at your local road race.

Make your car the best you can for the on ramps and go for it when the traffic is clear! :party:

LiveandLetDrive

^^^ best post ever. :steering:

aharte

The sway bars, springs, tires, and shocks are all matched together to acheive what the engineers want on a new car. Change any of these variables, and the car could handle very differently. We've certainly all changed our tires from the stock set, and most of us have also changed the other components. There's no one answer to this question.

As a side-note, I've heard that a Porsche engineer claimed that the minimum time required to properly tune the shocks, springs, etc. on an otherwise completed new production car is around 18 months. That's with very skilled engineers, a test track, and lots and lots of money. You're never going to get everything perfect on your own. If you have time and money to burn, try some combos to see what you prefer, but don't expect a magic solution.

I would say FE-7 is probably great if you get the springs and shocks to go along with it, but its no longer going to be optimal with modern tires. Its still probably better than the random guessing that most people seem to do though.

The Dude

Thanks. Bottom line: Couldn't hurt to try. Results will depend on the car, the other installed components and driver preferences.


[Modified by The Dude, 12:44 PM 2/24/2004]

thevetterisbetter

Have the FE-7 set-up, with the 7/16 rear bar, car runs on rails. My front end is a little lighter with the aluminum heads and intake and headers, but the springs are for a stock suspension.

73jst4fun

The sway bar for the front and rear are the only place that has the poly bushings, I tried replacing the stock bushings on the shocks, A arms, motor mounts, trans mount, fiberglass spring etc with the poly bushings....that's where my mistake was, felt every bump/fibration....went back to the OEM rubber bushings and now it's fine with less body roll with the sway bars equally balanced for the car. The VBP adjustable rear strut rods come with poly bushings and they do not affect the ride. :seeya