mnow

Came home from work today to find a present on my doorstep, the new rear sway bar I had ordered from madvet.com! :thumbs:
My 1980 L-48 didnt come with a rear bar, so this had been high on my list of "to do's". I went with the medium sized 3/4 inch bar.
I didnt want to eat dinner while it was hot anyways, so under the car I went!
The kit was from Vette Brakes & Products, Inc. and included Poly bushings, and all the hardware needed. Frankly, I was a bit nervous, since aftermarket parts rarely seem to fit just right, but I sure was impressed with the kits quality! Everything bolted up perfectly, and for once I didnt have to fabricate or alter a single thing.
The proof was in the pudding tho (heck yeah I took it for a spin). I ran a series of "S" curves near the house, and noticed a huge difference in body roll, and even though I was pushing it much harder than normal, the tires didnt even sing!
For all you chaps thinking about doing this, this has been the best, and most noticable improvement I've made to the car yet, and it only cost $119.00 (134.98 including shipping to the west coast via fed ex). So why put it off any longer? I'm jazzed I didnt!
The whole job took about 2 hours, smoke breaks and beer breaks included.
Take it easy folks! (life, not the corners)


[Modified by mnow, 11:31 PM 9/2/2003]

Shark Racer

What is the rest of your suspension like?

My body roll is not very nice, but the car handles pretty neutrally. Not sure if a bigger rear sway bar is what I want.

-Steve

mnow

The rest of my suspension is decent, although the original rubber bushings up front are starting to show their age. Have new monroe shocks (sense-a-trac). Been thinking over redoing the front in graphite-poly, but havent decided on the kit to buy. Was hoping do get some more input, and do my homework first. Even with the aging front end, the improvement was very noticable.
If I were you, I would most likely shoot Vette Brakes a call, and ask them what would be a balanced setup for you. If you are up-sizing you might need to do both ends to keep it neutral.

hunt4cleanair

Quote:

I went with the medium sized 3/4 inch bar.

That's a monster bar for the rear and it is recommended one match the bars front and rear to avoid oversteer on the front side. Your L48 is sitting with a 7/8" front bar and you may wish to consider moving up to the 1 1/8" Gymkhana bar.


[Modified by hunt4cleanair, 5:14 AM 9/3/2003]

427V8

I like mine too :D:D

UKPaul

mnow,
Thanks for the post :thumbs: 2 hours to fit, including smoke breaks AND beer breaks, sounds like my sort of job :D What size front sway bar are you running???
:cheers:

flynhi

Hunt4cleanair is exactly right. If you are running a 7/8 front and 3/4 rear you are setting yourself up for some massive oversteer and end swapping. Change that front to a 1 1/8.

Personally, I like 1 1/8 front and 5/8 rear.

See the ADDCO web site for a table that compares relative stiffness of various diameter sway bars. Check it out - the big difference in stiffness for small change in bar size will surprise you.


[Modified by flynhi, 9:31 PM 9/3/2003]

MN-Brent

The 82 Gymkhana set-up comes with 1 1/8 front and 7/16 rear with steel spring.

This is a much smaller rear bar than other years which all seem to be 3/4. Could this be due to the lighter 80-82 rear end or maybe even a softer spring rate?

Brent...

PatsLs1vette

i just took mine out tonight after swapping to a 1 1/8 front and 3/4 rear and your right big difference in what i had with only a 3/4 in front.Now i need a new rear spring and bilstien shocks.Thanks gene sway bars work great.

LT1driver

big block cars of 66-74 had 9/16 rear bar as did the F-41/gymkahana pckges for all cars of that era, front bar was I believe somewhere around 1"

mnow

I measured my front bar with a caliper before I ordered, and it looked to me to be a 1 inch bar (unless I jiggled the caliper taking it off). Perhaps a previous owner upsized it already up front, if in fact a 7/8" bar is a stock one. When I looked in the ecklers catalog it recommended the 3/4 bar for use with a 1" front bar IF there was no OEM rear bar, so I never gave it a second thought. Guess I'll have to go out after work tomorrow and double check it (too dark now), so thanks for the heads-up guys. If thats the case I'll definatly upsize the front to the 1 1/8th bar, when I plug in the new poly kit, if not sooner. Other than that, I pushed the car even harder today, and it rode like it was on rails, but havent pushed it to the point of drifting yet. I guess I wont either til I get this sorted out.
Keep 'em rolling !
~Michael

Shark Racer

My 78 came stock w/ FE7(Gymkhana).

1 1/8" front, 7/16" rear. 550 front, 300 lb rear steel.(7-leaf)

I'm running 550, 360fg,same sways. Just wondering idly about the larger rear. My car handles neutrally and I really am not interested in upsetting the balance a whole lot. A lot of people think the VBP rear sways are just too large.

mnow

I think I'm going to find a big empty parking lot tomorrow, and see if I can get the car either doing 4-wheel drifts, or out of shape completely. Hope the local johnny-law doesnt mind :blueangel:

hunt4cleanair

[QUOTE]My 78 came stock w/ FE7(Gymkhana).

1 1/8" front, 7/16" rear. 550 front, 300 lb rear steel.(7-leaf)QUOTE]

Hey Pacin:

Are you still stock? Shocks?

hunt4cleanair

Quote:

The 82 Gymkhana set-up comes with 1 1/8 front and 7/16 rear with steel spring. Could this be due to the lighter 80-82 rear end or maybe even a softer spring rate?

I've been looking at all the C3 suspension setups and the best explanation I've come up with is the fact that by late model C3...the cars had bloated up from catalytic converters and rubber bumper absorbers and brackets among other weight producing safety and emission items.

In addition, I believe Corvette engineering simply figured out how to dial in these suspensions specifically for Gymkhana racing in the 70's. Remember...the big blocks were great race cars but did not have the nimbleness of the smallblock race cars (LT1s and ZR1s).

So I believe it was these two factors that produced the FE7 suspension setup for the lowest horsepower output ever (next to the Blue Flames)!

flynhi

During the C3 run, tire technology changed dramatically. There is simply no comparison between a red line bias ply F series tire installed at St. Loius in 1968 and a steel belted radial 60 series tire installed in Bowling Green in 1982.

GM engineers responded to these better tires with changes in the suspension setup.

Shark Racer

No, I never got a chance to drive the car completely stock. The front suspension was rebuilt 10 years ago, and they installed 460 springs, along w/ bilstein HD shocks. I later upgraded to the 550s, then swapped out the rear 7-leaf for a 360# fiberglass spring. I finished with Bilstein Sport shocks and smart struts. I'm very much -not- stock now.

-Steve

Enad

Hunt4, I think if you look at the specs. the 80-82 models are the lightest of the bunch unless you go back to 72 and earlier.

I have a ADDCO 1 1/8" bar on the front and a 5/8" on the back. This is just perfect for my car. :thumbs:

I've had the poly bushings on/off/on and finally took them off because I was tired of hearing mouse chirps all day long. There is not enough difference over rubber bushings that I cared.

Dane

hunt4cleanair

Enad...you're absolutely correct! forgot about those aluminum struts, crossmembers, etc to reduce that weight. Here's the weight by year

Year Weight

1968 3210
1969 3245
1970 3285
1971 3202
1972 3305
1973 3416
1974 3388
1975 3529
1976 3541
1977 3541
1978 3572
1979 3503
1980 3336
1981 3307
1982 3342

flynhi

Hunt4,
I'm curious as to where you got those numbers.....