| Author |
Message |
Philip Airey (Pma1010)
Member
Username: Pma1010
Post Number: 398
Registered: 7-2002
| | Posted on Sunday, August 31, 2003 - 10:09 am: | |
Newman
If you've got access to a bigger rear bar, my advice would be just to try it. Personally, I'd want to try it at a "forgiving" track, like Gingerman to get a true perspective on the resulting behavior but either way, experience is worth a thousand words.
Brent
I went with an adjustable rear bar as I didn't know "how much" more rear bar I'd want. Stock 308 (GTB) is 14mm. Later (328) was 15mm. So, which is "better" 15? 16? 17? 18mm? More? I had a bar made up with the equivalent of 15mm and 18mm settings. I've used both, prefer the 15mm setting so far. It's not fun getting too much oversteer in these cars. They come round very quickly at speed and the resulting spins last time flat spotted 4 good tires.
One think to think about, if it is an understeer/oversteer behavior you are trying to fix, I think Rob and others would strongly recommend playing with tire pressures before ARB settings. You can get them to be far more neutral in handling w/o changing the ARB settings. As I have said before, I was running 36F, 32R on the track (street tires) with good results.
The ARB will reduce body roll. I'd guess you'd want to increase both F & R proportionately to preserve the same balance, but don't know if you'd be better off with stiffer springs (also available). However, you're getting beyond my knowledge base. Rob S thoughts?
Last, the adjustable ARB was available from SANER Performance Fab. Price included the endlinks. They advertise in GRM. |
Newman (Newman)
Intermediate Member
Username: Newman
Post Number: 1306
Registered: 12-2001
| | Posted on Saturday, August 30, 2003 - 4:51 pm: | |
Ill try the stock GTS bar first because I can get my hands on one to try. I dont plan on any track time either. I find the car pretty neutral, I get the usual understeer under throttle and it tucks in if I let off in the same turn. I dont really like the plowing, I would rather deal with oversteer so I can power through a corner rather than play with the throttle. |
Brent Lachelt (Brent_lachelt)
New member
Username: Brent_lachelt
Post Number: 50
Registered: 4-2002
| | Posted on Saturday, August 30, 2003 - 2:02 pm: | |
PS: This would be for street use, so a track set up is not nescessary. |
Brent Lachelt (Brent_lachelt)
New member
Username: Brent_lachelt
Post Number: 49
Registered: 4-2002
| | Posted on Saturday, August 30, 2003 - 1:35 pm: | |
Philip,
I was thinking of getting a bigger rear sway bar on my 1982 308 gtsi. Want a little less roll. Would you recommend larger bar or an adjustable bar. Mine looks to be the factory bar.
Superformance sounds like a great deal at $250
Thanks
Brent |
Philip Airey (Pma1010)
Member
Username: Pma1010
Post Number: 397
Registered: 7-2002
| | Posted on Saturday, August 30, 2003 - 1:04 pm: | |
Newman
Superformance sells 18mm bars, but remember, a jump from 14mm to 18mm is a BIG change and you don't want too much rear bar. FYI, I bought an adjustable rear bar for my GTB - about $250 incl. end links. I have found that running street tires (since changed for comp tires), 36/32 (F, R pressures) and the softer (15mm) setting produced a great track set up. With the bar set to 18mm, I found it was too easy to spin.
HTH |
Newman (Newman)
Intermediate Member
Username: Newman
Post Number: 1304
Registered: 12-2001
| | Posted on Saturday, August 30, 2003 - 11:51 am: | |
I think i can get my hands on a GTS bar. I would like a little more oversteer. Thanks. |
Mark Eberhardt (Me_k)
Member
Username: Me_k
Post Number: 668
Registered: 5-2002
| | Posted on Saturday, August 30, 2003 - 7:18 am: | |
There are 3/4, 7/8, 1" aftermarket bars available too if you want more. The GTS has a softer chassis, so it needs a little more stiffness in the bars to get the same effect. |
Philip Airey (Pma1010)
Member
Username: Pma1010
Post Number: 395
Registered: 7-2002
| | Posted on Saturday, August 30, 2003 - 7:10 am: | |
Early GTB = 14mm rear bar, later = 15mm. GTS = 18mm. Different spring rates etc too. I put an adjustable rear bar on my 77 GTB toget more oversteer/less understeer (acts like a 15 or an 18). Yes you can tell the difference. |
Paul Jeffery (Peajay)
Junior Member
Username: Peajay
Post Number: 124
Registered: 4-2002
| | Posted on Friday, August 29, 2003 - 3:27 pm: | |
Usually because an open car looses stiffness due to not having the roof, so the thicker bar is to compensate. I would expect this to be true for Ferrari also. |
Newman (Newman)
Intermediate Member
Username: Newman
Post Number: 1299
Registered: 12-2001
| | Posted on Friday, August 29, 2003 - 2:17 pm: | |
Why does the GTS have a thicker rear bar? ANyone swap one onto a GTB and see a noticable difference in roll. |