Rear IRS Suspension options

[bow]

Hi all,


I know much has been said about rear suspension on bugs and switching them and all that jazz, but what does the average person without the want to switch trailing arms and nothing Porsche going on out back. is there a good "better than stock option"? i have tried many setups during my trek for something better and i havent seen much. that being said i just bought a set of kyb gr-2's and was wondering if this is gonna help much ,also i havent changed my torsion bars but i dont see much being changed by doing that.i have all the standard rear assisting stuff like a engine brace, kafer brace, rear sway bar. so anyone else got any ideas on how to expand the weak point mostly being the shocks.

thanks, brennan

[evilC]

Brennan, the big issue you have to address is 'what do I want out my car' I cannot see how anyone can pass comment without knowing where you want to take it? You've not even told us what vehicle it is.

evilC

[bow]

ha yes sorry it was kind of an open end comment. i did specify that its a independant rear suspension type 1 beetle....... That being said i also added that it would need to be better than stock but not wild custom porsche rear end. so......... basically im looking for something better than just gr2's

[evilC]

For comfort, performance and whats wrong with the standard? Why does it need improving in your eyes?

evilC

[bow]

beacuse it doesnt seem right under extreme cornering the class i want to race in here around town doesnt allow me to change to a porsche arm but the rear seems like it still rolls too much

[wrenchnride247]

Have you replaced the spring plate bushings? Bilstein has a stiffer feel than GR-2's

[Steve C]

Hi

Good input so far, the VW factory listed optional 23.5 mm bars on bugs rather than 21 mm, these same bars were also factory on Type 3 wagons and were also found on 944 Porsches.

They are very good budget upgrade.

Steve

[bow]

ahh i see steve thanks for that but wouldnt that involve changing the torsion housing

[Steve C]

Hi

No they are direct replacement for the stock bars, just remove the old ones and refit the heavier ones, or if you want you can go for heavier again after market bars, but they cost more $$.

With correct rear torsion bar sizing you don't need a rear sway bar, but can use the sway bar for fine tuning

Steve

[bow]

sweet that sounds like a good upgrade

[evilC]

Originally Posted by bow

beacuse it doesnt seem right under extreme cornering the class i want to race in here around town doesnt allow me to change to a porsche arm but the rear seems like it still rolls too much

Now I see where we are going -
Steve's upgrade is spot on. The easiest place to get the torsion bars is off a 944 or 924S where the 23.5mm bar is standard. The later 25.5mm 944 bar is a better option still for a competition car that is also used on the street rather than a street car used for competition , if you see what I mean. If your regs will allow it a coilover damper in the rear can be used to tune the wheel rate and ride height. Also the 16mm rear AR bar from a 944 is a useful addition but it will probably require a front upgrade to compensate.

evilC

[bow]

youll have to help me out what is a ar bar and coilover damper? sorry about my ignorance

[evilC]

The Anti-Roll bar is the 'sway' bar. This connects the two sides of the suspension and as one side compresses and the other unloads the bar is forced into twisting, which it resists. Thus in roll (hence the English anti-roll bar) it resists that roll to keep the car flatter. However, by resisting that roll the rear axle wants to go straight on at bends so the tendency is to oversteer. This has to be compensated for by making the front want to do the same to balance it out, thus making the front stiffer in roll by increasing the AR bar is the usual option.
A coilover damper is a damper (or less accurately a shock absorber) that has a coil spring wound around it. Typically these are most common on the rear suspension of motorcycles.

evilC

[bow]

oh lol i knoew all of that just a different explination lol

[evilC]

Originally Posted by bow

oh lol i knoew all of that just a different explination lol

Here endeth the english lesson