Club G40 Forum

Technical => Chassis & Braking => Topic started by: Justin14100 on October 31, 2011, 11:35:08 pm

Title: Anti roll bar options.
Post by: Justin14100 on October 31, 2011, 11:35:08 pm: Hi guys, currently I'm running a PPS subframe and don't really want to have to rely on stiffer suspension for the anti-roll.
Salzmann incorporate it into their frames some how like this:
(http://www.vwtuningsalzmann.de/g409.jpg)
and I have been thinking of making up something similar to just mount onto the frame / wishbones.
alternatively I could do what Thomas has done and run a rear anti roll bar setup but I think this could induce understeer:
(http://forumbilder.se/images/44201191544PM9be0.jpg)
What do people think? is it worth fabricating?
Thanks.
Title: Re: Anti roll bar options.
Post by: cheys03 on November 01, 2011, 07:18:33 am: I can't offer much engineering help I'm afraid, but I will be very interested indeed to buy the end product. I've gone to softer springs with updated shocks for ride quality but find it a bit rolly with a Stage 3 subframe and I was even considering going to a Stage 2.
Title: Re: Anti roll bar options.
Post by: Jezza-7 on November 01, 2011, 05:57:59 pm: Quote from: cheys03 on November 01, 2011, 07:18:33 am
I can't offer much engineering help I'm afraid, but I will be very interested indeed to buy the end product. I've gone to softer springs with updated shocks for ride quality but find it a bit rolly with a Stage 3 subframe and I was even considering going to a Stage 2.

What shocks you got? I heard that h&r and another make, make the steering rods sit higher and dont go too well with a stage 3 frame. How ever gaz kits are spot on.
Title: Re: Anti roll bar options.
Post by: Andy on November 01, 2011, 07:20:51 pm: Quote from: cheys03 on November 01, 2011, 07:18:33 am
I can't offer much engineering help I'm afraid, but I will be very interested indeed to buy the end product. I've gone to softer springs with updated shocks for ride quality but find it a bit rolly with a Stage 3 subframe and I was even considering going to a Stage 2.
Stiffer springs are definitely recommended with the Stage 3 frame - we've been running my car with soggy 9 year old FK springs/shocks as a worst-case, as they were unduly soft even with the original TCAs and ARB. Out of interest, what springs have you tried? I'll be fitting my KW coilovers, and playing with the spring lengths and rates to tune the ride and handling to my taste - on track the FKs give comical body roll.

Our main reason for not producing an ARB frame is the additional cost it'd add - and the fact that most customers have more fast road or track focussed cars where fitting stiffer springs is not an issue and far cheaper. For those wanting a stage 3 on a daily driver an ARB may be a good option, but I think it's worth playing with springs first where possible.
Title: Re: Anti roll bar options.
Post by: cheys03 on November 01, 2011, 09:34:32 pm: Hehe, yeah, I now know why they are recommended!
The springs I'm using are standard items with a coil (very carefully, dremel and lots of patience so no heat) removed. Shocks are SPAX RSX I think (non-adjustable)
Don't get me wrong, I'm not a buffoon - I knew the soft springs and lack of anti-roll bar would be an issue, I wanted to find out how much of an issue.
Sorry to sidetrack the topic slightly. I'm happier with the softer springs, as the car's my daily and needs to be comfortable - will a Stage 2 be suitable for road use circa 150bhp?
Title: Re: Anti roll bar options.
Post by: Justin14100 on November 01, 2011, 09:40:11 pm: I have some FK Automotive springs and shocks from what I know of, they are as harsh as hell on bumps to be honest. I want to go with a softer setup like the H&R kit cause its a daily and I'm a bit tired of bouncing off the road haha.
I might give the standard bar a trim and try and mount it, I was worried it would try and lift the inside front wheel though and make things worse. I really want a car that'l be soft over the bumps but stiff on roll, as I can't afford active suspension I think the anti-roll is the best way to go.
Title: Re: Anti roll bar options.
Post by: Andy on November 01, 2011, 10:06:23 pm: I'm running caravan spring assisters in my FKs to stiffen them up - actually improved ride quality!
Title: Re: Anti roll bar options.
Post by: cheys03 on November 01, 2011, 10:13:26 pm: Quote from: Andy on November 01, 2011, 10:06:23 pm
I'm running caravan spring assisters in my FKs to stiffen them up - actually improved ride quality!
Whhaaaaaaaaaa?! Improved ride quality - awesome!
Title: Re: Anti roll bar options.
Post by: Richg40 on November 02, 2011, 07:03:47 am: What's the purpose of that rear arb pictured? Is it just mounted in 4 places to the rear beam?
Title: Re: Anti roll bar options.
Post by: G40supercharged on November 02, 2011, 08:53:51 am: Quote from: Richg40 on November 02, 2011, 07:03:47 am
What's the purpose of that rear arb pictured? Is it just mounted in 4 places to the rear beam?

The rear beam isn't a solid lump and the trailing arms can twist relative to each other. The standard G40/GT rear anti roll bar is just a rod that stiffens up the torsion beam. Looks like that ARB is taking things a bit further.
Title: Re: Anti roll bar options.
Post by: Yoof on November 02, 2011, 11:09:02 am: I think you could do this with relative ease- but dependant on what ARB/ blocks you use, and how you hang it from the subframe, determines how much work is involved.

Easiest option- use a stock Polo ARB and the g-laderseite ARB blocks, and buy a drop link to attach it to the rear clevis pin mount.

Potential problems are wheel clearance, length of droplink required for the stock ARB (which I think is longer than you can physically fit in- I.E you need a fatter ARB and a shorter drop link) which then in turn leads to custom blocks.

I'm currently planning a house move and career change- so don't have much free time, but I'll try and see what a Stage 3 frame fits like with the Polo ARB and G-Laderseite blocks at some point.

Yoof
Title: Re: Anti roll bar options.
Post by: Justin14100 on November 02, 2011, 11:38:36 am: surely running the Glader site ARB blocks will lower the frame significantly?
Title: Re: Anti roll bar options.
Post by: Yoof on November 02, 2011, 01:37:56 pm: Yes- altering the angle of the front plates and rear TCA mounts, without trying it I'm unsure how significant the alteration needs to be
Title: Re: Anti roll bar options.
Post by: confusionhunter on November 02, 2011, 07:39:40 pm: Arse, I have Fks coilovers..... doesnt sound like they are up to much..... wouldn't increasing the dampening help?
Title: Re: Anti roll bar options.
Post by: Andy on November 02, 2011, 09:46:00 pm: Mine aren't FK coilovers Mark, just the cheapo lowering springs. Liam was unimpressed with them when he drove the car just after I'd fitted 'em ages ago. If you've got coilovers then you can take your pick from alternative springs from Rally Design etc.
Title: Re: Anti roll bar options.
Post by: cheys03 on November 13, 2011, 07:09:56 pm: Quote from: cheys03 on November 01, 2011, 09:34:32 pm
Hehe, yeah, I now know why they are recommended!
The springs I'm using are standard items with a coil (very carefully, dremel and lots of patience so no heat) removed. Shocks are SPAX RSX I think (non-adjustable)
Don't get me wrong, I'm not a buffoon - I knew the soft springs and lack of anti-roll bar would be an issue, I wanted to find out how much of an issue.
Sorry to sidetrack the topic slightly. I'm happier with the softer springs, as the car's my daily and needs to be comfortable - will a Stage 2 be suitable for road use circa 150bhp?
Just a brief update - I'm back to the stiff Spax -40mm front springs... this is much better..!
Title: Re: Anti roll bar options.
Post by: Andy on November 13, 2011, 07:18:09 pm: Excellent! ;D
Title: Re: Anti roll bar options.
Post by: prankstar2003 on November 21, 2011, 10:57:52 pm: Andy, what are these caravan Helpers? Are they fitted in addition to or instead of your springs?