309 Front Arb Or Not?

[Alan_M 66 1 Cars]

I'm in the middle of rebuilding a 309 beam that will have a 24mm ARB and ZX arms chucked onto it, otherwise standard apart from the GrpA mounts. I shall be running the Bilstein Challenge spec shocks on it.

 

I am planning to add a 309 front ARB to the setup given the beefing up of the rear, but I am contemplating replacing the springs with something better matched to the Bilstein Challenge shocks up front. The springs are currently the SBC Roadspeed progressive type and I was looking at replacing them with the Tarmac spec springs from Peter Lloyd that apparently are rated 190Ibs.

 

Now, if I replace the springs is there any need to beef up the ARB, as both additions may prove too stiff. I read a thread some time ago regarding running stiffer springs and that beefing up the front ARB isn't required. Or does this just apply to seriously stiff springs, i.e. 250Ib?

 

Can someone shed any light on this or is it 'suck it and see'?

[Baz 421]

Not selling up now then Alan?

 

It may be a case of seeing what your personal preference, but with a 24mm rear ARB then i'd say yes, although it really depends what you want to do with the car etc too.

[Miles 331 1 Cars]

what tyres are upi planning on using?

[Alan_M 66 1 Cars]

what tyres are upi planning on using?

 

Road tyres for now (Alloy Mi16 dictates that), I have a choice of F1's and Parada's. But that may change once I drop the GTi6 lump in

[Alan_M 66 1 Cars]

Not selling up now then Alan?

 

It may be a case of seeing what your personal preference, but with a 24mm rear ARB then i'd say yes, although it really depends what you want to do with the car etc too.

 

Figured that I had spent too much money on it just to give in now, upgraded rear beam, proper quickrack, plate diff and brake setup to go on. Not to say that I may sell it all next year.

[Miles 331 1 Cars]

If using road tyres I would stick to the normal 205 bar, But if you;ve got all the 309 bit's give it a try and see what you think

[Henry 1.9GTi 36]

I can safely say it will understeer like a an arse.....

 

 

 

.....with a snapped rear arb

 

soz not much help, I have a new 25mm arb ready to go on just waiting on an endplate, also on road tyres and similar bilstein sprints so will let you know how it feels. My beam is a 205 one though.

 

Live in the same place and never seen your car! I did see a miami with 1.6 badges on the side and Mi16 badges on the back some years ago at the three mile cross mini roundabout, tried to cycle after it with lust in my eyes lol wasnt you was it?

[Alan_M 66 1 Cars]

I can safely say it will understeer like a an arse.....

.....with a snapped rear arb

 

soz not much help, I have a new 25mm arb ready to go on just waiting on an endplate, also on road tyres and similar bilstein sprints so will let you know how it feels. My beam is a 205 one though.

 

Live in the same place and never seen your car! I did see a miami with 1.6 badges on the side and Mi16 badges on the back some years ago at the three mile cross mini roundabout, tried to cycle after it with lust in my eyes lol wasnt you was it?

 

Probably was me, mines got 1.6 badges on it, an Mi badge on the back. And I go across that roundabout to work.......

[Henry 1.9GTi 36]

well hope to see your pug on the road again soon.

[mfield 20]

I'm using a 205 rear beam with a 26mm arb, 309 wishbones + arb,tran-x diff,280lb springs and r888's. Around cadwell it was great, i don't recall any major understeer and it was flicking the back end out with ease but felt very controlled. Going into the mountain their wasn't much quicker that i came across all day except a few kitcars.

[swordfish210 20]

My suspension set-up consists of,

 

Rear: 1.9 GTI rear beam, ZX trailing arms, Koni Yellow dampers.

Front: 1.9 GTI set-up, polybushed wishbones, Bilstein OE dampers, Eiback progressive springs, Quaife quickrack and a 309 GTI ARB

 

and i can say that it doesnt understeer at all really. I'm doing some math at the moment on ARB stiffness trying to find out what thickness would be throreticly best for my set up, and i'v yet to try the standard arb to see if is any better though.

[Alastairh 47]

James ran a 24mm arb and 309 arb setup and seemed notice a good difference when adding the front arb. But he was never running as fancy shocks as you, so it might be a suck it and see.

 

Your F1's will get ripped apart though on that setup. Mine with 23 torsion, 25 arb and 180 lb springs didn't last that long.

 

Are you sure you want to read too much into this knowing your going to put a iron block lump in the bay in the future? That will change things.

 

Al

[Anthony 1,000]

309 front ARB works well in conjunction with 24mm rear ARB in my experience on standard TB's and lowering springs.

 

I'm not convinced that 190lb front springs are a good move unless you're fitting thicker rear TB's at the same time, otherwise it's likely to wash out easier at the front. If you do use the stiffer springs, I'd leave the softer 205 ARB in.

[Anthony 1,000]

Your F1's will get ripped apart though on that setup. Mine with 23 torsion, 25 arb and 180 lb springs didn't last that long.

Mine didn't when I was running pretty much the setup that Alan is proposing - it's just your driving Ali

[James_R 3]

Mark it's a 27mm ARB, or should be :s and yeah that needed a bigger front ARB must be awesome now

 

Alan, try some Kuhmo RS2's £50 a corner from camskill help no end.

[Alastairh 47]

Mine didn't when I was running pretty much the setup that Alan is proposing - it's just your driving Ali

 

The cheek.

[mfield 20]

Mark it's a 27mm ARB, or should be :s and yeah that needed a bigger front ARB must be awesome now

 

Alan, try some Kuhmo RS2's £50 a corner from camskill help no end.

 

 

I work with numbers all day and i still can't remember the exact setup most of the time, as James says i'm running a 27mm rear arb not 26mm

 

I'm using James old setup but with the 309 front arb

 

So thats:

 

205 beam

solid mounts

24mm tb's i think

27mm arb

Ast shocks

zx trailing arms

309 wishbones

ast front shocks

280lb springs

309 front arb

Tran-x diff 45/45 I think

Top and bottom strut braces

R888 tyres

and the std safety devices roll cage

 

The car was only let down with it's std power plant and gearbox being a 1.9 8v, really needs more power and a shorter box. Was running out of gear in the twisty bit by the club house hall bends at cadwell but the next gear was too long to go up into and still pull with the lack of grunt from the 8v.

 

Was getting a huge amount of fuel surge with well over half a tank coming out of that fast right hander charlies ? and onto park straight. The thing just gripped all the way around with very minimal throttle adjustment

 

Don't suppose anyone knows the amount of oil capacity in a dry sump do they ? looking into making my own by welding an insert into a mi sump to direct the oil for scavenging, then making a bracket for the pump to attach to. The rest is straight forward.

[tagy 1]

Road tyres for now (Alloy Mi16 dictates that), I have a choice of F1's and Parada's.

 

I would avoid the parada's if you want to drive quickly at all in the wet.

[Alastairh 47]

I would avoid the parada's if you want to drive quickly at all in the wet.

 

Stiff suspension in the wet doesn't really match.

 

Personally with mine i feel safe to do well over a ton in the wet (Not that i do it regularly), and even on the greasy round abouts you can keep up with modern day 'hot' hatches. As i found out this morning...

[James_R 3]

Ton in a straight line is fine, just stopping or turning that's not good at a ton in the wet, regardless of tyre.

 

I've got agree on the washout of prarada's in the wet, they only good cause they're cheap and don't die in the dry, they're not a good "road tyre"

 

Semi slicks however they're awesome all the time, till they're near tread bars:s but thats the same for all tyes.

[j_turnell 134 3 Cars]

Same with Anthony i found 24mm rear with standard 20mm torsion bars worked very well when combined with the 309 front, handled very neutral and cant say i had any problems with tyre wear either and i was using F1's

[Henry 1.9GTi 36]

this will be my setup soft(ish) front with the bilstein sprints -25mm(ventra rubbish) 309 wishbones and arb then standard TBs at the back with a 25mm arb. Iv'e got some 23mm bars to go on the back but will wait untill I get coilovers and 275 ish lb springs. Can then play about with arb sizes upfront and see how it goes.

 

Have to say that if you don't uprate the rear of a 205 its so lifeless and dull to drive. Great as standard but all these lowering kits just ruin the car although my experience is exaggerated going from 25mm rear 21mm front to 0mm rear and 21mm front really can't wait to get this new arb in there!

[C_W 3 1 Cars]

If you run too stiff a roll bar with softish springs then you might find the roll bar becomes the spring making the ride choppier and a lot less traction unless you have a proper LSD.

[Anthony 1,000]

If you run too stiff a roll bar with softish springs then you might find the roll bar becomes the spring making the ride choppier and a lot less traction unless you have a proper LSD.

I didn't personally find any problems with ride quality or traction when I was running standard 20mm 309 TB's. Like I said, in that configuration, the 309 ARB worked well and made the car more balanced, especially on higher speed corners.

 

However, when I fitted 22mm torsion bars to the back (and dropped to a 22mm ARB) then the 309 front ARB definately reduced traction. What I believe was happening was that because the rear of the car was now stiffer, it would lean harder than usual on the outside front wheel when cornering - not a problem in itself, but the stiffer 309 ARB was then taking all the weight off the inside front wheel and you'd just spin away any power you tried to put down (it was a nightmare in the wet)

 

Swapped back to a 205 front ARB and the traction issues were much improved, although it does need stiffer front springs really to balance it back out again

[Alan_M 66 1 Cars]

Mark it's a 27mm ARB, or should be :s and yeah that needed a bigger front ARB must be awesome now

 

Alan, try some Kuhmo RS2's £50 a corner from camskill help no end.

 

I would love to run semi-slicks but I have the fear of grenading my alloy Mi lump.

 

If you run too stiff a roll bar with softish springs then you might find the roll bar becomes the spring making the ride choppier and a lot less traction unless you have a proper LSD.

 

I forgot to mention that a Trans-X diff is being fitted too, but the general opinion is that with stiffer springs a 205 ARB will be suitable?

 

Does anybody know the rating of Eibach/SBC springs? (Soft I'd imagine....)