Page 1 of 2

Rocker tower brace

Posted: Wed May 23, 2012 9:33 am
by stylussprinter
I like Dave's brace between the rear towers so looked at the possibility on mine. However , my ARB links would foul the tube at that height (centre pivot bolts).
A compromise was to link the rear towers at the very top where I already have holes drilled to pivot my castor adjusters. The holes are only 6mm's so have drilled them out to 8mm's then linked the towers via a square (because it was in the shed :roll: ) 20mm's tube --- crush tubes added too :wink:
This still wasn't quite enough to clear the ARB links when the car is jacked. So removed my original ' U ' brackets bolted to the top shock mount and made new brackets with the rodend bolt hole as close to the shock bolt head as possible -- 6mm's closer.
Obviously I've yet to find out whether the brace will have a handling change that I can actually feel :|
Dave's passenger side bulkhead to bottom tower triangulation couldn't be done easily because my repairs were finished before considering that experiment :roll: plus I'd have not known for certain , if the exhaust manifold would clear the tube.
So , looks like a bolted version may be an alternative that's easier to do now the engine's back in place , even if less rigid :?:

Re: Rocker tower brace

Posted: Wed May 23, 2012 10:08 am
by CMA
Could you make a removable one in a similar style to your adjustable panhard rods, so you can fit it loose then turn it to lengthen it so its a tighter fit than just a bolted version?

Re: Rocker tower brace

Posted: Wed May 23, 2012 10:22 am
by stylussprinter
CMA wrote:Could you make a removable one in a similar style to your adjustable panhard rods, so you can fit it loose then turn it to lengthen it so its a tighter fit than just a bolted version?
If welding was possible with engine etc in place , then yes but probably only at the bulkhead end having a rodend would be the only chance of that --- ideally both ends need a ' U ' bracket welded in place for a proper job :roll: Even doing that means removing all my loom clips riveted there and removing the header tank ----- bolted will have to do if it gets done :|

Re: Rocker tower brace

Posted: Thu May 24, 2012 11:39 pm
by pigeondave
Shirley if you weld it in you'll never get the engine out again, as the bell housing is up tight (10mm) against the chassis.

Re: Rocker tower brace

Posted: Fri May 25, 2012 9:06 am
by stylussprinter
pigeondave wrote:Shirley if you weld it in you'll never get the engine out again, as the bell housing is up tight (10mm) against the chassis.
Dave , I think you may be confusing my post about the ''rocker brace'' with CMA's reply regarding the possibilty of fitting a ''bulkhead to tower base'' support :?: If my engine bay was still clear I could have welded that tube in easily ---- basically it would '' mirror '' the driver's side tube that goes from bulkhead / pedal box / tower base / on Stylus's :wink:
Doing this wouldn't prevent engine removal , in fact Tim/ssc did this on his RT and other chassis after that --- BUT it was 'DH2 Dave' who's strengthening mod's on the same lines , started me thinking :roll:

Re: Rocker tower brace

Posted: Fri May 25, 2012 10:14 am
by pigeondave
Ah, Sorry wrong thing.

I know what you're on about as im trying to get one welded in early next week as soon as I can find the right bit of steel.

Re: Rocker tower brace

Posted: Fri May 25, 2012 10:40 am
by stylussprinter
pigeondave wrote:Ah, Sorry wrong thing.

I know what you're on about as im trying to get one welded in early next week as soon as I can find the right bit of steel.
Ideally , a 1.6 mm x 25mm CDS tube Dave ---- if you can't get it locally try metals4you online , they get it to you in a few days and by the metre :wink:

Re: Rocker tower brace

Posted: Fri May 25, 2012 12:15 pm
by pigeondave
I was looking at 1/2" box. Just as the other side from the pedal box.

The Fury and Stylus Chassis are very different. I was looking at MikeB's car the other month and found it interesting to see welded plates and RHS sections in different orientations to the Fury chassis.

Re: Rocker tower brace

Posted: Sun Jun 17, 2012 11:03 am
by stylussprinter
Dave DH2 will be pleased to know that the tower brace I made and fitted , albeit in a different location to his , really changes the car's behavier on turn in , very twitchy with very careful steering input required/less :!: so there's an opportunity to reduce the rake a little for even more rear grip , without inducing understeer :P
This proves that although I thought the towers weren't moving ---- however little , they definately were :wink: This obviously changes the camber but particularly castor during weight transfer/cornering :roll:

Re: Rocker tower brace

Posted: Sun Jun 17, 2012 10:09 pm
by DH2
stylussprinter wrote:Dave DH2 will be pleased to know that the tower brace I made and fitted , albeit in a different location to his , really changes the car's behavier on turn in , very twitchy with very careful steering input required/less :!: so there's an opportunity to reduce the rake a little for even more rear grip , without inducing understeer :P
This proves that although I thought the towers weren't moving ---- however little , they definately were :wink: This obviously changes the camber but particularly castor during weight transfer/cornering :roll:
Sounds like a good mod then. The towers are quite bendy in the fore-aft direction...

Dave

Re: Rocker tower brace

Posted: Sun Jun 17, 2012 11:15 pm
by stylussprinter
DH2 wrote:
stylussprinter wrote:Dave DH2 will be pleased to know that the tower brace I made and fitted , albeit in a different location to his , really changes the car's behavier on turn in , very twitchy with very careful steering input required/less :!: so there's an opportunity to reduce the rake a little for even more rear grip , without inducing understeer :P
This proves that although I thought the towers weren't moving ---- however little , they definately were :wink: This obviously changes the camber but particularly castor during weight transfer/cornering :roll:
Sounds like a good mod then. The towers are quite bendy in the fore-aft direction...

Dave
Dave , from the way the car handled it was pretty clear that the flex in the towers / pre - brace fitting , was a twisting motion-- ie. drivers side clockwise --- passenger side anti clockwise , so increasing castor and neg camber at the same time . With the brace , it now requires more camber and another little tweek to get the balance back. To prove the point , on inspection at home after the event , only half the tread pattern on the outside left front tyre was peeled with heated rubber and before it was equally across the tread :wink:

It just goes to show that learning never stops :)

Re: Rocker tower brace

Posted: Mon Jun 18, 2012 5:59 pm
by DH2
Only applying a small amount of torque to the pivot bolts and whole thing bends - what sort of torque should they be done up to?

Dave

Re: Rocker tower brace

Posted: Mon Jun 18, 2012 7:20 pm
by stylussprinter
DH2 wrote:Only applying a small amount of torque to the pivot bolts and whole thing bends - what sort of torque should they be done up to?

Dave
Not sure which bolts you're refering to Dave :?: Do you mean the rocker bearing nuts ? Mine don't move so perhaps there's a weld fracturing. I haven't measured the torque on those , just pulled them up with as much force as my arm will muster , so likely to be 90 to 100 lbft knowing my heavy hand :roll:

Re: Rocker tower brace

Posted: Mon Jun 18, 2012 10:58 pm
by DH2
stylussprinter wrote:Not sure which bolts you're refering to Dave :?: Do you mean the rocker bearing nuts ? Mine don't move so perhaps there's a weld fracturing. I haven't measured the torque on those , just pulled them up with as much force as my arm will muster , so likely to be 90 to 100 lbft knowing my heavy hand :roll:
Yes the rocker bearing nuts (not bolts, bad me). The rear 'tower' is just a sheet of steel, no strength in it at all. You could argue that it doesn't need it, but it can't do any harm to add some. There is going to be a major welding fracture when I get around to them with my angle grinder!

Dave

Re: Rocker tower brace

Posted: Wed Jun 20, 2012 9:33 am
by stylussprinter
DH2 wrote:
stylussprinter wrote:Not sure which bolts you're refering to Dave :?: Do you mean the rocker bearing nuts ? Mine don't move so perhaps there's a weld fracturing. I haven't measured the torque on those , just pulled them up with as much force as my arm will muster , so likely to be 90 to 100 lbft knowing my heavy hand :roll:
Yes the rocker bearing nuts (not bolts, bad me). The rear 'tower' is just a sheet of steel, no strength in it at all. You could argue that it doesn't need it, but it can't do any harm to add some. There is going to be a major welding fracture when I get around to them with my angle grinder!

Dave
The inner edge of the rear tower flat steel plate on mine has a 15mm's wide strip welded to it from top to bottom which JP obviously intended would stop flex there . Then on cars built by Tim Benbow , instead of only one piece of steel supporting the tower from the chassis --- there are two pieces , one at each side at the top edge back diagonally to the chassis rail towards the bulkhead ---- possibly these chassis towers don't flex :?: If thet were of tube rather than flat , that would stop it :roll: