Newbie, Fiat TC & Volumex HFO 501 NEW BUILD 2018

[fixwheelmad]

What about the 5th bar to keep the axle central to the body?
If you intend to retain the leaf springs you only need the two bars to eliminate axle tramp.

Phil is this for Nourish?
I’m running 4 bar and pan hard link, coil over shocks in new towers. Leaf springs/tramp bars are ok up to a certain Bhp or driving style, beyond that the windup from springs and link joint is awful. IMHO

[philthehill]

Yes it was meant for Nourish.

I have got 7 leaf springs reduced to 6 leaves, re-set to lower by 2". Rose jointed traction bars fitted and 7J wheels and slicks. Never had any problem trying to get and keep the power down. I once had a Panhard rod fitted but found little if any improvement. Watts linkage is the way to go if you do not want any side movement of the axle relative to the body.
Phil

[Nourish]

Ah - of course - panhard rod or watts linkage will be needed.
I was thinking of using coilovers so towers, floor panels and bracketry will have to be fabricated.
Adrian(Morrisfixer) had done this on the other side -
https://www.morrisminorowners.co.uk/vie ... &start=405.
He's used an Escort kit with Classic Mini Coilovers. So I've studied his and as many other pictures I could find but it does not explain the why's and where's - Dimensions are nice.
I was thinking of rose joints on the axle and silicon buses on the body fixings as per Adrian.
Shock length - it was always said that the mini shocks were to short when set up as like the van/pickup/LCV but then they are upright and he says they work.
Setting up? these are some of my thoughts/dilemmas
Towers - I imagine the height of these will be set with the axle at full lift and the shocks compressed. The towers as close to the chassis boxing) as possible and fixed also to the reinforced inner wing and braced between the two.
Shocks/Springs - adjustable - Length and rates?
Link Boxes - should these run parallel or splayed - thickness of material? placement dimensions?
Link Bars - Bush ends to be wrapped - CDS tubing - diameter and wall thickness? Which rose joints and bushes to use (size&quality)?
Assume link bars should run parallel (top and bottom per side) to each other and parallel to the ground at rest?.

Cheers

[philthehill]

The problem I had when initially converting my Minor for competing in speed hill climbs in the Modified Production Class up to 1400cc was that the rules stated nothing was to encroach into the passenger compartment or any alterations to the floor pan between wheel centres were to be made.
This ruled out having the four link rods in tunnels which rose above the original floor pan.
The axle currently fitted to my Minor has the brackets for the four link and Panhard rod. It was originally fitted to Carl Talbots comp minor which fell foul of the floor pan rule. He replaced the Minor axle with a Ford axle which had the top links attached to to the outer face of the wheel arch. He was producing twice as much power as me and needed the five link set up. Even with the five link set up he could not get the power down onto the ground so gave up using the Minor. He transplanted the engine into a Lotus Seven and started winning. So the moral of this story is no matter what you do to improve the Minor suspension it is very hard to get the power down onto the road within the comp rules.
I am in the process of updating the anti tramp bars with rods/links and rose joints from McGill Motorsport. The rods are available in various lengths to suit and threads. www.mcgillmotorsport.com. I have purchased several items from them, they are very helpful with a quick delivery.
These are the ones I have used for the anti tramp bars https://www.ebay.co.uk/itm/161296129695
Phil

[fixwheelmad]

Today was good and hard, managed to get axle, tie bars and shocks in position, pan hard might change position.
Issues spacing, measurement from bench to car differed! God knows why, spent about three hours moving axle and brackets back n forth.
So 4 bar lengths not checked, rookie mistake, front edge of bar position parallel to rear face of diff.
The issues now are shock positions, and the brackets to enable eyelet to pin to changed, fortunately AVO can modify my shocks to pin in service.
Still not convinced with panhard final position so going to leave after shock rebuild 2 weeks, new brackets tomorrow and final set up 3 weeks. But still a good step forward.

[fixwheelmad]

Images

[fixwheelmad]

Going to make some adjustable top mounts, need to see if vertical position of shock can be adjusted. Other than than very happy, ordered the CDS for rear roll cage and will crack on, very pleased....
Dims and info
Shocks 300x300mm to eyelets, 4” of travel 180lbs 2.25inch dia springs, need service and conversation to top pin.
All bushes are poly bush (race spec) M12 bolts throughout!
Axle travel without springs 4” from Center line to top out.
Will be running 300-400lbs springs on the front 1.9 inch dia to start, might go harder, have 50lbs increments to 600lbs.
Adjustability within 4 bar link and panhard 25mm in any direction, within shock height 3-4inch
Essentially need to have a system that suits you and setup.

[Nourish]

Excellent pictures - thank you.
Some questions if I may - You've set the axle brackets on the same plain as the diff face - have you aligned the diff to the gearbox output shaft?
Are the l/h bars running parallel to the r/h ones?
What have you chosen for your ride height?
Looking forward to the next up date.
Cheers
Martin

[fixwheelmad]

Excellent pictures - thank you.
Some questions if I may - You've set the axle brackets on the same plain as the diff face - have you aligned the diff to the gearbox output shaft?
Are the l/h bars running parallel to the r/h ones?
What have you chosen for your ride height?
Looking forward to the next up date.
Cheers
Martin

Ride height will be sorted under final weight, I will have 4 ‘’ full travel, as shock are fully adjustable I will estimate position from bump stop and work back.
I was going to use a ally single prop that needs glueing and riveting, much lighter that a two piece, but heard tale of sonic resonance so a little concerned, also alignment must be spot on.
So will use my fiat two piece and ford UJ, still will need shortening I feel, will see.
Link arms as said are adjustable, I have 6 holes at the front and two at the back , so each bar has 3/2 position options especially trying to achieve best or optimum anti squat, that enable power to be put down.

I trust you have this book: https://www.amazon.co.uk/Chassis-Engine ... 1557880557

It clearly shows 4 bar setup, rolling action and forward inertia position of car, also looks at other side bracing options Watts etc, very good book if only to under standing suspension geometry.

[fixwheelmad]

Phil, thanks for that link to McGill. Spot on, wish I’d seen that first! All about learning .....made my day, off to do shopping list and cain the VISA!

[Nourish]

Chassis Engineering - a copy ordered - thank you.
Also you've said that your rear shocks are 300 - 300mm between centres - is that why they need a rebuild?

Phil, those bars you've ordered - 16mm diameter - not very big are they - big enough for a 170bhp 4 bar link?
I took a look at Rally Design's site and must admit that for £120(+vat&P&P) for the two boxes, brackets, 4 link bars with spherical joints and bushes doesn't seem to bad.
https://www.rallydesign.co.uk/product_i ... ts_id=4298

[philthehill]

The rod ends to be used are 1/2" UNF which are one size up on the 3/8" UNF currently fitted & which have easily coped with 135 bhp plus and many many standing starts at high throttle/revs.
Split that 170 bhp into four and each rod only has to cope with 42.5 bhp.
The two 3/8" bars at 135 bhp only have to cope with 67.5 bhp each and cope they do.
The only reason I am changing the bars is that way back you had to make everything from what you had and there was no 'e' bay. Purchases had to go the long way round. Now I can get things off the shelf and CNC made.
Phil

[Nourish]

On your car Phil aren't these rods supplementing the leaf springs?
I certainly wouldn't question the ability for the rose joints to cope but question the rigidity of the tubing used.
Cheers

[philthehill]

The anti-tramp bars fitted to my car control a flexible leaf spring. The leaf spring is not a substitute for a traction control rod as a complete set of different parameter's effect and control a leaf spring.
The rigidity of the home produced box section traction control tubes has worked well for the last 40 years.
The traction control bar is only required to control the fore and aft rotary motion of the rear axle so it does not have to be that rigid or of a large diameter. Bigger is not always better.

[Nourish]

You lost me there!

[fixwheelmad]

Chassis Engineering - a copy ordered - thank you.
Also you've said that your rear shocks are 300 - 300mm between centres - is that why they need a rebuild?

Phil, those bars you've ordered - 16mm diameter - not very big are they - big enough for a 170bhp 4 bar link?
I took a look at Rally Design's site and must admit that for £120(+vat&P&P) for the two boxes, brackets, 4 link bars with spherical joints and bushes doesn't seem to bad.
https://www.rallydesign.co.uk/product_i ... ts_id=4298

Nope they were off another build , and I have a box of coil springs (180-600lbs both 1.9 and 2.25inch dia) and like the fact that AVO are UK and can replace adjust or upgrade any shock they make, the trick is to mix and match until the weight and ride height all works, then there's the dark art of corner weighting!

And as Phil said bigger aint always better......

[Nourish]

Have you missed the point - they can't be 300 - 300mm between centres - more like 300 - 400mm?

[fixwheelmad]

This week has been interesting, there’s a few questions and I’d value some feedback. Made test for the door pulls, thanks to JB for the original drawings and feedback on steering info. Was good to catchup with him.
So first images door pull, out of solid stock and in need of shaving weight, drilling out.
So the main issue were concluding the base stock position of the front shock on the rear torsion arm.
Issues (read from somewhere) that the coil over must be near to vertical or at least with 10-20% to maintain efficiency however what about the eyelet position and lineament ?
If the shock is pin at the top does not know where it is?
I have concerns about the restrictive nature of the eyelet swivel is routed 90%, the old design was far too weak and messy, so I made up some options.
Finally settled for the eyelet in line, which meant I had to build a box and slot into the arm.
The best position would be across both arm, however that would mean I’d have to remove my top brackets, and they good and bombproof.
Finished late last night only because I want it finished.
Mock-up is on left side, finished article is the drivers side. Need to strip down the left side and repeat, if all good that’s the front done.

[fixwheelmad]

Front bottom shock mounts testing and mock up option one

Clearly seen on image two, my concerns about the swivels at 90% opposed, even with my wedge spacers, they will max out hence concern.

[fixwheelmad]

Option two and preferred one, for now......