Front suspension mods

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pitman
Posts: 7
Joined: Mon Oct 14, 2013 10:29 am

Front suspension mods

Post by pitman » Mon Dec 04, 2017 11:22 am

I own a '65 Tiger that I've pretty much converted to a II (grille, headlamp rims, other aesthetics, and a rebuilt 5-bolt 289 that's on its way with estimated 280HP (from BlueMonkey in the US).

I'm not a speed freak, but I do like good handling, so that's my next focus (so far that's just involved replacing seals). To that end...

What are the pros and cons of the MG Midget steering rack conversion? Most references to it in the forums claim better handling, meanwhile the guys who wrote up 'Taming the Tiger' actually removed it and claimed handling to be fine, if not superior:
https://classicmotorsports.com/project- ... the-tiger/

Also, I checked out Dale's website, but he no longer advertises his conversion kit. In its place is a $4000(!) complete front suspension replacement! Anyone have experience with it? Is any superiority (to the MG or even stock) really just seen on the track?
http://www.dalesresto.com/newsusp.html#content
...and to those who are happy with an MG conversion, does anyone else supply the kits? (I've found the rack itself new on eBay, still going for ~$300:
https://www.ebay.com.au/i/172774286331?chn=ps )

Meanwhile, I've read in numerous places that sway bars aren't necessary. Is this the experience of peeps here? I'm tempted at least to get Dale's stiffer springs mentioned in Taming the Tiger (US$800 for front and rear), and will get the crossmember checked and ?reinforced/?replaced if necessary. Anything else fundamental (or 'easy') I could/should do to improve handling (for street use, not racing)?

meadowhog
Posts: 391
Joined: Fri Dec 16, 2011 1:50 pm
Location: South Bucks

Post by meadowhog » Tue Jan 02, 2018 10:17 pm

Well there’s a lot could be said. The midget rack goes some way to helping Ackerman angle. It’s not THE answer but Dales kit probably is at a price. The steering arms are a little longer but the rack makes steering overall quicker. The drawbacks are the forces needed to turn the wheel and also the turning circle is reduced from poor. Be careful that the rack is not the new cheaply made one and prone to problems. Overall it has been found to be an improvement but doesn’t really help racing.

Increased front spring rate is a must and I’d go for a 7/8” front sway bar. Also shocks are important up front and set to hard while leaving the rear soft.

Depending on your driving style traction bars could be fitted but there are alternatives which would reduce axle tramp.

One thing many of us don’t have but should is an lsd. Definitely recommended by those that have one.

There is of course the most important part wheels and tyres hopefully you’ve managed to find something about that on line. Most people seem to be settling for front 195/50/15 and rear 205/50/15. I’ve managed 225 rear on 8” rim.

With the larger wheels you can fit larger Peugeot vented discs and Brembo callipers. This is a common upgrade.

FWY896C
Posts: 16
Joined: Mon Nov 28, 2005 12:03 am

Post by FWY896C » Fri Jan 19, 2018 2:40 am

After driving a Tiger fitted with the Midget Rack and PAS this is the set up I’ve gone for on my Tiger when it’s finished. The steering is a lot quicker with the Midget Rack BUT the steering is really heavy without a PAS set up, a lot heavier than standard in my opinion. A guy who has been a tremendous help to me while restoring my Tiger is Stuart. He can help you out with any advice or parts you need to carry out this conversion. His website is here.
1965 Sunbeam Tiger Mk1

Pierre
Posts: 37
Joined: Tue Aug 27, 2013 4:37 pm
Location: Very near Silverstone

Post by Pierre » Fri Jan 19, 2018 9:46 pm

My Tiger has some re-worked front suspension/steering mods.

I understand it was fitted with an MGB rack well before my ownership but I cannot any more on this mod.

The tie-rods were replaced with a cranked version supposedly to provide an anti Ackerman effect, not sure about this as I hear tyre scrub on full lock.

The upper wishbone fulcrum pin was slightly inclined down to the rear which theoretically raises the roll centre and reduces nose dive under braking. It has been shimmed to provide negative camber; this resulted in very heavy steering which was overcome when Jim Oven installed an electronic power assist.

Front springs were changed to give a 50% increase in spring rate, Konis were added together with a 24mm anti-roll bar.

Together with some mods to the rear suspension set up, achieved an overall reduction of 1.25 inches in ride height.

The result of these mods is an easily steered car, albeit with limited feed-back through the steering wheel.

Cornering is amazing and throwing it into a roundabout at speed is only limited by my nervousness.

When next in Boots I must ask for some brave pills. :oops:

Good luck with your car.

Best regards,

P
289 Hi-Po driven by Carroll Shelby at Le Mans in 1994
Benelli 750 Sei
Delica LWB - project vehicle

bigbob
Posts: 371
Joined: Wed Aug 19, 2009 11:31 am

Post by bigbob » Tue Jan 23, 2018 6:17 pm

I have all similar mods to Pierre. Power steering with the MG rack transforms car. Also power assistance is variable so you be adjusted easily to suit your taste. 15" wheels and discs all round cope well with modern driving. 5 speed gearbox also a great improvement.

Pierre
Posts: 37
Joined: Tue Aug 27, 2013 4:37 pm
Location: Very near Silverstone

Post by Pierre » Tue Jan 23, 2018 7:20 pm

No rear disc brakes but a larger servo (located under the rear seat) pulls my Tiger up with plenty of smoking rubber if brake pedal is pressed too hard!
Love to have a 5 speeder but overspend on house renovations put paid to that. Will be having a big clear out soon via eBay so hopefully may get a few pennies to fund the 5 speed project.
Regards to all.
289 Hi-Po driven by Carroll Shelby at Le Mans in 1994
Benelli 750 Sei
Delica LWB - project vehicle

Russtee
Posts: 12
Joined: Wed Mar 12, 2014 3:47 am
Location: Tauranga New Zealand

Post by Russtee » Sun Feb 11, 2018 1:20 am

Pitman...I have just taken out of my Tiger the MG Midget rack that used Dales conversion brackets/tie rod extenders. I've left the MGB longer steering arms in place and fitted one of the new UK re-make Tiger racks made by the Birmingham outfit.

Overall imho the driving experience with the Midget rack...is heavy, gives too much feedback thro the rack with its much reduced ratio, adds to the turning circle, although not that critical.

The hassles for rhd cars is that the Midget rack pinion does not sit in the same place as a std Tiger rack, its shorter and there is the radiator elbow that gets in the way. The universals on the Tiger steering are the same as Jaguars and are beefy and there is reduced wiggle room.

Because the rack arms are straight they get pulled back even with the longer MGB steering arms out of their best working position, i.e. the rack end ball joint looses about 25% of its travel as its not in the 12-6 o'clock virtical plane. This means there is considerable wheel toe-in created when the front suspension is raised off the ground...the rack ball joints simply run out of travel before the suspension reaches its lowest point...ok for a road car but would be havoc in a race car that lifted the front under hard acceleration. The std Tiger rack fixed this problem by bending the rack arms but created worse problems of the ackerman angle and no exact toe-in adjustment. Back 30 years we used a 4/44 rack in our race car...it has a longer pinion which we shortened to a good workable length, same spline and the rack arms are longer than a Midget but still require lengthening. We did this by lengthening the tie rod ball joint barrel and then we bent the arms ala std Tiger.

My conclusion: use an MG rack if there is no alternative or a quicker ratio is wanted and your budget is tight. Local car has a Subaru power steering rack and I like this better. Dales complete front end with brakes is U$6200...I would buy in a heartbeat if I drove my car alot more than I do these days and could justify the cost. My car runs a Toyota W55 5 speed with 3.07 diff and this conversion makes city and hill driving a breeze.

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