R&P steering front or back???

[Russ]

I know this has probably been done to death but i thought some fresh ideas might come up.

So what are the pros and cons for front or rear mount R&P.

Also has any wandered around a wreckers with a tape measure to find a rack that is a better fit than the clunka door one, maybe one of the million japo ones

[Rob_FE_56]

  G'day Russ,
I had every intention of running a rear mounted commodore rack in my FE.
It turned out to be a real pita.

The biggest hassle was the tight angle of the top steering knuckle because I intended to run the rack behind the control arm bushes to correct the tie rod/ steering arm angle when steering (Ackerman point radius).

This necessitated a heavily modified sump and firewall (heaps of engine set back) for a holden v8, and made exhaust clearance difficult to say the least.

I reluctantly went to a front mounted rack (NOT C.R.S) and found that the whole setup works better, if done right!

2 little brackets on the front of the crossmember,
a small "scallop" cut out for the pinion and
drop the top of the outrigger down so that the rack sits over the top of it.

It can be made to look very neat, especially when running the exhaust inside the rails.

If you get the geometry right, you can eliminate bump steer, minimise tyre wear and steering lock can be quite good. Some conversions I have seen are terrible in all aspects and really should be re-done.

If anything I think the front mounted rack is easier to set up just using the right combination of factory holden parts.

I will post some pics of mine soon as it should be finished in the next few weeks.

Hr front ends have very ordinary geometry from the factory due to the angles of the top and bottom control arms being so different.

The factory got around this by mounting the tie rod end down inline with the bottom ball joint thus ensuring that the arms could move through the whole range without bump steer.
If you used the hr steering arms with a rear mounted commodore rack you would eliminate this problem but the hr arms are fairly long and you may find that the steering ratio is to low. (300 turns lock to lock)

Cheers, Rob.
(P.S sorry to ramble but I've wasted too many hrs on this not to be interested. Lol.)

[fcguy]

hey guys just my input if you would like it ive got a 58 fc with hrs front end hz discs and calipers bolted to that are the original hr drum steering arms which have the same taper as the commodore tie rod ends and once the rack was shortened properly and fitted i paid $300  from a local engineer to supply and shorten a recon manual steering commodore rack and mount it with cand it turns out with the hr steering arms it has the correct geometry as im not wearing tyres out on the inner or outers i would assume its a great success although as pointed out above i did have to modify the sump of the 308 not muchbout 20 mm from memory just cut and welded ( could be a better job aesthetically but it does the job) and the back of the sump where it tapers straightend a bit to increase capacity from where u lose it then just had to have extractors made to suit any exhaust shop will make u up a set once the motors in the car and they can have itmy local bloke on the gold coast did an excellent job they tuck around the rack and steering shaft and around the starter motor on the otherside they do-not go through the gaurds as my exhaust bloke pointed out its the lazy mans way out (sorry to offend anyone) but the results speak for them self and i only had to outlay $800.00 for the pair fitted a custom pair so u can pay that easy for late model stuff  the only other thing i had to do was put a smaller v8 starter motor in out of a vs 5lt( the bosch mini starter) makes a bit more room in there for the extractors any other info if you want it dont hesitate but i do drive my car to work EVERY day and it drives great

cheers hope this helps

[Ed]

Hey rob

sounds like a rods racks set up?

did you need to fit very tall engine mounts to get sufficient clearance for the steering rod?

Glenn m, fitted a nissan rear mount rack to his yellow ute, there are pics on the forum somehwere.


Cheers

Ed

[Rob_FE_56]

  G'day Ed,
I have got the SM article with the "Rods racks" set up,  it's fairly similar to what I am running.

The combo was worked out by a mate over the course of heaps of rack conversions.

I think (from memory) Rods racks shorten the torana housing to utilise all of the teeth, thus making a better turning circle.
This pushes the pinion further inboard and necessitates the engine sit higher?

The rack I intend to use has the pinion mounted further outboard and has more teeth to begin with so you can mount it up unmodified.
You can easily get your sump down to 10mm (Vic min clearance) from the rack.
This is about 15mm above the cross member.

I will post some pics when I finish putting it together,        I still need some Hr disk brake stubs to finish it off.

I will be running 13" wheels and vented disks, so I reckon there may be a few other guys keen to see how it goes together.

Cheers, Rob.