'betsy' 3500 hot rod project

i dont think you would replace the whole body with tube chassis althought i suspect that would be more than possible the easiest way would simply be to remove the floor pan and build i tube chassis into that space with uprights for the suspension, i also feel that this idea whilst being a really good one from the drag racing point of view will have to be quite low on the list of priorities as would be far out side my budget and only really useful once i get the engine upto a very high level of power output
 
I'm assuming you're planning on using something like a salisbury axle from a mk11 jag. Couldn't you 5 link the axle in place using or adapting the existing mounting points? Looking at the size of the elbows and the positioning of the leading and trailing links on the elbows, to me the dimensions look ideal to build an almost bolt in 5 link set-up. You could either use the original spring & damper positions on reinforced lower arms, or build turrets into the inner wheelarch area and use coilovers. The fuel tank would possibly need to be removed, and a new crossmember fabricated in place of the crossmember that originally holds the rear of the drive unit, but with a large bowed section in the centre to clear the differential at full compression.

That's what I'd be doing if I was fitting a rear live axle to a p6.
 
It's no good, I can't resist and I know I'm going to regret this. Why would you want to fit a live axle to a P6? I realise this a drag racing thing, so I shan't even try to whinge on about the handling advantages of a de dion. But surely the de dion is even better than a live axle at putting power down off the line! And surely that must be what drag racing axles are all about? Certainly well superior in this respect than, say, a BMW style rear end. The only other motivation I can think of is the easy ability to upgrade an axle to another capable of better torque handling. But the diff in the P6 is bomb proof, and I would have thought the 4 pot ratio combined with the V8 planet wheel set up would give a suitable ratio and strength. Before anybody says anything, yes the P6 drivetrain has two problem areas, scewing up the diff input shaft and screwing up the diff output flanges. The former has an off the shelf available solution in better material and it wouldn't be difficult to do the same for the output flange.

For my money I'd count the de dion as an advantage on a drag strip, not something to junk.

I'll sit back now and wait to be educated!

Chris
 
I actually agree with you that the de dion is a great set up and if the plan was to go jut suped up muscle car for general enjoyment i would never consider the live axle. and the only point we would consider going to the extreme of liv axle would be once the power gains start getting too much for the wheels to deal with, the main reasons for possible change to live axle would be because of the limits of the diff and the ability of the jag axle to be shortened to allow much wider wheels without upsetting the lines of the car.
The eventual plan with the car (and this is far in the future) is for the engine to be force fed with a weiland supercharger combined with twin 4bbl holleys and then a small amount of NOS once i start getting into that scale of power then the live axle might be an option at the moment the only thing would be to change to stickier tyres
 
chrisyork said:
But the diff in the P6 is bomb proof, and I would have thought the 4 pot ratio combined with the V8 planet wheel set up would give a suitable ratio and strength. Before anybody says anything, yes the P6 drivetrain has two problem areas, scewing up the diff input shaft and screwing up the diff output flanges. The former has an off the shelf available solution in better material and it wouldn't be difficult to do the same for the output flange.

Chris
Click to expand...

:shock: True the outputshafts and pinion shaft have their fair share of the breakages, but I've had plenty where the diff gears have grenaded themselves and had to be washed out of the casing. The crownwheel and pinion seem to be a bit better though, but still all in all a very waek diff, which "sowen" seems to have made a pretty good job of curing once and for all.
 
Another consideration that is often overlooked is the costs involved with re-working the rover drive unit to handle extra loads. I've read about the up-rated input shafts and output flanges, but can't imagine them to be cheap, then the weak point is transferred to the pinion gears in the differential as harveyp6 says, leading to potentially more costs and uncertainty to the reliability of the drive unit as a whole.

As Sharonandmatt have already indicated they have a possible source of axle narrowing services, then the live axle is definately a route worth following if at all possible. I've been doing some research and found that the original factory p6 racer used a jaguar differential and the rest was a reinforced rover de dion setup, so if you're intending on keeping everything as close to period correct, then either way the jaguar route is worthy of consideration.

Another point of consideration is that if the top trailing links are relocated to inside the line of the chassis legs, then you will have more room for wider tyres in the rear without the need for tricky body mods. Utilising a live rear axle, you will not have the problem of the track changing while the suspension works, so allowing a better axle/wheel/tyre combo being chosen that will only move vertically as such, and not in addition latterally with the de dion axle (if that makes sense).
 
that makes perfect sense thanks! well lots to plan and pay for i suppose but i definitely think the live axle will happen some point next year its the only way to sensibly gain wide tyre and a reliable diff without ridiculous modifications to the exterior
 
You must log in or register to reply here.
Back
Top