another drift 340 fixing it AFTER Buxton drift weekend

[mat_91]

hahaha nice one but no power-steering is also a safety thing when drifting in 3rd few inches from a wall hahah

[Chris_C]

If you worried about safety you need non pas, PAS has less lock.

I used to have a conversion kit for a 300, probably still have it somewhere but it'd be on the island if I didn't sell it.

[mat_91]

the system im thinking using will give me more lock not less chris
im hopefully getting a rack for mock up on my spare 340 shell tomorrow and a pump when i get payed next week maybe lines as well depending on price as well
shouldn't be to hard to do after doing some research

[charlieog1243]

and i can now enjoy driving it apart for no power-steering

i moaned about not having power steering then i manned up

[Chris_C]

the system im thinking using will give me more lock not less chris

Cool! Be interesting to have a look.

The other thing I'd worry about is the 360's PAS setup doesn't "auto dial in all the opposite lock you would ever want" as well as a 40 one I found, yet AFAIK the Ackerman is the same on both?? No idea

[mat_91]

it could be to do with camber angle or king pin angle or both the included angle to see why

[foggyjames]

Excellent to see a driveshaft being made...good work. Just one question....why bother with a centre bearing? In theory, you could just use a completely solid prop, assuming the box and engine are perfectly aligned. That's what a 360 has...but the torque tube is there to ensure perfect alignment. In practice, some flexibility is a good idea (to allow for sagged mounts, etc), but a solid prop with a UJ on each end and slide joint at one end would do the job. You only need a centre bearing where articulation for a live axle is required (and possibly to support the weight for a long car. The 2/7/900 series ones are essentially solid from the back of the box to the centre bearing - the two UJs and slide joint are all in the rear section.

cheers

James

[mat_91]

i have been thinking that lately foggyjames when i can get another spare prop or destroy my spare good one
ill have a talk to them about it as it would be cheaper with just two ujs and a sliding joint it would also then just bolt on making it easier to sell on for people

[volvodspec]

difficulty with 340 is the alignment, solid prop will be very hard to get right and without vibrations if you drive, the extra middle bearing makes it a whole lot easyer and more faultproof

the 360's torquetube also has 2 bearings in it, for the same reason.

[foggyjames]

I agree that a solid prop (although theoretically possible) is not a good idea practically, because of the alignment problem. A pair of UJs and a slide joint (or possibly just one UJ and a guibo?) should take care of that side of things. From a quick Google, most of the discussion on the subject I've seen (mainly from kitcar builders, etc) is that even with a body-mounted diff, you still need the UJs and slide joint to take account of engine movement, etc.

As far as I can tell, the vibration aspect is a separate issue. Certainly, alignment is not a problem on a 360. The bearing must be needed for support, so that rigidity and super-precise balancing is less critical (i.e. less unsupported mass to float about in the centre). Given that the original prop was unsupported (although made of aluminium, so lighter), I would be tempted to pursue that option if the driveshaft shop think it will work. You may need to emphasise to them that it's not a live axle - the box is mounted rigidly to the body. In that sense, it's more like the prop for something with IRS (Sierra, BMWs...the list is long). Of course most of those have centre bearings The span for a 340 prop is only similar to that for the rear section of a 2/7/900 prop, though, so I think it's possible.

As you say, a bolt-on solution is so much more attractive than having to add a crossmember for a centre bearing.

Sadly I don't have any spare 340 props. Stick a request in "Demand"?

cheers

James

[mat_91]

thanks for the input guys more to think about, i think a two piece prop would be the best way to go then just weld a straight flat bar across the tunnel then space the centre bearing as needed so could be simple for most people to do

also another tiny update ive just received my spare carb back from a friend which had a working fuel cut off solenoid so chucked that in mine and a clip for the choke control unit as when i removed mine it went flying and i couldn't find it OOPS but its now running the best its ever has and a inaccurate mpg calculations gives around 35mpg 8.07Litres Per 100km so very good to say it has been running rough for most of it

[foggyjames]

It's surely going to cost more to add the centre bearing? You're also in danger of compromising the rust protection (in a part of the car which doesn't really rust) unless you carefully protect it afterwards. It's perfectly possible to protect it properly, but how many people would? I'd issue the most dire of warnings with the kit about protecting it afterwards, as much garages will slap a bit of chassis black on it and call it job done.

I've done a bit more reading, and it seems that swapping a 2-piece prop (in a car with a body-mounted diff) is quite popular in some high performance applications, and that if it's balanced correctly, there should be no vibration issues. The originals are fine, so why should an aftermarket one have a problem? Huskyracer's one from Recoprop was one-piece, too...didn't even have a slide joint.


(http://huskyracer.50megs.com/cgi-bin/i/ ... e/prop.jpg)

cheers

James

[jon-ovlov]

When I was having mine done, we discussed options as for the best way to go. We found in the end a slider and steel prop was a bit too heavy (coupled with them making it unbalanced for me), and it shattered the box casing. We then re-designed it so it was a solid hollow tube, with 2 couplings for box and engine ends (3 parts in total). It was a lot lighter, and ahd it been balanced properly, would have worked fine. (they made one of the couplings off centre, so it never balanced on the car). I'm still waiting for them to come back to me as to what they have now done. That was 4 months ago

NB the prop I had made is good for 250BHP +, which is what I intend to be using around summer time.

[mat_91]

James hadn't thought about rust and like you say volvo used a one piece prop and that works and jon the prop was gunn have the standed volvo joints that was then bolted to the prop. a one piece would be easier and with good alignment shouldnt be problem I may see how much a sliding joint would be. A one piece prop would be easier, cheaper etc just got to wait till ive got the money for it

[foggyjames]

The problem which Anjo was mentioning is that the steel prop they'll make will obviously be heavier than the standard ally one (hence the interest in a centre bearing for support). I take the point, but am tempted to suggest that it will be ok, given that Iain's (Huskyracer) was fine.

I'm pretty sure that Jon's problem was 99% balancing. Iain's (Reco) prop was absolutely fine, without even a slide joint, never mind a centre bearing. I'd be very tempted to have them copy it, personally. The only problem he had with it was that they misunderstood the application, and when he said it was putting 230lbft through it, they suggested that the UJs were nowhere near strong enough for that, and installing driveshaft hoops was probably a good idea Of course if they'd built it to the correct spec, it wouldn't have been a problem.

The other aspect to the slide joint business is that it would be good practice to make sure the engine and box are correctly aligned when static. Chris is convinced that the majority of problems with the standard props are caused by mis-alignment. The engine will move under load, but you can do the whole lot a big favour by getting the static alignment right.

Really pleased to see you taking the lead on this one dude. Hope you don't think I'm being grumpy with my suggestions We should get a meet sorted out with you, matey with the turbo in Mansfield, Adam and Dan, etc. My car's off the road for winter now (combination of wanting to keep it out of the salt, and it needing various repairs), but I can come along in the modern thing, or wait until spring?

cheers

James