How much is too much?

[slobbo]

How many ponies do you think a Syncro box could handle. I have 2.9 VR6 in mine which produces about 190bhp And 140ft-lb of torque @ 4200rpm. The box in have is the 2.1 variety. The clutch is a standard 2.1 clutch. It all goes well but I I don't often push it to its limits. How much more do you think the box could handle?

[..lee..]

Aidans you`re man but i`m sure i heard 300nm talks max. i`m currently running about 26nm of talks so my box`s warranty is uneffected.

[slobbo]

Not planning anything just curious. Couldn't afford a turbo and cooler just now. Got a few other things to pay for first.

[HarryMann]

220 ft-lb on a good day? The nature of the torque spikes (diesel or multi-cylinder petrol) may have some bearing

[Aidan]

VW rated the box at 200Nm with the oiling plates with the standard gears, new
The heavy duty gears are rated at 300Nm but the crown and pinion, ie the really expensive to replace bit is still only 200Nm
now given that most ratings include a 50% headroom as probably destruction tested at double that I have been prepared to take the risk under warranty for 12 months on anything that anyone has done so far.
But on the basis that the majority of components are 20+ years old and of unknown provenance (recent gearbox with bent pinion shaft for example) you'd be asking for trouble if you push the envelope too far
I've had people kill the box because they bump start them, because they have no mechanical sympathy and no ears or because their VC is tight but they don't know it, but so far noone has killed one with power or torque alone
However now my stash of crown and pinions is pretty much depleted either I'll have to start to factor in a safety margin financially to cover the cost of replacement crown and pinions ($1360 plus shipping and taxes) or start limiting the warranty somehow

Personally I don't get the 'need for power/speed' thing, just use them as they were built they are just fine, if you want a car for hooning then buy a MR2 and go trackdaying, the public highway is not the place to push the envelope imho, there's more than enough complete f'ing numpties out there already and they are breeding

Or build a rally bus a la Yager and rally it if you want to find out just how far a T3 syncro can go

[slobbo]

Cheers Aidan. Was just curious. One of my mates is a boy racer
And tunes vr6s. He reckons I should turbo it. I keep telling him it is fast enough and it goes the speed limit so why go to something that would stuff the gearbox.

I can see the need to tdi as the diesels are well rubbish. Why put an engine in something that can't maintain the speed limit on even a slight incline. Big fail by VW. 2.1 boxers seem capable enough. Had one briefly and it was lovely to drive.

[HarryMann]

Turbo'ed petrols can be 'orrible things, and v.juicy with it: if I won the lottery, it would be a MClaren F1, because it's naturally aspirated (and still probably the most expensive of all in the used supercar market)

http://www.supercars.net/cars/1177.html

[silverbullet]

220 ft-lb on a good day? The nature of the torque spikes (diesel or multi-cylinder petrol) may have some bearing

It's all about the nature of the torque delivery afaics i.e. avoiding very low-speed/high-load conditions at the gear contact faces, when the lubrication films break down and scuffing/tooth overloading results.

An overloaded camper (pushing the 1-ton payload limit) with a lot of low-speed torque, driven up a steep incline in G gear is going to give the diff a very hard time in this regard!

I reckon that there is also a fundamental design flaw with the T3 transaxle unit: in so much as when in forward drive, the rotating crownwheel draws oil away from the pinion and it's bearing...in a front-engined non-transverse vehicle, the crownwheel pushes oil toward the pinion.

This would contribute to pinion bearing overheating and failure. Red herring or valid observation?

[HarryMann]

Afraid I can't visualise that Ian, but I think it could be a red herring... its possible (and not an uncmmon practice) that a transparent (or windowed) casing was made up to visualise the oil flows and lubrication splash paths, during Design and Development

[Aidan]

totally valid - that's why the VW came up with the oiling plates, one collects the oil spray off the roof of the box and drops it down onto the pinion head, also helps cool the oil slightly through heatsinking to the case which is finned for cooling as well as strength with lightness, oil temp reduction of 20degrees C reported in hot climes with the oiling plates
mostly due to better lubrication of the c and p

[silverbullet]

its possible (and not an uncmmon practice) that a transparent (or windowed) casing was made up to visualise the oil flows and lubrication splash paths, during Design and Development

Funnily enough I had made noises to Aidan about doing just that with a near-dead undesireable 2wd trans!

Something else that I recall from RR days. Note all of first paragraph! (but this was for V8's and VM 2.5 Turbo D, both with 135 bhp and over 200 Lb.ft)



Alternative aftermarket version:

[Macflai]

Alternative aftermarket version:

Jezzz!! This aftermarket version had me laughing for a while!!

Who made it? Would like to have one!!

[silverbullet]

totally valid - that's why the VW came up with the oiling plates, one collects the oil spray off the roof of the box and drops it down onto the pinion head, also helps cool the oil slightly through heatsinking to the case which is finned for cooling as well as strength with lightness, oil temp reduction of 20degrees C reported in hot climes with the oiling plates
mostly due to better lubrication of the c and p

Funny thing is I've never thought about exactly where they go, or even seen a picture of them mounted in a casing.

Would like to see one though!

[HarryMann]

Alternative aftermarket version:

Some funny quoting going on here

[silverbullet]

For our Solihull Shed fans

http://stores.ebay.co.uk/Green-Oval-Landrover/Badges" onclick="window.open(this.href);return false;