Stronger driveshafts?

[TomCresswell]

Hi, just reading around (for my M62 swap) I just saw a few comments about wanting stronger driveshafts.

Not sure if it's of interest but my company makes aerospace steel driveshafts for 2 of the top F1 teams and many other applications from rally cars, time attack Evo's, clubman racers to your young sprout with a 300 brake Renault 5.

Just putting this here to see if it's of interest, we can make a 1 off, 6 off, 100 off whatever and they're not stupid money and they don't snap. A group buy could work out to be very cost effective.

Check out www.glebe.co.uk for more info

While I'm at it we do flywheels, ring gears, hubs, gears, spacers, racks and pinions and get involved in all sorts of weird stuff... 1 off Spitfire parts from a sample found buried in a field etc etc.

This isn't a 'sell' as such, just an introduction because I happened to read about broken driveshafts. Our core business is oil and gas, pharmaceutical and F1 and we do clubman Motorsport/road car stuff very reasonably, mostly because it's mine and my families main interest!

If there are any other E30 problems that might be solved with a good machine shop that deals with fabrication and heat treatments, coating etc then suggest away. I'll be here in the background reading/worrying about wiring my 325i with the 740i auto donor I've just bought.

Regards,

Tom

[appletree]

Make some 5 stud e30 hubs that fit the 4 stud cars not adaptors but proper hubs made to be 5 stud.

[ross_jsy]

What appletree said. That would be great.

How much would driveshafts come in at?

[TomCresswell]

Make some 5 stud e30 hubs that fit the 4 stud cars not adaptors but proper hubs made to be 5 stud.

EXACT copies of E30 hubs but with a 5 stud bolt pattern?

[TomCresswell]

What appletree said. That would be great.

How much would driveshafts come in at?

For one pair, too much. The heat treatment for this particular material is on a minimum order schedule so it costs exactly the same to heat treat 2 off as it does 20 off. If a few people show an interest I'll quote on here. At about 6 off parts the numbers start to make sense. Don't want to quote you for a pair and put an off-putting and irrelevant figure into circulation. Hope you understand and don't think I'm avoiding your question. I'll PM you the price if there is a demand, so you don't miss it.

Thanks,

Tom.

[faissalo]

A way way better use of your skills would be faster steering racks that are a direct bolt in swap for the standard E30 racks.

Should be laughably easy for a set up like yours. And more people would go for those than 5 Stud hubs.

[craigieeb]

Or even........1 piece propshafts that are adjustable
So it fits all conversion applications

[ross_jsy]

Make some 5 stud e30 hubs that fit the 4 stud cars not adaptors but proper hubs made to be 5 stud.

EXACT copies of E30 hubs but with a 5 stud bolt pattern?

Yes, the current solution isn't exactly ideal.

Don't think there would be much of a market for a faster rack though when e36/e46/z3 solutions are cheap and easy to do.

DSS shafts are popular with the American drag racing/big power scene. Potentially get a lot of interest on American sites like bimmerforums?

http://www.driveshaftshop.com/import-ax ... t-in-axles

[TomCresswell]

All very doable. I was going to put the E46 rack on mine but before I do that I'll strip mine and see if there's anything particularly complicated (expensive) in the design. Shouldn't be, we've done tons of quick racks over the years. We'd do this on an exchange basis, you send me your rack and I send you one back, new rack and pinion, new bushes, rebuilt and powder coated, like new, greased and ready to fit. That's obviously going to cost a few hundred so in terms of cost/time doing a conversion what am I up against for say, an E46 conversion?

5 stud hubs also easy. (Forgive my ignorance, I thought people go 5 stud for bigger brakes, in which case don't you got a 5 stud front end with brakes etc anyway?)

[Grrrmachine]

People go 5-stud for lots of reasons, but the only method that retains E30 geometry uses very expensive M3 (E30 or E36) parts.

5-stud hubs that fit E30 bearings would be extremely lucrative.

[faissalo]

All very doable. I was going to put the E46 rack on mine but before I do that I'll strip mine and see if there's anything particularly complicated (expensive) in the design. Shouldn't be, we've done tons of quick racks over the years. We'd do this on an exchange basis, you send me your rack and I send you one back, new rack and pinion, new bushes, rebuilt and powder coated, like new, greased and ready to fit. That's obviously going to cost a few hundred so in terms of cost/time doing a conversion what am I up against for say, an E46 conversion?

5 stud hubs also easy. (Forgive my ignorance, I thought people go 5 stud for bigger brakes, in which case don't you got a 5 stud front end with brakes etc anyway?)

The E36 / E46 swap is a bodge. Need to modify hoses, modify UJ which loses the steering damper (which I think like) and then there's all the aggro of spacing them up or down in the subframe - get parts of this wrong and you get bump steer. I'd pay unto £500 for a drop in fast rack. I don;t even think you'd need to finish it to the level you;re talking about - just a new rack and pinion wheel fitted into the rack housing ready to go.

The 5 Stud is sought after - personally I'm not bothered as it just opens up a world of horrible, oversized, too wide wheels. Best to knock that on the head.

[daimlerman]

BMW are very good at having 'NLA' service items re-manufactured....but....the price then becomes eye-watering!

A while back brake back plates were on world-wide back order,and an £8ish part became a £40+ part.
So a 'fill in' type offer on that sort of service part would be very helpful.

There was a guy the other week struggling to find a new rear quarter for his bodyshop guy,is that sort of thing within your skill set?

But a straight swap faster steering rack,at a sensible price,say about double GSF's price for a standard item or about £250/£350ish,will find buyers.

[Demlotcrew]

Biggest issue with the racks is the physical size of the rack casing on the E30, its just not able to safely accept the coarser pinion ratio needed for a faster rack, but that was a while back when I looked in to it, it might be that more can be done with more time and testing.

[TomCresswell]

Biggest issue with the racks is the physical size of the rack casing on the E30, its just not able to safely accept the coarser pinion ratio needed for a faster rack, but that was a while back when I looked in to it, it might be that more can be done with more time and testing.

Thanks for the info. I'll look into the options.

Tom

[Demlotcrew]

The very early Half steel power racks are probably your best bet, I gave up as anything I could find was proving to be costly and no real scale for sensible production runs as the ratio is one thing, valving the units for perfect feel was something entirely different

[Motorhole]

+1 for the 5-stud hubs/bearings. Plenty market demand for that.

Opens up a whole new world of affordable bolt-on brake upgrades using OEM discs/calipers with adapter brackets. And would appease all these dudes looking for quick and easy 5-stud swaps.

[TomCresswell]

BMW are very good at having 'NLA' service items re-manufactured....but....the price then becomes eye-watering!

A while back brake back plates were on world-wide back order,and an £8ish part became a £40+ part.
So a 'fill in' type offer on that sort of service part would be very helpful.

There was a guy the other week struggling to find a new rear quarter for his bodyshop guy,is that sort of thing within your skill set?

But a straight swap faster steering rack,at a sensible price,say about double GSF's price for a standard item or about £250/£350ish,will find buyers.

thanks for the info. body parts or pressed parts not our bag unfortunately. thanks for the suggestion though

Tom

[ross_jsy]

All very doable. I was going to put the E46 rack on mine but before I do that I'll strip mine and see if there's anything particularly complicated (expensive) in the design. Shouldn't be, we've done tons of quick racks over the years. We'd do this on an exchange basis, you send me your rack and I send you one back, new rack and pinion, new bushes, rebuilt and powder coated, like new, greased and ready to fit. That's obviously going to cost a few hundred so in terms of cost/time doing a conversion what am I up against for say, an E46 conversion?

5 stud hubs also easy. (Forgive my ignorance, I thought people go 5 stud for bigger brakes, in which case don't you got a 5 stud front end with brakes etc anyway?)

The E36 / E46 swap is a bodge. Need to modify hoses, modify UJ which loses the steering damper (which I think like) and then there's all the aggro of spacing them up or down in the subframe - get parts of this wrong and you get bump steer. I'd pay unto £500 for a drop in fast rack. I don;t even think you'd need to finish it to the level you;re talking about - just a new rack and pinion wheel fitted into the rack housing ready to go.

The 5 Stud is sought after - personally I'm not bothered as it just opens up a world of horrible, oversized, too wide wheels. Best to knock that on the head.

The e46 rack isn't a bodge by any means. Dan provides very high quality conversion pipes or you can bend e30 ones if you must have it OEM. If putting 2 machined spacers in is hassle, then swapping a rack must be an impossibility! And again, if you can't read guides on where the spacers sit and install them that way, you probably shouldn't be working on a car in the first place.

Best not knock the 5 stud on the head either, a lot of us want 5 stud for reasons other than large wheels.

[TomCresswell]

The 5 stud is a definite goer. I don't really want to make my car immobile while I measure. Anyone got any loose they can send me a front and rear hub to measure and in exchange the lender gets their hubs back and a set of 5 stud ones extremely cheap?

[sag]

+1 on drive shafts. Can you Pm with a approx price with or without groupbuy price and what power they can take.

[TomCresswell]

I'll do a proper costing exercise tomorrow and put some guides on here.

Would people be after complete units built up with new joints, boots and CV's or bare shafts?

[ross_jsy]

A price for both would be great. Something like the DSS shafts with high quality CV's would be good too

[TomCresswell]

Ok. Will quote for bare shafts tomorrow and work on the full supply option and get back to you.

Quoting horsepower ratings is fairly useless, it's torque that matters and that all comes down to application (600Nm engine torque on road tyres being a totally different thing to 600Nm on 12" wide drag slicks) I could quote a figure (a meaningless to most of us- per shaft mechanical torque limit) or just tell you that in the history of us making these shafts only one has ever snapped and that was in a MK2 Escort Irish Tarmac rally car that whapped a kerb at 80. This material in its heat treated form has twice the tensile strength of standard high tensile driveshaft material. Helicopter stuff. When we supply a pair of these we offer a free annual magnetic particle crack test and in 15 years no one has ever taken us up on it.

If anyone was at Race Retro the other week and saw the 5.0L Chevy engined Firenza? That car has been snapping shafts (you'll have seen the stick he gives it!), that's now got these shafts in and the problem's gone.

Thanks

[ross_jsy]

While you are at it, some centre lock hubs for true heroes wouldn't be too hard

Looking forward to seeing how this pans out. Can you make one piece props? Although a 1 piece that length is going to run into problems with harmonics

[TomCresswell]

Right £450 a pair for shafts. That's splined shafts with no cv's or boots. Am working on the full bolt on supply option at the minute.

Ignore group buying or any of that complication. I can make a batch and stock them. That's the material and heat treatment I spoke about with shot peening and crack testing and a free annual crack test, to full F1 spec for £450 a pair.

[Owenf]

+1 on the 5 stud hubs

[Motorhole]

The 5 stud is a definite goer. I don't really want to make my car immobile while I measure. Anyone got any loose they can send me a front and rear hub to measure and in exchange the lender gets their hubs back and a set of 5 stud ones extremely cheap?

Unfortunately I can't help with this (already running 5-stud). I do have a spare 5-stud front hub if you need the PCD, thread size etc if that's any use.

[DanThe]

Got plenty of old scrap here Tom if you want to borrow a strut/hub/bearing assembly

[etouring]

The 5 stud is a definite goer. I don't really want to make my car immobile while I measure. Anyone got any loose they can send me a front and rear hub to measure and in exchange the lender gets their hubs back and a set of 5 stud ones extremely cheap?

+1 for 5 stud hubs pm me a price for the drive shafts

[andrew_baran]

Stronger driveshafts sound good. But I thought it was the CV's that are the weak point on the BMW shafts?

I have a small bet on with a friend on how long it'll take to destroy one once my car is on the road!

[ross_jsy]

They will need a stronger CV to go with them as the standard ones have a habit of grenading, particularly on drag launches

[needanlsd]

How about designing shafts to use porsche 911 sized cv joints?
With adapters for the diff flanges etc...

[TomCresswell]

How about designing shafts to use porsche 911 sized cv joints?
With adapters for the diff flanges etc...

This is exactly what I'm working on.

Tom

[M3SAM]

Hi there Tom,

After just snapping another reconditioned half shaft last night!!!!

I would be very very interested in a complete solution as my car with a s54 supercharged putting down 550 WHP loves to snap driveshafts!
There are a few considerations to take into account before completing a design or solution.

1. The output flanges on the medium case 188 diffs are a known weak point. They should be changed to either large case E28/E34 or Z3m types but ideally they should also be made from chromoly 4340 or 300M. This will ensure that they have some spring/flex in them.

2. The half shafts should either be changed to chromoly 4340 or 300M rods whilst rifled tube is stronger and lighter but will probably cost a lot more to manufacture. This will ensure that they have some spring/flex in them too that also matches the output flanges spring/flex.

3. The CVs are again prone to shattering too the GKN 108 mm CV joints are a really strong cheap serviceable alternative. However you can use these on the inner sides (diff flanges) without any problems what so ever there are clearance issues on the outer sides (hub side).
This is why people manufacture axle hub stub extensions to bring the outer CV away from the rear hub face. Again these are made from either 4340 or 300M this ensures the load is also spread evenly being that no part is stiffer than the other.

4. The hubs are again a consideration that needs to give some serious thought because they will also be from a inferior metal and can literally detach all the splined surface area from the hub given enough torque and tyre grip.

Maybe we should consider having CVs made with a thicker design rather than a larger diameter on the outer this will ensure adequate clearance around the CV as most serious cars needing uprated shafts will be running rear coil overs.

I am currently looking at lots of possibilities to try and find a comprehensive solution that will never fail below 1000nm but it is all pretty long winded and costly if you have any suggestions please let us know! I am sick of buying reconditioned crap from GSF or ECP but as GKN don't manufacture new e30 CVs anymore there are not many options. Even the ones from the dealers are remanufactured rubbish too........

PM me if you would like to discuss it further.

Sam

[TomCresswell]

PM sent Sam