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Discussion Starter #41
Thanks graeme! i think? lol

Steve the best i can do weight wise is weigh my car when its finished, then work out the engine/trans weight by working out what an engineless shell weighs.

What i can say though is that the engine itself is not that heavy, no more than the V6 is for sure, id say the trans is about 5kgs heavier than a E153 trans at a guess.

Pushing my car around it feels no heavier than when it had the v6 in it.... time will tell i guess!
 

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Discussion Starter #42
Quick update, here is my drivers side driveshaft, remember here we are trying to mate an Audi gearbox to Toyota hubs.... so without going for full custom made driveshafts which is a VERY expensive thing to do i needed to find a solution.

This is an Audi driveshaft from the 2.0ltr TDI model and i have managed to find a Toyota CV joint that slotted straight onto the Audi shaft :shock: I mean stuff like that just doesn't happen normally!

This shaft is now completely Plug and play on the drivers side, no other mods needed, it just works.



On the passenger side i need to use the same Toyota CV joint but i do need to shorten the driveshaft, details on that will happen when we actually do it but it is pretty simple due to the design of these shafts.
 

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Discussion Starter #44
They most certainly do, same spline count/diameter and bearing seal face diameter.... and also slide straight onto the Audi shaft, the snap ring on the audi shaft even clicks into the joint properly.... you can't make this stuff up! It took many hours of research to find this out and a fair amount of blind luck.
 

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Discussion Starter #45
Ok i think the swap gods have truly blessed this conversion! Things just seem to be getting easier and incredibly luckier as i go.

The plan for the left side driveshaft was to cut down the Audi shaft, have a machine shop lathe me up a perfect fitting bar to slot into each side of the cut shaft and then weld the whole thing up.A perfect fitting inner bar is the only real way i could see to guarantee a straight shaft.I know it will still need to be balanced afterwards anyway but getting it initially straight was the first plan of attack and i thought only having a specially lathed insert would be the only way.... until this happened....

I cut the Audi shaft and removed about 2" from it to make it the correct length for the car, then i took an internal bore measurement of the shaft using the micrometer and it was 26.15mm exactly.

Out of curiosity i started randomly measuring bits of steel rod/shaft or whatever i could find with approximately the same measurement, i thought well if i find something say 27 or 28mm i will get that turned down to the right diameter.Then i stuck the micrometer on the shaft of an old scrap Mk2NA right side axle and i could not believe it when the mic read 26.2mm!!! So i immediately cut a section of the Mk2 shaft out...



I cleaned it up and test fitted it into the audi axle....a nice tight fit! Absolutely perfect! I mean you just do not get luckier than this.

Here it is alongside the Audi shaft before being inserted....



And here it is inserted into the shaft, you can see i have cut slots in each side of the shaft to weld through to the bar as well as welding it around the join.



Will it be strong enough? I honestly don't know as nobody has ever done it this way before to the best of my knowledge, I am taking every measure to make sure it will be strong though, and this is the only alternative i have at the moment instead of a custom made shaft costing $$$$$...if it breaks then i will find a way to make it stronger but i think it will be ok.

So all that is left to do is make sure this shaft is balanced ok, but the Mk2 shaft insert has worked perfectly....i can't believe a mk2NA shaft is the perfect diameter to fit inside an Audi shaft.... thankyou swap gods!
 

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I cant wait to see this finished Paul.

What power does the engine put out, should be interesting to see how it handles with the V8 in there!

Good luckl - not that you seem to need any luck at the moment you have plenty haha

Graeme
 

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Discussion Starter #47
My AHC version puts out 340bhp in standard form on the stock ECU with cats.... but i am going standalone and i don't need cats at all so who knows? 350/360 maybe?
 

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I would have a sleeve machined that can be welded to the outside as well, like the guy in Europe did on his transverse 1uZ-FE in a Mk1
 

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Discussion Starter #49
That is something i did consider and could be added later, i am actually more concerned about a thin area on these shafts just before the outer CV.... if you look at the right side of the 2nd ast pic i posted you can see the area i mean.The shaft goes from thick to thin then goes thick again before the spline, i think if i'm going to see a problem it will be there or at the hub spline.
 

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I had my new drives hafts made out of solid material for this very reason.

It wasn't cheap, but the thought of a snapped drive shaft flailing around while travelling at 70 mph ripping out bodywork and suspension components didn't really appeal.....

Hilly
 

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paul woods said:
That is something i did consider and could be added later, i am actually more concerned about a thin area on these shafts just before the outer CV.... if you look at the right side of the 2nd ast pic i posted you can see the area i mean.The shaft goes from thick to thin then goes thick again before the spline, i think if i'm going to see a problem it will be there or at the hub spline.
Maybe.

I know you are thinking of torsion failure due to a reduction in cross sectional area.

However, axles usually fail at the root of the spline, due to fatigue (crack formation) if there is no spline relief. There should be a relief machined at the root of the spline eliminating sharp corners where the spline ends along the length of the shaft.

Back when I was engineering/designing for a living, we did a similar relief at the end of the threads of the piston rod of hydraulic cylinders. It was for the same reason, there is where cracks start and lead to fatique failures. Piston rods are in tension/compression only, but fatigue failures are still a problem. We usually machined the relief slightly smaller than the thread minor diameter (the valleys of the threads), and we spec'ed out a certain finish in those reliefs. Any tool marks were a source of crack formation. With these precautions, piston rods usually did not fail at the threads or thread reliefs.

On the GM Pontiac G6 axles that I have, they are a little bit thinner than the MR2 turbo axles, but have proper spline reliefs. The MR2 turbo axles do not (shame on Toyota!). I see your Audi axles do not have reliefs either. I guess for street cars, failures there are uncommon. Race cars always have reliefs (or else!).
 

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Discussion Starter #52
That's useful information, i had no idea the spline relief even existed on some axles, you learn something new everyday!

I'm happy to take a chance with these shafts on my own project, my testing will be a slow build up of power runs/confidence in the car right up to full hard launches in the dry with the traction control on full.If they survive that over a period of weeks then great, but i will never do more than 20-30mph during this testing phase just in case.
 

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The GM axle has a proper relief because the relief diameter is just a hair under the minor diameter of the spline.

The MR2 axle in the center has a relief, but its so poorly done, it would not matter if it was there or not. The relief diameter is just a hair OVER the minor diameter of the spline. There is a small sharp notch at the end of the splines. This is where cracks start, leading to fatigue failures.

The intermediate shaft is much larger in diameter at the splined end than the CV half-shaft so Toyota felt it unnecessary to put a relief there, probably because they felt the CV shaft would break first. Thanks to thier crappy half shaft relief, they are correct.
 

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Discussion Starter #56
My V8 engine harness has now been sent away for modifying and ECU building.When it comes back getting the engine running will not take long at all.
 

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If you are still planning on welding those shafts together , ill suggest beveling thoses edges a little deeper and have a VERY qualified welder take his time doing it .. And use some kind of sleeve over it to reinforce it better .. thats a hell of a risk to not spend the time on it .. but either way AWSOME build
 

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Discussion Starter #58
Advice noted, i welded them myself, i have been welding for nearly 20 years though so i think i have enough faith in my own ability.If the shaft fails then i will find a stronger way to do it.
 

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Discussion Starter #60
The engine harness is now with hilly for modification and Vems ecu... so i cant do a lot until that comes back.
 
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