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Yeah, it's the pre-load issue that puts me off removing the input flange. I was thinking that some careful swipes with a fine file avoiding the un-corroded areas would be the best approach.
As far aware, the prop was balanced with both flanges fitted. When I opened the holes out 10mm to 11mm, I did it with everything still attached, I've never actually separated the slip joint as there's never been the need.
It's in the post so I just have to wait and see now.
Best avoid files as they cause raised areas at the edges of the cuts. An engineers scraper (made cheaply as above) is the preferred method and you will be surprised how well you can locally remove metal (or rust flakes) without disturbing the surrounding metal. Secure the flange in a vice and use both hands, one to do the pushing bit but the other to control where you are workig. Peter.
Good advice Pete. I actually found a broad gasket scraper amongst my tools and that did the job nicely.
I used a screw driver to scrape the corrosion out of the recess and then blocked the face of the flange with some wet and dry. I also ran a small wire brush wheel around the inside of the recess with a dremel to ensure there was no crud left in there to spoil the fit.
It's now lovely and smooth with very little corrosion left (as you can tell by the brightness of the flash reflection). I've smeared a little copper grease over it now just to keep it that way.
Best not to get me started. Having posted the prop back to Autoprop UK on Saturday morning, Parcel Force have been incapable of finding the address until 5pm today despite 4 calls in the evening over the week to explain how to get to a location that is clearly visible, with a sign from the main road. I can see it nearly 200 miles away using google street view so they must be pretty incompetent as I could find my way there with nothing more than an AA road atlas if not memorising the route.
I'm pretty sure the £17 it cost me was for a ParcelForce48 service, not ParcelForce152.
I'll let you know once Autoprop have come back to me. It should be a pretty simple job to take the yoke off, machine the back and re-assemble.
cheers
Ian
How completely frustrating for you. Why is it that the more automated and computerised things become, the people that use them seem to lose all sense of direction, location initiative and common sense! Ah well soap box put away now! Hope the wait for the prop is worth it in the end. Peter.
I spoke to Mike down at Autoprop on Tuesday to make sure he understood the problem but he hasn't got back to me yet. I'm going to chase tomorrow as the days are getting colder, nights drawing in and I want to get some shake down time on the car before the winter. Hopefully he'll have good news for me.
They've not done quite what I asked for which was to cut a recess a certain size concentric to the the locating part but this dish shape should still work just as well. It's the same principle used on the BMW part (pic courtesy of peterux)
I noticed that the balance weights originally welded on are now missing but there's fresh paint, so maybe it was incorrectly balanced from the start too? Or maybe it's now going to locate properly but be out of balance
No time to fit it tonight but should know if my problem's solved by Saturday
I noticed that the balance weights originally welded on are now missing but there's fresh paint, so maybe it was incorrectly balanced from the start too? Or maybe it's now going to locate properly but be out of balance
Let's hope this one is good!
Looks to me like that is a completely different flange so hopefully they have rebalanced the whole shaft. The 'scooped out' cavity looks good but the raised locating spigot looks a bit shallow?
And I can't understand what could have caused those tangential scratches? As a custom propshaft builder I'm a bit surprised they don't have a standard BMW diff flange.
yes, there is very little meat on that spigot, it's bang on 2mm deep but unfortunately there's not much room for more on the diff input side. I'll install tomorrow and see how things look. If there are still problems, I may have to just cut my losses and try a different manufacturer.
It's the same flange, I stripped the paint off before I sent it away. I did wonder about the scratches myself. The camera flash makes them look worse than they do in the flesh
I'm happy to report the modification to the prop has made a massive improvement. There is still a little vibration there as you pass 55-60. I noticed this while testing still up on stands with the rear wheels off so was worried that it was still going to cause a problem. Having driven the car around 30 miles today, by the time you hit 60 there are plenty of other more intrusive things going on like wind noise, watering eyes and oxygen depletion. I'm going to play around with the jubilee clip trick to see if I can find an imbalance. If I can work out where it is I can weld some metal on.
For a general running report:
- The car pulls very well once you get over 4000rpm but feels a little 'normal' up to that point. I think this may be a point of view thing and the inaccuracy of my backside dyno rather than anything to do with actual performance, I just expected to be a little scared, and wasn't. I think the swap to a 3 litre M50 stroker or something generally more hefty in the engine dept needs to move up the todo list
- my side light fuse has decided to reliably blow every time I turn them on so I need to track that down.
- my oil pressure lamp keeps flicking on at low rpm. I'll change the oil as I have some of that valve lifter cleaning additive in at the moment which may have caused the viscosity to drop too much. The oil pressure gauge generally seems to read low anyway so maybe I do actually have pump or sender issues.
- I had a weird 5 minutes where the electrics died on me. Turned the key and the LP pump started up. Hit the start button, the starter clicked once and then a few seconds later the pump stopped. No electrics at all worked for a minute or two while jump leads and jump starts were considered at which point, I tried again and it fired straight up.
- having the shocks set on 1/2 way stiffness is way to much for my spine. I'm going to set them back to nice and soft and jack up the rear a little. I'm sure for the track having this adjustment is great, but for the road, I'd advise just saving the money and buying standard dampers. I suppose the spring rate on the rear springs supplied by marlin (400lb) could be part of the problem too.
- I need to buy some goggles, sun glasses just don't cut enough of the wind out and at speed you're blinking back the tears. An intercom may also be on the cards. Oxygen masks would also be nice though maybe a scarf over the mouth would help there.
- no need for a heater. I found that although my face was cool my body was more than warm enough even on a cold, damp day like today (though female passengers do seem to disagree with this point). I am used to wandering around on the top of Welsh mountains with 40-70mph winds blowing and rain lashing my face in the name of fun, so this may also be a point of view thing.
- The aux drive belt squeals quite a bit at higher revs - I think this is minor misalignment between the alternator and the other main pulleys plus my totally unscientific tension adjustment method. I'm planning on getting a new smaller alt anyway so can look into this at the same time. I'm hoping to move it back to the nearside where it should be on the original fixing points.
- I need to look a bit harder at tyre pressures and toe angle. Since dropping the pressure to 23 psi and swapping to a few mm toe in, you have to very deliberately straighten up after pulling out at junctions etc and concentrate on keeping it in a straight line normally.
- though nice to look at, my dash layout is rubbish. Nothing is easy to glance at including the speedo meaning that at the moment, especially with concentration required to drive straight, all the instruments are essentially redundant. I'll leave as is for now but there will be a future plan to move things around a bit.
- my front wing stay minor mod seems to have made them rattle much less but I'm still getting way too many general rattles from the car. I don't currently have any spring rubbers on the rear which would help I think. A lot of it is probably just normal noises you are sheltered from in a production car but I'm driving with a nagging doubt in my mind that I've not tightened everything up properly.
- baseball caps and aero screens don't mix as I found out as soon as I hit 60 and had to turn the car around to go back and retrieve mine from the middle of the road. Driving without a hat isn't actually uncomfortable, you just have to remember to de-bouffant your hair at the end of the journey
- The car pulls very well once you get over 4000rpm but feels a little 'normal' up to that point. I think this may be a point of view thing and the inaccuracy of my backside dyno rather than anything to do with actual performance, I just expected to be a little scared, and wasn't. I think the swap to a 3 litre M50 stroker or something generally more hefty in the engine dept needs to move up the todo list
- having the shocks set on 1/2 way stiffness is way to much for my spine. I'm going to set them back to nice and soft and jack up the rear a little. I'm sure for the track having this adjustment is great, but for the road, I'd advise just saving the money and buying standard dampers. I suppose the spring rate on the rear springs supplied by marlin (400lb) could be part of the problem too.
- I need to look a bit harder at tyre pressures and toe angle. Since dropping the pressure to 23 psi and swapping to a few mm toe in, you have to very deliberately straighten up after pulling out at junctions etc and concentrate on keeping it in a straight line normally.
Hi Ian
Your first impressions are very much like my own:
Performance below 4000rpm seems bland - I expected more, but over 4000 rpm and it feels lively, but very quickly hits the limiter: this is why I started to persue the M54B30, as it has significantly more low down torque due to the longer throw crank, bigger capacity, and the DISA which changes the runner lengths to improve low down torque.
Maybe you are sub-consciously comparing it to your 3.0 Tourer, or your M3?
My shocks are GAZ adjustables - the common concensus is run them on only 3 or 4 clicks above the softest setting.
Self centreing seems to be more of a black art than a science - I kept increasing castor, and found the self centreing worked better going backwards! Once I have had it painted and rebuilt it, I will have a professional wheel alignment set up to see how much self centreing I get.
I was expecting the acceleration to feel very similar to the M3 as the power to weight is very similar. I think because there is so much extra head room with the revs on the M3 you drive higher under normal conditions without realising. With the M50 you're more conscious of approaching the red line so instinct (and exhaust noise) makes you change up too soon.
I also wonder if my diff is having an impact here as it was from an automatic donor. RealOEM says it is a 3.15 but other sources (bokchoys.com) say 3.91,which should be much better for acceleration. I actually thought it was a 2.93. The M3 has a 3.62 so if mine is a 3.15 that could account for some of the difference. So many other factors though.
I think you're right about the extra crank throw on an m54, it will give greater low end torque which is the real thing you experience during acceleration.
I was expecting the acceleration to feel very similar to the M3 as the power to weight is very similar. I think because there is so much extra head room with the revs on the M3 you drive higher under normal conditions without realising. With the M50 you're more conscious of approaching the red line so instinct (and exhaust noise) makes you change up too soon.
I also wonder if my diff is having an impact here as it was from an automatic donor. RealOEM says it is a 3.15 but other sources (bokchoys.com) say 3.91,which should be much better for acceleration. I actually thought it was a 2.93. The M3 has a 3.62 so if mine is a 3.15 that could account for some of the difference. So many other factors though.
I think you're right about the extra crank throw on an m54, it will give greater low end torque which is the real thing you experience during acceleration.
I swapped a 3.14 Sierra diff into my Cabrio, but found the M50 could not make good use of fifth gear - 85mph in a Cabrio is just too fast to be reaching the start of the power band! So I swapped back to my 3.38 diff. This seems better geared through the revs, and puts the m50 into a better rev band at 70-75mph.
A 3.62 diff would be a good choice to go with the M50, although it might become tiresome on a long journey. The ideal might be pairing with a ZF 6 speed with an over driven top gear (0.85:1) driving a 3.62. This would have sharper acceleration through the lower gears, but cruise nicely in 6th.
I am hoping (confident?) my M54B30 will be happier to operate at lower revs, and with higher torque will perform nicely with the 3.36 diff, making cruising much more enjoyable.
- The car pulls very well once you get over 4000rpm but feels a little 'normal' up to that point. I think this may be a point of view thing and the inaccuracy of my backside dyno rather than anything to do with actual performance, I just expected to be a little scared, and wasn't. I think the swap to a 3 litre M50 stroker or something generally more hefty in the engine dept needs to move up the todo list
Hi Ian,
whilst pondering the design of my 'standard' BMW 328i exhaust system got me wondering why it is so complex. Why is one header to cat pipe 45mm diameter and the other 50mm? Why is there a crossover after the cats on a straight six engine? Clearly BMW have put a lot of design effort into this exhaust system. I guess performance, emission and sound are all factors they have to consider.
I'm wondering if your custom built 6 into 1 header and single bore Jetex cat is affecting your torque below 4000rpm?
Just food for thought and research on a cold winters night
The bit of the exhaust downpipes I retained for my M54B30 engine on it's stand is similar. The pipes are seemingly random dimensions and appear to be a mix of stainless and mild steel welded together. I noticed this when trying to decide where to chop them and weld in some off the shelf bends to make a short system for running on the stand.
I have wondered about my custom manifold. The length and internal dimensions of the pipes from each cylinder are the same as the original cast piece but the merge on the 2-1 part of the down pipes happens sooner than it did on the original and goes to a larger bore. The original M50 exhaust (below), being for an engine management system with a single O2 sensor, merged to a common pipe anyway, unlike later designs, so I don't think it would have a massive effect
I think the science behind exhaust design, header lengths etc is more about getting noticeable gains rather than causing noticeable loss. My E46 325 is two completely separate pipes all the way to the back and it similarly doesn't perform well until you get the revs up.
I think it's really just down to perception more than anything. The BMW straight 6s are known for liking revs rather than delivering low end torque. I'd just assumed that with the weight gone, that constraint would be magically removed. In most peoples minds it would still feel really fast, I just have high expectations. Like Mike says, I've probably just got used to the M3 but with the lack of rev range on the Marlin, it feels like you're having to rag it to get the performance out of it.
Acceleration vs noise will also have an impact as I'll be associating lower rev loud noise with what would normally occur much higher up in the rev range on a normal car so my ears are telling me it's time to change gear when I'm barely past 3000rpm. The (as it turns out) useless layout of my dash means I don't easily notice the actual engine speed either.
As I've only done about 30 miles so far, it's too early to call, I need to get used to it. The weather the last few weeks means it's been sat in the garage. Last weekend was dry enough but it was 2 degrees out of the wind so I had no intention of going out in that.
....hhmmmmm, I wish I understood the reasons for the different BMW designs.
So your 325 has two pipes with no crossover, my 328 has a crossover after the two cats and your M54B30 has a 2 into 1 before the two cats and then two separate paths after? (or is that a fancy crossover before the cats?).
It looks from that picture this system also has a smaller diameter pipe for the rear bank of three cylinders?
I guess as your planning to upgrade to the M54B30 anyway so this is probably an irrelevant discussion
No sorry, the photo is the original system for the E36 M50 325
The E46 M54B25 325 has separate pipes all the way back but with the pre-cats and 4 O2 sensors (pre and post for each bank) in the manifolds. It also then has post cats further down but no cross pipe, just a mid section resonator and the back box. This one is stainless all the way RealOEM E46 325 Front Section (top pic) RealOEM E46 325 Mid and Rear Section
I don't have the little vacuum valve that dampens the noise at idle
The E46 M54B30 also had straight pipes but without cats in the manifold so just 2 O2 sensors before cats under the car. These then go through the cats under the car and merge into one pipe that goes to the back. This one is a mix of weird size mild steel pipe at the front, stainless in the middle, then mild on the single pipe back. I assumed when I first saw it someone been doing some dodgy cheap repairs it was that untidy, until I looked on RealOEM. RealOEM E46 early 330 front section RealOEM E46 early 330 rear section
When they stopped using the weird air pump you see on some early E46s this changed to a system the same as my E46 325
The M3 has stainless all the way, proper 6-2-1 branch manifold with the pair of cats under the car with a balance pipe after the cats. It's separate pipes all the way to the back. Who knows what happens in the massive back box though before the four tail pipes emerge RealOEM E46 M3 front section (bottom pic) RealOEM E46 M3 backsection
The M3 retains the air pump from the earlier cars as not having pre-cats it needs to lean out the exhaust to get the cats under the car up to temp quickly on first start up.
It's this mix and match that leads me to believe they spent much more attention on noise levels, cost and emissions regulations than performance so my straight through 6-2-1 (but shorter) with a 200 cell sport cat and twin back boxes 'should' only affect top end performance in a positive way though it may well have moved the torque curve a little.
I wonder if the air pump would now be considered a 'defeat device'? It's certainly a waste of engine bay space.
No sorry, the photo is the original system for the E36 M50 325
It's this mix and match that leads me to believe they spent much more attention on noise levels, cost and emissions regulations than performance so my straight through 6-2-1 (but shorter) with a 200 cell sport cat and twin back boxes 'should' only affect top end performance in a positive way though it may well have moved the torque curve a little.
Sorry for not reading your original post correctly. BMW certainly liked to mix and match their designs.
I hope you get some nicer weather soon so you can get some more road testing.....
