BMW 330CI E46 Build thread
Discussion
As we start to move into spring I've started to look at Trackdays for 2024, I was hoping to get more miles on the car this year, but we'll see how that progresses through the year, noticed a lot of people selling up track cars this year, possibly down to the constant rising of prices and the costs of cars?
Following on from Oulton I'd made the decision that I wanted to go back to giving ABS a try on the E46. In OEM form I never got on with the ABS and brake system as a whole, the main reason for that is the standard braking system run a 52% / 48% brake bias which resulted in constant intervention from the ABS for the rears. I ditched the system and went with ABS delete and have rated that set up with a Wilwood proportioning valve.
Looking at the data from Track days in 2023 on average the bias is between 60% / 40% - 56% / 44%
Going with ABS one option is to go to a M3 Master cylinder which would bring it down to 53% - 47% but it still isn't in the range I would have become accustomed to and isn't adjustable,
Old Bias location - Prior to removing interior and brake lines.
I started using what braided lines I already had on the car for the front lines and refitted the front hard line from the master cylinder to the ABS Pump
Ordered lines for what I didn't have, I reached out to Matt at Brake.Shop.co.uk and ordered some link lines and full lines to go to the rear of the car to join the current braided lines.
Plumbed up the remainder of the ports with braided lines
What I have decided to do is take the Rear master cylinder output and ran it to the proportioning valve and ran this back to the ABS Pump.
This gives me the chance to run the same rear bias as before and still utilise the ABS pump.
The pump im using is the MK60, this is a really commonly fitted pump to a lot of cars and has a bit online following, There are a range of ABS pump controllers available, some which can be reflashed with different software but that is something to look at down the line, The main advantage is this one is set up for the E46 and just works.
Took a bit of a fiddle but managed to get connected to the MK60 ABS using Ista and INPA. Was good to check the live data as well as going through the function of the ABS switch and fire all the pump to bleed the system correctly, this process took me about 3 days using various different techniques, it wasn't made any easier with the additionally lines and loops I've added to the system.
Whilst the seats are out I've removed the driver footplate, I end up replacing the grip tape on this ever two of three trackdays as I tend to dig my left heal into the floor when driving and it pulls the tape off all the time.
At one point over winter I was considering looking for a front carpet, yes I did cut one to bits in 2018 and throw it in the skip, oops, how things change, but the work needed to get one and then refit it I decided i would just carpet the foot plate.
This is one change I am really happy with, it's tidier and just feels nicer.
Last few changes have been to the logger and the screen.
Added a lot more Canbus channels to the logger from the ECU as well as adding some more data to the screens relating to the brakes. Bias viewable on the fly.
I have also been working on a screen which monitors and logs wheel lockups and slip rates when braking in straight line, hope it will be interesting to use as data for dialing in braking and actually seeing what the wheels are doing.
At some point I will update the graphics on this display to something which is a little easier on the eye and 'fancy' but for the time being function!
I am keeping my eye out for a replacement drivers seat too. Looking for a Sparco Circuit to match my current seats but waiting for the right seat at the right price at the moment.
I'm sure there will be more before Cadwell in April. I am looking at some form of graphics and colour being added to the car before then but that is a bit of random idea at the the moment... Watch this space.
Following on from Oulton I'd made the decision that I wanted to go back to giving ABS a try on the E46. In OEM form I never got on with the ABS and brake system as a whole, the main reason for that is the standard braking system run a 52% / 48% brake bias which resulted in constant intervention from the ABS for the rears. I ditched the system and went with ABS delete and have rated that set up with a Wilwood proportioning valve.
Looking at the data from Track days in 2023 on average the bias is between 60% / 40% - 56% / 44%
Going with ABS one option is to go to a M3 Master cylinder which would bring it down to 53% - 47% but it still isn't in the range I would have become accustomed to and isn't adjustable,
Old Bias location - Prior to removing interior and brake lines.
I started using what braided lines I already had on the car for the front lines and refitted the front hard line from the master cylinder to the ABS Pump
Ordered lines for what I didn't have, I reached out to Matt at Brake.Shop.co.uk and ordered some link lines and full lines to go to the rear of the car to join the current braided lines.
Plumbed up the remainder of the ports with braided lines
What I have decided to do is take the Rear master cylinder output and ran it to the proportioning valve and ran this back to the ABS Pump.
This gives me the chance to run the same rear bias as before and still utilise the ABS pump.
The pump im using is the MK60, this is a really commonly fitted pump to a lot of cars and has a bit online following, There are a range of ABS pump controllers available, some which can be reflashed with different software but that is something to look at down the line, The main advantage is this one is set up for the E46 and just works.
Took a bit of a fiddle but managed to get connected to the MK60 ABS using Ista and INPA. Was good to check the live data as well as going through the function of the ABS switch and fire all the pump to bleed the system correctly, this process took me about 3 days using various different techniques, it wasn't made any easier with the additionally lines and loops I've added to the system.
Whilst the seats are out I've removed the driver footplate, I end up replacing the grip tape on this ever two of three trackdays as I tend to dig my left heal into the floor when driving and it pulls the tape off all the time.
At one point over winter I was considering looking for a front carpet, yes I did cut one to bits in 2018 and throw it in the skip, oops, how things change, but the work needed to get one and then refit it I decided i would just carpet the foot plate.
This is one change I am really happy with, it's tidier and just feels nicer.
Last few changes have been to the logger and the screen.
Added a lot more Canbus channels to the logger from the ECU as well as adding some more data to the screens relating to the brakes. Bias viewable on the fly.
I have also been working on a screen which monitors and logs wheel lockups and slip rates when braking in straight line, hope it will be interesting to use as data for dialing in braking and actually seeing what the wheels are doing.
At some point I will update the graphics on this display to something which is a little easier on the eye and 'fancy' but for the time being function!
I am keeping my eye out for a replacement drivers seat too. Looking for a Sparco Circuit to match my current seats but waiting for the right seat at the right price at the moment.
I'm sure there will be more before Cadwell in April. I am looking at some form of graphics and colour being added to the car before then but that is a bit of random idea at the the moment... Watch this space.
d_a_n1979 said:
Some serious work in this car Tom; bet it's a superb drive
Is it road legal still or now just a track car?
Thanks. A lot of hours have got into building this and as you can imagine it is fantastic to drive now. However, I am unsure what would be changed next, if anything?Is it road legal still or now just a track car?
Will see how it goes next time it's out in April.
That's a good question. It is missing a lot now to be road legal, but It wouldn't take much to put it back on road, I did consider it over the winter, however I decided against it, in the future if I want to go back down the route I will sell the car and buy something that I can use on the road at the weekend and still do the odd track day in. I'll admit it is something I have considered lately.
I took the car off the road in around 2019/2020, it wasn't getting driven on the road besides the odd test drive and paying out for insurance, MOT and tax each year just wasn't worth it, it was quite easy to make that decision though when I already owned a trailer had the VW T6 for Towing.
Only 5 weeks till I'll be out at Cadwell - Photo from 2023
Found a replacement for the smaller more club sport seats I've had in the BMW since the Clio prior to 2018, these have been great and are still in perfect condition and were brilliant when driving the cars on the road, but always wanted to try something a little bit different, little more support and slightly different feel.
Been keeping an eye out for this specific seat as it is the same material and design as my Pro2000 seats.
Possibly keep my eye out for a second one for the passenger side.
I thought I was pretty much ready to go for Cadwell Park on Monday, but decided to make some changes to the suspension set up ahead of Cadwell, back on axle stands it goes.
Going back to the softer rear springs 350lbs and refitting the rear anti roll bar, this is the set up I've ran for the past couple of years and it's the best feeling setting up I've had but I don't think it's quite optimum.
I'd experimented with a firmer rear spring which caused even more wheel lifting and inside wheel slip under power. I then kept the stiffer rear springs and dropped the ARB when worked well at Oulton in the wet allowing the inside wheel to remain in contact with the floor helped drive out of corners. But overall I think a stiffer front anti roll bar is a better direction to go, more on this when it turns up.
Springs and dampers swapped back to the original set up.
Wheels washed and cleaned while off the car,
There's always something else going on in the background too, modifications to output flanges for a Porsche gearbox...
Been keeping an eye out for this specific seat as it is the same material and design as my Pro2000 seats.
Possibly keep my eye out for a second one for the passenger side.
I thought I was pretty much ready to go for Cadwell Park on Monday, but decided to make some changes to the suspension set up ahead of Cadwell, back on axle stands it goes.
Going back to the softer rear springs 350lbs and refitting the rear anti roll bar, this is the set up I've ran for the past couple of years and it's the best feeling setting up I've had but I don't think it's quite optimum.
I'd experimented with a firmer rear spring which caused even more wheel lifting and inside wheel slip under power. I then kept the stiffer rear springs and dropped the ARB when worked well at Oulton in the wet allowing the inside wheel to remain in contact with the floor helped drive out of corners. But overall I think a stiffer front anti roll bar is a better direction to go, more on this when it turns up.
Springs and dampers swapped back to the original set up.
Wheels washed and cleaned while off the car,
There's always something else going on in the background too, modifications to output flanges for a Porsche gearbox...
Little bit of free time over easter has given me the opportunity to make some changes to a few bits. Had a little bit of time yesterday on CAD to look at the design of the rear wing, it's a little bit bigger than I ever thought I'd have on the car, the end plates I originally designed and cut were more of a mock up and they ended up staying,
Version 2 - Cut outs in the up rights and smaller end plates with a less square design
I have already laser cut some end plates from this to mock up and will get the uprights cut out of 10mm aluminium soon.
Mock test of the uprights
Ordered a new front ARB, this one being 30mm compared with the OEM which is around 23/24mm. This carries on from the previous post where I've refitted the rear ARB and gone back to the softer springs which was always my preferred set up, I'm hoping this should remove some of the front roll out of the car and help keep the car from pitching and lifting the inside rear when loading the opposite side front. We'll see what effect it has in practise.
Fitted with polybush to suit and the ARB came with some 'lovely' rose jointed adjustable drop links...
However they are no good really, the drop links aren't supplied with spacers to space the drop link away from the ARB and the shock tab and there isn't enough room for the rose joint/shock to articulate through it's full steering angle without it binding up at some point. I did mock it up with some washers but it's just a poor solution, Maybe at some point I'll make some much longer aluminium spacers to get the spacing better and look at the artiulation a little more, but given the standard drop links a quick clean and they've gone back on.
Did a quick google and this appears to be a common thing amongst this style drop links, most people going with a standard ball joint style.
Quite a considerable difference, one thing to consider is it's not just the diameter of the roll bar, also the material it's made from, but this should be quite noticeable, thicker than what is normally fitted to an E46 M3, more in line with what was fitted to the E46 CSL
Last job for today, fitted a new battery, the Odyssey has been on the car since 2018, I've always done my best to keep it charged, however I think it's slowly start to die over the past 6 months but I generally keep it on the trickle charger. with the car not being ran or moved over winter I hadn't noticed anything but when I was sorting out the ABS I let the battery completely die by clearing the OBD lead plugged in for a few days and when I came to it the battery was completely flat. Tried to recondition it with a couple of different chargers but it just isn't holding charge for more than 2 days dropping down to 11v and below. A replacement is now £140 so looked at some alternatives that are the same dimensions and comparable spec,
Ended up with the Lucas LSLC22-12G 22Ah vs 16Ah.
We'll see how it goes but for £45 replacement,
Version 2 - Cut outs in the up rights and smaller end plates with a less square design
I have already laser cut some end plates from this to mock up and will get the uprights cut out of 10mm aluminium soon.
Mock test of the uprights
Ordered a new front ARB, this one being 30mm compared with the OEM which is around 23/24mm. This carries on from the previous post where I've refitted the rear ARB and gone back to the softer springs which was always my preferred set up, I'm hoping this should remove some of the front roll out of the car and help keep the car from pitching and lifting the inside rear when loading the opposite side front. We'll see what effect it has in practise.
Fitted with polybush to suit and the ARB came with some 'lovely' rose jointed adjustable drop links...
However they are no good really, the drop links aren't supplied with spacers to space the drop link away from the ARB and the shock tab and there isn't enough room for the rose joint/shock to articulate through it's full steering angle without it binding up at some point. I did mock it up with some washers but it's just a poor solution, Maybe at some point I'll make some much longer aluminium spacers to get the spacing better and look at the artiulation a little more, but given the standard drop links a quick clean and they've gone back on.
Did a quick google and this appears to be a common thing amongst this style drop links, most people going with a standard ball joint style.
Quite a considerable difference, one thing to consider is it's not just the diameter of the roll bar, also the material it's made from, but this should be quite noticeable, thicker than what is normally fitted to an E46 M3, more in line with what was fitted to the E46 CSL
Last job for today, fitted a new battery, the Odyssey has been on the car since 2018, I've always done my best to keep it charged, however I think it's slowly start to die over the past 6 months but I generally keep it on the trickle charger. with the car not being ran or moved over winter I hadn't noticed anything but when I was sorting out the ABS I let the battery completely die by clearing the OBD lead plugged in for a few days and when I came to it the battery was completely flat. Tried to recondition it with a couple of different chargers but it just isn't holding charge for more than 2 days dropping down to 11v and below. A replacement is now £140 so looked at some alternatives that are the same dimensions and comparable spec,
Ended up with the Lucas LSLC22-12G 22Ah vs 16Ah.
We'll see how it goes but for £45 replacement,
I used to run an M3 Conv. front arb-27mm on all my E46s. Despite theory that it would increase understeer-it didnt. It reduced roll without a reduction in ride quality. This was on road cars, not track. I’m sure your 30mm bar will work well. If only BMW had made the E9x suspension as good as the E46!
Hi Tom,
I also upgraded my front arb to a 30mm version from the standard 24mm e330 version. On AR1/Trofeo track day tyres, it reduced understeer, front end was more predictable. I too had the same problem with drop links and reverted to standard drop links.
I have a 330ci shell with m3 running gear including the m3 master cylinder. I do not get any locking of front or rear wheels under braking. No changes to the abs software. I do however have 6 pot calipers which increase front braking.
I am also progressing my data logging journey, using the Innovate gauges and their data logger. In short term, my interest is oil pressure, water temp and oil temp. It never stops does it!
Good luck with your upgrades. I will continue following your thread as our cars have many similarities. Maybe we will meet up at Oulton or Cadwell later in the year.
Cheers
Richardracer
I also upgraded my front arb to a 30mm version from the standard 24mm e330 version. On AR1/Trofeo track day tyres, it reduced understeer, front end was more predictable. I too had the same problem with drop links and reverted to standard drop links.
I have a 330ci shell with m3 running gear including the m3 master cylinder. I do not get any locking of front or rear wheels under braking. No changes to the abs software. I do however have 6 pot calipers which increase front braking.
I am also progressing my data logging journey, using the Innovate gauges and their data logger. In short term, my interest is oil pressure, water temp and oil temp. It never stops does it!
Good luck with your upgrades. I will continue following your thread as our cars have many similarities. Maybe we will meet up at Oulton or Cadwell later in the year.
Cheers
Richardracer
Hi Tom,
I forgot to ask, what sort of lap time improvement did you get with using slicks vs. AR/1 or similar track day tyres? Something we are thinking about, along with a fuel swirl,pot after getting surge, even with the 2 pump solution. Could you sow the mounting for your front mounted swirl pot please?
Thanks
Richardracer
I forgot to ask, what sort of lap time improvement did you get with using slicks vs. AR/1 or similar track day tyres? Something we are thinking about, along with a fuel swirl,pot after getting surge, even with the 2 pump solution. Could you sow the mounting for your front mounted swirl pot please?
Thanks
Richardracer
richardracer said:
Hi Tom,
I forgot to ask, what sort of lap time improvement did you get with using slicks vs. AR/1 or similar track day tyres? Something we are thinking about, along with a fuel swirl,pot after getting surge, even with the 2 pump solution. Could you sow the mounting for your front mounted swirl pot please?
Thanks
Richardracer
Between the slicks and the AR1's around 1 or 2 seconds faster.I forgot to ask, what sort of lap time improvement did you get with using slicks vs. AR/1 or similar track day tyres? Something we are thinking about, along with a fuel swirl,pot after getting surge, even with the 2 pump solution. Could you sow the mounting for your front mounted swirl pot please?
Thanks
Richardracer
Swirl pot is a must on the E46, the two pump set up just doesn't work.
I have mine next to the fuse box
Cadwell Park April 2024.
Fresh off the trailer at 7:30, always find the morning of a trackday a little bit worrying, hoping everything is right with the car and that it's going to work, this would probably be made easier if I didn't change so many things between each day, but where is the fun in that?
The weather was totally unexpected, traveling over to Louth the previous day was shocking with torrential wind and rain, but following it was the lovely calm and sunny weather we were blessed with on Monday.
Went out for sighting laps and discovered a missfire above 3000rpm. Did a few checks thinking back over things I had changed prior to Cadwell, pulled out the laptop and checked the vanos was working correctly as I'd taken some time to change the base cam timing for the vanos cam position numbers were all positive to help with logging the cam timing for the inlet and exhaust, all seemed to work in the paddock but I had a suspicion it was related to this, popped on a older map with the same cam set up and tables as last time, low and behold the first session out it was running as normal, i'll get rid of the minus numbers in the logger code instead.
Suspension set up
Straight out of the box it was obvious how much of a difference the front antiroll bar change to the 30mm had on the handling of the car. It was so much flatter through the corners, there was much more grip on the front end and as a result of the flatter front end the drive out of the corners from increased rear grip was much improved. Finally felt like I'd gotten somewhere with it.
ABS - Refitting the MK60 with the addition of the bias valve between the MC and the ABS pump for the rear circuit.
This was the main change for the day which I wanted to do some work on figuring out, with a hope in the long run it will make the car faster.
First two morning sessions I ran the ABS as it is, nothing turned off and let the system do it's job to see what happened.
ABS/ASC/DSC completely on:
Above you can see the ABS working, detecting slip on the rear wheels and the line pressure to the rear circuit decreases. Only problem was you can see a little further along as the throttle position increases when wheel slip is detected under power it is applying the front and rear brakes. Less than ideal.
ABS still on ASC/DSC turned off using the switch - This could be short press or long press - forgot to make a note
ABS working as it should, upon detecting wheel slip it drops the rear line pressure everything working as it should.
However during one of the morning sessions I had two instances where the brake pedal went straight to the floor, once at the end of Park Straight and the second at Mansfield which resulted in a detour to the marshals hut up the hill. Both instances where two laps apart. Once it happened a second time I came in and gave the car a once over, checked for leaks, any warning lights or codes, checked fluid level. Couldn't find anything a miss at this point. Thought it was possibly down to the deceleration rate of the car using the onboard Yaw sensor and the brake pressures so went out for a session with the Yaw Sensor unplugged which disables the ASC/DSC completely.
Another reason for trying this was that I had noticed coming out of hall bends in 3rd gear, normally I drop into 2nd as it gets out the corner better there was a slightly bogging down, I thought it was still some form of intervention from the ASC/DSC, didn't really have time to sit at the laptop and go through all the logs on a trackday so decided to go with the yaw sensor unplugged and see how it felt.
ABS working as expected but noticed a drop in the maximum brake pressure I was able to get from the system, at the time I described it as though the ABS was holding me back and I had to push much harder to get the same braking effort. Notice the maximum braking pressure for this session was around 800psi rather than the 1000-1100psi I'd seen on previous sessions.
The car still bogged coming out of hall bends - Looked at the logs and found a rich spot on the map at 3500rpm and full throttle - Changes the fueling table and it started to clean up, needs a little more adjustment but can do that before going out again.
Just before lunch I gave the car another once over while there was a red flag. Jacked the car up and popped the wheels off.
What I did find explained the loss of brake pedal...
Rear pads disintegrating
Not just breaking down into little pieces, breaking away in big chunks, however these pads are quite old, I bought them in 2018, didn't run them during 2019 and refitted again in 2020. I have periodically checked them and they have looked ok but age, heat cycles and being exposed to moisture has taken it's toll.
Pads from the over side still looking good, luckily I had a spare set of rear pads in the van, popped these in and off I went again for a session before lunch.
Had manged to good 60miles on circuit in the morning, gathered a lot of information by this point and set about doing some decent sessions in the car in the afternoon, most of them being 25 minute plus.
Noticed a big difference in being strapped into the Sparco Circuit seat and the additional support it provides being a much deeper seat. There is more support under the thighs so you're sat further down deeper into the seat and don't move forward under braking and finally the additional shoulder support.
Covered in flies at the end of the day, 140+ miles later
Near Side Front slick took a beating even with the 3.6-3.8 degrees of camber. Going to do some work on this as really I need to be over 4 degrees of camber to get the most from them with this set up, watch this space...
Packed up and loaded at the end of the day, ready to go again with some tweaks.
Still not 100% happy with the ABS set up but this wasn't helped by the disintegrated rear pads and having to go back to standard rears. I did take it easy on the brakes in the afternoon and increase the braking distances which you'll probably notice in the videos.
Will order some new pads all around and continue with the Mk60 with the Yaw sensor plugged back in and DSC/ASC disabled, reading the manual this is also possible to do by unplugging the brake fluid level sensor - this will lead the ABS working fully with the Yaw sensor.
Video - Smoothest lap of the day - Happy to finally get down to a 1:40 lap time, Car will easily go into the 1:39's or less with new brake pads and start to get used to them again driving with ABS, took me a good number of back to back laps to get used to not completely lifting for Copice.
One of the afternoon sessions, I ended up lapping with a very equally paced Megane. Interesting to see the different areas both cars pick up pace on.
Still got a few bits to edit and look at but for now...
helix402 said:
I used to run an M3 Conv. front arb-27mm on all my E46s. Despite theory that it would increase understeer-it didnt. It reduced roll without a reduction in ride quality. This was on road cars, not track. I’m sure your 30mm bar will work well. If only BMW had made the E9x suspension as good as the E46!
You're right. There certainly wasn't any more under steer than I would normally have, really glad I decided to go down this route and test it out. Will try the firmer and softer settings are some point.Wouldn't it be great just to park up the car after a track day? Maybe give it a wash and leave it at that?
Started with washing wheels and giving everything a check over...
NSF tyre didn't fair that well at Cadwell even with approx 3.5 degrees of camber - I've ordered a digital level which I'm going to make/mount into a camber gauge to take some more accurate measurements this week.
OSF not as bad but still not wearing level - These tyres only had 2.6mm of material on them anyway. Cadwell was going to be a bit of a test to see how I got on with the tyres with my current alignment settings.
Also signs of the OSF demalminating at the edge.
Also found a bent ARB mount, all well and good making the car stiffer but the force has to go somewhere, found a weak link. Spoken to Gaz already and the dampers are going to go back to them for some new different designed ARB mounts and a service while they are there. This wasn't something I had planned, was going to double up the thickness of it myself but might as well get it sorted before it tears the bracket off the shock.
None bent one for reference. The bent side is the drivers side shock so will be getting maximum load around left hand corners - Possibly damaged around coppice?
Popped the splitter, front bumper and wings off the car to start to look at increasing the camber on the front
Top mounts are at their max in their current setting, and depending on what I find with the alignment this week I probably need to find about 0.5-0.7 degree extra
Taken some measurements and crunched some numbers. By my maths I need 11mm worth of additional movement on the top mounts to get up to an extra 1 degress of camber. Drilled some additional holes so I can build it back up and measure the camber change
The plan is going to be to cut some of the strut top away and plate over the top with some 5mm steel. Have already ordered some 150mm discs which I can machine with the following cut out. Planning to weld this over the strut top to strengthen it.
On the never ending list of things I want to do with the E46, I have had rusty wings written on there for a while. Deicded to do something about it. Where this is going to end I dont know!!
While I had them off I've ground away all the signs of surface rust, treated the surface and painted them with etch primer to start with
I have also cut away any tabs on the edge of the arch where the liners normally mount and wire wheeled all the inside of the arch for painting too to stop moisture starting to rust through from the back side,
Got as far as a skim of filler around the edge just to flatten out any of the low spots and marks from grinding.
Body work isn't something I would say I am amazing at, so far I've painted inside a few track cars and the quality is improving, painted wheels, mountain bikes and forks and the all spoiler, splitter and body kit for vans. Whether I decide to paint the wings we will see. Watch this space!
Hi Tom,
Try downloading free app called RC-Camber if you are an iPhone user. Glad you saw such an improvement with front 30mm arb. Makes such a difference.
Off to look at swirl pots to cure fuel surge below half full.
Plan to be at Cadwell on 21st June and Oulton Park on 15th Oct, just in case you are planning your track days.
Cheers
Richard Stok
Try downloading free app called RC-Camber if you are an iPhone user. Glad you saw such an improvement with front 30mm arb. Makes such a difference.
Off to look at swirl pots to cure fuel surge below half full.
Plan to be at Cadwell on 21st June and Oulton Park on 15th Oct, just in case you are planning your track days.
Cheers
Richard Stok
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