Has anyone ever successfully installed an SL55 SC onto the M112?
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Has anyone ever successfully installed an SL55 SC onto the M112?
Probably a right PITA.....
however....too much time on my hands sitting in dingy hotel rooms for work away from home.
I did a transparent plan image overlay of the two to see just how much bigger it is.
I'm assuming the webbing pattern on the outer casing would be proprietary and hence of similar dimensions.
So
The rotor body seems to be about 27% longer (14 webbings against 11)
The Intake ports must line up 'cause RobertAMG fitted one to his M112
The gear housing at the front is much longer and RobAMG had to fit an additional crank arrangement.
Why you might ask....?
2.3L/1.6L increase in boost - so >20psi
It may run more efficiently at these levels = cooler, less crank drain.
Just throwing it out there.
however....too much time on my hands sitting in dingy hotel rooms for work away from home.
I did a transparent plan image overlay of the two to see just how much bigger it is.
I'm assuming the webbing pattern on the outer casing would be proprietary and hence of similar dimensions.
So
The rotor body seems to be about 27% longer (14 webbings against 11)
The Intake ports must line up 'cause RobertAMG fitted one to his M112
The gear housing at the front is much longer and RobAMG had to fit an additional crank arrangement.
Why you might ask....?
2.3L/1.6L increase in boost - so >20psi
It may run more efficiently at these levels = cooler, less crank drain.
Just throwing it out there.
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Re: Has anyone ever successfully installed an SL55 SC onto the M112?
Here's a gif I prepared of the overlay from RobertAMG's post over here
Best open it in a seperate window and enlarge to 400%.
The cylinder pitch is obviously okay as mentioned previously.
Robert made the comment that he reused the cooler from the C32.
Best open it in a seperate window and enlarge to 400%.
The cylinder pitch is obviously okay as mentioned previously.
Robert made the comment that he reused the cooler from the C32.
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Re: Has anyone ever successfully installed an SL55 SC onto the M112?
If it's been done before, it can be done again. I like the idea myself because this little engine can obviously take more than were asking of it. Not to mention how lazy (i.e. cool) it would turn to make the same power as our 1.6 liter.
Les
Les
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Re: Has anyone ever successfully installed an SL55 SC onto the M112?
Well Xfire owners - you are a tad luckier. The M113 can fit into your engine bay.
SLK32 owners arent as blessed unfortunately.
SLK32 owners arent as blessed unfortunately.
Last edited by Billy22Bob; Nov 2, 2013 at 02:29 PM.
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Re: Has anyone ever successfully installed an SL55 SC onto the M112?
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Re: Has anyone ever successfully installed an SL55 SC onto the M112?
then work out:
1) how the intercooler>Y piece> plenums need to be moded to fit,
2) how the TB>Intake Y-piece>filters can be fitted.
RobertAMG had a hell of a job trying to fit the TB>Y-piece 'cause it hit the back fire wall requiring him to change the wiper assembly somehow and stick his intake filter over the back in the engine bay.
A bonnet scoop incorporating filter might help here.
- fortunately an R170 SLK bonnet wouldnt be too expensive as a spare for modding, probably the same for SRT's.
Needs to be pieced together.
Regardless, initially you could pulley it down so that you got <18psi from the 2.3L SC and keep your injectors/fuel stock for intial testing then pulley up into the stratosphere.
On that vane.....
Questions; If anyone can help -
1) I noticed over at NW - the SL55 crank pulley dampner has two belt grooves - which ones the SC and which ones the ancilliaries? Dimensions?
innner....mm
outer.....mm
2) what's the stock SL55 SC pulley mm?.....
I think it would be better to simply keep with the a single belt run, but if you can fit an additional belt from crank>SC without clashing and requiring idlers etc...that would allow the SC to be moved 30mm forward - it may be necessary. Getting around the Water pump might be the biggest worry.
Will see.....
TIA
updated later with jpg of "scaled" dimensions I could glean from my SC
Last edited by Billy22Bob; Nov 4, 2013 at 02:46 AM.
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Re: Has anyone ever successfully installed an SL55 SC onto the M112?
Still trying to get my head around the 1.6L SC v the 2.3L SC, their internal gearing, mesh and subsequently their various rotor rpm.
You can tell by the many fotos on the web that the 2.3L has an internal gearing system which apparently takes your pulley ratio
2:1? and cranks at least one of the rotors up to a reported 23,000rpm. (If anyone knows the stock ratio for an SL55 - much appreciated)
I can only guess that if one has 3 lobes but the other has 5 "concaves"- I'm guessing they spin at different speeds - the 5Xconcave rotor would spin at 3/5ths of the speed of the 3 lober.
But still cant get my head around (visualise) these two spinning at different rpm....- I guess other gears do.....oh wise ones please chime in.
This also applies to the little brother - the 1.6L SC
Now the 1.6L SC has some form of gearing (difficult to find exploded view photos of the 1.6L) but in this case I believe (at least) one rotor spins at SC pulley speed (direct drive?) and I guess the other one spins at 5/3 or 3/5 that rpm.
thoughts?....
You can tell by the many fotos on the web that the 2.3L has an internal gearing system which apparently takes your pulley ratio
2:1? and cranks at least one of the rotors up to a reported 23,000rpm. (If anyone knows the stock ratio for an SL55 - much appreciated)
I can only guess that if one has 3 lobes but the other has 5 "concaves"- I'm guessing they spin at different speeds - the 5Xconcave rotor would spin at 3/5ths of the speed of the 3 lober.
But still cant get my head around (visualise) these two spinning at different rpm....- I guess other gears do.....oh wise ones please chime in.
This also applies to the little brother - the 1.6L SC
Now the 1.6L SC has some form of gearing (difficult to find exploded view photos of the 1.6L) but in this case I believe (at least) one rotor spins at SC pulley speed (direct drive?) and I guess the other one spins at 5/3 or 3/5 that rpm.
thoughts?....
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From: Ontario
Re: Has anyone ever successfully installed an SL55 SC onto the M112?
Still trying to get my head around the 1.6L SC v the 2.3L SC, their internal gearing, mesh and subsequently their various rotor rpm.
You can tell by the many fotos on the web that the 2.3L has an internal gearing system which apparently takes your pulley ratio
2:1? and cranks at least one of the rotors up to a reported 23,000rpm. (If anyone knows the stock ratio for an SL55 - much appreciated)
I can only guess that if one has 3 lobes but the other has 5 "concaves"- I'm guessing they spin at different speeds - the 5Xconcave rotor would spin at 3/5ths of the speed of the 3 lober.
But still cant get my head around (visualise) these two spinning at different rpm....- I guess other gears do.....oh wise ones please chime in.
This also applies to the little brother - the 1.6L SC
Now the 1.6L SC has some form of gearing (difficult to find exploded view photos of the 1.6L) but in this case I believe (at least) one rotor spins at SC pulley speed (direct drive?) and I guess the other one spins at 5/3 or 3/5 that rpm.
thoughts?....
You can tell by the many fotos on the web that the 2.3L has an internal gearing system which apparently takes your pulley ratio
2:1? and cranks at least one of the rotors up to a reported 23,000rpm. (If anyone knows the stock ratio for an SL55 - much appreciated)
I can only guess that if one has 3 lobes but the other has 5 "concaves"- I'm guessing they spin at different speeds - the 5Xconcave rotor would spin at 3/5ths of the speed of the 3 lober.
But still cant get my head around (visualise) these two spinning at different rpm....- I guess other gears do.....oh wise ones please chime in.
This also applies to the little brother - the 1.6L SC
Now the 1.6L SC has some form of gearing (difficult to find exploded view photos of the 1.6L) but in this case I believe (at least) one rotor spins at SC pulley speed (direct drive?) and I guess the other one spins at 5/3 or 3/5 that rpm.
thoughts?....
35 teeth (5 lobes) and 21 teeth (3 lobes), so the 5 lobe rotates 1.666 (35/21) times as fast as the 3 lobes. As you say a gear is a gear and the lobes mesh so ....... they rotate at different speeds.
The 35 tooth gear rotates the same speed as the pulley.
I got these great photos of some forum, and I have lost that info. My apologies to the photographer, I believe it was a MB forum with a lot of info on his rebuild of a SC. If I can find the info I will give credit.
Last edited by onehundred80; Nov 9, 2013 at 08:51 PM. Reason: modified to correct obvious error, not to me though. LOL
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Re: Has anyone ever successfully installed an SL55 SC onto the M112?
inner is 6 rib, outer (SC driver) is 8 rib
2) 90 or 91 depending on whom you ask .... but I just measured one sitting on my desk and it is 91mm
cheers,
Chris
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Re: Has anyone ever successfully installed an SL55 SC onto the M112?
Cool - thanks all.
Here's the 2.3L summary for anyone who cares to know.
apart from all the other intricacies around compression efficiencies - just getting such a large odd and hollow shape to be balanced at 23,000rpm would be a challenge in its self.
PS - Photo courtesy of Kanters link - but I've taken his main drive gear (46 tooth) and mirrored it and then rotated 180deg to overlay.
b22b
Here's the 2.3L summary for anyone who cares to know.
apart from all the other intricacies around compression efficiencies - just getting such a large odd and hollow shape to be balanced at 23,000rpm would be a challenge in its self.
PS - Photo courtesy of Kanters link - but I've taken his main drive gear (46 tooth) and mirrored it and then rotated 180deg to overlay.
b22b
Last edited by Billy22Bob; Nov 7, 2013 at 08:16 AM.
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Re: Has anyone ever successfully installed an SL55 SC onto the M112?
I just went and revised the dimension check on the 2 units (attached)
something to consider given the last 2 posts.
The breadth of the units is similarso one could assume the rotors to be similar diameters and dare I say - shape. I'd figure from a manufacturing standpoint they are probably cast the same and the 1.6L unit is simply cut off shorter.
Looking at my guesometric diemnsions of the 2.3L body when scaled from the actual dimensions of the 1.6L on my vehicle, the rotor case is 278mm long against 220mm = 26% longer
1.26 x 1.6L = 2.02L - so you'd need an additional 14% speed to get to the 2.3L.
That's assuming of course the 1.6L and 2.3L is confirmed - I havent been able to do that as yet.
IHI isentropic charts for the "2.3L" are nigh impossible to find. The assumption everywhere is to just use the Lysholm charts.
Assuming similar casting/balance/manufacturing processes - if we can check out the bearings for the 2.3L which are obviously good for 23,000rpm on the 3 lober, I would be suprised ours is very different - but we only run our 3 lobe shaft at 15,000rpm.....hmmmmm....interesting.
L8tr....The internal gearing on the 2.3L seems a bit unnecessary really - maybe for the purposes of what I am looking at here - the front gearing arrangement of the 1.6L could be fitted to the 2.3L lobes and simply spun with a 62mm pulley. Same end game - but you dont have this longer snout - given we are pushed for room.
given upping the kWs transfered - slip may become more of an issue - but saves a whole 2nd belt and pulley complication.
Apologies for those who - have heard it all before.
something to consider given the last 2 posts.
The breadth of the units is similarso one could assume the rotors to be similar diameters and dare I say - shape. I'd figure from a manufacturing standpoint they are probably cast the same and the 1.6L unit is simply cut off shorter.
Looking at my guesometric diemnsions of the 2.3L body when scaled from the actual dimensions of the 1.6L on my vehicle, the rotor case is 278mm long against 220mm = 26% longer
1.26 x 1.6L = 2.02L - so you'd need an additional 14% speed to get to the 2.3L.
That's assuming of course the 1.6L and 2.3L is confirmed - I havent been able to do that as yet.
IHI isentropic charts for the "2.3L" are nigh impossible to find. The assumption everywhere is to just use the Lysholm charts.
Assuming similar casting/balance/manufacturing processes - if we can check out the bearings for the 2.3L which are obviously good for 23,000rpm on the 3 lober, I would be suprised ours is very different - but we only run our 3 lobe shaft at 15,000rpm.....hmmmmm....interesting.
L8tr....The internal gearing on the 2.3L seems a bit unnecessary really - maybe for the purposes of what I am looking at here - the front gearing arrangement of the 1.6L could be fitted to the 2.3L lobes and simply spun with a 62mm pulley. Same end game - but you dont have this longer snout - given we are pushed for room.
given upping the kWs transfered - slip may become more of an issue - but saves a whole 2nd belt and pulley complication.
Apologies for those who - have heard it all before.
Last edited by Billy22Bob; Nov 7, 2013 at 05:50 PM.
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Re: Has anyone ever successfully installed an SL55 SC onto the M112?
Since these are 'positive' displacement blowers, spinning them faster does not increase the amount of air moved per revolution.
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Re: Has anyone ever successfully installed an SL55 SC onto the M112?
So if we are running the 3 lober directly from the the SC pulley at 15,000rpm - then the 5 lober is running at 3/5ths that speed or 9,000rpm - unless I am missing something.
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Re: Has anyone ever successfully installed an SL55 SC onto the M112?
The way I look at it - the 3 lober is on the shaft of the 21 tooth gear (front right) and the 35 tooth is on the shaft of the 5 lober (front left).
So if we are running the 3 lober directly from the the SC pulley at 15,000rpm - then the 5 lober is running at 3/5ths that speed or 9,000rpm - unless I am missing something.
So if we are running the 3 lober directly from the the SC pulley at 15,000rpm - then the 5 lober is running at 3/5ths that speed or 9,000rpm - unless I am missing something.
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Re: Has anyone ever successfully installed an SL55 SC onto the M112?
Some pics to show others what you are talking about.
35 teeth (5 lobes) and 21 teeth (3 lobes), so the 5 lobe rotates .60 (21/35) times as fast as the 3 lobes. As you say a gear is a gear and the lobes mesh so ....... they rotate at different speeds.
The 21 tooth gear rotates the same speed as the pulley.
I got these great photos of some forum, and I have lost that info. My apologies to the photographer, I believe it was a MB forum with a lot of info on his rebuild of a SC. If I can find the info I will give credit.
35 teeth (5 lobes) and 21 teeth (3 lobes), so the 5 lobe rotates .60 (21/35) times as fast as the 3 lobes. As you say a gear is a gear and the lobes mesh so ....... they rotate at different speeds.
The 21 tooth gear rotates the same speed as the pulley.
I got these great photos of some forum, and I have lost that info. My apologies to the photographer, I believe it was a MB forum with a lot of info on his rebuild of a SC. If I can find the info I will give credit.
We are both sort of wrong....
At stock pulley ratios
Where you said "The 21 tooth gear rotates the same speed as the pulley."
For the 1.6L - the 35 tooth (connected to the 5 lober) is actually driven by the pulley at 12,986rpm
and the teflon coated rotor is then spun at 21,644rpm via the internal gearing.
For the 2.3L - the internal gearing spins the 5 lober to 14,288rpm or 10% faster and subsequently
the teflon coated rotor is then spun at the much touted 23,813rpm.
This might be a surprise to some - the 1.6L is spinning at almost the same speed as the 2.3L.
This also lines up with my other observation and that is the two kits are very similar in profile.
I would guess they are identical in shape, but the 1.6L rotors are cut shorter for the shorter motor.
This is a crap paragraph but instead of deleting will grey out - they dont seem to offer a strike through.
"- but I'll I'll approach it from the 2.3L angle.
How much longer are the 2.3L rotors?
I dont have a 2.3L on hand but based up on my scale drawing in the previous post - the 2.3L about 278/220mm = 26% longer
Given it spins at 10% faster and is 26% longer - 1.6L x 1.1 x 1.26 = 2.2L - close and I'll take a cigar when the true 278mm length is verified..."
and corrected in a subsequent following post.
So - my target is now to establish if the gearing snouts are interchangeable."- but I'll I'll approach it from the 2.3L angle.
How much longer are the 2.3L rotors?
I dont have a 2.3L on hand but based up on my scale drawing in the previous post - the 2.3L about 278/220mm = 26% longer
Given it spins at 10% faster and is 26% longer - 1.6L x 1.1 x 1.26 = 2.2L - close and I'll take a cigar when the true 278mm length is verified..."
and corrected in a subsequent following post.
Given some (like Guran over at mbworld here) have the SC pulley spinning at 65/185 x 6200rpm = 17,650rpm and hence the 3 lober is actually spinning at 29,410rpm!.....literally screaming...(well that's always a relative term), and dont seem to suffer from belt slip to any significant degree, we can obviously spin these babies fast.
If we can interchange the snout from the 1.6L onto the 2.3L Rotors and body, then we get the extra 26% length, without the complexity of having to run a second belt.
We can then run the SC at a lower speed for the same volume and possibly improve the efficiencies somewhat....TBA on that comment.
There is still the pro blem of actually fitting the cooler> intakes etc to the longer charger...but that's another challenge.
b22b
Last edited by Billy22Bob; Nov 9, 2013 at 11:33 PM.
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Re: Has anyone ever successfully installed an SL55 SC onto the M112?
We are both sort of wrong....
At stock pulley ratios
Where you said "The 21 tooth gear rotates the same speed as the pulley."
For the 1.6L - the 35 tooth (connected to the 5 lober) is actually driven by the pulley at 12,986rpm
and the teflon coated rotor is then spun at 21,644rpm via the internal gearing.
For the 2.3L - the internal gearing spins the 5 lober to 14,288rpm or 10% faster and subsequently
the teflon coated rotor is then spun at the much touted 23,813rpm.
This might be a surprise to some - the 1.6L is spinning at almost the same speed as the 2.3L.
This also lines up with my other observation and that is the two kits are very similar in profile.
I would guess they are identical in shape, but the 1.6L rotors are cut shorter for the shorter motor.
I'll approach it from the 2.3L angle.
How much longer are the 2.3L rotors?
I dont have a 2.3L on hand but based up on my scale drawing in the previous post - the 2.3L about 278/220mm = 26% longer
Given it spins at 10% faster and is 26% longer - 1.6L x 1.1 x 1.26 = 2.2L - close and I'll take a cigar when the true 278mm length is verified.
So - my target is now to establish if the gearing snouts are interchangeable.
Given some (like Guran over at mbworld here) have the SC pulley spinning at 65/185 x 6200rpm = 17,650rpm and hence the 3 lober is actually spinning at 29,410rpm!.....literally screaming...(well that's always a relative term), and dont seem to suffer from belt slip to any significant degree, we can obviously spin these babies fast.
If we can interchange the snout from the 1.6L onto the 2.3L Rotors and body, then we get the extra 26% length, without the complexity of having to run a second belt.
We can then run the SC at a lower speed for the same volume and possibly improve the efficiencies somewhat....TBA on that comment.
There is still the pro blem of actually fitting the cooler> intakes etc to the longer charger...but that's another challenge.
b22b
At stock pulley ratios
Where you said "The 21 tooth gear rotates the same speed as the pulley."
For the 1.6L - the 35 tooth (connected to the 5 lober) is actually driven by the pulley at 12,986rpm
and the teflon coated rotor is then spun at 21,644rpm via the internal gearing.
For the 2.3L - the internal gearing spins the 5 lober to 14,288rpm or 10% faster and subsequently
the teflon coated rotor is then spun at the much touted 23,813rpm.
This might be a surprise to some - the 1.6L is spinning at almost the same speed as the 2.3L.
This also lines up with my other observation and that is the two kits are very similar in profile.
I would guess they are identical in shape, but the 1.6L rotors are cut shorter for the shorter motor.
I'll approach it from the 2.3L angle.
How much longer are the 2.3L rotors?
I dont have a 2.3L on hand but based up on my scale drawing in the previous post - the 2.3L about 278/220mm = 26% longer
Given it spins at 10% faster and is 26% longer - 1.6L x 1.1 x 1.26 = 2.2L - close and I'll take a cigar when the true 278mm length is verified.
So - my target is now to establish if the gearing snouts are interchangeable.
Given some (like Guran over at mbworld here) have the SC pulley spinning at 65/185 x 6200rpm = 17,650rpm and hence the 3 lober is actually spinning at 29,410rpm!.....literally screaming...(well that's always a relative term), and dont seem to suffer from belt slip to any significant degree, we can obviously spin these babies fast.
If we can interchange the snout from the 1.6L onto the 2.3L Rotors and body, then we get the extra 26% length, without the complexity of having to run a second belt.
We can then run the SC at a lower speed for the same volume and possibly improve the efficiencies somewhat....TBA on that comment.
There is still the pro blem of actually fitting the cooler> intakes etc to the longer charger...but that's another challenge.
b22b
I am erasing that post as I cannot be bothered to correct it again.
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Re: Has anyone ever successfully installed an SL55 SC onto the M112?
We are both sort of wrong....
At stock pulley ratios
Where you said "The 21 tooth gear rotates the same speed as the pulley."
For the 1.6L - the 35 tooth (connected to the 5 lober) is actually driven by the pulley at 12,986rpm
and the teflon coated rotor is then spun at 21,644rpm via the internal gearing.
For the 2.3L - the internal gearing spins the 5 lober to 14,288rpm or 10% faster and subsequently
the teflon coated rotor is then spun at the much touted 23,813rpm.
This might be a surprise to some - the 1.6L is spinning at almost the same speed as the 2.3L.
This also lines up with my other observation and that is the two kits are very similar in profile.
I would guess they are identical in shape, but the 1.6L rotors are cut shorter for the shorter motor.
I'll approach it from the 2.3L angle.
How much longer are the 2.3L rotors?
I dont have a 2.3L on hand but based up on my scale drawing in the previous post - the 2.3L about 278/220mm = 26% longer
Given it spins at 10% faster and is 26% longer - 1.6L x 1.1 x 1.26 = 2.2L - close and I'll take a cigar when the true 278mm length is verified.
So - my target is now to establish if the gearing snouts are interchangeable.
Given some (like Guran over at mbworld here) have the SC pulley spinning at 65/185 x 6200rpm = 17,650rpm and hence the 3 lober is actually spinning at 29,410rpm!.....literally screaming...(well that's always a relative term), and dont seem to suffer from belt slip to any significant degree, we can obviously spin these babies fast.
If we can interchange the snout from the 1.6L onto the 2.3L Rotors and body, then we get the extra 26% length, without the complexity of having to run a second belt.
We can then run the SC at a lower speed for the same volume and possibly improve the efficiencies somewhat....TBA on that comment.
There is still the pro blem of actually fitting the cooler> intakes etc to the longer charger...but that's another challenge.
b22b
At stock pulley ratios
Where you said "The 21 tooth gear rotates the same speed as the pulley."
For the 1.6L - the 35 tooth (connected to the 5 lober) is actually driven by the pulley at 12,986rpm
and the teflon coated rotor is then spun at 21,644rpm via the internal gearing.
For the 2.3L - the internal gearing spins the 5 lober to 14,288rpm or 10% faster and subsequently
the teflon coated rotor is then spun at the much touted 23,813rpm.
This might be a surprise to some - the 1.6L is spinning at almost the same speed as the 2.3L.
This also lines up with my other observation and that is the two kits are very similar in profile.
I would guess they are identical in shape, but the 1.6L rotors are cut shorter for the shorter motor.
I'll approach it from the 2.3L angle.
How much longer are the 2.3L rotors?
I dont have a 2.3L on hand but based up on my scale drawing in the previous post - the 2.3L about 278/220mm = 26% longer
Given it spins at 10% faster and is 26% longer - 1.6L x 1.1 x 1.26 = 2.2L - close and I'll take a cigar when the true 278mm length is verified.
So - my target is now to establish if the gearing snouts are interchangeable.
Given some (like Guran over at mbworld here) have the SC pulley spinning at 65/185 x 6200rpm = 17,650rpm and hence the 3 lober is actually spinning at 29,410rpm!.....literally screaming...(well that's always a relative term), and dont seem to suffer from belt slip to any significant degree, we can obviously spin these babies fast.
If we can interchange the snout from the 1.6L onto the 2.3L Rotors and body, then we get the extra 26% length, without the complexity of having to run a second belt.
We can then run the SC at a lower speed for the same volume and possibly improve the efficiencies somewhat....TBA on that comment.
There is still the pro blem of actually fitting the cooler> intakes etc to the longer charger...but that's another challenge.
b22b
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Re: Has anyone ever successfully installed an SL55 SC onto the M112?
Copy of my other susbequent post over at mbworld.
I've had a look at the two supercharger gearings.
I've often read about the 2.3L lysholm doing 23,000rpm.
Well that's partly correct - half of it is - on stock pulleys SL55 of 155/91mm and at 6200rpm x 2 internal gears of 1.35 x 1.66 = 23,813 - that's for the 3 lobe rotor.
What I've termed the "cavity" rotor, is ony doing 3/5ths of that = 14,288rpm.
Suprisingly what I've worked out (apologies to those who already knew)
The 1.6L is doing similar speeds.
In stock format - 155/74m pulleys @6,200rpm the cavity rotor is the pulley driven rotor is doing 12,986rpm and the 3 lobe rotor is doing 5/3rds of that = 21,644rpm.
Of course in Guran's case for a 185/65mm = 17,646/29,410 rpm.
Although it is purely a relative term - that's some serious rpm!
The other thing I'm still trying to work out is the relative differences in the dimensions. I suspect the 2 compressors use the same rotors - but the 1.6L rotors are cut shorter to suit the shorter V6 blocks.
(If anyone has some info on this, much appreciated)
I currently working on the assumption the LYS2300 isentorpic chart floating around the web refers to pulley'd rpm and some sort of base m3/min - either STP or NTP.
What I was hoping for was.....
Coming at it from another angle - Well I've never pulled one apart - but measuring the cases, the 1.6L casing on my car is 220mm and if you look at the attached dimensional comparison, compliments of RobertAMG, and scale up by pixles - the 2.3L is 278mm or 26% longer.
Someone with an actual measurement appreciated.
So I guess you can say - work in progress....but some interesting revelations just the same (against other things I've read out there).
PS - also note the teflon coated rotor is on different sides for each application.
I've had a look at the two supercharger gearings.
I've often read about the 2.3L lysholm doing 23,000rpm.
Well that's partly correct - half of it is - on stock pulleys SL55 of 155/91mm and at 6200rpm x 2 internal gears of 1.35 x 1.66 = 23,813 - that's for the 3 lobe rotor.
What I've termed the "cavity" rotor, is ony doing 3/5ths of that = 14,288rpm.
Suprisingly what I've worked out (apologies to those who already knew)
The 1.6L is doing similar speeds.
In stock format - 155/74m pulleys @6,200rpm the cavity rotor is the pulley driven rotor is doing 12,986rpm and the 3 lobe rotor is doing 5/3rds of that = 21,644rpm.
Of course in Guran's case for a 185/65mm = 17,646/29,410 rpm.
Although it is purely a relative term - that's some serious rpm!
The other thing I'm still trying to work out is the relative differences in the dimensions. I suspect the 2 compressors use the same rotors - but the 1.6L rotors are cut shorter to suit the shorter V6 blocks.
(If anyone has some info on this, much appreciated)
I currently working on the assumption the LYS2300 isentorpic chart floating around the web refers to pulley'd rpm and some sort of base m3/min - either STP or NTP.
If you drive the 1.6L at 10,000rpm, the cavity rotor is turning at 10,000rpm - its directly driven by the pulley drive.
Now the LYS1600 doesnt directly have rpm on it. I'm only infering it is the line that goes through ~16m3/min (564cfm) at PR1.0 which at 10,000rpm = 1.6L/rev. Alterntate/additional information appreciated.
If you drive the 2.3L at 10,000rpm, based on the chart and extrapolating down to Pressure ratio of 1.0 you get 22.5m3/min or 794cfm or....2.25L/pulley rev at 100% Volumetric Eff..That's the deisgn specified volumetric capacity.
However, the "cavity" rotor is actually turning at 13,544. If you actually divide it by the cavity rotor's rpm - this points to 22,500Litres/min at 13,544 rpm or, 1.66L/rev of the rotor.
hmmm....this is only 4% more than the 1.6L unit.
...not exactly what I was looking for. If the rotors are the same profile (assumption only) then the 2.3L rotors must be about 4% longer.Now the LYS1600 doesnt directly have rpm on it. I'm only infering it is the line that goes through ~16m3/min (564cfm) at PR1.0 which at 10,000rpm = 1.6L/rev. Alterntate/additional information appreciated.
If you drive the 2.3L at 10,000rpm, based on the chart and extrapolating down to Pressure ratio of 1.0 you get 22.5m3/min or 794cfm or....2.25L/pulley rev at 100% Volumetric Eff..That's the deisgn specified volumetric capacity.
However, the "cavity" rotor is actually turning at 13,544. If you actually divide it by the cavity rotor's rpm - this points to 22,500Litres/min at 13,544 rpm or, 1.66L/rev of the rotor.
hmmm....this is only 4% more than the 1.6L unit.
What I was hoping for was.....
Coming at it from another angle - Well I've never pulled one apart - but measuring the cases, the 1.6L casing on my car is 220mm and if you look at the attached dimensional comparison, compliments of RobertAMG, and scale up by pixles - the 2.3L is 278mm or 26% longer.
Someone with an actual measurement appreciated.
So I guess you can say - work in progress....but some interesting revelations just the same (against other things I've read out there).
PS - also note the teflon coated rotor is on different sides for each application.
