Project "negative crankcase pressure" on its way
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Project "negative crankcase pressure" on its way
Have a feeling I'm the only one to work one of these things into an MB motor. Very common and effective in the domestic engine building world. The unit I'm using is a one off smaller unit from GZmotorsports who builds great pumps. The pump is designed to work in a street environment where it will see as much low RPM use as it will high RPM use. The inside has been coated and the wiper material has a longer life compared to the "all out race" type pumps offered by Moroso, Areospace, etc..
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I bench tested the pump up to 3500 RPM which is the max it will see with the pulley combo I'm using. It made just over 13" of vacuum which is good as I will be setting the relief valve for the crankcase at 7-8". The relief valve will be plumbed into the breather lines so that at max vacuum it will pull fresh air through the crankcase via the relief valve. At idle the crankcase will be sealed via the relief valve pulling about 2-3in vacuum.
I've got an adjustable idler pulley being made that has a gilmer pulley piggyback machined to it's face. Basically a custom copy of the gzmotorsports LS1 street/strip vacuum kit in the picture below only configured differently.
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Should have some pulleys sometime next week. My goals are 10+whp, dipstick staying where it should, no more weaping valve covers, clean intake charge, and above all something different. Wish me luck.
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[/IMG]I bench tested the pump up to 3500 RPM which is the max it will see with the pulley combo I'm using. It made just over 13" of vacuum which is good as I will be setting the relief valve for the crankcase at 7-8". The relief valve will be plumbed into the breather lines so that at max vacuum it will pull fresh air through the crankcase via the relief valve. At idle the crankcase will be sealed via the relief valve pulling about 2-3in vacuum.
I've got an adjustable idler pulley being made that has a gilmer pulley piggyback machined to it's face. Basically a custom copy of the gzmotorsports LS1 street/strip vacuum kit in the picture below only configured differently.
[IMG]
[/IMG]Should have some pulleys sometime next week. My goals are 10+whp, dipstick staying where it should, no more weaping valve covers, clean intake charge, and above all something different. Wish me luck.
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So road testing has shown the meth/H20 to be a sucess, I just have no solid # data to show in terms of A/F, WOT temps(iat prob broke), and HP/TQ #s. Maybe this weekend....
A good A to W intercooler is down the road for sure. Really just waiting for the "oh yeah thats how I'm doing it" idea to pop in my head. These ideas usually happen while drinking or after sex.
PWR barrel intercooler has been a thought. I'm currently excited about this vac setup as I saw almost 20whp on my old 454SS pickup with a moroso vacuum pump. That motor was built a little loose though.
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From: Philadelphia, PA
2008 A8L, 2002 996TT X50, 2009 X5
The dyno I've been using had a chevy 1500 pickup catch fire and melt straps and all a couple weeks back. I've been waiting for the "ok" to head over and get some dynos with the meth/H20 setup. Until then all I know is the brief runs I had showing the IAT temps at around 40ish degrees cooler, and the fact that I no longer can burn myself on the intake mani
So road testing has shown the meth/H20 to be a sucess, I just have no solid # data to show in terms of A/F, WOT temps(iat prob broke), and HP/TQ #s. Maybe this weekend....
A good A to W intercooler is down the road for sure. Really just waiting for the "oh yeah thats how I'm doing it" idea to pop in my head. These ideas usually happen while drinking or after sex. PWR barrel intercooler has been a thought. I'm currently excited about this vac setup as I saw almost 20whp on my old 454SS pickup with a moroso vacuum pump. That motor was built a little loose though.
So road testing has shown the meth/H20 to be a sucess, I just have no solid # data to show in terms of A/F, WOT temps(iat prob broke), and HP/TQ #s. Maybe this weekend....
A good A to W intercooler is down the road for sure. Really just waiting for the "oh yeah thats how I'm doing it" idea to pop in my head. These ideas usually happen while drinking or after sex.
PWR barrel intercooler has been a thought. I'm currently excited about this vac setup as I saw almost 20whp on my old 454SS pickup with a moroso vacuum pump. That motor was built a little loose though.Sorry for the "noob" question, but I don't know jack about the "domestic engine building world" - what is it about this that helps make more whp?
Last edited by c32AMG-DTM; Oct 8, 2008 at 06:27 PM.
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From: PNW
2001 E430
Didn't GregC try a barrel style intercooler with lackluster results? Is the PWR brand intercooler more efficient then the brand he ran or do they just have better sized units to fit in that space. I seem to remember GregC mentioning it was hard to find a decent intercooler to fit that space. Silence found a way to over come the space limitations and run a decent sized IC but I wouldn't want to cut into my car that much just to make something work.
Also do you have a way to adjust the tension on the belt to your crankcase pump? I'm looking forward to your results on that mod.
Also do you have a way to adjust the tension on the belt to your crankcase pump? I'm looking forward to your results on that mod.
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Didn't GregC try a barrel style intercooler with lackluster results? Is the PWR brand intercooler more efficient then the brand he ran or do they just have better sized units to fit in that space. I seem to remember GregC mentioning it was hard to find a decent intercooler to fit that space. Silence found a way to over come the space limitations and run a decent sized IC but I wouldn't want to cut into my car that much just to make something work.
Also do you have a way to adjust the tension on the belt to your crankcase pump? I'm looking forward to your results on that mod.
Also do you have a way to adjust the tension on the belt to your crankcase pump? I'm looking forward to your results on that mod.
The idler pulley is going to be attached to an ajustable tensioner arm so I'll have a little bit of play +/- an inch or so. I can pivot the adjustable tensioner arm 360 degrees as well, I'll try and find a picture of it.
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sounds like airplane
yah, i definitely don't mind cutting so much.
my set-up definitely keeps things cool(ish) but improvements can definitely be made.
I'm interested in how this works for you- but haven't had any issues with getting gunk in places i don't want it (through the blower) with my pcv set-up.
i'm really waiting for your dyno results though
my set-up definitely keeps things cool(ish) but improvements can definitely be made.
I'm interested in how this works for you- but haven't had any issues with getting gunk in places i don't want it (through the blower) with my pcv set-up.
i'm really waiting for your dyno results though
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Nothing noob about it. It's not something you see everyday, and I'm not sure if it's only seen on domestics..thats just where I've seen them used. In theory they work on all engines I've just never seen one on anything else. In terms of creating power they are many times used in forced induction and loose motors. With forced induction manifold psi, extra hp, etc creates more force on the combustion side of things creating extra pressure within the crankcase creating blowby and power loss due to the fact that the downstroke of the piston has to overcome the pressure in the crankcase. PCV systems don't seem to cut it many times or at least from what I've gathered. Creating a negative pressure will cancel out the need to overcome the pressure and many times assist in the stroke by improving ring seal, stroke, combustion. I guess you could look at it as equalizing the the pressures on each side of the piston maybe..a negative supercharger for the crankcase...I'm overtired and trying to type on my Iphone..
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AMG C43, 1999
Cool stuff. I have taken the breather tube that goes into the intake elbow and sees manifold vacuum. From there I have three ford heavy-duty PVC valves are conected to the valve covers so when the manifold pulls a vacuum it pulls a vacuum in the crankcase. If the vacumm drops at the manifold the valves shut. It has reduced oil use to nil and there is no more oil being pulled into the manifold.
WE used to run a set-up like this on my AMA supersport bikes and it resulted in a few extra HP, untill AMA decided it was cheating.
Jeff
WE used to run a set-up like this on my AMA supersport bikes and it resulted in a few extra HP, untill AMA decided it was cheating.
Jeff
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From: REHOBOTH BEACH DE
88-300CE TWIN TURBO, 99-C43, 05-G55K, 71-280SL, 94-E320 CAB, 08 CLK63 BLACK SERIES
Nothing noob about it. It's not something you see everyday, and I'm not sure if it's only seen on domestics..thats just where I've seen them used. In theory they work on all engines I've just never seen one on anything else. In terms of creating power they are many times used in forced induction and loose motors. With forced induction manifold psi, extra hp, etc creates more force on the combustion side of things creating extra pressure within the crankcase creating blowby and power loss due to the fact that the downstroke of the piston has to overcome the pressure in the crankcase. PCV systems don't seem to cut it many times or at least from what I've gathered. Creating a negative pressure will cancel out the need to overcome the pressure and many times assist in the stroke by improving ring seal, stroke, combustion. I guess you could look at it as equalizing the the pressures on each side of the piston maybe..a negative supercharger for the crankcase...I'm overtired and trying to type on my Iphone..
On my M103-12V TT the draw is from the cam cover to the intake box using the turbos as the "pump" to draw vacuum.
At low RPM/intake vacuum the draw is from the cam cover to the intake similar to how a stock PCV system works.
With high RPM/turbo boost the one way valve closes and the draw is from the turbo intakes pulling vacuum from the cam cover.
Most turbo installs neglect this easy to install but beneficial system.
Last edited by RBYCC; Oct 9, 2008 at 09:06 AM.
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88-300CE TWIN TURBO, 99-C43, 05-G55K, 71-280SL, 94-E320 CAB, 08 CLK63 BLACK SERIES
Nice setup! That looks awesome. Any idea how much vacuum that pulls? I like that idea better than manifold vacuum as it would build with RPM and power rather than drop vacuum like using manifold. Thats a reason I didn't like using my manifold vacuum as it was higher at idle low load conditions and less at high rpm load condtitions. The opposite of what I needed. Preblower at the TB on my car matches manifold vacuum and I really wanted to isolate the crankcase gases from the intake charge. Going post blower I had to checkvalve the system to keep from sending boost to the crankcase which only allowed it to be vented under boost conditions. Again the opposite of what I needed. I think if I was turbo or centri setup I would probalby go that route strictly for symplicity. I'm curious about how much vacuum your making with those snails? Also, any idea how much blowby the vacuum creates? Ever get a chance to look inside the intake mani or run a catch can? All in all she's a beaut!
The install is with a fully engineered circa 1991 kit from TurboTechnics in the UK.
The kits were made specifically for Hughes of Beaconsfield, an authorized UK Merc dealer for installation on new 124 series M103-12V and M104-24V engines.
They were well documented in the early nineties in the UK motoring press.
I think the simplistic crankcase pressure relief system is the reason why there are a few TurboTechnics cars running now with over 150K miles and the head never removed.
Boost is fixed at 7PSI, so there is not excessive pressure into the crankcase.
More you put in, the more that should come out.
Most domestics with superchargers at the minimum need a few breathers on the valve/vcam covers or else stuff begins to "pop".
I've also seen fittings welded on the collectors of headers piped to the valve/cam cover using the draw from the exhaust to create a vacuum.
There has always been a controversy about how much power the negative crankcase pressure system makes as it may be negated by a restrictive exhaust system.
Don't worry about making power numbers as the main purpose is engine longevity
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Pulleys/Breathertank/odd size belt in...
Got the pulleys today in the mail. They look great and I hope to get some time to install them along with the "impossible to find" gates serpentine belt K061247........took days to find this belt size. Gates page doesn't even show it. 124.7 inchs long to make up for the lager idler pulley I'm installing and the addition of the vaccum pump idler/drive pulley.
The idler/drive pulley is a 3.5in with a 14tooth gilmer machined to the face. The pump pulley is a 36 tooth just over 4.2in.
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Hacked up a catch can, threaded a breather filter to the top and threaded a fitting into the bottom for a vacuum line back to the inake port of the vaccum pump. This will help by allowing a little bit of oil to travel up to the pump during idle, low vacuum, low blowby situations that the car will see plenty of. It will insure the pump has some type of lubricating oil passing through and doesn't burn up the wipers.
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The idler/drive pulley is a 3.5in with a 14tooth gilmer machined to the face. The pump pulley is a 36 tooth just over 4.2in.
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[/IMG]Hacked up a catch can, threaded a breather filter to the top and threaded a fitting into the bottom for a vacuum line back to the inake port of the vaccum pump. This will help by allowing a little bit of oil to travel up to the pump during idle, low vacuum, low blowby situations that the car will see plenty of. It will insure the pump has some type of lubricating oil passing through and doesn't burn up the wipers.
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1999 C43 AMG
It's easy to do on a turbo install, but most overlook the need to reduce crankcase pressure.
On my M103-12V TT the draw is from the cam cover to the intake box using the turbos as the "pump" to draw vacuum.
At low RPM/intake vacuum the draw is from the cam cover to the intake similar to how a stock PCV system works.
With high RPM/turbo boost the one way valve closes and the draw is from the turbo intakes pulling vacuum from the cam cover.
Most turbo installs neglect this easy to install but beneficial system.
On my M103-12V TT the draw is from the cam cover to the intake box using the turbos as the "pump" to draw vacuum.
At low RPM/intake vacuum the draw is from the cam cover to the intake similar to how a stock PCV system works.
With high RPM/turbo boost the one way valve closes and the draw is from the turbo intakes pulling vacuum from the cam cover.
Most turbo installs neglect this easy to install but beneficial system.
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88-300CE TWIN TURBO, 99-C43, 05-G55K, 71-280SL, 94-E320 CAB, 08 CLK63 BLACK SERIES
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09 335i 03 CLK55 AMG
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This mod sucks....really.
Some forward movement. Got everything hacked, fab'd, and mounted. Used all stainless hardware and nice 10AN billet fittings for the lines. I'll get some better pictures of the entire system if anyone wants to do something similar. I've got the large 10AN line going from the large single breather port D.side valve cover into the intake/suction port of the pump. I have the two small breather lines plumbed into a T-fitting vacuum relief valve set to 7 inches for the moment. The catch can is mounted behind the P.side fog lamp which is the only place I have room left. Downside is that I'll have to remove the wheel every month to empty the tank. The upside is that its out of site but one good part is that the mini filter's fumes get quickly sucked up by the nearby air filter = no more smelly benz The catch can has a small vac line going from the bottom so that during low RPM low vacuum the pump will still pull a small amount of oil for lubrication.
Onto the news. Everything is running as planned the drive/idler pulley with the gilmer pulley in front needs a little more belt wrap as it slips a little once things speed up. That said, I can't pull anymore than about 7 maybe 9 inches of vacuum at the moment. Works for now. Probably mess with the idlers this spring to get some belt traction and get vacuum up to 10 or 12in in the upper rpms. No more pushed up dipstick, weaping valve covers, or smelly fumes. Once I hit the dyno I'll be able to see if the efficiency frees up any HP. I have a feeling its worth a few ponies driving it around, it's defenitly smoother throughout.
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The catch can has a small vac line going from the bottom so that during low RPM low vacuum the pump will still pull a small amount of oil for lubrication. Onto the news. Everything is running as planned
the drive/idler pulley with the gilmer pulley in front needs a little more belt wrap as it slips a little once things speed up. That said, I can't pull anymore than about 7 maybe 9 inches of vacuum at the moment. Works for now. Probably mess with the idlers this spring to get some belt traction and get vacuum up to 10 or 12in in the upper rpms. No more pushed up dipstick, weaping valve covers, or smelly fumes. Once I hit the dyno I'll be able to see if the efficiency frees up any HP. I have a feeling its worth a few ponies driving it around, it's defenitly smoother throughout. [IMG]
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nitro with those symptoms are you sure you havent cracked a ring land or fried some piston rings? from running to lean or to much Hp,
i got those symptoms and ripped my motor out, deamed it stuffed, it shouldnt blowby that much that it pushed the dipstick out, unless you bunged the breather or something?
what do your sparkplugs look like?
i got those symptoms and ripped my motor out, deamed it stuffed, it shouldnt blowby that much that it pushed the dipstick out, unless you bunged the breather or something?
what do your sparkplugs look like?
Last edited by c280_nz; Dec 6, 2008 at 12:24 AM.
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nitro with those symptoms are you sure you havent cracked a ring land or fried some piston rings? from running to lean or to much Hp,
i got those symptoms and ripped my motor out, deamed it stuffed, it shouldnt blowby that much that it pushed the dipstick out, unless you bunged the breather or something?
what do your sparkplugs look like?
i got those symptoms and ripped my motor out, deamed it stuffed, it shouldnt blowby that much that it pushed the dipstick out, unless you bunged the breather or something?
what do your sparkplugs look like?
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Thanks dude, appreciate it
Hope I'm getting a little camcorder for christmas so maybe I can get some video of dyno maybe come spring. It looks pretty cool spining with the gilmer belt and such. I'm just hoping the pump vanes will last as long as they are supposed to. Only $50 to rebuild so once a year would be acceptable for me.
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Very nicely done. Not sure of your catch can, but I've seen installs that run a hose from the catch can drain to an easily accessible location with a drain valve at the end. Might make draining the can a bit easier, and the hose volume actually adds capacity.
c280nz, what he's seeing is really common with FI cars. In my former life I used to have a 951, several turbo Saabs, and a 1.8T Audi, in all cases I saw owners that had issues with blowby due to inadequate/plugged PCV systems. My personal favorite is going WOT and blowing the dipstick out of the tube. I've seen this same approach used to fix the problem before, Nitrogen knows what he's doing.
c280nz, what he's seeing is really common with FI cars. In my former life I used to have a 951, several turbo Saabs, and a 1.8T Audi, in all cases I saw owners that had issues with blowby due to inadequate/plugged PCV systems. My personal favorite is going WOT and blowing the dipstick out of the tube. I've seen this same approach used to fix the problem before, Nitrogen knows what he's doing.
