How prevalent is the #8 cylinder Issue?
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E55 w/ goods, Z32 Project underway
How prevalent is the #8 cylinder Issue?
Noticed the cylinder #8 issue has been brought up a few times. Curious what kind of damage has been reported, remedies, etc. Can this be adjusted in a tune? Higher flow injector for just this one cylinder?
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'03 E55, Range Rover Sport Supercharged, Ducati 748R
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Eurocharged 2004 E500, Eurocharged ECU/TCU 2005 SL600, 2010 Caddy SwaggerWagon
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E55 w/ goods, Z32 Project underway
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Thats what we found as well, and also why when we released our injector set, we had one injector flow more then the rest for #8
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2004 E55,1969 300SEL6.3,2011 ML350 BlueTec Diesel,2005 ML400 CDI
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2005 E55
Is it a cooling issue? I know some of the Ford V8's had a problem with no exit for the coolant in the back of the heads so they created a bypass to alleviate the problem. I believe it was the #8 cylinder as well..
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GL550, C55, 335i Coupe, vintage Mustang
The SLR has a single feed, with 2 fuel pressure regulators. I know it isn't a fantastic pic, but here is one of the rail. The coolant exit to the heater core is on the left bank at the back of the head, right behind the #8 cylinder, so I doubt that is the issue.
Nick
Nick
Last edited by nick 55; Sep 10, 2010 at 09:21 PM.
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Joined: May 2012
Posts: 306
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From: Melbourne, Australia
03 W211 E55
Hi
I know this is an older thread but where exactly is cylinder number 8 located?
Is it closest to the headlights or closest to the cabin of the car?
Using the US left hand drive car as an example is cylinder number 8 on the drivers side or passenger side?
---
Does anybody know if we install a wideband o2 sensor can we install it about 2 inches after the exhaust outlet of the head so we can get readings just for that cylinder only and be able to install and remove the wideband o2 sensor without getting underneath the car?
Regards,
OZZYAMG
I know this is an older thread but where exactly is cylinder number 8 located?
Is it closest to the headlights or closest to the cabin of the car?
Using the US left hand drive car as an example is cylinder number 8 on the drivers side or passenger side?
---
Does anybody know if we install a wideband o2 sensor can we install it about 2 inches after the exhaust outlet of the head so we can get readings just for that cylinder only and be able to install and remove the wideband o2 sensor without getting underneath the car?
Regards,
OZZYAMG
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Joined: Jun 2006
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'03 E55, Range Rover Sport Supercharged, Ducati 748R
Hi
I know this is an older thread but where exactly is cylinder number 8 located?
Is it closest to the headlights or closest to the cabin of the car?
Using the US left hand drive car as an example is cylinder number 8 on the drivers side or passenger side?
---
Does anybody know if we install a wideband o2 sensor can we install it about 2 inches after the exhaust outlet of the head so we can get readings just for that cylinder only and be able to install and remove the wideband o2 sensor without getting underneath the car?
Regards,
OZZYAMG
I know this is an older thread but where exactly is cylinder number 8 located?
Is it closest to the headlights or closest to the cabin of the car?
Using the US left hand drive car as an example is cylinder number 8 on the drivers side or passenger side?
---
Does anybody know if we install a wideband o2 sensor can we install it about 2 inches after the exhaust outlet of the head so we can get readings just for that cylinder only and be able to install and remove the wideband o2 sensor without getting underneath the car?
Regards,
OZZYAMG
The problem was determined to be the design of the fuel rail. Because the fuel inlet is closest to #8, the pressure is the lowest. When fuel requirements increase due to mods, a modified fuel rail is highly recommended.
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From: Orlando
1967 Pro Touring turbo LSX Camaro
What you'd want instead of a single WB would be an EGT gauge .
Hi
I know this is an older thread but where exactly is cylinder number 8 located?
Is it closest to the headlights or closest to the cabin of the car?
Using the US left hand drive car as an example is cylinder number 8 on the drivers side or passenger side?
---
Does anybody know if we install a wideband o2 sensor can we install it about 2 inches after the exhaust outlet of the head so we can get readings just for that cylinder only and be able to install and remove the wideband o2 sensor without getting underneath the car?
Regards,
OZZYAMG
I know this is an older thread but where exactly is cylinder number 8 located?
Is it closest to the headlights or closest to the cabin of the car?
Using the US left hand drive car as an example is cylinder number 8 on the drivers side or passenger side?
---
Does anybody know if we install a wideband o2 sensor can we install it about 2 inches after the exhaust outlet of the head so we can get readings just for that cylinder only and be able to install and remove the wideband o2 sensor without getting underneath the car?
Regards,
OZZYAMG
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Joined: May 2012
Posts: 306
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From: Melbourne, Australia
03 W211 E55
Hi
Ok thanks for the replies so far.
I would have liked it if I could monitor the afr's with particular attention to cylinder number 8 and have it connected to an all in one device that could log afr's and rpm for like a 60 second period as well.
I suppose I better learn about EGT sensor's.
So just to confirm in the US W211 E55's cylinder number 8 is the closest cylinder to the driver of the car?
Regards,
OZZYAMG
Ok thanks for the replies so far.
I would have liked it if I could monitor the afr's with particular attention to cylinder number 8 and have it connected to an all in one device that could log afr's and rpm for like a 60 second period as well.
I suppose I better learn about EGT sensor's.
So just to confirm in the US W211 E55's cylinder number 8 is the closest cylinder to the driver of the car?
Regards,
OZZYAMG
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Joined: Dec 2006
Posts: 1,124
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From: Florida-Germany-New York
2004 E55,1969 300SEL6.3,2011 ML350 BlueTec Diesel,2005 ML400 CDI
Hi
Ok thanks for the replies so far.
I would have liked it if I could monitor the afr's with particular attention to cylinder number 8 and have it connected to an all in one device that could log afr's and rpm for like a 60 second period as well.
I suppose I better learn about EGT sensor's.
So just to confirm in the US W211 E55's cylinder number 8 is the closest cylinder to the driver of the car?
Regards,
OZZYAMG
Ok thanks for the replies so far.
I would have liked it if I could monitor the afr's with particular attention to cylinder number 8 and have it connected to an all in one device that could log afr's and rpm for like a 60 second period as well.
I suppose I better learn about EGT sensor's.
So just to confirm in the US W211 E55's cylinder number 8 is the closest cylinder to the driver of the car?
Regards,
OZZYAMG
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'03 E55, Range Rover Sport Supercharged, Ducati 748R
Power peaks right at 125 F below peak EGT. Smokey Yunik, The Great God Of Combustion knew this. For years, competitors wondered why each header tube on his motors had an 1/8" hole with a plug. Yunick always ran 180F or higher thermostats as he knew heat (in the proper location) = energy.
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From: Texas
2003 CL55
I have tore down and or inspected over 25 blown motors now and have seen #8 go a lot but lot of times, but usually several other pistons will be damaged as well, just may not be so obvious. Lot of times, other pistons still hold compression but will have cracked lands. I have seen #7 and also #2 and #6 go a lot.
I do not see #8 as being a weak link to fix, but maybe just the piston that tends to go first, when you already have other issues. As mentioned, #8 may detonate first but it is rarly the only hole that detonates when #8 melts. We study the micro metals that show up on the valves of blown engines, to show how many holes had aluminum particles starting to come off of each piston. So even if you take #8 out of the loop to blow, we see other pistons only being mili seconds from going next.
Weak links once you add 100 RWHP. (I use that number, as it takes a lot more tuning, stronger parts, cooling, fuel and other heat removal mods.
1) stock piston ring gap is way to tight and heat builds up between rings and detonation can happen fast.
2) larger injectors needed and more tuning with that change, plus stock fuel rail and lines become undersized.
3) 3 valve heads need exhaust help with lot of added power.
4) fuel rail inlet is 5-6mm id only and on 90 deg location to rail.
5) managing iats takes a lot more work and remember that tight ring gap.
Just a few things I have noticed over the years.
I do not see #8 as being a weak link to fix, but maybe just the piston that tends to go first, when you already have other issues. As mentioned, #8 may detonate first but it is rarly the only hole that detonates when #8 melts. We study the micro metals that show up on the valves of blown engines, to show how many holes had aluminum particles starting to come off of each piston. So even if you take #8 out of the loop to blow, we see other pistons only being mili seconds from going next.
Weak links once you add 100 RWHP. (I use that number, as it takes a lot more tuning, stronger parts, cooling, fuel and other heat removal mods.
1) stock piston ring gap is way to tight and heat builds up between rings and detonation can happen fast.
2) larger injectors needed and more tuning with that change, plus stock fuel rail and lines become undersized.
3) 3 valve heads need exhaust help with lot of added power.
4) fuel rail inlet is 5-6mm id only and on 90 deg location to rail.
5) managing iats takes a lot more work and remember that tight ring gap.
Just a few things I have noticed over the years.
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E63 Biturbo, UPD Cold Air induction kit, UPD performance crank pulley and UPD adjustable rear suspension with ride height adjustment.
CL55 UPD Cold Air Boost kit, UPD 3000 stall converter, UPD 77mm SC clutched pulley and beltwrap kit, Custom long tubes, UPD crank pulley , UPD suspension kit, UPD SC pulley, Aux. HE, Trunk tank w/rule 2000 pump, Mezeire pump, UPD 5pc idler set, Aluminum rotor hats.
www.ultimatepd.com
instagram @ultimate_pd
facebook.com/ultimatepd
