Boost Data Log
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MBWorld Fanatic!
Joined: Jul 2014
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2005 e55 AMG
Boost Data Log
Trying to figure out why boost always peaks at 5,000 rpm or so and then tapers off 1-1.5 lower by red line. So a peak of 16.5-17lb's then slowly drops to 15-16.
Have been data logging every single run and it is always the same. I am getting some belt slip but don't think it's that because of the way it drops as it woiuld show a more jagged trace signal.
I have an independent analog input sensor on my data logger to read boost so it is very accurate and quick.
Anyone pay attention to there boost readings ??
Have been data logging every single run and it is always the same. I am getting some belt slip but don't think it's that because of the way it drops as it woiuld show a more jagged trace signal.
I have an independent analog input sensor on my data logger to read boost so it is very accurate and quick.
Anyone pay attention to there boost readings ??
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From: SOCAL
2004 E55
Trying to figure out why boost always peaks at 5,000 rpm or so and then tapers off 1-1.5 lower by red line. So a peak of 16.5-17lb's then slowly drops to 15-16.
Have been data logging every single run and it is always the same. I am getting some belt slip but don't think it's that because of the way it drops as it woiuld show a more jagged trace signal.
I have an independent analog input sensor on my data logger to read boost so it is very accurate and quick.
Anyone pay attention to there boost readings ??
Have been data logging every single run and it is always the same. I am getting some belt slip but don't think it's that because of the way it drops as it woiuld show a more jagged trace signal.
I have an independent analog input sensor on my data logger to read boost so it is very accurate and quick.
Anyone pay attention to there boost readings ??
Thread Starter
MBWorld Fanatic!
Joined: Jul 2014
Posts: 3,331
Likes: 586
2005 e55 AMG
Also the odd thing always is that the boost will spike from say 16 to 17 when snapping off the throttle real quick on a hard pull. Very odd since the throttle body is before the supercharger I would think that couldn't happen.
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Joined: Jun 2017
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2005 E55
Are you using the stock intake? It's been a while since I played with this but mine did the same thing(granted at much lower boost, 12psi). I used a giant T boot and tubing to make my own intake and the boost started flat lining until red line. I think later I ended up doing the stock intake with new green filters and it held much flatter to red line as well. It's been a while since I did this testing but might be worth identifying any potential intake issues and seeing if changes there help out at all, if you don't have the air flow on the suction side to keep up at high RPMs it would explain the drop.
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Thread Starter
MBWorld Fanatic!
Joined: Jul 2014
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2005 e55 AMG
Nd-photo I have a 168 lower and 76 upper and an elaborate cooling system. Doesn't mean the blower itself isn't making too much heat but even in 45 degree ambient temps it makes no difference.
Every pull from 4,500 rpm and up to 6,300 loses 2lb's .....like clock work but If I go to say 5,500 it will only lose a little over 1 lb.
Hey drothgeb....long time man !!
I have a single 4" intake set up that flows well but I will remove the filter for the hell of it and make a pull but don't see it making any difference. But at least it's ruled out for sure.
Think I am going to step down to a 80mm upper this winter as well.
Every pull from 4,500 rpm and up to 6,300 loses 2lb's .....like clock work but If I go to say 5,500 it will only lose a little over 1 lb.
Hey drothgeb....long time man !!
I have a single 4" intake set up that flows well but I will remove the filter for the hell of it and make a pull but don't see it making any difference. But at least it's ruled out for sure.
Think I am going to step down to a 80mm upper this winter as well.
Last edited by SICAMG; Oct 14, 2022 at 03:22 PM.
Super Member
Joined: Jun 2017
Posts: 899
Likes: 140
2005 E55
Nd-photo I have a 168 lower and 76 upper and an elaborate cooling system. Doesn't mean the blower itself isn't making too much heat but even in 45 degree ambient temps it makes no difference.
Every pull to 4,500 rpm and up to 6,300 loses 2lb's .....like clock work but If I go to say 5,500 it will only lose a little over 1 lb.
Hey drothgeb....long time man !!
I have a single 4" intake set up that flows well but I will remove the filter for the hell of it and make a pull but don't see it making any difference. But at least it's ruled out for sure.
Think I am going to step down to a 80mm upper this winter as well.
Every pull to 4,500 rpm and up to 6,300 loses 2lb's .....like clock work but If I go to say 5,500 it will only lose a little over 1 lb.
Hey drothgeb....long time man !!
I have a single 4" intake set up that flows well but I will remove the filter for the hell of it and make a pull but don't see it making any difference. But at least it's ruled out for sure.
Think I am going to step down to a 80mm upper this winter as well.
The T fitment is supperrrr rought haha, lots of cutting, and fighting against the firewall. Anyways, might not be your issue but worth checking. Good luck!
