IAT too high on dyno. Thoughts?
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W211 E55 AMG
IAT too high on dyno. Thoughts?
Dear AMG enthusiasts,
I am an '04 E55 owner from the Netherlands and have my E55 for 1,5 years now. Thanks to the US forums I gained a lot of knowledge about the Benz which helped me a lot, so thanks for that!
Before I started with smaller S/C pulleys I have done the cooling mods:
- Split cooling
- PLM bigger H/E
- Fresh 010 pump
Furthermore:
- VRP 77mm clutched S/C pulley
- RaceIQ tune
- C63 mufflers, 2nd cats removed and x-pipe
- VRP BWK
That should do the trick. But on recent dyno runs, the power and torque collapsed at higher RPMs due to the ECU pulling timing. The IATs were up to 90 degrees celcius after a few runs.
After that dyno session (477hp and 840Nm on the crank) I went back to my mechanic and the cooling system was checked and the 010 pump was replaced.
The 2nd dyno session showed the same heat problem, and 494hp and 815Nm was the outcome. The mechanic told me that I should go back to my 84mm pulley because in his opinion I reached the limit of efficiency of the S/C.
As far as I have read, the cooling mods should work in this setup. Is there something I am missing? Any cooling mods that should help me solve this?
Thanks in advance for your help, it is really appreciated.
KR, Reurda
I am an '04 E55 owner from the Netherlands and have my E55 for 1,5 years now. Thanks to the US forums I gained a lot of knowledge about the Benz which helped me a lot, so thanks for that!
Before I started with smaller S/C pulleys I have done the cooling mods:
- Split cooling
- PLM bigger H/E
- Fresh 010 pump
Furthermore:
- VRP 77mm clutched S/C pulley
- RaceIQ tune
- C63 mufflers, 2nd cats removed and x-pipe
- VRP BWK
That should do the trick. But on recent dyno runs, the power and torque collapsed at higher RPMs due to the ECU pulling timing. The IATs were up to 90 degrees celcius after a few runs.
After that dyno session (477hp and 840Nm on the crank) I went back to my mechanic and the cooling system was checked and the 010 pump was replaced.
The 2nd dyno session showed the same heat problem, and 494hp and 815Nm was the outcome. The mechanic told me that I should go back to my 84mm pulley because in his opinion I reached the limit of efficiency of the S/C.
As far as I have read, the cooling mods should work in this setup. Is there something I am missing? Any cooling mods that should help me solve this?
Thanks in advance for your help, it is really appreciated.
KR, Reurda
Last edited by Reurda; Nov 24, 2021 at 04:04 AM.
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From: Usa
mgLipGD
What was the ambient temp?
Car should be at 20* F over ambient so make sure that translate to the right * C for you. Now the high temp could be air in the system but most likely need more cooling. The car starts pulling timing at 120 F.
So imagine it’s 70 F out and the expected IAT is 90 F before you even get on it, once WOT temps will rise quickly and timing will be pulled and power lost.
The best cooling setup is not having a HE and running a Killer Chiller it Interchiller that keeps a under hood or trunk tank, and then have meth. this will keep IATs well under ambient like 30 F below and then peak about 100 F.
Car should be at 20* F over ambient so make sure that translate to the right * C for you. Now the high temp could be air in the system but most likely need more cooling. The car starts pulling timing at 120 F.
So imagine it’s 70 F out and the expected IAT is 90 F before you even get on it, once WOT temps will rise quickly and timing will be pulled and power lost.
The best cooling setup is not having a HE and running a Killer Chiller it Interchiller that keeps a under hood or trunk tank, and then have meth. this will keep IATs well under ambient like 30 F below and then peak about 100 F.
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Joined: Mar 2005
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From: America
1999 C43 AMG, 2005 E55 Wagon
I have basically the same mods except a 72mm pulley (way too aggressive, I bought it with this setup unfortunately).
Folks on Facebook said with the cooling setup you (and I) have, don't expect enough cooling if you go below an 83mm pulley. So if you're chasing power, you need more cooling. If you're chasing better temps (without respect to power) then larger pulley.
Folks on Facebook said with the cooling setup you (and I) have, don't expect enough cooling if you go below an 83mm pulley. So if you're chasing power, you need more cooling. If you're chasing better temps (without respect to power) then larger pulley.
Thread Starter
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W211 E55 AMG
What was the ambient temp?
Car should be at 20* F over ambient so make sure that translate to the right * C for you. Now the high temp could be air in the system but most likely need more cooling. The car starts pulling timing at 120 F.
So imagine it’s 70 F out and the expected IAT is 90 F before you even get on it, once WOT temps will rise quickly and timing will be pulled and power lost.
The best cooling setup is not having a HE and running a Killer Chiller it Interchiller that keeps a under hood or trunk tank, and then have meth. this will keep IATs well under ambient like 30 F below and then peak about 100 F.
Car should be at 20* F over ambient so make sure that translate to the right * C for you. Now the high temp could be air in the system but most likely need more cooling. The car starts pulling timing at 120 F.
So imagine it’s 70 F out and the expected IAT is 90 F before you even get on it, once WOT temps will rise quickly and timing will be pulled and power lost.
The best cooling setup is not having a HE and running a Killer Chiller it Interchiller that keeps a under hood or trunk tank, and then have meth. this will keep IATs well under ambient like 30 F below and then peak about 100 F.
Thread Starter
Newbie
Joined: Jun 2021
Posts: 11
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W211 E55 AMG
I have basically the same mods except a 72mm pulley (way too aggressive, I bought it with this setup unfortunately).
Folks on Facebook said with the cooling setup you (and I) have, don't expect enough cooling if you go below an 83mm pulley. So if you're chasing power, you need more cooling. If you're chasing better temps (without respect to power) then larger pulley.
Folks on Facebook said with the cooling setup you (and I) have, don't expect enough cooling if you go below an 83mm pulley. So if you're chasing power, you need more cooling. If you're chasing better temps (without respect to power) then larger pulley.
Nobody else experiences with the same setup?
Thanks!
Senior Member
Joined: Nov 2018
Posts: 335
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CLS55 AMG
You'll exceed the power you have with that set up. Hell just the 83 and headers is north of 500 wheel. I'd skip the throttlebody unless you want a world of frustration.
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MBWorld Fanatic!
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From: America
1999 C43 AMG, 2005 E55 Wagon
I am looking to replace my 72mm with an 83mm but keep the rest of my mods (bigger front intercooler, 010 pump, mid length headers, no cats) and re-tune. I should probably see the same power output due to less heat.
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Thread Starter
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W211 E55 AMG
Well, today the 77MM is swapped for the 83MM, and tomorrow we wil visit Germany 
I will be monitoring the IAT's and revert to you. Also a new dyno session is planned and then we know for sure.
At the same time I was able to score the PLM shorties from member GinDistiller which will be installed asap. Of course, after that we wil do a new dyno
I will be monitoring the IAT's and revert to you. Also a new dyno session is planned and then we know for sure.
At the same time I was able to score the PLM shorties from member GinDistiller which will be installed asap. Of course, after that we wil do a new dyno
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2006 E55
For the amount of heat a 77mm or smaller upper pulley generates, it'll be very fun for a WOT run or two, but then recovery is longer and cooling has to be more than just a HE and pump (killer chiller/trunk tank, headers to move the heat out of bay, meth etc.). On my current E55, I have an 83mm and my IATs are just perfect with an PLM XL HE and Bosch 010, even in the dead heat of summer with high humidity (you can still feel the power loss due to the heat, but these motors/cars are NOT summer cars). Unless you're chasing track records or power records, in my opinion, the 83mm is the perfect street setup without sacrificing much and suffering heatsoak left and right without spending much on cooling to keep your IATs stable and in range. Even the 80mm SCP might be too much heat.
This is my third 06 E55 and I have experience with different mods/setups and to me, for a street only car, the 83mm + tune or 83mm + headers + tune is the absolute best for a street only car and remains like stock driveability and avoiding all the heatsoak issues.
Good luck
This is my third 06 E55 and I have experience with different mods/setups and to me, for a street only car, the 83mm + tune or 83mm + headers + tune is the absolute best for a street only car and remains like stock driveability and avoiding all the heatsoak issues.
Good luck
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W211 E55 AMG
Well, during the roadtrip to Germany I have logged the IAT's. That seemed fine, the maximum I have seen was 58 degrees celcius.
However, the car had some issues which it did not have with the 77mm + tune:
- P0106 shows up sometimes, after clearing, it did not come back
- After a long and fast Autobahn drive, I get the message that comfort functions are not available
- Misfires (sometimes, mostly after a long drive)
- Stumbling engine after a long highway drive at idle
Last year the E55 was eating alternators. Two alternators went bad and later the voltage regulator died. After replacing all the parts again, the issue was sorted.
After a long highway drive (rush hour traffic) and coming to a stand still, the engine is stumbling and sometimes shuts down. Weird.
Anybody knows were to look? There are no faults in the car, maintenance is on a high level.
Thanks again,
KR, Reurda
However, the car had some issues which it did not have with the 77mm + tune:
- P0106 shows up sometimes, after clearing, it did not come back
- After a long and fast Autobahn drive, I get the message that comfort functions are not available
- Misfires (sometimes, mostly after a long drive)
- Stumbling engine after a long highway drive at idle
Last year the E55 was eating alternators. Two alternators went bad and later the voltage regulator died. After replacing all the parts again, the issue was sorted.
After a long highway drive (rush hour traffic) and coming to a stand still, the engine is stumbling and sometimes shuts down. Weird.
Anybody knows were to look? There are no faults in the car, maintenance is on a high level.
Thanks again,
KR, Reurda
Super Member
Joined: Aug 2018
Posts: 697
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From: Seattle, WA
2019 M5 Comp, 2005 Ariel Atom 2
Stock throttle body? If not that is the most likely cause of P0106, however this can also be due to a small vacuum leak elsewhere near the throttle body. Check the hard pipe going into the back of the supercharger (the one bolted to the valve cover), and the plastic brake booster plug thing, those are probably the two most common sources of leakage. A smoke test would be ideal, but sometimes it's obvious if one is loose etc.
I also had similar issues with stumbling and odd things after long highway drives in the heat of summer, eventually popped a MAP sensor code and replacing that cleared things up. They aren't too expensive (although they are a pain to get to!). I'd maybe start there if it hasn't been replaced before, if you tackle it when those headers show up you should have a little more room
.
Not sure on the comfort functions message, that sounds like an auxiliary battery issue to me but odd that it would only ping after long hard drives.
I also had similar issues with stumbling and odd things after long highway drives in the heat of summer, eventually popped a MAP sensor code and replacing that cleared things up. They aren't too expensive (although they are a pain to get to!). I'd maybe start there if it hasn't been replaced before, if you tackle it when those headers show up you should have a little more room
.Not sure on the comfort functions message, that sounds like an auxiliary battery issue to me but odd that it would only ping after long hard drives.
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From: Germany RLP
W211 E220, W211 E55, W203 C55
I'm from Germany and personally run the stock pulley shaved off to 87mm. Supercharger is a 0580 and it makes 0.7-0.8 bar. For cooling I have a bigger heat exchanger and a Pierburg CWA100 pump. My IATs don't exceed 60°C even when going 280kph. Personally I think anything under 84mm is too aggressive for German highways.
Your alternator issue sounds like a bad ground wire. It would explain, why your alternators keep dying and the engine even turns off. Maybe the ground wire for the engine /trans is bad.
Your alternator issue sounds like a bad ground wire. It would explain, why your alternators keep dying and the engine even turns off. Maybe the ground wire for the engine /trans is bad.
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W211 E55 AMG
@ GinDistiller: Yes, stock TB. I will check the vacuum hoses at the back of the SC. Regarding the MAP, I thought it has been replaced last year but I will check that. Indeed, the battery thing is weird. It only does that with the 84mm + tune. Last week I was logging data for Tony from RaceIQ to check the tune itself, and at redline the connection with the ODB dongle was also shut off. But since the alternator delivers the most output at high RPM's it cannot be the case that there is a lack of output, am I right? The alternator has also a part that wears out, forgot the name of it. Can this be the issue?
@ UncleBenz55: Thanks for the tip, we will check that also.
@ UncleBenz55: Thanks for the tip, we will check that also.
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From: Germany RLP
W211 E220, W211 E55, W203 C55
Rpm doesn't matter too for the alternator cause the regulator, charges the battery depending on necessity.
Instead of of plug and play tune, I think a dyno tune is better. It's for one safer and you'll better unfold the potential of your engine.
Instead of of plug and play tune, I think a dyno tune is better. It's for one safer and you'll better unfold the potential of your engine.
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Joined: Aug 2018
Posts: 697
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From: Seattle, WA
2019 M5 Comp, 2005 Ariel Atom 2
I agree with UncleBenz55 on looking at ground connections. You could get into the data display on the dash showing voltage and go run it up to redline, see if there are any major fluctuations, but these odd issues seem more grounding related (i.e. you have a regulator go bad and it just stays bad all the time).
Odd it seems related to the tune though. I actually prefer a good road tune if it's your daily driver, dyno tunes are great if you just track the car, but Tony does a great job after getting logs etc so you should be running great when he gets you dialed in.
MAP - if it was replaced, and you have records, check the part number and brand carefully. There have been odd issues with aftermarket MAP sensors and incorrectly sourced OEM units. It's highly unlikely and I probably sound crazy for even suggesting it, but the tune and pulley will increase boost, which is measured by the MAP, maybe if there is a problem at those higher levels it's causing some kind of electrical gremlin that isn't showing up when you are on stock levels? If you check and find it's the proper MAP though I wouldn't dive in and replace it, that code you got is much more likely to be vacuum related.
Odd it seems related to the tune though. I actually prefer a good road tune if it's your daily driver, dyno tunes are great if you just track the car, but Tony does a great job after getting logs etc so you should be running great when he gets you dialed in.
MAP - if it was replaced, and you have records, check the part number and brand carefully. There have been odd issues with aftermarket MAP sensors and incorrectly sourced OEM units. It's highly unlikely and I probably sound crazy for even suggesting it, but the tune and pulley will increase boost, which is measured by the MAP, maybe if there is a problem at those higher levels it's causing some kind of electrical gremlin that isn't showing up when you are on stock levels? If you check and find it's the proper MAP though I wouldn't dive in and replace it, that code you got is much more likely to be vacuum related.
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W211 E55 AMG
I agree with UncleBenz55 on looking at ground connections. You could get into the data display on the dash showing voltage and go run it up to redline, see if there are any major fluctuations, but these odd issues seem more grounding related (i.e. you have a regulator go bad and it just stays bad all the time
next week I have an appointment with my mechanic to discuss the MAP, vacuum and this item.
Enjoy your weekends,
KR Reurda
