Question regarding boost readings through Torque app
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2018 E63S AMG, 2003 SLK 230 Sport, 2004 SL 600, 2006 SLK 55 AMG, 1998 E320 Wagon
Question regarding boost readings through Torque app
So all this talk of AFRs and engines blowing up is a frightening thing to say the least, so I did some research and used my Torque app to check on the boost pressure.
Now I've got a boost pulley on and Kleemann headers. When I'm on WOT, the boost pressure has gone no higher than 12 pounds. I was under the impression that stock was 11.8 and the pulley brough it up to 13 or so.
Is there something I'm missing there? If the numbers are true, couldn't I theoretically stack a 168 or even a 175 safely without worrying about running too lean? I was under the impression that anything over 15 pounds is a bad idea on stock injectors/rail.
Now the whole fuel filter/tank this is a different story. My tank is fine, don't get me wrong. Absolutely no problems with it. Seeing that one tank though with the completely black filter worried me too, and it's apparently no easy task just to replace the filter. Looks like you have to replace the whole unit or even the tank.
So are the readings right or are they lower than what they should be?
Now I've got a boost pulley on and Kleemann headers. When I'm on WOT, the boost pressure has gone no higher than 12 pounds. I was under the impression that stock was 11.8 and the pulley brough it up to 13 or so.
Is there something I'm missing there? If the numbers are true, couldn't I theoretically stack a 168 or even a 175 safely without worrying about running too lean? I was under the impression that anything over 15 pounds is a bad idea on stock injectors/rail.
Now the whole fuel filter/tank this is a different story. My tank is fine, don't get me wrong. Absolutely no problems with it. Seeing that one tank though with the completely black filter worried me too, and it's apparently no easy task just to replace the filter. Looks like you have to replace the whole unit or even the tank.
So are the readings right or are they lower than what they should be?
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Joined: Nov 2006
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From: NJ/Greece
2006 CLS55 & 2002 SL55 (R129) Silver Arrow
I think their right, I had the same boost numbers with that setup.
Basically your headers (and the deletion of your primary cats) help lower your boost while the pulley brings it back up.
Basically your headers (and the deletion of your primary cats) help lower your boost while the pulley brings it back up.
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2006 E55
Where are you getting that stock boost is 11.8? That is oddly high and maybe for a car at sea level. In any event, most cars are running low 10s to low 11s for stock boost.
What is the altitude of where you are in California? That has an impact.
FWIW, I use the Torque app as well ... when I was stock, I was seeing a max of ~10.2 - 10.5 and I'm roughly 24m above sea level. I put 408/482 when I was bone stock.
With the addition of the smaller upper pulley, I am seeing about 1psi more, with peak being roughly 11.4-11.5.
Aftermarket headers and no primaries will result in boost loss although you gain a substantial amount of power... so those numbers are likely correct given those factors.
IMHO, don't run too much boost. I think 10-11psi is the perfect spot for this car. Headers and TB are key, but I'm done with power adders...already not enough room to open her up for more than a gear or two
What is the altitude of where you are in California? That has an impact.
FWIW, I use the Torque app as well ... when I was stock, I was seeing a max of ~10.2 - 10.5 and I'm roughly 24m above sea level. I put 408/482 when I was bone stock.
With the addition of the smaller upper pulley, I am seeing about 1psi more, with peak being roughly 11.4-11.5.
Aftermarket headers and no primaries will result in boost loss although you gain a substantial amount of power... so those numbers are likely correct given those factors.
IMHO, don't run too much boost. I think 10-11psi is the perfect spot for this car. Headers and TB are key, but I'm done with power adders...already not enough room to open her up for more than a gear or two
Last edited by ArmoE55; Oct 22, 2013 at 09:14 PM.
Thread Starter
MBWorld Fanatic!
Joined: Jul 2004
Posts: 1,276
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From: California
2018 E63S AMG, 2003 SLK 230 Sport, 2004 SL 600, 2006 SLK 55 AMG, 1998 E320 Wagon
Where are you getting that stock boost is 11.8? That is oddly high and maybe for a car at sea level. In any event, most cars are running low 10s to low 11s for stock boost.
What is the altitude of where you are in California? That has an impact.
FWIW, I use the Torque app as well ... when I was stock, I was seeing a max of ~10.2 - 10.5 and I'm roughly 24m above sea level. I put 408/482 when I was bone stock.
With the addition of the smaller upper pulley, I am seeing about 1psi more, with peak being roughly 11.4-11.5.
Aftermarket headers and no primaries will result in boost loss although you gain a substantial amount of power... so those numbers are likely correct given those factors.
IMHO, don't run too much boost. I think 10-11psi is the perfect spot for this car. Headers and TB are key, but I'm done with power adders...already not enough room to open her up for more than a gear or two
What is the altitude of where you are in California? That has an impact.
FWIW, I use the Torque app as well ... when I was stock, I was seeing a max of ~10.2 - 10.5 and I'm roughly 24m above sea level. I put 408/482 when I was bone stock.
With the addition of the smaller upper pulley, I am seeing about 1psi more, with peak being roughly 11.4-11.5.
Aftermarket headers and no primaries will result in boost loss although you gain a substantial amount of power... so those numbers are likely correct given those factors.
IMHO, don't run too much boost. I think 10-11psi is the perfect spot for this car. Headers and TB are key, but I'm done with power adders...already not enough room to open her up for more than a gear or two
Either way, the most I'm going to go is stacking a 175 with the boost pulley. I've considered a Kleemann 168 for safety sake, but it *is* a difference of 1.1 pounds. Given, I don't know entirely if 1 more pound would make that much of a difference. Being safe than sorry is a big thing for me.
I saw on EC's website that normal stock boost for the 55 is 11.8. I'm guessing that's not quite right then...?
Thread Starter
MBWorld Fanatic!
Joined: Jul 2004
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From: California
2018 E63S AMG, 2003 SLK 230 Sport, 2004 SL 600, 2006 SLK 55 AMG, 1998 E320 Wagon
MBWorld Fanatic!
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2006 E55
Trust me, 11.8 is NOT the norm for stock boost on these cars. More like 10s is the majority. Honestly, if you're going to go with a larger pulley, the 168 is perfect. I've driven a car with a 168 and tune and it feels almost exactly the same as my car with its mods. I have the upper smaller pulley and don't feel the car needs anymore boost. Plenty of ways to get 'clean' power out of these cars without upping the boost (e.g. headers, TB etc.). Sure, you lose boost but the gains are substantial.
