What's this issue with Long Tubes decreasing boost?
Thread Starter
MBWorld Fanatic!
Joined: Jan 2011
Posts: 2,159
Likes: 160
2006 E55
What's this issue with Long Tubes decreasing boost?
I understand that having less back pressure can reduce boost - but by how much are we talking? Wouldn't it almost negligible? I have been reading some threads on the board.
For instance, Long tubes on an otherwise stock exhaust, with either 172mm or 180mm pulley and a custom tune...would your boost actually decrease to less than stock boost ?
Increasing the pulley size along with long tubes can't make your lose boost...am I understanding this correctly?
Someone please school me before I decide what pulley I want to get!
Currently have EC long tubes on order!
Thanks in advance..
For instance, Long tubes on an otherwise stock exhaust, with either 172mm or 180mm pulley and a custom tune...would your boost actually decrease to less than stock boost ?
Increasing the pulley size along with long tubes can't make your lose boost...am I understanding this correctly?
Someone please school me before I decide what pulley I want to get!
Currently have EC long tubes on order!
Thanks in advance..
Super Member
Joined: Apr 2010
Posts: 781
Likes: 0
From: Bay Area, CA
E55 AMG, 72' Toyota Carina, 63' Ford F100, 72' Mercedes 250c, 15' Harley Davidson Softail
long tubes are way more efficient than the stock headers and as such, require less boost to make more power. basically the best of both world because you're getting more ummph for less strain on the engine. and it's not a HUGE amount of boost drop so you should not worry.
Thread Starter
MBWorld Fanatic!
Joined: Jan 2011
Posts: 2,159
Likes: 160
2006 E55
long tubes are way more efficient than the stock headers and as such, require less boost to make more power. basically the best of both world because you're getting more ummph for less strain on the engine. and it's not a HUGE amount of boost drop so you should not worry.
Thank you for the post. I had been leaning towards a 168, only because I'm trying to break any boost records here, but wanted to be sure I was understanding the theory in general with long tubes.
Others can please chime in with their experience as well ...
MBWorld Fanatic!
Joined: May 2011
Posts: 1,109
Likes: 20
From: Las Vegas, NV
1000Hp Diesel Trucks, 2019 E63s
The thing you need to remember when talking about boost is boost=restriction. Less boost has nothing to do with less power. If you put a bigger pulley on and lower the restriction enough you could have less boost then stock, but tons more power. In fact that'll give you a cooler more efficient engine.
MBWorld Fanatic!
Joined: Jan 2004
Posts: 7,092
Likes: 13
From: Salt Lake City (but not Morm)
2003 E55 & 2014 GL550
Thanks for that above. So true. On you tube their is a rare before and right after dyno of long tubers. Just installed and strapped down.....35 wheel gain
Trending Topics
Thread Starter
MBWorld Fanatic!
Joined: Jan 2011
Posts: 2,159
Likes: 160
2006 E55
The thing you need to remember when talking about boost is boost=restriction. Less boost has nothing to do with less power. If you put a bigger pulley on and lower the restriction enough you could have less boost then stock, but tons more power. In fact that'll give you a cooler more efficient engine.
Good info.
So when installing long tubes, would it be wise to go with a 168 or 172 pulley? I am thinking a 180 is too large and would far too much heat? I live in a state that has hot summers, but cool springs/falls and very cold winters.
Iisn't the power difference between a 172 and 180 relatively small for the amount of heat production difference?
It sounds like 168/172 is the way to go with long tubes. 180 sounds too big and you need many more cooling mods than just a HE and upgraded pump.
Correct me if I'm wrong ...
MB World Stories
The Best of Mercedes & AMG
6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)
Verdad Gallardo
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun
Verdad Gallardo
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Verdad Gallardo
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine
Verdad Gallardo
Flawlessly Restored Mercedes 190E Evo II Heads to Auction
Verdad Gallardo
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know
Verdad Gallardo
Mercedes EQS Gets A Major Update: Everything You Need to Know
Verdad Gallardo
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve
Verdad Gallardo
Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping
Verdad Gallardo
MBWorld Fanatic!
Joined: May 2011
Posts: 1,109
Likes: 20
From: Las Vegas, NV
1000Hp Diesel Trucks, 2019 E63s
I totally agree you'd want cooling upgrades if you go for a 180, but I'd suggest them to anyone. A cooler intake system is going to make for a happier engine no matter what size pulley you go with. I'm sure you'd be happy with a 168/172, either way the power will be ridiculous!
