BMW 1 Series Coupe Forum / 1 Series Convertible Forum (1M / tii / 135i / 128i / Coupe / Cabrio / Hatchback) (BMW E82 E88 128i 130i 135i)


Post Reply
Thread Tools Search this Thread
      10-17-2011, 10:05 AM   #1
Private First Class

Drives: 2008 135i, 1991 911 Turbo
Join Date: Apr 2008
Location: Dallas, TX

iTrader: (0)

Observations on air temp

Pulled the below quote from a post back in 2010 as I was searching for information on air intake temps on the 135i. I've been seeing roughly a 20 degree delta between ambient and charge air intake temps while cruising on the freeway (ie. 65 ambient / 83 degree charge air temp). This appears to be the norm for these cars, but I'm surprised BMW didn't do more to improve cold air intake given it's role in making more horsepower.

I also own a '91 911 Turbo with a standalone EMS and was doing some comparisons over the past week. Under the same conditions, I'm seeing a ~5 degree variance in the Porsche (with, what I'd call a disadvantaged engine poisition for air cooling, not to mention the intercooler literally sitting on top of the motor) versus a ~20 degree variance in the BMW. The only reason I can see BMW going the route they went is for improved spool - short intake tract, smaller intercooler with little pressure drop. Makes sense, I guess.

Has anyone looked into improving intake air temps with the OEM intercooler?


Originally Posted by Ilma View Post are not the first to do this mod.

I used a coat hanger....ghetto I know!

In regards to air temps.

I have been logging intake temps in 72F weather and find that at constant cruise low throttle around 2-3K rpm my intake temps sit around 89 to 90F.

During WOT my temps drop as low as 86 during a full 3rd gear pull from 3K rpm.

Not bad for a DCI setup.

Even with a cold air intake setup, your ambient air is going to pick up some heat travelling past the turbos.

I had the stock CAI on last week and noted about a 5 degree improvement over the DCI's at times, but the DCI's are less restrictive and have better throttle response.

They also pull a little harder at higher rpms which is where to stock CAI restriction becomes more of an issue.

A CAI might be better at heatsoak recovery though, since you would be pulling in cooler air immediately to help bring the intercooler temp back down.

But I found that I could get my intercooler back down from 106F to 89F just by using half throttle or so for a couple of gears.

The key is to get airflow into the intercooler.

This is with an aftermarket intercooler though.
Appreciate 0
Post Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

All times are GMT -4. The time now is 03:35 AM.

Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.,,,,,,,,, logo and trademark are properties of BIMMERPOST