Notices
Drivetrain Gearbox, Diffs & Driveshafts etc

Bigger / more MAF sensors

Old Aug 19, 2002 | 02:43 PM
  #1  
Pavlo's Avatar
Pavlo
Thread Starter
Scooby Regular
 
Joined: May 2002
Posts: 6,316
Likes: 2
From: home
Post

As per Andy Fs discussion, thought it better here.
Andy,

This goes back to Johns musings on the subject a while ago. The problem is the MAFs are non linear, so you can't simply add voltages. What you could do is add some controller that linearised their output, summed it, and spat it out as a linear signal. The calibrate the MAFs in the ECU with a linear signal rather than the curve currently used.

The above is based on the assumption that the MAFs could have significantly different flow through them that the voltages couldn't be accurately summed, which is probably the case.

I am no microcontroller guru, but I think it should be quite easy as we know the curve for the MAF sensor, even if I don't know the units, doesn't really matter provided the proportions are correct.

I assume the 2 turbos will feed a common plenumn? If not, probably best to use 2 ecus and feed 8 injectors



[Edited by Pavlo - 8/19/2002 2:44:10 PM]
Reply
Old Aug 19, 2002 | 03:26 PM
  #2  
Andy.F's Avatar
Andy.F
Subaru Tuning Specialist
 
Joined: Jun 2002
Posts: 6,654
Likes: 1
From: 7.74 @179 mph 1/4 mile - road legal
Post

I have considered using twin turbo's with 2 OEM MAF's, 2 OEM ECU's and 8 std injectors, one ECU supplying the ignition map which would need completely re-done due to its MAF measuring only 50% of the air flow.
You could switch between ECU's for timing maps, one for pump fuel, one for race fuel Synchronising the wastegates on the turbo's would be very important to balance the flow between the MAF's

All you would need is some gash secondhand OEM bits, no fancy ECU's, big Injectors or hybrid turbo's
Of course a pair of decent re-maps would be the key
Reply
Old Aug 19, 2002 | 04:01 PM
  #3  
Pavlo's Avatar
Pavlo
Thread Starter
Scooby Regular
 
Joined: May 2002
Posts: 6,316
Likes: 2
From: home
Post

i was considering just a bigger MAF sensor, as the standard unit it pretty small. Anyone know of any alternatives that they can get the flow info for?

paul
Reply
Old Aug 19, 2002 | 04:19 PM
  #4  
Pavlo's Avatar
Pavlo
Thread Starter
Scooby Regular
 
Joined: May 2002
Posts: 6,316
Likes: 2
From: home
Post

hmm, these people seem to have some interesting products, how about a 200mm diameter MAF sensor?!?!

http://www.pro-flow.com/

They sell each sensor with a calibration sheet.

Paul
Reply
Old Aug 19, 2002 | 05:21 PM
  #5  
Andy.F's Avatar
Andy.F
Subaru Tuning Specialist
 
Joined: Jun 2002
Posts: 6,654
Likes: 1
From: 7.74 @179 mph 1/4 mile - road legal
Thumbs up

Mmm, nice, the 80 pro model should do ok with an 800 bhp limit
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
SilverM3
ScoobyNet General
8
Feb 24, 2021 01:03 PM
Mattybr5@MB Developments
Full Cars Breaking For Spares
28
Dec 28, 2015 11:07 PM
Mattybr5@MB Developments
Full Cars Breaking For Spares
12
Nov 18, 2015 07:03 AM
Ganz1983
Subaru
5
Oct 2, 2015 09:22 AM
thunder8
General Technical
0
Oct 1, 2015 09:13 PM


Thread Tools
Search this Thread

All times are GMT +1. The time now is 08:24 PM.