Feb 27, 2007
1,261
0
Behind Wilko
thanks to Nick we have found the problem with the low reading MAF and as two very clever people have said, its because of the MAF housing. We are still confused as to how it managed to run good figures on that housing before but who cares now :)

as far as the ID goes, Nicks housing (a Bosch unit) is the same as the end i still have off my old MAF. i dont know why but our housings are 80mm OD and 72.2mm ID where the sensor sits. if anyone knows more about this i would appreciate their input.... its all a bit strange!

So today Nick kindly let me swap parts from car to car and we ran logs on both cars in all combinations (my maf sensor in Nicks housing etc etc), we found that the problem transfered onto Nicks car and my car pulled good figures with Nicks housing on... the log is below

Still on T7 B7 and NOT running wmi

Code:
Sunday	15	March	2009	10:18:21						
1ML 906 032 A  		1.8l R4/5VT      01 0001								

	Group A:	'003				Group B:	'020			
		RPM	Mass Flow	Load	Ign. Timing		Idle Stabilization	Idle Stabilization	Idle Stabilization	Idle Stabilization
	TIME					TIME				
MARKER	STAMP	 /min	 g/s	%	 °BTDC	STAMP	 CF	 CF	 CF	 CF
	17.51	2520	20.14	12.5	36	17.09	0	0	0	0
	18.31	2560	20.42	12.9	34.5	17.89	0	0	0	0
	19.13	2600	19.06	12.2	36	18.71	0	0	0	0
	19.93	2600	19.25	12.5	36	19.51	0	0	0	0
	20.73	2720	60.22	79.6	26.3	20.31	0	0	0	0
	21.53	3080	115.31	100	12.8	21.13	0	0	0	0
	22.34	3600	137.97	100	9	21.94	0	0	0	0
	23.14	4160	169.97	100	10.5	22.74	0	0	0	0
	23.94	4680	185.75	100	9.8	23.54	0	0	0	0
	24.76	5200	201.06	100	9.8	24.34	0	0	0	0
	25.56	5600	209.56	100	11.3	25.16	0	0	0	0
	26.36	6040	215.31	100	12	25.96	0	0	0	0
	27.16	6400	216.69	99.6	13.5	26.76	0	0	0	0
	27.97	6720	219.11	100	16.5	27.57	0	0	0	0
	28.77	5360	142.33	81.6	26.3	28.39	0	0	0	0


all i need to do now is to make a sleeve for my MAF housing (i really want to keep it) but i dont know how thick....as i cant put material back on i am going to start thick (2mm wall), then run a log and if the values are too high, bore some more out.. i suppose the only thing that will happen if they are slightly high is it will want to run richer.

Well done and thanks to Dave and John :thumbup:, if we hadnt got mixed up in this 72.2mm ID business this would have been closed a while ago. at least we are there now.

once i have the Sleeve made to the right thickness i will start again on the WMI and timing malarky..
 
Last edited:

mrwookie

Big Daddy...
Mar 22, 2008
716
0
Cambs & Herts
Well done fellas and bet your glad you finally have it all figured now.
Oh and by the way that little calculation i said about, the one you didn't like too much ;), if you 219g/s x 1.3 = 284.7bhp pretty close me reckons..........:whistle:;)
 
Feb 27, 2007
1,261
0
Behind Wilko
Well done fellas and bet your glad you finally have it all figured now.
Oh and by the way that little calculation i said about, the one you didn't like too much ;), if you 219g/s x 1.3 = 284.7bhp pretty close me reckons..........:whistle:;)

LOL!!! thanks for that ED :) i still dont like it :p

aaron what coilovers do you have mate?

KW Variant 2s Ben... they get top marks form myself and Nick
 

mrwookie

Big Daddy...
Mar 22, 2008
716
0
Cambs & Herts
Yea sorry about that just made me chuckle... :)
Did the car feel any different with nick's MAF on Aaron? Just quite a difference in the g/s readings!
 
Feb 27, 2007
1,261
0
Behind Wilko
:) no i didnt feel any difference but i know it was flowing around 220g/s before it just didnt know it..

i think the gains will come if i can push the timing again.
 
Feb 27, 2007
1,261
0
Behind Wilko
Thanks Dave, hopefully i can get down to some proper work now :funk::funk:

i didnt get the bosch number from Nicks MAF but im assuming its this one - 0 280 218 065
from the TT Tweakers guide link i posted. im sure Nick will correct me if im wrong
 

Skorchio

600 Miles to a tank :)
Jan 23, 2007
1,570
1
Nr Milton Keynes
Hmmmm lol.. Ill have a butchers when i get in to night :) I also need to stick a cable tie on my boost gauge as well. Hope that stops the hissing!!
 
Feb 27, 2007
1,261
0
Behind Wilko
You will need a inline restrictor to stop it buzzing/hissing mate, like this clicky.



Nick has a audible leak on his gauge....it just about gets to 20psi and actual boost is fairly consistently 50mbar down on requested. not much but a leak all the same... im assuming the inline restrictor wont solve that will it? (mine has a sensor in the engine bay so i havent got any experience with these sort of problems)
 

Skorchio

600 Miles to a tank :)
Jan 23, 2007
1,570
1
Nr Milton Keynes
Ill try a cable tie first if not ill have a go at that. Was fine before remap, and i should be boosting over 20psi.. so im guessing its leaking boost at the back..
 
Feb 27, 2007
1,261
0
Behind Wilko
sleeve has been made and fitted, i also had the air straightener put back in.... lets hope it works, ill run some logs on the way home...:hide:
 
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