Home  |  Forums  |  914 Info  |  Blogs
 
914World.com - The fastest growing online 914 community!
 
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG. This site is not affiliated with Porsche in any way.
Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners.
 

Welcome Guest ( Log In | Register )

> tuning d-jet 2.0('75) - A/F ratio, effects on engine temp, Am i running lean on highway?- 14.0 @ 65-70 mph
DRPHIL914
post Jul 16 2014, 06:51 AM
Post #1


Dr. Phil
*****

Group: Members
Posts: 5,768
Joined: 9-December 09
From: Bluffton, SC
Member No.: 11,106
Region Association: South East States



So i've been able to observe my A/F ratio for the past 2 weeks, driving the car daily to work and some short trips of 30-75 miles.

yesterday evening, with the outside temp being @ 90, i noticed that as i increased my speed from @ 60mph i was running about 190 temp, A/F was @ 12.5-13.2 or so. but as i increased my speed to closer to 70, temp rose to 210 or so, maybe a bit more, and the A/F went up to @14.2 . As i slowed down, and even at idle ,the temp came down to @ 180-190 again.

- so is it because of running more lean? could it be timing/advance effecting this ? or do i need to adjust the MPS?

cold idle it runs at 10.5-11, warms up and driving around town im around 12.5, hard acceleration in leans out some around 13.5, etc .

- its at Bob Woodmans today, getting valves set/checked and timing(lost my timing mark on the impeller) so that will all be sorted out. today and taken out of the equation.

oh, and the thermostat works, fins are in the right position , no blockage etc.
- running brad penn oil.
-
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
 
Reply to this topicStart new topic
Replies
worn
post Jul 16 2014, 10:17 AM
Post #2


can't remember
****

Group: Members
Posts: 3,162
Joined: 3-June 11
From: Madison, WI
Member No.: 13,152
Region Association: Upper MidWest



QUOTE(Philip W. @ Jul 16 2014, 04:51 AM) *

So i've been able to observe my A/F ratio for the past 2 weeks, driving the car daily to work and some short trips of 30-75 miles.

yesterday evening, with the outside temp being @ 90, i noticed that as i increased my speed from @ 60mph i was running about 190 temp, A/F was @ 12.5-13.2 or so. but as i increased my speed to closer to 70, temp rose to 210 or so, maybe a bit more, and the A/F went up to @14.2 . As i slowed down, and even at idle ,the temp came down to @ 180-190 again.

- so is it because of running more lean? could it be timing/advance effecting this ? or do i need to adjust the MPS?

cold idle it runs at 10.5-11, warms up and driving around town im around 12.5, hard acceleration in leans out some around 13.5, etc .

- its at Bob Woodmans today, getting valves set/checked and timing(lost my timing mark on the impeller) so that will all be sorted out. today and taken out of the equation.

oh, and the thermostat works, fins are in the right position , no blockage etc.
- running brad penn oil.
-

Are you running an unmolested stock MPS? It seems similar to what I have seen, and how I find the engine wants to run. It should be richer than 14 when you are heading up a hill though.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
DRPHIL914
post Jul 16 2014, 11:02 AM
Post #3


Dr. Phil
*****

Group: Members
Posts: 5,768
Joined: 9-December 09
From: Bluffton, SC
Member No.: 11,106
Region Association: South East States



QUOTE(worn @ Jul 16 2014, 12:17 PM) *

QUOTE(Philip W. @ Jul 16 2014, 04:51 AM) *

So i've been able to observe my A/F ratio for the past 2 weeks, driving the car daily to work and some short trips of 30-75 miles.

yesterday evening, with the outside temp being @ 90, i noticed that as i increased my speed from @ 60mph i was running about 190 temp, A/F was @ 12.5-13.2 or so. but as i increased my speed to closer to 70, temp rose to 210 or so, maybe a bit more, and the A/F went up to @14.2 . As i slowed down, and even at idle ,the temp came down to @ 180-190 again.

- so is it because of running more lean? could it be timing/advance effecting this ? or do i need to adjust the MPS?

cold idle it runs at 10.5-11, warms up and driving around town im around 12.5, hard acceleration in leans out some around 13.5, etc .

- its at Bob Woodmans today, getting valves set/checked and timing(lost my timing mark on the impeller) so that will all be sorted out. today and taken out of the equation.

oh, and the thermostat works, fins are in the right position , no blockage etc.
- running brad penn oil.
-

Are you running an unmolested stock MPS? It seems similar to what I have seen, and how I find the engine wants to run. It should be richer than 14 when you are heading up a hill though.


I have 2 non leaking MPS's. the one i am runnint was resealed and set to factory specs by Scott in NH(who''s son just bought the 944). he has a wavetech and callibrated it. after installing it, i was having severe hunting, and it was definitely too lean, so ive been gradually tweeking it but before the A/F meter was installed, so it was more by feel and engine response. i increased richness across the board until it quit hunting and would idle decently(consider all thoer things are taken care of- no vac leaks, timing set, etc etc) so it really is running pretty good now, when warm it idles at @ 950 with lights on , maybe 1000 without, very smooth. i was going to take a peak at the plugs too again just to look at color etc.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post

Posts in this topic


Reply to this topicStart new topic
1 User(s) are reading this topic (1 Guests and 0 Anonymous Users)
0 Members:

 



- Lo-Fi Version Time is now: 7th June 2024 - 07:54 PM