What is the difference between a, 74 L-Jet and a 75 L-Jet |
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What is the difference between a, 74 L-Jet and a 75 L-Jet |
jsayre914 |
Apr 29 2009, 10:20 AM
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#1
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Speed Up !!! Group: Members Posts: 3,199 Joined: 10-February 08 From: Timonium MD 21093 Member No.: 8,696 Region Association: MidAtlantic Region |
I was told the 74 and 75 L-jet for a 1.8 motor is different. I was wondering what exactly were the differences, and can you see them just at a glance. If anybody would like to post a picture please do... (IMG:style_emoticons/default/popcorn[1].gif)
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brant |
Apr 29 2009, 10:32 AM
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#2
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914 Wizard Group: Members Posts: 11,739 Joined: 30-December 02 From: Colorado Member No.: 47 Region Association: Rocky Mountains |
I think you mean 1974 vs 1975
no L-jet in 73 Djet was the fuel injection in 1973.. a lot of differences |
davesprinkle |
Apr 29 2009, 10:32 AM
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#3
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Senior Member Group: Members Posts: 720 Joined: 13-October 04 From: Berkeley, CA Member No.: 2,943 Region Association: None |
I was told the 73 and 75 L-jet for a 1.8 motor is different. I was wondering what exactly were the differences, and can you see them just at a glance. If anybody would like to post a picture please do... (IMG:style_emoticons/default/popcorn[1].gif) '75 and '76 L-jets were different from the earlier years. The major difference was the additional pin on the airflow meter -- early meters had 6 pins and later meters had 7 pins. Of course, the changes aren't limited to the meter -- the wiring harness and the ECU were both changed to support the different meter. So you can't just swap out 1 component; you've got to do all 3 for a backdate or update. I've run my '74 engine with a -76 L-jet system. Just had to swap out the meter, wiring harness, and ECU. |
zonedoubt |
Apr 29 2009, 10:34 AM
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#4
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Canadian Member Group: Members Posts: 668 Joined: 14-May 03 From: Vancouver, BC Member No.: 696 Region Association: Canada |
I was told the 73 and 75 L-jet for a 1.8 motor is different. I was wondering what exactly were the differences, and can you see them just at a glance. If anybody would like to post a picture please do... (IMG:style_emoticons/default/popcorn[1].gif) L-jet is on '74 and '75 1.8L only. http://www.pelicanparts.com/914/How_to_buy_a_914.htm |
ArtechnikA |
Apr 29 2009, 10:54 AM
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#5
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rich herzog Group: Members Posts: 7,390 Joined: 4-April 03 From: Salted Roads, PA Member No.: 513 Region Association: None |
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jsayre914 |
Apr 29 2009, 11:52 AM
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#6
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Speed Up !!! Group: Members Posts: 3,199 Joined: 10-February 08 From: Timonium MD 21093 Member No.: 8,696 Region Association: MidAtlantic Region |
I think you mean 1974 vs 1975 no L-jet in 73 Djet was the fuel injection in 1973.. a lot of differences edited. (IMG:style_emoticons/default/rolleyes.gif) so i need to pull a wire from the airflow and count the pins, that is the only way to tell? |
davesprinkle |
Apr 29 2009, 01:44 PM
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#7
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Senior Member Group: Members Posts: 720 Joined: 13-October 04 From: Berkeley, CA Member No.: 2,943 Region Association: None |
I think you mean 1974 vs 1975 no L-jet in 73 Djet was the fuel injection in 1973.. a lot of differences edited. (IMG:style_emoticons/default/rolleyes.gif) so i need to pull a wire from the airflow and count the pins, that is the only way to tell? That's probably the easiest way. Or you could look at the PN on the ECU. Sorry, don't have the numbers handy, but you can search the forum for them. |
orange914 |
Apr 29 2009, 10:31 PM
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#8
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http://5starmediaworks.com/index.html Group: Members Posts: 3,371 Joined: 26-March 05 From: Ceres, California Member No.: 3,818 Region Association: Northern California |
L-jet is on '74 and '75 1.8L only. ...and '76 912E 2,0 ... true it's not a 914 but it's hard to look at any T-IV engine or injection component in isolation and be able to tell exactly where it belongs. i had a 76 2.0 bus w/ L Jet... if that helps |
r_towle |
Apr 30 2009, 05:47 AM
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#9
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Custom Member Group: Members Posts: 24,624 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
I would suspect the ECU and the AFM are designed in pairs..probably the wiring harness also.
Look at the top of this page...914info...other 914 related sites. The Ljet bible site is in there as a link. Should be easy enough to get part numbers...the AFM looks different just at a glance, but you would need to see both together first to get the idea. Rich |
ClayPerrine |
May 1 2009, 06:48 AM
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#10
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Life's been good to me so far..... Group: Admin Posts: 15,820 Joined: 11-September 03 From: Hurst, TX. Member No.: 1,143 Region Association: NineFourteenerVille |
The pin numbers on the air flow meter are the key. 7 pins is a 75. 6 pins is a 74. The wiring harness and ecu are definitely different. If you put a 75 ECU on a 74, you will get rich running.
The difference in the AFM is that in 74 the air temp sensor in it used a common wire with the meter part. In 75 they made them separate. All of the other parts on the L-Jet will interchange between 74 and 75, but the harness, AFM and ECU have to be from the same year. And don't even think about using the L-Jet from a 912E. It has different locations for the plugs for the power and ECU, and it only uses one contact in the throttle switch circuit. |
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