 D-Jet or L-Jet, Which is best & why? |
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| windforfun |
 Jul 23 2021, 01:36 PM
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#1
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Advanced Member  Group: Members Posts: 2,057 Joined: 17-December 07 From: Blackhawk, CA Member No.: 8,476 Region Association: None 
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Which FI system is best & why? I just watched George's video (most of it) & now I'm curious.
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| Dave_Darling |
Jul 24 2021, 12:38 AM
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#2
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914 Idiot Group: Members Posts: 15,203 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California
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They both have strong points and weaknesses.
D-jet, as mentioned, doesn't place any extra restrictions on the incoming air. It also is more tolerant of small vacuum leaks. On the downside, it is using a fairly imprecise method of working out how much air is going into the engine. It has to approximate it from using a measured pressure and the RPM. It has to make a lot of assumptions about the motor to use those to calculate the air that is going in. L-jet directly measures the volume of the air that is going in with the air-flow meter. This gives it a much more precise idea of the actual amount of air going in. That can allow for much better mixture control, and it can cope better with changes to the engine than D-jet can. The down-sides are that it places a restriction in the air flow path (the flap in the air flow meter), and that it is much less tolerant of even minor vacuum leaks than D-jet is. Pick your poison. D-jet is associated with the more powerful 914 motors (2.0s and the high-compression 1.7s), but then again most modern fuel injection systems are based on the concepts used in L-jet, and many modern FI systems are direct descendants of it. --DD |
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Posts in this topic
windforfun D-Jet or L-Jet Jul 23 2021, 01:36 PM
GregAmy So you're lookin' for a philosophical disc... Jul 23 2021, 03:04 PM JeffBowlsby Kept maintained, they both perform well and are re... Jul 23 2021, 04:40 PM 914werke :agree: Expert Testimony :trophy: Jul 23 2021, 05:23 PM ClayPerrine The D-Jet was Bosch's first commercial fuel in... Jul 23 2021, 05:23 PM wonkipop :agree: with mr. b
germans basically invented ele... Jul 23 2021, 05:26 PM
73-914
:agree: with mr. b
germans basically invented el... Jul 23 2021, 07:25 PM ClayPerrine
:agree: with mr. b
germans basically invented e... Jul 23 2021, 08:20 PM wonkipop
[quote name='73-914' post='2932871' date='Ju... Jul 23 2021, 10:17 PM JeffBowlsby Word. Clipped rom Wikipedia:
The first commercia... Jul 23 2021, 08:09 PM wonkipop
Word. Clipped rom Wikipedia:
The first commerci... Jul 23 2021, 09:06 PM MM1 Thanks for the link - great article about a specia... Jul 23 2021, 11:49 PM |
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