Stock EFI limits, is it RPM or HP? |
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Stock EFI limits, is it RPM or HP? |
qa1142 |
Sep 5 2005, 09:42 AM
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#1
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Whiplash Group: Members Posts: 1,514 Joined: 1-June 04 From: Lake Zurich, Illinois Member No.: 2,140 |
Ok, so I am still thinking through my winter engine project. I plan to stay in "stock" class so EFI is staying. I have an L jet on my 1.8L, I have "spair" 1976 L Jet, and I have a D jet that came with my 2.0L project motor.
2.0L give longer stroke and more torque (right) while staying 1.8L would give faster revs and (more rpm??) So what is CFM / RPM / power limits of each injection system. Seams like L jet with air flow sensor would keep mix better at all RPM. Is that true? Would I run out of CFM if I bolt it to a 2.0L? I am thinking, RAT EFI cam to match D or L jet, Mallory if L jet, 2.0L heads reworked by Len that match, then either 1.8 or 2.0 basically stock Piston / cyl kit from Jake also. Let me hear your "un-biased" (IMG:http://www.914world.com/bbs2/html/emoticons/slap.gif) inputs, I need to start ordering parts soon. (IMG:http://www.914world.com/bbs2/html/emoticons/mueba.gif) |
Mueller |
Sep 5 2005, 10:08 AM
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914 Freak! Group: Members Posts: 17,146 Joined: 4-January 03 From: Antioch, CA Member No.: 87 Region Association: None |
well, "stock" is "stock", so the mods you are talking about is not allowed more than likely and would be "cheating" (IMG:http://www.914world.com/bbs2/html/emoticons/smile.gif) with the L-Jet, I've run it on a higher compression 2.0 motor with a header, ran great, but I never checked the O2 levels or dyno'd it.....I do know the car ran great as does a few other people that rode in it... with the L-jet, once you reach a certain RPM, the flapper is pretty much wide open and the ECU then just adds fuel based on RPM....it does work, but at what RPM or HP level will it lean out at?? I'm sure you could monitor the O2 level and compensate for it if you understand the fuel injection thru and thru...the easiest method would be to tie into the CHT circuit and "fake" it out so that it adds more fuel at the RPM threshold due to it thinking the both the D-Jet and L-Jet are going to be limited somewhat....since more people have tweaked the D-jet, you are safer going that route unless you want to learn how to optimize the L-Jet...personally if I "had" to stick with one of the factory FI's, I'd go with L-jet since that is what I was more comfortable working with. Oh yea, you can run a Mallory with D-jet, I've done it. The mechanical trigger points are replaced with an optical trigger circuit. Do a search for "mallory" and "circuit" using my name. Pretty easy, cost about $10 or so I think |
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