Fuel injection to Carbs? |
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Fuel injection to Carbs? |
torakki |
Jun 27 2024, 11:32 AM
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#1
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Member Group: Members Posts: 51 Joined: 5-October 18 From: Nor Cal Member No.: 22,545 Region Association: Northern California |
In the process of swapping the FI, on my 2.0L to Empi carbs. My research never found anything about the dizzy needing to be changed. Now I see in the Empi instructions, to swap the distributor. It sounds like, just for timing advance. I wasn't planning on the extra expense so is this necessary?
Thanks |
emerygt350 |
Jun 27 2024, 05:38 PM
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#2
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Advanced Member Group: Members Posts: 2,403 Joined: 20-July 21 From: Upstate, NY Member No.: 25,740 Region Association: North East States |
Why is the advance and retard even a part of this? Retard works at closed throttle and ported advance works at a feather throttle (and yes, they play against each other in cool ways) but they only do that. Not sure what kind of performance 'gain' is being imagined here. Retard gives you a nice idle when you have a bunch of advance dialed in, advance burns better at cruise. Before, what, 73?, it was advance only? Then it was both for a year and a bit, then just retard. Carbs have ported and manifold vacuum, you should be able to continue with both if your dizzy actually has them. Dipping into the throttle, maybe you might get a hair of a feel but jamming it to wot, there is no time for ported vacuum to do anything for you. Now when you jam it off closed throttle with retard doing its thing, certainly you get an extra immediate 10 degrees advance but it just brings you to what you would have without it.
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Superhawk996 |
Jun 27 2024, 06:13 PM
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#3
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914 Guru Group: Members Posts: 6,469 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
Why is the advance and retard even a part of this? Because vacuum canisters are designed to work between specified vacuum levels. When you go from a situation where vacuum source was designed to be taken off a common plenum / throttle body and then is switched to carb, often with a single cylinder vacuum source, the distributor behavior changes. The result often being that you don’t get enough advance during transient part throttle conditions. This ends up being mistaken for and feeling like a carburetor problem which it isn’t. Don’t disagree with you about wide open throttle behavior being unchanged when vacuum signal is very low and centrifugal advance dominates as RPMs climb. However, most people aren’t driving WOT for any significant percentage of a drive cycle. |
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