View Full Version : FAST EZ EFI with 7" of vacuum at idle
Stale67SS
05-15-2010, 03:22 PM
See that FAST recommends 8" of vacuum at idle for this system.
Anyone got experience with this system with less idle vacuum?
I have a 383 sbc with a magnum cam producing 7" of vacuum at 850 rpm.
From what i have read there is some who says it will work.
Want to buy such a system but, need to be sure before i order.
ccracin
05-15-2010, 05:16 PM
Call the FAST tech line. They are good guys and will help you out.
Vegas69
05-15-2010, 05:52 PM
Turn your idle up to 1000.
Stale67SS
05-16-2010, 04:28 AM
1. Talked to a guy at FAST which said it had to be at least 8". Seemd like a "political" answer.
2.Read an article with a FAST engineer who said that you could run down to 7" but had to start with a bit higher idle speed when thuning the system and then gradually take the idle down.
= Confused.
So if anyone has hands on experience it is appreciated.
Josh69
05-25-2010, 12:09 PM
I don't have an practical experience, but I will say that I called FAST and asked them the same thing when my old motor only had 6-7" of vacuum. I was told that it would work. So maybe some guys are more stringent than others. I was led to believe the 8" wasn't a hard and fast rule, but more of a 'recommendation'. Sorry, I can't be any more help. But I did put in a milder cam this go-round so when I go EFI it's not an issue.
You could contact Holley about their Avenger EFI, seems pretty similar, and may not have that requirement.
Vegas69
05-25-2010, 12:11 PM
More initial timing will also increase your vaccum.
64duece
05-26-2010, 05:30 AM
Another option with the Holley is having timing control which will help with idle quality as well. There are no "vacuum limits" with the Holley systems as they can be tuned to run a hybrid of Alpha-N to Speed Density.
The Avenger EFI which uses the handheld controller does have some tuning limitations built in "on purpose" which doesn't access those types of tunes through normal mapping. In such a cases....just break out the laptop and go through the standard software.
hemikiller
07-17-2010, 01:15 AM
See that FAST recommends 8" of vacuum at idle for this system.
Anyone got experience with this system with less idle vacuum?
I have a 383 sbc with a magnum cam producing 7" of vacuum at 850 rpm.
From what i have read there is some who says it will work.
Want to buy such a system but, need to be sure before i order.
Rich Nedbal is a fast dealer and can tune your car over the internet!!! I use FAST SMPI with traction control on my 528 solid roller hemi that runs on e-85 and rich tammed my hemi after we fixed my mistakes in a few hours.
call him 209-247-6497 you won't be sorry!!!!
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