EFI Intakes What the H----

[oldracing2]

Ran an EFI intake Saturday night and all we could do was just make laps. It would stumble and stutter if you tried to put your foot in it , feathering helped a little. Running the layered stlye intake with JVB 1" spacer. Checked for everything one would look for, everything good. So any help or feed back would be appreciated.

[car62]

as ive stated MANY times...they are JUNK no matter what you do to them....my advice would be to use it as a door stop.

[toml]

Make sure your gasket is sealing between the spacer and carb . I had this problem with using the Motor Craft 121 Carb . Hope this helps Toml

[Milford Motorsports]

On the 2150 motorcraft carb the power valve cover extends lower than the base of the carb.You will have to use the special 1/8 or 1/4 in.base gasket made for that carb.I have never had any problems with the EFI intakes as far as performance,only the carb mounting problem.

[oldracing2]

I am running the Holly 7448 carb

[longhornracer]

Im with Car62. I have tried it with Jbv adapter and had horrible luck with it. The only time I have seen it work better than the stock intake is one that was port matched to the head.

[racerman]

We have run the EFI with a 7448 and they run better IMO than an oval port intake. No where near junk if everything else is good.

[Brad]

I have very good results with and efi manifold. We use the 2" spacer and and manifold ported by JBV.
Our racing is on 1/4 to 1/2 mile asphalt normanlly with high banks. Did a lot of dyno work on a 2340 non rooler with 350 Holley. We do not use a large range of rpm since it is asphalt. We modified the manifold to an open plemum removing as much material from inside the manifold as we could and removing the divider from the adpter. The power and egt balance compared to the "E" manifold was over 20.
Brad

[jatchis]

The symptoms you're describing sound like pullover to me, especially given the 7448.

When you changed the intake, you changed the carb positioning, and most likely vibration harmonics at the carb base, as well. And those harmonics are probably causing the accelerator pump cam follower to vibrate, forcing fuel through the squirters. I had the same issue when I went to the EFI. I ground a little off the front of my JBV-Heads adaptor and put a Motorcraft 133 on it (to clear the power valve bowl mentioned earlier), and my power off the corners improved dramatically.

The EFI manifold is one of those things around here that you either love or hate. I think a lot has to do with the rest of your set up, and track configuration, because there are a lot of successful, knowledgeable folks on both sides of that fence.

[oldracing2]

Would like to thank everyone for your information,will check the sealing and see what I can determine the problem. For now back to the old stock intake. Again thanks for the help

[that dude]

I think jatch is right about the Holley pullover, from what i've seen of your symptoms. i had same issue with holley 4412 and stock carb D-port intake. that combined with too large a squirter (nozzle).


look down the throat of the carb and rev it up and hold it at about 3000-3500 in the garage and see if you see fuel streaming lightly down from under the accelerator pump nozzle. Also look into nozzle size, your float level, vent whistle, and your accelerator pump cam color you have in it.

JBV offers a kit for this i know, if you are having pullover issues. I've personally never used a anti-pullover and don't know whats in them.