[PontiacLars]

I have FiTech EFI on my engine. My Butler dropbase shaker assembly do not fit on this unit because it sits to low and hits the housing and fuel lines.

I have looked at using Spectr 98499 with a 4" pipe and K/N air filter placed away from the engine heat.
I read online that this air inlet is very restrictive and engine loose significant horsepower. Any input on this?
I would belive that this setup feeds the engine much cooler air than an open filter element on top of the throttle body.

[steve25]

How much extra upward lift would the Butler set up need to have clearance?

Got some photos?

[Formulajones]

Youve run into a very common problem that seems to come up all the time on the Holley forum.
I'm not sure what provoked these companies to make a throttle body that won't accept OEM air cleaners with odd fuel line locations and throttle linkages that stick out too far but all the manufacturers of aftermarket throttle bodies are guilty of it.

It's why I chose the Holley stealth unit that looks like a Holley carb, everything fits.

I don't know of a real solution for your situation but there are a lot of fitech users out there, I'm sure some good suggestions will pop up that hopefully keep you from having to cobble things together. Jlmounce likes and uses fitech, he may have a good suggestion

[Cliff R]

You'd think that working from a clean-slate the folks making those electric carburetors would at least make sure that EVERYTHING fits during the install without "cobbling" up a bunch of stuff to get them in place.....DUH?

It's been like that with a lot of aftermarket parts related to intakes and carburetors dating clear back to when I got into the hobby nearly 50 years ago.

I chuckle to myself at local car shows when we walk thru looking at the "cobbling" folks go thru to run an Edelbrock RPM air gap intake and one of those POS AFB or AVS clone carburetors. Hack sawed fuel line with 3' of exposed rubber hose held in place with a couple of hose clamps while it 's laying on all sorts of stuff as it makes its way to the carburetor. Drop base and low profile air cleaner set-ups that rob WAY more power than the taller and bigger intakes every hoped to gain.

We're not seeing too many electric carburetors as of yet. I actually sponser one of the bigger car shows locally and walk thru looking at all the entries. Edelbrock has the market cornered here. If there are 200 cars in attendence 200 will have an Edelbrock AFB clone in place, 2 or 3 the AVS clone, and all but a half dozen left will be using a Holley carb of some sort.

It simply comes from being a little off the grid here, dirt poor farming community and nearly everyone in the hobby in these parts is looking for the cheapest thing in the Summit catalog that will move their ride from point A to point B......FWIW......

[JLMounce]

The problem with that Spectre unit is that it destroys the airflow through the throttle bores. Even with the FiTech and Sniper, the venturi through the throttle bores behaves the same as a carburetor. Straight, laminar flow through the throttle bores fills the plenum in a way that shortens the turn from the bottom of the throttle bores to the runners.

While yes you may be grabbing cooler air for the engine to use, the way in which the air is being used is much less efficient. The hat is simply too close to the throttle bore entrance and it disrupts the flow of air. From a power perspective, you're better off taking hotter air from a traditional style air cleaner.

On my FiTech unit I use an edelbrock 3" gauze filter with filter lid. It's not really a drop base, but the design is such that the total height from carb flange is only 3.5", which is among the shorter options available without custom modification.

[HWYSTR455]

There are hat companies that make ones that flow well. I think the biggest issue is the filters. The cone type filters have some pitfalls in design.

Not sure what's considered 'significant' horsepower, but have heard some say in personal testing that 20-30hp ranges have been seen.

Personally, I would think it would be best to value in percentage, but believe after X, it can drop off faster. So larger displacement engines would see a bigger drop compared to smaller displacement engines.


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[65madgoat]

Unsure where it hits on the body, but have you tried these fuel fittings for more clearance? Helped me fit with my drop base air cleaner:


https://www.purechoicemotorsports.co...cat/cat171.htm

[EFI Pontiac]

Try Universal Spinners ! Real Nice set up ! They are out of Canada . I am using one and works great . Absolutely no difference with it on or off on a Chassis Dyno .

[Cliff R]

"Not sure what's considered 'significant' horsepower, but have heard some say in personal testing that 20-30hp ranges have been seen."

I've done some testing in that area and it's true. When you go up with the intake and stick the carb closer to the hood often a drop base air cleaner is required. Nothing at all wrong with that except you MUST have a minimum of 3" from the flange where the air cleaner base sits to the bottom of the lid or there will be a performance loss.

Even worse I've ran into scenarios where the engine would stumble/hesitate or even "puke" all over itself going quickly to full throttle even if it pulled pretty decent after it got thru all that. Remove the lid completely and they were fine.

It's an area where few folks do any testing much past "seat of the pants" so they never know how much power they lost adding a spacer, high rise intake, or both when it required moving the air cleaner lid closer to the carb to get the hood closed......FWIW....