Will 4 hole spacer, 2 hole, or one hole spacer work better w/ edelbrock performer dual plane?

Think I installed 2 hole FWIR.

 

open spacer

 

Hmmm...maybe I will look use a bent probe or something (?) to determine which I installed. Guess that's doable? Runs good just curious.

 

An open spacer might give you a little more top end by virtue of each manifold plane being able to share some of the flow from the 2 barrels that normally feed the other bank. There may be a small airflow benefit from the air and fuel not having to make quite as sharp of a turn going into/through/out of the plenums into the runners themselves.

Your metering signal will not be quite as strong - I think that means that you'll be slightly lean and that tip-in response might be a little "lazy". Some carb adjustment may be necessary since carbs "out of the box" generally aren't calibrated with spacers in mind.


Norm

 

I don't get the so called "out of the box" carbs.

No one size fits all for carb tuning far as I know.

I know I had to tune my "out of the box" carb.

 

why get that when you can get this for $10 cheaper and in black rather than ugly orange/peach whatever that color is

http://www.summitracing.com/parts/EDL-8711/

 

Aluminum conducts heat a little over three times as fast as iron does.

Although it requires more heat per unit mass to heat up, it's also less dense than iron. In relative terms here, assuming that the overall volums of metal are similar (numbers are from the engineering toolbox site)

iron = 0.11 * 7850 = 863.5
aluminum = 0.22 * 2712 = 596.6

What that means is it takes more heat to warm up the iron to begin with (which takes a longer engine running time), and due to its poorer heat conductivity it takes longer for that heat to evenly flow into all of the iron and get it to reach its steady-state temperature (aka fully warmed up). Sound like what you've observed?


If the heat passages in either head or in the manifold are clogged or caked with carbon, you already have restricted crossover flow (or perhaps none at all if any of them are caked completely solid with the stuff). If you do have any flow, there's a layer of carbon/soot that's acting like insulation, making the rate of heat flow into the iron that much poorer. Your intake gaskets are also insulators rather than good conductors (so not much help there), and the manifold bolts aren't going to be very helpful either. That leaves you with hot oil splashing against the underside of the manifold being the only significant source of heat, same as what you have with the aluminum manifold and a blocked crossover. And maybe a little heat coming from reversion pulses backing up into the intake from the cylinders during valve overlap.

Norm

 

I'm looking to do the exact same mod on my '65 2V. Can you tell me more about the carb and intake you purchased (Model, from where, etc)?