Single Two Barrel Question

Scotty's 52 F3

Scotty's 52 F3

Well-known member
I'm hoping Ol' Ron or JWL will chime in on this. I got JWL's book for Christmas and it answered a lot of questions I had for my build.

I was amazed that headers and dual exhaust did nothing for performance at the lower RPM range I'll be operating my truck in. Good to know, it will save me some money.

I still have the stock 8RT in my F3 but, will be building it with an EAB cam and heads. Not sure of over bore yet or if I will stroke it. If I find a good deal on a 4" crank I probably will. So basically a little more displacement and compression, stock EAB cam, 3.73 gears and 32" tires. Looking for all the torque I can squeeze out of it.

It looked like dual carbs or a small 4 barrel did improve torque around 2000-2500 RPM. (In the book)

Will my stock Holley 94 restrict power at all? I see there are slightly higher flowing Holley 94's available.

What about a 4 bolt Merc manifold with a small base Rochester 2G?

Another thing not really mentioned is the stock oil bath air cleaner. Does it restrict power on a slightly modified engine?
Scott
 
If you run the merc intake with a 2G (or any of the 4 bbl intakes) you will need a new distributor as the factory unit needs the vac. signal from the holley 94. Ford did build the 94 style carb in later years with 1 1/16 venturi rather than 15/16 if that helps you any. You will have to check throttle plate clearance on your intake if you go this route but will not have any vac. issues with the factory distributor.

For air filter, I removed the oil bath guts from a shoebox car air cleaner (little bigger style than the "RT" truck cleaner) and put in a K&N; looks all stock on the outside. Perhaps you could find a K&N that would fit down inside the "RT" base and try that route.
 
JHFORD51 said:
For air filter, I removed the oil bath guts from a shoebox car air cleaner (little bigger style than the "RT" truck cleaner) and put in a K&N; looks all stock on the outside. Perhaps you could find a K&N that would fit down inside the "RT" base and try that route.
Click to expand...

JH - What is the number of the K&N Filter you used? I would like to do this on my '53....
 
petehoovie said:
JH - What is the number of the K&N Filter you used? I would like to do this on my '53....
Click to expand...

I'm running 4 K&N 4in. tall on my 40 and 3 K&N 6in. tall on my dragster, I'll get the part no. tomorrow when I go out in the shop. They fit on the top of the 94 and 97s with a hose clamp. They are the best filters for not robing air and can be cleaned.
 
Thanks for the replies. I guess that answers the air filter question. The stocker is restrictive.

I know about the distributor issues. I have a couple to address that.

So what is the verdict on the carb? Should I start looking for a larger two barrel or is the stock 94 OK?
 

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I think the stock two barrel will feed the engine in your truck just fine. I think Ol' Ron has mentioned knowing of an Ardun with multiple carbs that is really only running on the center 94, and it apparently still runs strong.
 
I like the 2GC, The CFM is just a bit more than the 265 cubic inch 59AB can use- according to what I've read... It's simple, I just bolted it on and it seems to have been jetted just for me... (From a swap meet, $5 or so)
My mileage is all over the place cause of the useage, but on the last long (250-300 mile)
day, I got about 20 MPG. I was shocked.

Karl
 
The 2GC the cfm is a bit more than 265 cube 59A can use? Is that what you ment? Cus that ain't so,
From experience, going from a single 94 to dual 94's made a real noticeable improvement when the power valves value is corrected. Even with a Navarro racing dual with no heat, it had better pull everywhere in the rpm range. This is not a dyno test, but a seat of the pants/tire smoke/smile inducing/it easily beats the same car it couldn't catch before type of test.
The 2cg isn't to big cfm wise, in fact it's only a bit bigger cfm wise than a regular 94. I know the throttle plates are big, but look at the junk in and above the air horn. Compare its shape and messyness to the much sleaker 94 air horn.
A Big thing to remember, the cfm rating for the 2cg is measured with a 3 inch depression (as is the norm for 2bbl carburetors), the published or most repeated cfm number for the 94 family and 97 family was measured with a 1.5 inch depression (the depression that 4 bbl's are tested). This obviously skews the numbers favourably to the 2cg. The true difference is surprisingly close, at least surprising when you judge purely by the throttle plate size difference.
There are formulae for getting a 3 inch depression from a 1.5 inch depression, can't grab one now as I'm off out the door to eat a hog, should get one on line. This will give you a calculated 3 inch number, not a measured number, but until someone does the testing, that's all we got.
Martin.
 
If you decide on a stock look here is a modified 8rt oil bath housing with the internal filter removed. Napa filter is inserted and sets snug into the base. The top that covers the filter is not shown, but it would seal the filter into the housing and is held down by a 1/4-20 wing nut.

Walts idea is perfect. I like the K&N filters and run one on my Carter WCFB under a chrome Cal Custom cover.
 

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I actually don't mind the oil bath maintenance. It must work because the intake is spotless. Absolutely no dirt or dust. I see dust on my modern intakes with K&N's.

I wanted to know if they are restrictive on a SLIGHTLY modded engine. If not, I'll use it as is. If it is, I'll probably convert it.

Same with the stock Holley 94. Most seem to think it will be fine. Yet, others think slightly bigger would be better. I don't know as this is my first flathead.
 
Scotty's 52 F3 said:
I wanted to know if they are restrictive on a SLIGHTLY modded engine. If not, I'll use it as is. If it is, I'll probably convert it.

Same with the stock Holley 94. Most seem to think it will be fine. Yet, others think slightly bigger would be better. I don't know as this is my first flathead.
Click to expand...

This stuff is all RPM dependent, at lower RPMs it is not going to make much difference. At higher RPM it does start to make a difference. This will all depend on how you are going to be driving it, a lot of high RPMs then worry about it, if not you are better off leaving it as is.
 
Bore, stroke and increase compression. EAB cam and heads, mild port and bowl cleanup. Wasn't sure if increased displacement would exceed capability of stock carb and oil bath.

Sounds like I'll be saving a bunch not needing headers, intake and carbs. The extra torque from more cubes and compression will be nice.

Thanks again for the feed back. Scott
 
Scotty's 52 F3 said:
Wasn't sure if increased displacement would exceed capability of stock carb and oil bath.

Scott
Click to expand...

It will increase the CFMs through the air cleaner some, but it is still mainly an RPM issue. The stock system has plenty of capacity for the lower RPM range. I will have to look, I'm not sure if JWLs book has much on air filters or not.
 
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