Early 352 heads with machined chamber

[pclowes]

Does anyone have an opinion on the use of early 1958 352 interceptor EDC-E heads with machined chambers?  I am planning to use these on a fairly mild 390 street setup in a 58 Ranchero.  Planning on using a new Edelbrock Airgap dual quad setup with solid flat tappet cam with around 280 degrees advertised duration with a 108 LSA . Will run a BW T89 3 speed with OD and 3.70 gears. Tube headers also.
 
Started over 30 years ago on this combo. ( actually at that time is was to be much milder with a mild Erson hydraulic grind and a Dual Port Offenhauser manifold ) At that time I had purchased TRW pistons that would provide around a 10 to 10.5 CR depending on how the chambers CC'd out.  I like to play with the obscure but am concerned about the streetability of these heads with pump gas.  I know the easiest way out is to just go the Edelbrock Aluminum head route and know they will easily give more power.  At this time I am ok with the power potential being down. ( Actually concerned about overpowering that old 3 speed.)  I also know that in 1958 these heads were good for 300hp in stock form on a 352 so I feel there is some performance potential especially with some mild port work.

I am thinking the larger overlap that would come with the cam selection that I am considering would negate the possible higher compression ratio problem that I have mentioned.  Anyone have any thoughts on this?

[fekbmax]

If only the eldebrock would take Holley carbs.
I remember looking at the old PAW catalogs at all the Offy stuff for the FE. Good stuff back in the early 80's .

[jayb]

I think you'll be fine with those heads, and that compression ratio, as long as you pick the right cam.  I'd be much more concerned with the intake valve closing point than the overlap; that is what is going to determine how knock sensitive the engine is.  I made some assumptions and did a quick dynamic compression ratio calculation, and with a static 10.3:1 compression and the cam installed straight up (108 ICL), your DCR comes out to 8.0:1, which should be OK on pump premium fuel.  More advertised duration would let you advance the cam some, and it is important to note that if your compression ratio is off of what you have stated, you could have trouble.  Make sure to measure the chamber, be certain of the relief volume in the piston, account for the head gasket, etc.

[gdaddy01]

I run 1961 hi po 390 with the small chambers , with a 270 s comp cam , top loader , 300 gear in a 62 ranchero , 92 octane , two four on a edely air gap , no problems . I agree , should have made intake for hollies . 

[pclowes]

Thanks to all for your help! I am a first timer on this site and was actually wondering if I would get any response at all.  I am pleasantly surprised.

gdaddy01 that's good to know that you are running almost the same setup with good results.

Jay your advice on the intake closing spec made me realize that I was thinking one thing and calling it another. Makes total sense and has me researching static and dynamic CR.  I will definitely follow your advice and thoroughly check everything.
I thought that your name looked familiar and, I was right, I have your great book on FE manifolds in my library. Even though I like the old stuff, that book is the reason that I didn't waste my money on an used Offy dual quad manifold and, instead, decided to go with the new Edelbrock.  I, like so many others, thought that the Offy would be reasonably close in performance to anything new out there for a low riser application, but was I surprised after reading your test results.  ( I had that exact Offy manifold in my hands at the Long Beach swap meet and decided to wait until after I bought your book) I reviewed all of your test results on 2x4 manifolds and the new Edelbrock has the most performance potential for what I can afford even though it does not have the same nostalgiac vibe. I'll get over that, I'm sure, the first time that I drive it. 

fekbmax I, too, am disappointed that the new Edelbrock does not have the spacing for Holleys ( I actually wanted to run two Autolite 4100's. Sounds nuts I know. I said I like the obscure. ), however I wonder if the carb spacing has something to do with it's good performance.  Probably not. It was most likely a way for Edelbrock to sell AFB's ( they'll always be AFB's to me.... never felt comfortable calling them Edelbrock carburetors.)

Thanks again for a great introduction to fepower.net.

Phil

[FElony]

Thanks to all for your help! I am a first timer on this site and was actually wondering if I would get any response at all.  I am pleasantly surprised.
Phil

We'll see if you make it through the first 30 days without permanent emotional scarring. If you fail, we'll tie you to the bumper and drag you around a little bit. If you are successful, you can join our gang, with a car code and blood initiation and all that.

https://www.youtube.com/watch?v=CgZTVkjQwto

[pclowes]

I am a member of another Ford site (non FE) whose name I won't mention.  Believe me, if you can survive that you can survive anything.
So far so good. You guys are great!

[66FAIRLANE]

( I actually wanted to run two Autolite 4100's.  Sounds nuts I know.  I said I like the obscure. )

I think that sounds like a great idea! Hope you do it. Let us know.

[RJP]

My .02... and worth every penny. My opinion of the early machined combustion chamber heads is they do not have enough quench area to make much difference in detonation suppression. If you look close you'll see a very small area that is suppose to be the quench pad. Other than that they are ok heads. I ran a pair on a 427 center oiler for about 12 years in my 61 Starliner. I didn't experience any problems but it was never raced, just driven on the street and seldom saw WOT. Also back then gas was a bit better too.  IMO I would choose a cast chamber head such as a C1AE or a C4AE head over the mach. chamber head.

[pclowes]

My .02... and worth every penny. My opinion of the early machined combustion chamber heads is they do not have enough quench area to make much difference in detonation suppression. If you look close you'll see a very small area that is suppose to be the quench pad. Other than that they are ok heads. I ran a pair on a 427 center oiler for about 12 years in my 61 Starliner. I didn't experience any problems but it was never raced, just driven on the street and seldom saw WOT. Also back then gas was a bit better too.  IMO I would choose a cast chamber head such as a C1AE or a C4AE head over the mach. chamber head.

You know, that small quench area is also what first caught my attention but I have to admit I don't know and understand all of what I'd like to know about quench/squish.  Also the quench area in 427 hi riser heads and also Tunnel Port heads seems about the same size as the heads that I've been talking about.  Don't know what that means other than we all know how the 427 heads perform and that I need to learn more about the subject. Of course, like you said, fuel was a lot better back then.

[pclowes]

( I actually wanted to run two Autolite 4100's.  Sounds nuts I know.  I said I like the obscure. )

I think that sounds like a great idea! Hope you do it. Let us know.

Unfortunately, they need the same space as a Holley so they won't fit either.  Maybe sideways, but wouldn't be too streetable. If I decide to spend the big bucks (about twice the price of the new Edelbrock) and buy one of the old Ford manifolds I'll use the Autolites.  They will also fit on the Offie and the old Edelbrock but, as I found out, the performance is not there with either of those setups.

[Falcon67]

IMHO - running two Ed 500s or 600s will do just fine, as they have as efficient - or more so - primary boosters than the annular discharge 4100 style, plus they have less tuning hassles than the Holleys.  I run plenty of Holleys and Holley clones, but the Eds also work very well even in race applications.  Especially in a dual setup.  The only downside I've found to the 14xx "Performer" Ed carbs is that there is no tuning for the secondary tip-in.  That could be important for my street/strip bracket car, no so much for a mild street build.  I've run 2 Eds on a tunnel ram on the current 302 and they MPH exactly the same - meaning they make the same power - as a single 650 DP Holley.  Limiters on this engine are cylinder head flow and cam.

[pclowes]

IMHO - running two Ed 500s or 600s will do just fine, as they have as efficient - or more so - primary boosters than the annular discharge 4100 style, plus they have less tuning hassles than the Holleys.  I run plenty of Holleys and Holley clones, but the Eds also work very well even in race applications.  Especially in a dual setup.  The only downside I've found to the 14xx "Performer" Ed carbs is that there is no tuning for the secondary tip-in.  That could be important for my street/strip bracket car, no so much for a mild street build.  I've run 2 Eds on a tunnel ram on the current 302 and they MPH exactly the same - meaning they make the same power - as a single 650 DP Holley.  Limiters on this engine are cylinder head flow and cam.

You're right,  just won't look as good.  I am actually going to run a very old version of the AFB that has a diaphram that activates the secondaries instead of the airvalve and weighted butterflies.  Because the diaphram hangs from the back of the carb, the only way to fit them on the Edelbrock manifold is to remove the diaphram from the front carb.  I plan to run both secondaries from the diaphram on the back carb with some home built linkage. May have to change the spring tension?  Should be interesting.  I also like beating my head up against a wall. LOL
This early AFB (2640 SC) was the carb that was originally on the 352 Interceptor in '58.