65 273 Intake manifold

[wheelsport]

Sometime in the near future I'm going to install a Edelbrock Performer manifold on my '65. Edelbrock recommends leaving the manifold ports as manufactured because of intake velocity. Should I port the heads to match the manifold or leave them alone?

 

[Professor Fate]

You do realize that the intake manifold bolts on a '65 are at a different angle than on the Performer, which is designed for the different '66 and later bolt configuration?
As far as the ports go, I would wait and see what the manifold looks like when you get it. You may want to clean up some of the casting imperfections, but I would match it up to the heads with an actual 273/318 intake gasket (not the 340/360 sized gasket- because since you didn't say, I'm assuming we're dealing with a '65 273 motor) and maybe do a little gasket matching. But, it's a moot point if it's a '65, since the manifold won't fit. Start looking either for some '66 and later 273/318 heads, or a Commando/Charger or old Eddy D4B 4bbl. manifold to fit your '65 heads.

 

[dano]

Hello from across the river!

Tell us more about what is going on with your engine. i.e. your building it now, its in the car, its completely stock, its a swapped 360, etc. Anything to help us guide you better.

What the Professor states is true. So if your engine is the original as far as you know then you need to verify if you have 1965 and down heads.

 

[seabee]

But, it's a moot point if it's a '65, since the manifold won't fit. Start looking either for some '66 and later 273/318 heads, or a Commando/Charger or old Eddy D4B 4bbl. manifold to fit your '65 heads.

To be clear, are you saying a Performer intake won't fit heads with the early bolt angle?

 

[Professor Fate]

To be clear, are you saying a Performer intake won't fit heads with the early bolt angle?

The gasketed surfaces match up, but not the bolt angles.
People have "made" them fit, elongating the bolt holes to the different angle, and using wedge-shaped washers under the bolt heads to accomodate the different seat angle for the bolt heads. You also need to consider using sleeves on the bolts to accurately align to the ports, since the '65 and earlier (in addition to the different bolt angle) used 5/16 intake bolts as opposed to the '66 and later 3/8" intake bolts. Not using some kind of sleeve on the bolts allows excessive fore & aft movement of the manifold, allowing for port misalignment.

 

[rumblefish360]

To be clear, are you saying a Performer intake won't fit heads with the early bolt angle?

Correct. The intake bolts on the earlier engines are smaller and are drilled into the cylinder head at a different angle.

Can it be made to work? Yes.
Will you be happy doing the work? Probably not.

 

[wheelsport]

Looks like I made a mistake buying the manifold. Its a running car with the original engine. Just wanted to get rid of the troublesome 2 barrel.

 

[rumblefish360]

Put it up for trade for a factory 4bbl. intake or an old aluminum intake for those heads.

 

[dano]

Looks like I made a mistake buying the manifold. Its a running car with the original engine. Just wanted to get rid of the troublesome 2 barrel.

Maybe not as a previous owner could have had the engine or heads replaced. Can you attach a picture of the engine, maybe a close up of where the bolts attach the intake to the head? What is the casting number on the intake? That might point to what you have.

 

[seabee]

Looks like I made a mistake buying the manifold. Its a running car with the original engine. Just wanted to get rid of the troublesome 2 barrel.

Maybe not, like the guys said above it takes some attention to detail to make it work but I have had an early 273 with a Performer that worked fine for many years as a daily driver.

 

[pishta]

early bolt angle, found this tonight looking for something else in my picture drive...Early bolt angle is not perp to the head like the 66 and later intakes. It can still work, you just have to put a 3/8 drill into the manifold bolt holes and lean on the drill, then run a washer on top under the original 5/16 bolts. Looks ugly but itll seal. Easier to get 318 heads, 302's at that!

 

[pishta]

Dibbons 66 intake, look at the modern bolt angle.

 

[66fs]

Looks like I made a mistake buying the manifold. Its a running car with the original engine. Just wanted to get rid of the troublesome 2 barrel.

Easy to tell, do the intake bolts use a 1/2" wrench or 9/16" wrench? 64 and 65 original heads use the 5/16 bolts and 1/2" wrench at the non standard angle.

 

[wheelsport]

The intake bolts are 5/16". The casting number underneath of the manifold is 3475 & on the top left front S-P 2-P 318 is cast on the top of the runner. I'm sure I can make this work. I've made a lot things work that weren't supposed to, in my 70 years of working on cars.

 

[Professor Fate]

The intake bolts are 5/16". The casting number underneath of the manifold is 3475 & on the top left front S-P 2-P 318 is cast on the top of the runner.

A pic would be nice-
Is it like this?

If so, you've already got an aftermarket (Edelbrock) 4bbl. manifold, if you have a 2bbl carb on it, it must be using some kind of an adapter plate.

And if you do have the 5/16 intake bolts, it must have been modded already...?
A factory manifold would be cast iron, an SP2P is aluminum.

 

[66fs]

So you have 65 273 heads and an Edelbrock SP2P economy intake for 66 up heads. You can make it work with tapered washers.

Also RRR was selling a good 2 barrel carb. [SOLD] - Carburetors For Sale

 

[dano]

I have used these in off angle situations. Likely not room on an intake install though.

McMaster-Carr

Pics of what you have to work with would be good.

 

[66fs]

I was thinking of these. I think they are about 9.5 degrees and will get you pretty close.

McMaster-Carr

 

[wheelsport]

Professor,
That's a picture of the manifold I am installing. I appreciate all the advice.

 

[Professor Fate]

Professor,
That's a picture of the manifold I am installing. I appreciate all the advice.

Okay, I thought you said you were installing a Performer; the pic is of an SP2P.

 

[wheelsport]

I'm installing a SP2P 318. Its an older Edelbrock manifold. I assumed it is a performer. It looks like one.

 

[wheelsport]

Update on this SP2P 318 manifold. I appreciate all the feed back I have received about installing this manifold. I have looked the manifold over very closely and have found it to be all original with no modifications as to bolt holes and such. This is a numbers matching car built on 9/17/1964. To my knowledge the heads are original to the engine. Today I test fitted the manifold on my early 273. Fortunately, the manifold fits perfectly with all bolts at the proper angle corresponding with the manifold. I'm not sure but, could I have an Edelbrock manifold made for the 273 or possibly later heads? If the heads are from a 318, is there a way to find out? Thanks again.

 

[66fs]

Pull a valve cover and get us the last 3 numbers of the head castings.

 

[wheelsport]

These casting numbers are on both heads. There is a pair of numbers on the heads.
2465315-2 & 09124

 

[66fs]

These casting numbers are on both heads. There is a pair of numbers on the heads.
2465315-2 & 09124

Those are 64-65 273 heads. I'd get the angle washers and install that manifold. Do not use the steel shim intake gaskets. You should be fine.