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413 build ideas

413Polara

413Polara

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Hey looking for ideas and inspiration. I’ve got a 1965 413 in my 1964 polara and plan on changing some things around. Car will likely never see the drag strip but I would like it to be a fairly mean street machine. From what I was told the motor was bored .030 over when rebuilt 20 years ago. No real info on the cam other then it’s a little hotter then factory. No idea on head work either. Intake is currently an offenhauser 360 which I’ve been told isn’t the most sought after for performance, and it does have a set of hedman headers on it into 2.25” exhaust. What’s everyone else running with their 413’s? Any ideas or pictures are welcome, thanks in advance!

IMG_3476.png
 
I’d def look at different manifold if you’re after more power.

What carb is on the engine now?

Rear gears?

Converter?

If you get curious, pull a valve cover off and get the casting number off the heads.
 
That sounds like the 413 I had in my 63 Savoy, 50 years ago. It would wake up a lot with today's tech. Just build it like a mild 440.
Mike
 
We swapped an Offy 360 for a Eddy Performer RPM on a 440 with a .530 cam, headers, roughly 10-1. It was worth 8 tenths in ET. That offy 360 is probably worse than a stock intake. Along with Dwaynes questions I'd do a compression test on a few cylinders to get an idea of the current cylinder pressure.
Doug
 
PRHeads said:
I’d def look at different manifold if you’re after more power.

What carb is on the engine now?

Rear gears?

Converter?

If you get curious, pull a valve cover off and get the casting number off the heads.
Click to expand...
Carb is currently a summit 650, not sure which exactly it is. It’s got 3.23’s with an open diff currently. Plan is for a set of 4.10’s and a sure grip in the spring. Converter is also a mystery, tranny was built years ago from what I was told and it does have a shift kit in it but again the info is pretty vague unfortunately. Is there a specific casting number on the heads that’s more desirable then others?
 
dvw said:
We swapped an Offy 360 for a Eddy Performer RPM on a 440 with a .530 cam, headers, roughly 10-1. It was worth 8 tenths in ET. That offy 360 is probably worse than a stock intake. Along with Dwaynes questions I'd do a compression test on a few cylinders to get an idea of the current cylinder pressure.
Doug
Click to expand...
I was looking at the edelbrock stuff but wanted to get some input here before I pulled the trigger on anything, thanks for the info.
 
413Polara said:
Is there a specific casting number on the heads that’s more desirable then others?
Click to expand...
Correct. Over the 20 yrs of bigblock production, there's many different variations of cylinder heads. Some are good for some things.. some are good for others
 
If it has the original trans an input shaft it will be a 19 spline. Converter selection will be limited. It can be converted to 24 spline fairly easily using a 67-70 input shaft components.
Doug
 
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