360 Aftermarket Heads on 318

Mopar Millenial

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What are 920 heads and what do they come from (model/years)?
From what I know, take that what it's worth... should be from the 2658920 head casting number. The 920 obviously the last 3 digits seems to have come from 67 and works with 273 and 318 LA motors. On the other hand for me I have 675 heads which is the 2843675 casting number fitting 318's from 68-74 (my block was replaced with a 1970 318 long before I got it).
 

mgoblue9798

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I agree it's too big, I'm hoping to combat that with better air flow that crams more air into the cylinder since the intake valve doesn't close until 44* ABDC. But I'm just trying to make some solutions with out swapping the cam completely. personally I think a 340 or 360 intake with 360 heads could solve most of that...hopefully. lol
Thanks for the response!
Unless you are racing the car, do yourself a favor and replace that cam with one more appropriate when you install your Edlebrock heads.
 

Mopar Millenial

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Unless you are racing the car, do yourself a favor and replace that cam with one more appropriate when you install your Edlebrock heads.
I got a dumb question… say I get some flow numbers on whatever heads I end up with, 360 aluminum, ported 318… etc. what would getting a less aggressive cam actually do. I mean sure it’ll raise manifold vacuum since the one I have now only gets 10-12. It’ll idle smoother sure, sound probably smoother and less choppy. But what’s the benefit? Better mileage? Would I get better drivability? I mean I’ve taken it 30 minutes down the road didn’t seem to be any different. Just wondering in a practical sense.
 

mgoblue9798

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I got a dumb question… say I get some flow numbers on whatever heads I end up with, 360 aluminum, ported 318… etc. what would getting a less aggressive cam actually do. I mean sure it’ll raise manifold vacuum since the one I have now only gets 10-12. It’ll idle smoother sure, sound probably smoother and less choppy. But what’s the benefit? Better mileage? Would I get better drivability? I mean I’ve taken it 30 minutes down the road didn’t seem to be any different. Just wondering in a practical sense.
Better drive ability. better mileage, and more torque/power in the rpm band you use on the street.
 

rumblefish360

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I got a dumb question… say I get some flow numbers on whatever heads I end up with, 360 aluminum, ported 318… etc. what would getting a less aggressive cam actually do. I mean sure it’ll raise manifold vacuum since the one I have now only gets 10-12.
It may, it may not.
It’ll idle smoother sure, sound probably smoother and less choppy.
Not really. Both above quotes depend on how the cam is ground.
But what’s the benefit? Better mileage? Would I get better drivability?
Probable mileage gains. Possible better drivability. Depends on how the cam is ground.
I mean I’ve taken it 30 minutes down the road didn’t seem to be any different. Just wondering in a practical sense.
The main thing about the cam is where it performs in. This is dictated by the duration. What rpm do you want the car to perform in?

The cams lobe separation angle is often put on a 110. Going numerically lower adds a rougher idle and lowers vacuum. BUT it adds low end torque and normally peaks sooner.

Just the reverse going to a 112 or greater. Idle smooths out and you loose a lot of torque. Not just on the low end but normally through out the curve.

The Edelbrock cam is designed to be a no complaint driver cam. Best used in automatic transmission cars. The cam has a low lift and takes very little advantage of there cylinder head.
 

rumblefish360

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That 7177 is too big for a 318. The duration is 300/310, if it's a hi revving bracket car maybe. JMO 65'
Check the duration @.050 and you’ll change your mind much less look at any other spec of that cam. You’ll actually probably throw it away as garbage.
 
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