Pics of 340 or 360 heads on a 318?

billzilla · Post by **billzilla** » Sat Mar 15, 2008 4:29 pm

I'm trying to determine if my 318 has different heads on it. I have an Edelbrock intake but I'm not 100% sure it's sitting on 340 or 360 heads.

Should I take a pic? Anything I can look for?

billzilla · Post by **billzilla** » Sun Mar 16, 2008 3:26 pm

Also, I just noticed the Holley 1850 600cfm secondaries aren't even connected to any linkage! They're just wide open. This can't be good, can it?

landon1 · Post by **landon1** » Sun Mar 16, 2008 3:29 pm

i have an 1850 and idk what you mean by not hooked to linkage...at least on mine, they're vacuum secondaries, so there isn't any linkage other than a lil rod to make sure they close back up

billzilla · Post by **billzilla** » Sun Mar 16, 2008 4:04 pm

God, I am such a mechno-ignoramus. What I was seeing was the choke linkage (lack thereof because there's no choke on this 1850) for the CHOKE PLATE.

Um. Yeah.

-_-

Smellslike1974 · Post by **Smellslike1974** » Sun Mar 16, 2008 4:43 pm

I thought the only 360 heads that could fit a 318 block were custom ones.

landon1 · Post by **landon1** » Sun Mar 16, 2008 5:25 pm

idk...i think the small block heads are interchangeable....my old boss had a 360 he had bored out, but then he put some 273 heads on it thinking he could get more compression (idk if that's true or not)

um linkage for the choke...there is a rod that comes down from the choke cup, then it attaches to a plate that is mounted by a screw to a rod that goes through the carb (can't see it) to the throttle so that when you press the gas pedal a little it makes the choke closing/opening easier...you could be missing the stuff, cuz it is pretty easy to lose

Serious Satellite · Post by **Serious Satellite** » Sun Mar 16, 2008 10:20 pm

http://www.allpar.com/mopar/4bbl.html

go there. The 360 heads will fit, but compression is an issue.

The 360 heads and Intake swap will fit on the 318, but the compression will be around 7.2:1, which is not very good for performance, which is not to say that the heads cannot be shaved .050 and intake be rematched to fit, adjustable rockers added to offset the rocker geometry, and away you go.

The book says the 360 to 318 works well, but, take the 318 heads, shave .020 off the head, install 1.88 intakes vice 1.78, port the heads and you would have a better combination, especially on the bottom end response and will still rev as high as you want and float the valves before the power falls off (how can you beat that?). It can be done, but, if you have a 360, which is physically the same dimensions externally as the 318 and 273, why not go the least expensive route?

billzilla · Post by **billzilla** » Sun Mar 16, 2008 10:45 pm

Welp, I don't think I have 340 or 360 heads, but I could be wrong. I will look at my service manual later and see if I can tell. Car is in the shop for brake work (other thread).

I don't know if the .030 over bore that it has now is good for the Edelbrock Performer on there.