360 head on 318

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7174duster

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I was planning to put some stock 360 heads on my 318 and was wondering what was involved with it,can i just put the 360 heads on as if i were putting another set of 318 heads? Can i use the 318 head gaskets?Any fabrication needed? I'd like as much info as possible,thanks for any help :thumblef:
 
You would have to change the intake as the runners are larger and use the 360 head and intake gaskets. You'll lose compression thou because of the chamber size, 8ccs different. Other wise you into machining the heads at the deck and intake sides. The ports will cause you to lose velocity and torque in the 318 engine, as the engine can't stand this much stock.



BJR Racing
 
if it were me I would either get a good flatop piston or shave the heads to get good comp. If you shave the head you must also shave the intake. Get new 360 head and intake gaskets and a;lso a 360 intake. It is a good plan due to the bigger valve on the 360 heads. If you got to Kieth Black piastons website they have a comp calculator. Also if I were you I would get a head gasket that is the closest possible to your bore size so not to lower your comp. http://kb-silvolite.com/calc.php
 
Duster, Do you want to use 360 LA heads or 5.9 Magnum heads? I have read articles and books about the positive benefits of putting magnum heads on an LA
block. I have also read negative comments about the swap. I'm now confused. I was planning a Magnum head on a LA block build myself. I've allready purchased intake, valve covers, lifters, pushrods, valve springs, and keepers. I've got about
$900 invested and I haven't bought a cam, timing set, or gaskets yet. Is there any of you guys that have done this combo? Thanks in advance!!
toolmanmike
 
thanks for the help,i have the performer intake,cam,and 600cfm carb on the 318 and i just want to use this setup temporarily while i build the 360,would it run better with the stock 318 heads and the 4 bbl intake/carb?
 
7174duster, you'll probably be happier keeping the 318 heads on there. As Bobby mentioned, with the 360 heads you'll loose some compression ratio and you'll also loose velocity in the heads due to the larger ports and valves. Basically what this means in every day driving is that it will loose a lot of snap on the bottom end, and that's where you need it for the street. If you're planning to build a 360 anyway, keep your present 318 combo until the 360 is ready. Then you'll see some real horsepower and torque increases over the 318. Good luck.
 
OldVart said:
7174duster, you'll probably be happier keeping the 318 heads on there. As Bobby mentioned, with the 360 heads you'll loose some compression ratio and you'll also loose velocity in the heads due to the larger ports and valves. Basically what this means in every day driving is that it will loose a lot of snap on the bottom end, and that's where you need it for the street. If you're planning to build a 360 anyway, keep your present 318 combo until the 360 is ready. Then you'll see some real horsepower and torque increases over the 318. Good luck.
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Well, if i may chime in here. I have J-Heads on my 318, and 9.7:1 Compression ratio. The heads and the intake face of the heads have been milled. Untuned and ive since changed a couple things it dynoed at 240rwhp/270ft/lb. I'm quite sure that its more than that now, the motor cost me a total of about $1500 to completely build including getting the heads rebuilt, new valves, 3angle valve job....so i'm not doing too bad in the bang for buck category.

It is a daily driver, and there is no lack of 'snap' on the bottom end in my opinion, however the 3000stall converter and 3.91s will help that out...

If you are trying to use 360 heads on a 318, then the same heads on a 360 it will really not work. Becuase you'll need to mill the heads pretty good to get the compression up, as where you wouldn't on a 360..,which would have the 360 with some darn high cr. Just my .02cents

-Mike
 
GoodysGotaCuda said:
It is a daily driver, and there is no lack of 'snap' on the bottom end in my opinion, however the 3000stall converter and 3.91s will help that out...



Just think if you did the same thing to the 318 heads?
The 318 heads are faster than the 360 heads on a 318 in the same shape, but with the 318 valves not 360 valves.


BJR Racing
Click to expand...
 
Goody, with your combination you will get good bottom end, because as you stated, you have 9.7:1 CR, 3000 Stall, and 3:91 gears. This actually means that you overcome any low RPM torque losses by getting quickly into your powerband RPM with the converter and gears. With stock 8.?:1 CR, a stock converter, and probably stock gears in the 2:96 range, the 360 heads would make it a pooper on the bottom end. You've put together a well planned combination of parts and they work well for you. :)
 
BJR Racing said:
GoodysGotaCuda said:
It is a daily driver, and there is no lack of 'snap' on the bottom end in my opinion, however the 3000stall converter and 3.91s will help that out...



Just think if you did the same thing to the 318 heads?
The 318 heads are faster than the 360 heads on a 318 in the same shape, but with the 318 valves not 360 valves.


BJR Racing
Click to expand...

Yea but i paid $0 for my j-heads, and they were milled. New seals, new valves and a valve job is all i did to them...and valve springs to match the cam :thumblef:
Click to expand...
 
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