360 heads on 318

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phf

phf

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would i be able to make good power with a 318 bored .010 over with kb hypernautic pistons, stock i-beams, a thumpr cam and 360 heads ( casting # 3671587) an edelbrock dual plane and a holley 650cfm and mopar performance electronic distributor. a built 904 and an 8 3/4 with 3.73?
 
Not an expert on predicting power, but there was just a post on a article link for a 415 hp 318 not too far off what you have. Do a search for 415 or 415hp and it should come up. EDIT: WELL, I JUST TRIED TO FIND IF FOR YOU AND I COULD NOT GET IT TO COME UP. I MUST BE GOING LOOPY AS I'M SURE I READ IT ON THERE THIS AM.

If I remember right they put the block over .040. Used the same type piston, decked the block to make the piston flush with the block. Put larger valves in the head and just did a clean up port. Made it sound like hardly any work to porting at all. Skimmed the head I believe too. Used an RPM air gap, thermoquad carb, TTI's, Comp 268 (am I remembering right there?) cam and that is about all I remember. I do remember them using stock rocker gear. Hope that helps some at least.

Cheers
 
If the KB pistons are zero deck ones, I beleive the number may be 167s, then those heads should be OK. If the pistons are stock height then those heads will be sluggish on the bottom end because of their large chambers, which in that case you would be better off with 302 heads or magnums. Below are the specs on the 587 heads. Mike
3671587 1973-1976 340 360 1.88" 1.60" 65cc-73cc
 
i have all the parts for this build if you are interested...
 
There is that link! Wasn't that posted this AM? A good read. One hopes they did not gloss over some key points in the build as if not then that is a pretty decent build for no real fancy parts.
Cheers
 
thanks guys. as far as i know ill need to deck the block and also mill the heads to get the cr up a bit. i heard a lot of good things bout the 302 castings, but i just cant afford the bigger valves and am not too experienced with a die grinder, so i think for now ill jus mill some 360 heads down and run em for the time being. maybe later ill upgrade to a set of ported 302s with bigger valves
 
phf said:
thanks guys. as far as i know ill need to deck the block and also mill the heads to get the cr up a bit. i heard a lot of good things bout the 302 castings, but i just cant afford the bigger valves and am not too experienced with a die grinder, so i think for now ill jus mill some 360 heads down and run em for the time being. maybe later ill upgrade to a set of ported 302s with bigger valves
Click to expand...

I put in 81-83 (4027596) heads. There HP 318 heads, Cast-in 360 with valves 1.88 1.60. Chambers are 66cc-72.5cc.
There are a direct fit without any milling/decking required. Crazy bunches of upper HP, however you will lose some bottom end.
 
Thanks DusterBoy15,
Actually the 302's that we've done are supporting 500 hp + but the streetability wouldn't be realistic at this stage but 400+ would be, and the need for alot of the aftermarket parts aren't needed. A read of the 349 on the cheap is needed at this point, kind of explains the things that he wants to know (I believe).
 
valiant mike, the bottom end is not together yet, im just shopping for parts at this point and wanna have a game plan before i start spending money.

bjr racing, i have read and followed the 349ci on the cheap thread for a while and while that sounds very appetizing, im actually considering it, however the streetability factor is very important to me. like i said ive heard a lot about the 302 heads, but im not sure how much id need to spend on them for them to make as good as or better flow numbers than the 360 heads
 
If your doing on the cheap, the 360 heads will do OK and fine. It is alot cheaper than porting 302 castings. But that would be best. Not cheapest.
The thing with the 302 is not port size but speed of air flow (With fuel of course) and valve size that would work best for the intended purpose.

(Again, if on the cheap) While looking for a higher performing engine, you'll want a decent stall converter with a decent sized cam to get those 360 heads to work better. In this arena, streetablity starts go away some.
 
Rumblefish is very right, streetability will become a concern if you get a cam big enough to give those heads a workout, I have 340 j heads on a 318 myself and I looked at the 415 article with interest, they used a comp xe hl series to take advantage of the .904 lifters, but you mentioned a thumpr cam, I thought you may be interested in knowing that that is a fairly pricey setup, the lifters alone are over 400 dollars. I would like to suggest that you look at Hughes engines, they have a couple cams in the muscle car series that will give you a lopey idle but great torque off idle, and low end torque is where you will need to focus on that particular combo, this I can attest from personal experience. I used the .489 version, 219* on a 108 lsa plus 3* of timing. I can burn them all the way off the rim at this point, no bull about it. I will have some new pic's of precisely that here pretty soon!! Best of luck to you!:salute:
 
thing bout using the thumpr cam....i only pick it cuz its a hydrolic roller and ive seen flat tappet break ins go wrong.....
 
PHF,
The thing is that you'll not find a better head than the 302's for the street and low rpm HP and torque, but you have to stay with the small valves or the low end performance will be gone. This is what makes these heads come alive and work. In full ported form we have had them up at 6500-6800 rpm's and still pulling, the nice thing is that the small heads allow you to run more cam and make more use of it without any drawbacks. Just make sure that you have all the parts to match the cam and that the engine is able to utilize it.
From having large port heads and small port heads on the same engine the small port heads will have more lope to them than the large ports will, and use less fuel because they are more efficent. And the more efficent a engine is the more power it will make, reguardless of the CI. This is where having the right head on the right size engine and the right cam is where it's at. Making everything match for the engine and rpm use will give you a much more enjoyable time than one that sounds like it will run but wont.
 
are you saying i'll b able to run a bigger cam with the 302s while they hold smaller valves?
 
The thing is that the large port heads have to be turned at a higher rpm than the small heads would with the same cam, in order for the heads to become efficient. The small port heads will respond better to camshafts than the larger counterparts, basically because they are more efficient that they will have more torque and power at a lower rpm and will use less cam to get a lope which in turn makes them more streetable.
 
Plus, the 302s have a 56-65 cc chamber as opposed to 65-73cc for the 360 heads. Just by bolting them on you'll up your compression over the 360 heads with no milling heads or block. I personally would get zero deck pistons, 302 heads, port them and bolt it up. Actually thats exactly what I am doing. Mike
 
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