302 heads-Is it worth putting them on a stock 318

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lee g

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I have a little 318 that is totally stock and I have an opportunity to purchase a set of 302 swirl port heads for a reasonable price. Is it worth installing them on a totally stock 318 for a slight compression bump and flow? Currently it has a set of late 70's heads.
 
By themselves I doubt you would feel any difference. If you were to add a 4 barrel and intake and cam, lifters, and valve springs then it adds up. Always have 302 heads magnefluxed by a good machine shop before putting a lot of money into them.
 
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Chrysler did it to millions. I guess they didn't think it was worth it.
 
By themselves I doubt you would feel any difference. If you were to add a 4 barrel and intake and cam, lifters, and valve springs then it adds up. Always have the magnefluxed by a good machine shop before putting a lot of money into them.
This^^^ Definitely want to upgrade the carb and add dual exhaust if you haven't already. If you are into it that far a 340 cam and roller timing set is definitely worth doing!
 
So, are you saying you would spend the time and money to swap "78" 318 heads for 302 heads on a stock 2 barrel 318?

Probably so, yeah. Of course, then WOULD be the time to upgrade to a 4 barrel intake and a small 4 barrel carburetor, but you will still be adding power regardless.
 
To me it would depend on the shape of the heads already on the car. If your compression checks good and pretty even across all 8 cylinders, then I would suspect you have good valves and I would leave it alone. If your needing some valve attention, I would get the "other heads" done up (including a little bowl porting) and that would speed up the car's down time.
 
thanks for the comments/feedback. I am just contemplating whether I should invest a little bit of money into the 318 and drive it for a while or just go ahead with a 5.9 magnum swap
 
invest in a little money as what? cam, 4bbl, headers, pistons...... what does a little money mean??? tell us more of what your thinking, and we can give better advice.....
 
With what you've described - no. It's not worth it. But with filling in more info like 318 asked that might change. Return on investment is very personal and individualistic. So fill us in, or consider it not worth it...lol.
 
If your planning a magnum engine swap, i wouldnt even bother taking the stock heads off your 318. Id save my money and do the magnum swap. Just my opinion.
 
A magnum swap is a long term option. Right now the car will only be a driver no track time. Current set up will be a stock intervals 318/904 with a shift kit. Excel rock intake with a edelbrock 4 barrel carb. Will have headers since I have those laying around already. 3.73 geared 8.8 rear end.
 
A magnum swap is a long term option. Right now the car will only be a driver no track time. Current set up will be a stock intervals 318/904 with a shift kit. Excel rock intake with a edelbrock 4 barrel carb. Will have headers since I have those laying around already. 3.73 geared 8.8 rear end.

Then yes, get the 302 heads, mill .020 on the block side and .019 off the intake side of the heads, good valve job, clean up the ports (see 318willruns thread on home porting or just clean the bowls up. Add a cam, lifters, valvesprings, and a double roller timing chain. Now you are talking.
 
I would not bother with the 302s unless you are adding more cam and 4bbl and either have or are going to dual exhaust

If it's otherwise stock, don't waste the time and money is my attitude.

Last time the 67 was together, I ran a 318 one summer. The block and heads were bone stock mid 70's 318. I put a small cam a bit smaller than a 340, it happened to have headers, and the low RPM version of the performer and it was amazingly snappy.
 
I think 302 are a waste, if you look at the stock hp number between non 302 headed 318's and ones with there no power difference. In general I think 318 heads are a waste unless your gonna port them but why not do a set of magnums instead. Or

Why don't you do things that will work with your future 5.9/360 swap like rear end and gears, maybe 904 with deeper first gear, exhaust and headers, ignition, electric fan and better rad, EQ heads, and air gap intake etc...
 
In my opinion, the addition of 302 heads on an otherwise stock 318 is worth the effort. Slight increase in compression, slight improvement in flow, slight improvement in performance. For an additional cost, up size valves to 1.88, 1.6. The valves themselves you might even get for free, as used take outs.

If you were to do a cam, intake, headers at some point, you could have a nice little ripper and many would not be-leave its a "Teen".

The above mods are all weekend bolt on's; begin Friday night, drive Sunday afternoon.

Good luck!
 
Chrysler did it to millions. I guess they didn't think it was worth it.
There's a difference between putting the heads on versus swapping the old heads for new. Ford also changed the bellhousing bolt pattern in the backs of 4.6s, that doesn't mean it's practical to do yourself.

Probably so, yeah. Of course, then WOULD be the time to upgrade to a 4 barrel intake and a small 4 barrel carburetor, but you will still be adding power regardless.
By themselves I doubt you would feel any difference. If you were to add a 4 barrel and intake and cam, lifters, and valve springs then it adds up. Always have 302 heads magnefluxed by a good machine shop before putting a lot of money into them.
I wouldn't. Bout the same flow, bout the same chamber size, probably lower the compression about when you change the gaskets putting them on.

All unleaded valve heads are fairly prone to cracking, from early 318 heads to TBI 360 and Magnum.

thanks for the comments/feedback. I am just contemplating whether I should invest a little bit of money into the 318 and drive it for a while or just go ahead with a 5.9 magnum swap
Just put a better motor in it. A 5.2 Magnum will be leaps and bounds ahead even.

I think 302 are a waste, if you look at the stock hp number between non 302 headed 318's and ones with there no power difference. In general I think 318 heads are a waste unless your gonna port them but why not do a set of magnums instead. Or

Why don't you do things that will work with your future 5.9/360 swap like rear end and gears, maybe 904 with deeper first gear, exhaust and headers, ignition, electric fan and better rad, EQ heads, and air gap intake etc...
Now this guy's got it. I'd take or leave any 318 head as soon as the next. If it has something that runs good on it I wouldn't invest an hour of my time doing anything to them that's not a necessity or simple. If they need seals, fix your good heads- don't pay good money for bad heads. 360s flow better and use the same rockers, Magnum (replacements) flow better and won't decrease the compression but are a better value once you're already committed to doing roller rockers and an intake anyway.

Especially when I see "driver, no track time"- I'm more curious of how the motor runs and acts now. I'd invest the money in making it a better driver than adding maybe 8hp you won't notice, possibly another 20-30 more that'll still be a good deal shy of your modest stock Magnum swap.
 
go for the 302's, u know you want to!then u will know for sure if it was the right thing to do, its definitely not the wrong thing. i was already running 302's while another set were were getting milled, bowl ported and 1.60 exhaust valves put in(some people say 1.88s arent worth it on a 318, i wish i had though,because now i'm building a 360), the new, built 302's made quite a difference over the stock ones according to the butt dyno!
 
how many of all the 302 nay-slayer's ever run a 302 head??? best head for a moderate budget minded 318 tho' it would kill some folks to ever admit it!
 
how many of all the 302 nay-slayer's ever run a 302 head??? best head for a moderate budget minded 318 tho' it would kill some folks to ever admit it!
The numbers dont lie. Best running 318's I had were 71,74. Pre 302 head.They would run with 350's easy, pull on the 2 brls.
Now who has a factory 302 head 318 that's a bad ***..?.. No body. They were low power. "120 hp" if you look it up.
If you think that head is a power adder, so are small carburetors. I have 2 pair and one odd ball. 2 are cracked...so I'm playing with them off n on now. Flowed them. They are terrible to say the least. If this is just the worst port, so be it... but how many do those numbers. All so far.
The 302 heads intake flow reflects the power.
Cfm
48
87
131
153 cfm.400 lift where they lived.
...175cfm peak intake flow over .500
120 hp...not 230 like the older teens.
675 heads flows more, and do it .100 earlier. It's the open chamber.
Just check the 318 porting for the average joe. #675 [email protected] & ...bigger .200/.300 lift numbers as cast .
302 head suffers from shrouding.
Dont get me wrong, it can be made good.
I know. But it's a ton of work work and still falls short in flow .100-.200 when comparing w/1.78 valve. I mean.. I'm pretty happy with where I've taken them so far, 215cfm but it's more work. Period.
They all can be made to hit 199cfm by .400 and 205-215 peak, the 302 needs work most wont or cant do, or have the tools to do. You need stones to do it right.
You wont gain anything other than some compression, which is what people mostly feel.. throttle response...but it wont hp/rev like it should. I spend more time trying to basically say... it's a good head... BUT.. only when modified. Know one ever looked at the flow numbers it seems like, just the 2.02 Hughes and Bj racing crap. It's lacking. Don't be chamber blinded!
 
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The numbers dont lie. Best running 318's I had were 71,74. Pre 302 head.
They would run with 350's easy, pull on the 2 bros even.
Who has a factory 302 head 318 that's a bad ***.. No body.. because they were low power. 120 hp if you look it up.
If you think that head is a power adder, so are small carburetors. I have 2 pair and one add ball, 2 are cracked. I'm playing with them off n on now. Flowed them. They are terrible to say the least. If this is just the worst port, so be it... but I've taken that port to impressive places-with a lot of work.
The 302 heads intake flow reflects the power.
Cfm
48
87
131
153 cfm.400 lift where they lived.
...175cfm peak intake flow over .500
120 hp...not 230 like the older teens.
675 heads flows more, and do it .100 earlier. It's the open chamber.
Just check the 318 porting for the average joe. #675 [email protected] & ...bigger .200/.300 lift numbers as cast .
302 head suffers from shrouding.
Dont get me wrong, it can be made good.
I know. But it's a ton of work work and still falls short in flow .100-.200 when comparing w/1.78 valve.
They all can be made to hit 199cfm by .400 and 205-215 peak, the 302 needs work most wont or cant do, or have the tools to do. You need stones to do it right.
You wont gain anything other than some compression, which is what people mostly feel.. throttle response...but it wont hp/rev like it should.

I spend more time trying to basically say... it's a good head... BUT.. only when modified. Know one ever looked at the flow numbers it seems like, just the 2.02 Hughes and Bj racing crap. It's lacking. Don't be chamber blinded!
'ats why i said moderate budget not badass! with work and or money thay can be better but by then it makes better sence to afford a better head,..but then ya might as well afford a bigger block....and then afford a bigger crank,...its a slippery slope!!
 
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