Replacing 302 heads with magnum heads

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The amount of work they put into those heads would cost you as much as a new set of EQs completely assembled. If you've never ported iron heads before, it's a good bit of work just cleaning up the bowls. They ported stock 318 castings to 360 port window size, did a good bit of bowl work after cutting the seats out and using a bowl hogger...there's a LOT of work in those 302s.
 
Sliding in a new bumpstick would be a good way to take better advantage of the better ports. The 270 magnum grind is indeed a good one...I used in a Ford 306 before with decent heads and it didn't stop pulling till about 6200...
 
Opinions will be everywhere, but when it comes down to it, the amount of effort you'd put into the 302s would be costly to mimic the effects they got with junkyard jewel, and the people who built that engine (Freiburger, Dulcich, and Brule for the dyno tuning) have literally decades of experience tweaking engines on the dyno to make max power, and many times they're difficult to duplicate.

Take a read through the rest of these forums and see what others think of tossing magnum heads on their 318s compared to whatever their engine came with so you have a bigger sampling...
 
Use the magnums with the cam you have. .441 lift of your current cam is based on 1.5 rocker. The stock 1.6 Magnum rocker will give you .470 lift and speed up the valve opening and closing rate. 3.55 gear and good converter or 4 speed and your A body should break the tires loose at will.
 
next time anybody mentions a comp 268 I am going to puke. Better yet, make it a drinking game an every time somebody mentions a Comp 268 cam, everybody takes a shot. Use the Magnum heads, get new head bolts, a new cam and some pushrods. The Magnums heads flow better than 302 heads do ported which will cost as much as EQ's. Ie you might be able to port 302's to flow better than stock magnums but not for the price of new EQ's and they will flow enough to satisfy any cam you will want to use on the street.
 
:rofl:

If I didn't know any better, I'd say you don't like that grind much or feel that too many people use/recommend it
 
I'm watching this thread closely because I have a set of magnum heads that I will most definitely be putting on my 318. I have small valve J heads now, and while the flow at high rpm is great I'm looking to add compression on the cheap. The magnum head lets me keep the flow and add compression. Again, on the cheap.
 
Bolt pattern is the same, ports are certainly no bigger. I haven't personally had a need to, but I don't see why they wouldn't.
 
Why not just grab the whole 318 magnum??? excellent running magnums with a little over 100k miles can be had between 300-375 bucks. Then you get the roller cam for todays oils. put your LA front (timing cover and such), need a intake and oil pan/pickup. You can even use a cam from a 89-91 360 to get the snout for the mechanical fuel pump. I wouldn't even rebuild it, put it in as is. I bet you can buy a 318/360 mag and get it ready to install for 750.00 (or less). These 318 mags have better flowing heads, better compression, roller cams, and with a roller LA cam, they have more lift, and a lighter rotating assembly. Very cheap performance, and these motors run to 300k miles without batting an eye, so I wouldn't be afraid to buy a good runner with 150k miles. Just a thought........
 
Indeed.

Otherwise, I'd agree with 318--the 5.2 in my Scamp was free to me until I had to replace the crank and bearings. Between the cost of bearings and the local machine shops charges for grinding/polishing, it was actually cheaper to buy a crank kit. I mistakenly did the hughes cam extender as opposed to an LA roller cam...dumb dumb dumb.
 
txstang84 said:
:rofl:

If I didn't know any better, I'd say you don't like that grind much or feel that too many people use/recommend it
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Crappiest cam grind ever and I will never understand why people are so in love with it. Thing was designed in 70's to work with marginal LA heads, not modern high quench chamber designs of todays engines. Its like recommending McDonalds as a great restaurant....it might "qualify" as food but its not. Anybody running a 268 is leaving power unused, unless they are still running mid 70's smog heads.

CRAMAR said:
My Question is will 340 H.P. manifolds work with Magnum Heads?
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there is about 1/8" of port not covered using them, much like putting them on a 318.

gasket leak.jpg
 
^^ good info-I guess the hedman tight tuck LA pattern headers have a slightly bigger footprint

I'm still chuckling about the cam hatred...FWIW, it was designed for stock induction/exhaust SBCs...not LAs...they took the lobe profile and ground it on all their other cores...look it up, the lobe profiles are the same for duration at .006/.050, lift, ICL, and LSA as 268Hs for any other domestic V8
 
The 340 exhaust manifolds do fit but I had to double gasket them to get them to seal. The magnums are more expensive in that you either have to order them with the la intake pattern or get a Eddie intake. Yoe also need to get the correct pushrods, lifters and I had the studs replaced with 7/16ths ones so I can run any spring pressure I want. You'll need around 120#s on the seat and 320 #s on the open valve if you use a roller cam. Mine are good for .510" lift and have some bowl work. They flow better then most la heads. Mine came in at 68cc's out of the box. You'll have to hunt for a source for the 62cc's. The question is, do you really need to use them on your build, the 302's with some work will do fine and you'll save a lot of work and money. One other thing, I'd get a custom grind cam, maybe send them a good core and tell them what your plans are. Good luck, the 318 is a great motor built right.
 
This is the combo it seems everyone hates but 318 30 over, XE268 cam, performer intake, reman 302 heads and KB 167 pistons. Has as much power as 360 magnum but less street-able. IMO 302 heads are great on a 318 LA.
 
txstang84 said:
^^ good info-I guess the hedman tight tuck LA pattern headers have a slightly bigger footprint

I'm still chuckling about the cam hatred...FWIW, it was designed for stock induction/exhaust SBCs...not LAs...they took the lobe profile and ground it on all their other cores...look it up, the lobe profiles are the same for duration at .006/.050, lift, ICL, and LSA as 268Hs for any other domestic V8
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Most cams were Chebby cams just ground on different blank...thats why we work with Racer Brown to design all our cams, specifically magnum rollers...and we get tons of **** because we dont follow the big guys outdated ideas. We also dont make lumpy cams that dont make good power, if you want it to sound like a top fuel car with a [email protected], get a CD of John Force idling and play it over the stereo super loud rather than put a choppy sounding low power cam just so you can feel cool in the store parking lot. I have the same feelings about those cams as I do about coffee can exhaust on a 100 hp ricer.
 
True story and fair enough. I'm not giving you any hell, I just thought the response was perhaps a bit...hyperbolic...but entertaining nonetheless.
 
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