351 heads on a 302?

Jul 26, 2021
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Question I just picked up a great 302 short block, I am currently running a Windsor in our 67, I remenber when we were younger I always herd of guys putting Windsor heads on a 302 ,, any feed back would be appreciated, thanks
 
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351w heads are a pretty old-school head upgrade at this point. Put simply...there are a ton of better options available these days. Used aluminum heads are fairly cheap these days....so are GT40-P Explorer heads...both give you better power than 351w heads. The only reason to use 351w heads is if they are free and you aren't looking for a lot of power, just a small bump.
 
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Cost roughly ten thousand but I put 4V Boss 351C heads on my first one. Takes a boss 302 manifold and freeze plugs installed in the head deck surface then drill coolant holes in the intake surface. Mine makes about 420 pups and passes IM for 1980 with Hooker super comps and a Dura Spark II ignition system holley 780 on a Gapp and Roush intake. Nostalgia only as you can do much better than that with the new aluminum heads GT 40 in particular
 
Iron heads do have their advantages for sure...much more resistant to blowing head gaskets and to staying straight when they do...but even so, you have better iron head options than old 351W heads anyway....GT40P heads from an explorer are dirt cheap and iron, flow well from the factory and better if you do a bit of work to them.

Personally for a SBF I always wanted to swap on some LS1 heads and run a custom cam to correct the firing order. More because building cross-make frankenstein engines is fun for me...similar to my 2.3L Ford block and Volvo head engine...not that it is any way efficient or a good use of time and/or money.
 
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Stock 351w heads on a 302 will be basically a wash. Slightly better flow offset by larger chambers and lower compression. Bill Carrolls Ford Stockers Bible says this very thing about the swap. They have to be ported to be worth a darn. I have '70 351w heads on a 331. They were ported extensively by myself and the engine makes 360 RWHP or around 430 FWHP @ 6500 (obviously other mods besides heads were done to obtain these results). Stock, the ports are something like 140cc intake and 50cc exhaust. After porting they were 160cc intake and 60cc exhaust. Heads are probably flowing in the 230 and 175 cfm range for intake and exhaust, respectively. Just putting a set of stock 351w heads on a 289 or 302 will do very little to nothing.
 
Iron heads do have their advantages for sure...much more resistant to blowing head gaskets and to staying straight when they do...but even so, you have better iron head options than old 351W heads anyway....GT40P heads from an explorer are dirt cheap and iron, flow well from the factory and better if you do a bit of work to them.

Personally for a SBF I always wanted to swap on some LS1 heads and run a custom cam to correct the firing order. More because building cross-make frankenstein engines is fun for me...similar to my 2.3L Ford block and Volvo head engine...not that it is any way efficient or a good use of time and/or money.
What do you mean “correct the firing order”? Which order is incorrect, the standard Ford, the HO order, or both? And how would help.
 
What do you mean “correct the firing order”? Which order is incorrect, the standard Ford, the HO order, or both? And how would help.

That was in regards to running LS-series heads on a Ford block, it requires a custom cam because of the difference between LS and SBF firing orders...or so I have heard, one of those things I know is possible and have read a couple articles about but don't have the in-depth knowledge to attempt yet myself(lord knows I have enough other projects without frankensteining together a SBF block and LS1 heads)
 
The heads do not care what the firing order is in. The crank, intake and NHV might. The firing order has to match the crank and camshaft(s).
The Ford HO firing order switched two cylinders, and it matched the standard Chevy firing order.
But before we get into if the cylinders are numbered the same so you can see how the LS and HO compare, I have to wonder - why do this?
By the time the modifications are made to the block, (if it is even the same bore spacing), that will be a lot of money making great heads fit a much weaker block. It is stupefying how much power @LaserSVT puts through an ls block in a Vette. I doubt a 351 block would stand that level of boosted power for more than two trips to the store. Heresy alert - it would be better to swap an entire LS long block engine in.
Now if someone were to apply as much of the LS head’s design into Windsor compatible castings, I would strongly consider them and a stronger block.

 
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The heads do not care what the firing order is in. The crank, intake and NHV might. The firing order has to match the crank and camshaft(s).
The Ford HO firing order switched two cylinders, and it matched the standard Chevy firing order.
But before we get into if the cylinders are numbered the same so you can see how the LS and HO compare, I have to wonder - why do this?
By the time the modifications are made to the block, (if it is even the same bore spacing), that will be a lot of money making great heads fit a much weaker block. It is stupefying how much power @LaserSVT puts through an ls block in a Vette. I doubt a 351 block would stand that level of boosted power for more than two trips to the store. Heresy alert - it would be better to swap an entire LS long block engine in.
Now if someone were to apply as much of the LS head’s design into Windsor compatible castings, I would strongly consider them and a stronger block.

Yeah but my long blocks built for 2000HP and I am only using 3/4 of it. Granted its just an off the shelf GM 6.0 LQ iron block bored and stroked but even the little aluminum LS1 can do 1000. Really wanna piss someone off you go spend $600 on a JY 5.3 then spend another $600 in forged pistons and new rings, $1200 for an ebay turbo kit and you now have a motor that makes 1000hp all day long without even changing the cam LOL
oddly GMs weakest LS engine was the one that made the most power stock. Damn LS7s seem to fall apart at 4 digits.

I love my Fords, owned way too many to count but the LS/LQ engines are a marvel for how cheap and simple they are.
 
Yeah but my long blocks built for 2000HP and I am only using 3/4 of it. Granted its just an off the shelf GM 6.0 LQ iron block bored and stroked but even the little aluminum LS1 can do 1000. Really wanna piss someone off you go spend $600 on a JY 5.3 then spend another $600 in forged pistons and new rings, $1200 for an ebay turbo kit and you now have a motor that makes 1000hp all day long without even changing the cam LOL
oddly GMs weakest LS engine was the one that made the most power stock. Damn LS7s seem to fall apart at 4 digits.

I love my Fords, owned way too many to count but the LS/LQ engines are a marvel for how cheap and simple they are.

I have one of those weakest link LS7s in a 2013 Corvette 427 Convertible. At 40K miles the oil pressure dropped about 10 lbs. One day months later, the oil pressure dropped a bunch more. Took it to the dealer and the engine was toast. The rod side clearance had grown to .080 due to the titanium rod coating wearing off and the titanium rods eating up each other. Titanium is strong and light, but it galls when it is continuously rubbing against other surfaces, thus the nitride coating on the rods. Anyhow, I got a new engine and new dry sump oil system for $100. I had a full coverage extended warranty. The actual cost was $24K. This problem is one of the most common LS7 failure points.

I think Chevy made a mistake by using titanium rods in the LS7. I don't think they needed to go to titanium to be able to have a 7000 rpm redline. The piston in an LS7 has a real short deck height and is lightweight. A good steel rod would have worked and would have been more reliable over the long run. Heck, use steel rods and lower the redline to 6500 if that is what it would have taken. Peak HP is around 6100 as I recall.
 
I agree. Mine spins to 7700 with the TFS heads..... not sure what kind of valves they use but they did a 5 angle valve job on mine.
 
The heads do not care what the firing order is in. The crank, intake and NHV might. The firing order has to match the crank and camshaft(s).
The Ford HO firing order switched two cylinders, and it matched the standard Chevy firing order.
But before we get into if the cylinders are numbered the same so you can see how the LS and HO compare, I have to wonder - why do this?
By the time the modifications are made to the block, (if it is even the same bore spacing), that will be a lot of money making great heads fit a much weaker block. It is stupefying how much power @LaserSVT puts through an ls block in a Vette. I doubt a 351 block would stand that level of boosted power for more than two trips to the store. Heresy alert - it would be better to swap an entire LS long block engine in.
Now if someone were to apply as much of the LS head’s design into Windsor compatible castings, I would strongly consider them and a stronger block.

Well, the reasoning behind doing the head swap is its dirt cheap and fun....you can find any number of LS heads for $100 a pair that someone is upgrading to later LS-series heads. As to whether its easier to just swap an entire LS engine of whatever type...absolutely, but where is the fun in doing things the easy way? I enjoy the Folvo 2.3T engine I built because the project itself was fun...not because the end result is any better than a turbo Duratec 2.3L(certainly not from a weight perspective), So yep, I would be much more likely to build a hybrid engine than to just use an LS engine
 
Well, the reasoning behind doing the head swap is its dirt cheap and fun....you can find any number of LS heads for $100 a pair that someone is upgrading to later LS-series heads. As to whether its easier to just swap an entire LS engine of whatever type...absolutely, but where is the fun in doing things the easy way? I enjoy the Folvo 2.3T engine I built because the project itself was fun...not because the end result is any better than a turbo Duratec 2.3L(certainly not from a weight perspective), So yep, I would be much more likely to build a hybrid engine than to just use an LS engine
The used heads might be cheap. Please keep a running total and let us know how much it costs to get it together and running.!
 
I skimmed thru this thread but..
The SBF HO firing order and the LS firing order are the same, the only difference is what cylinder is fired first...
I often grab LS wiring harnesses and repin them for SBF engines when I do coil conversions.
 
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I skimmed thru this thread but..
The SBF HO firing order and the LS firing order are the same, the only difference is what cylinder is fired first...
I often grab LS wiring harnesses and repin them for SBF engines when I do coil conversions.

Maybe LS heads would be a near bolt-on then? Aside from whatever intake manifold nonsense you have to pull anyway. Heh, now I might be forced to play with the idea sooner than I intended...I do after all have a Miata without a drivetrain waiting in my garage until I finish the Mustang.....seems a good platform for a bastardized engine.
 
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