Ported 351W heads vs. Aftermarket

[pdw5000]

I had wrote in a previous thread that I was building a 10 sec 68 mustang and that my engine builder is using stock 1971 351W heads and is polishing and porting them. He is increasing the valve size I assume (I don't know the specifics). Some of you spoke of some concern that it is not possible to make this kind of power with a 408 stroker with ported windsor heads. My engine builder swears that he can flow test them against aftermarket heads and it will do just as good and he thinks the ported heads will give me better throttle response. I was working with a budget but I think the builder wants to do this because the money for the porting goes to him for labor vs. just buying the aftermarket heads and not making any money on it. So my question is can a stock 351W head properly ported make the same amount of power as an aftermarket head...say Trick Flow Wedge, Edelbrock Victor Jr. etc....

The builder is very reputable in my area and builds all performance Ford engines. He builds Limited Late Model dirt track engines all the time and he currently has built all the engines in the cars that have won in the past 3 years. He believes the setup I am running will make more power than a limited late model car (535hp) because you are allowed to stroke the engine to a 408 vs 358 for a limited late. All the other parts are basically the same in both engines. I'm not a limited late model car guru though.

Please help. He is porting the heads now!

 

[classic boost]

So my question is can a stock 351W head properly ported make the same amount of power as an aftermarket head...say Trick Flow Wedge, Edelbrock Victor Jr. etc....

absolutely not- esp the vic jrs. with labor, new valves, springs, ect, you'll have more in those heads than an aftermarket one.
throttle response will not be a problem with a 408.
you'll be lucky to get 450fwhp out of the stock ported ones.

 

[Decurion]

In stock form, the 351w heads can make about 350hp from what Ive seen (thats on a 302, maybe a little more on a bigger engine). Im sure porting will make a big difference, but 200 horsepower? I dont think so, but thats just my opinion.

 

[SadbutTrue]

Rusty67 is getting Thumper to pocket port some 351w heads (i think... might be 302 heads). With bigger valves and extensive porting they swear that they'll make power comparable to aluminums.

That said, you can get nice aluminum heads capable of supporting 500 horsepower or more on ebay for that much, which haven't been touched and weigh half as much.

I'd just go aftermarket, especially with all the money you're talking about spending on the rest of the car it'd be foolish to not go all out on the heads.

 

[Sicarius428]

I would go with some aftermarket AL heads. Out of the box they will flow great without any work. A little touchup and they will flow even better and it is a lot easier and less time consuming to port AL. Another thing to consider is that the AL heads will save you 50 lbs off the front of the car and you can run a tad more timing. I am not doubting your builder's porting capability but I would put my money on something designed by a computer rather than working over some 40 year old technology.
A link.
http://airflowresearch.com/articles/article046/A-P1.htm
http://airflowresearch.com/articles/article112/A-P1.htm
Kevin

 

[rbohm]

ported stock heads can possibly out flow out of the box aftermarket heads, but not by much. the potential of even the smallest of the aftermarket heads can out flow anything the factory put out even in modified form. go with a good set of aftermarket heads.

 

[Hack]

Unless you are absolutely set on having a completely stock external look to the engine, it doesn't make sense to have the factory iron Windsor heads ported. Aluminum heads are a better investment. They are cheaper for additional porting if you ever want, they are easier to repair, lighter, and you can run more compression without detonation.

 

[57fairlane]

I would think max-effort D0OE/gt40 heads could support 350-360 to the tires with that big of a motor and a custom-ground cam.

My home ported e7s made right at 308rwhp on a 347 with stock valvetrain if that is any idea how bad production iron heads are vs. a aftermarket aluminum head

 

[pdw5000]

The builder is swapping me my old 302 engine for a 351W and I'm giving him 6k to build it. He claims it will make enough power to run me in the 10s if I can get it to hook. He claims by using the stock heads and porting them that he can do it for that money. I just gave him the money and he selected the parts. I'm just questioning his desicion to use the stock heads over aftermarket which I'm sure you all agree. I think he did this because he can save money on parts and get the rest of the money in labor. The price includes all forged internals too. I don't think thats a bad price since he is guarenteing it. Like I said he is very well known in my area and I have seen some of his engines run very well so maybe he knowns something.

 

[SadbutTrue]

The builder is swapping me my old 302 engine for a 351W and I'm giving him 6k to build it. He claims it will make enough power to run me in the 10s if I can get it to hook. He claims by using the stock heads and porting them that he can do it for that money. I just gave him the money and he selected the parts. I'm just questioning his desicion to use the stock heads over aftermarket which I'm sure you all agree. I think he did this because he can save money on parts and get the rest of the money in labor. The price includes all forged internals too. I don't think thats a bad price since he is guarenteing it. Like I said he is very well known in my area and I have seen some of his engines run very well so maybe he knowns something.

I don't doubt that a completely worked, every trick pulled, set of 351w heads could put up some decent #'s, and some people swear by them.

 

[pdw5000]

So I called AFR to see what they thought about this and I talked to Steve and he said that they have compared some "good" ported stock 351W heads and they have been able to compete with most aftermarket heads. He said that a professional, not a garage-do-yourself type port job can flow the same or even outflow a World Windsor Sr., Twisted Wedge, Victor Jr. etc. Although they won't be able to compete with race series heads like the AFR 205 and 225. The main way that a good port job could compete with these type of heads according to AFR is because if you know what you are doing you can use smaller runners with a good design to flow air more smoothly and faster. Smaller runners gives you higher velocity flow and better throttle response if you reshape the port correctly. Of course you have upsize the valves and all that good stuff too.

I was surprised by this but I told them my story and they believed that my engine builder may be capable of doing it. I think we all know that AFR knows their stuff when it comes to heads. I wish I had some spare money and I would have just got AFR's from the start and then there would be no worries!

 

[Sicarius428]

For 6k, I would say that is pretty fair. A new set of heads will run you close to 1500 and his port work will probably cost you 600ish. This is all depended if it meets your HP goals but we will just have to see. This issue is often seen on fordfe.com. A lot of people spend 800 bucks on a great port job but that is getting close to aftermarket aluminium heads which will flow about the same out of the box. If you will be satisfied with the HP level of the car stick with the cast but if you are going for 10s, you may not be able to obtain it because of suspension, driving and what not... to the point. If you are lacking power, aluminium heads will give you that potential to port them later if needed. Some worked over cast heads are not and if you try to sell them won't return you much of an investment if you see fit to upgrade later.
Kevin

 

[418mach]

I would have suggested that you got a parts build list before you parted with your money there are a few more things to consider other than the heads. For my motor i wanted a boss type motor in choosing to go with aftermarket CHI's that were going to be a little more expensive than a full professional job done to the max on a pair of 2V cast iron heads was offset by the CHI heads out of the box were already there with heaps more potential, redesigned runners, run cooler and more efficient, run higher comp etc. I see on most forums i visit guys building windsor strokers with windsor heads for street are looking for 500FWHP with good parts. The only part used out my donor motor was the block, for 600+ every other piece was replaced new including everything from the harmonic balancer to wheels. The point i am trying to make is within your budget the strength and quality of the parts have to match the potential of the motor.

 

[57fairlane]

10s with D0OE heads . . .

not that it can't be done but wow . . . it would be much easier with aftermarket heads at that point.

You will probably have to have a light car, have it hook up, and drive it well.

 

[classic boost]

sorry, bit if you even run 11's, i'll eat my hat.

 

[blown65]

Don't forget the weight you take off the front of the car going to a nice set of Alum heads.

Our 408 in the Pantera runs AFR 205 and runs very strong. With all the plans you have been listing, Id put something else on hold and go with the 205 or 225's depending on what the rest of your build is. The Pantera has zero issues with weight transfer since the engine is in the rear, and those big 13" wide G-Force tires still cant hold the power it makes.