Hello all, looking for 351 build help.

[pablo63 10]

I stumbled upon this site while looking for info on building a 351. I was hoping someone in here might help me instead of discourage me. I have this idea to build a nice solid dependable 351 that will put down between 350-400 hp/tq at the flywheel. This is pretty easy to do with all the aftermarket performance parts out there but here's the rub. I want to do it with stock heads, rods and probably crank.

I belong to a couple forums where there are alot of guys who have big money. They buy whatever they need for hp but never work for any of it. They tell me to stop being cheap or stop wasting my time. Buy this head or that kit, BLAH BLAH BLAH. They have to have 5,6,700 HP and most are probably afraid to drive their cars. They don't understand I'd rather have a car that is not overpowered and is a solid driver that can go all day long without overheating.

So if any of you guys know anything about building a 351 that will do what I want please give me some advice. Here's what I have so far. A D4 351 Block, D5AE heads that I'd like some info on porting, a stock crank and rods, performer intake, pertronix billet distributor, new eddy waterpump and comp double roller timing set. I also have a cast 3.85 crank, possible 393? What cam and pistons would work good with what I have in mind? Carb? Thanks in advance I hope someone here can give me some ideas.

[pablo63 10]

I stumbled upon this site while looking for info on building a 351. I was hoping someone in here might help me instead of discourage me. I have this idea to build a nice solid dependable 351 that will put down between 350-400 hp/tq at the flywheel. This is pretty easy to do with all the aftermarket performance parts out there but here's the rub. I want to do it with stock heads, rods and probably crank.

I belong to a couple forums where there are alot of guys who have big money. They buy whatever they need for hp but never work for any of it. They tell me to stop being cheap or stop wasting my time. Buy this head or that kit, BLAH BLAH BLAH. They have to have 5,6,700 HP and most are probably afraid to drive their cars. They don't understand I'd rather have a car that is not overpowered and is a solid driver that can go all day long without overheating.

So if any of you guys know anything about building a 351 that will do what I want please give me some advice. Here's what I have so far. A D4 351 Block, D5AE heads that I'd like some info on porting, a stock crank and rods, performer intake, pertronix billet distributor, new eddy waterpump and comp double roller timing set. I also have a cast 3.85 crank, possible 393? What cam and pistons would work good with what I have in mind? Carb? Thanks in advance I hope someone here can give me some ideas.

[69gmachine 15]

Welcome pablo.

 

The stock crank and rods can easily handle 350 to 400 HP, although if you can find a set of truck rods they are better because they have spot faced rod bolts rather than broached.

 

If you're just bent on stock heads, you can achieve 350, probably even 400 HP with the right cam, intake carb and headers. However, the D5 heads have ports sized for a smog era 150 HP 302 and open chambers with no quench. You will need the D0 castings that were produced through 1974. You will need to open up the exhaust ports and remove the thermactor bump, and port match the intake ports. You will also need to have them milled and tapped for screw in rocker studs so you can run a healthy cam, and should plan on replacing the valves and guides. So expect to have a grand in them by the time they're ready to bolt on.

 

The amount of labor and parts needed to make a decent set of stock heads is what drives most people to buy new heads that are ready right out of the box. If you can find a used set that has already been worked on, then that may be your best bet. Power heads sells reworked stock E7 castings

[69gmachine 15]

Welcome pablo.

 

The stock crank and rods can easily handle 350 to 400 HP, although if you can find a set of truck rods they are better because they have spot faced rod bolts rather than broached.

 

If you're just bent on stock heads, you can achieve 350, probably even 400 HP with the right cam, intake carb and headers. However, the D5 heads have ports sized for a smog era 150 HP 302 and open chambers with no quench. You will need the D0 castings that were produced through 1974. You will need to open up the exhaust ports and remove the thermactor bump, and port match the intake ports. You will also need to have them milled and tapped for screw in rocker studs so you can run a healthy cam, and should plan on replacing the valves and guides. So expect to have a grand in them by the time they're ready to bolt on.

 

The amount of labor and parts needed to make a decent set of stock heads is what drives most people to buy new heads that are ready right out of the box. If you can find a used set that has already been worked on, then that may be your best bet. Power heads sells reworked stock E7 castings

[Max Power 74]

You will spend just as much money on those doorstop heads getting them to 400hp as you will in getting a decent set of aftermarkets. Why restrict yourself? It's old technology. That's like saying I want to build an autocross car but want to stick to drum brakes.

 

The 385 crank would be a 393 most likely, and I believe you can use stock rods and 302 slugs to get there. I built a 393 for about 3 grand that way.

[bigperm2 10]

Unfortunatley, you are starting out with probably the worst production heads. That will be what prevents you from reaching the 351-400 HP level. Even if you put a big cam, lots of compression, free flow everything else, the heads are a flow bottleneck, I just kinda doubt it can get there easily. I had a post a while ago about installing GT40P heads on my 351, which is what I have done. With stock exhaut manifolds and 8.5ish:1 compression, I am thinking I am shy of 275HP. Add headers and good compression, and the right cam, I think it would be closer to 350HP. I can't comment about how it runs because the car is a year away from being road worthy. I did build a budget 302 for a 66 f100. This truck has a stock explorer motor with gt40p heads, 9:1 compression, headers, and a trick flow roller cam. I haven't had the motor dynoed, but the seat of the pants dyno says it is pretty quick. Hot rod magazine did a "junkyard jewel" article a while ago, with a 351 and GT40P heads, and got nearly 400HP. the last set of GT40P heads I got cost me $30 on half price day at the local u-pull junkyard. With 140k miles, the seats and guides were good, I just added new seals and did a mild port job. I am a big fan of these heads, and think it is the way to go to get the power you want.

[pablo63 10]

Welcome pablo.

 

The stock crank and rods can easily handle 350 to 400 HP, although if you can find a set of truck rods they are better because they have spot faced rod bolts rather than broached.

 

If you're just bent on stock heads, you can achieve 350, probably even 400 HP with the right cam, intake carb and headers. However, the D5 heads have ports sized for a smog era 150 HP 302 and open chambers with no quench. You will need the D0 castings that were produced through 1974. You will need to open up the exhaust ports and remove the thermactor bump, and port match the intake ports. You will also need to have them milled and tapped for screw in rocker studs so you can run a healthy cam, and should plan on replacing the valves and guides. So expect to have a grand in them by the time they're ready to bolt on.

 

The amount of labor and parts needed to make a decent set of stock heads is what drives most people to buy new heads that are ready right out of the box. If you can find a used set that has already been worked on, then that may be your best bet. Power heads sells reworked stock E7 castings

 

I've researched the heads and these are the last of the DO type castings. Larger valves, ports and unfortunately thermactactor bumps as well. The chambers are 62-64cc? so not nearly as bad as the later heads. They have the stud rockers as well so no machining there. I'm going to get started on one intake and see how it goes. If I can get 200 cfm do you guys think I can wring 400hp/tq out of her?

[6T9Mach1 12]

The stock rods and crank are not a problem. You will want to install ARP rod bolts in the stock rods and get the entire rotating assembly balanced.

 

The stock heads are going to be more of a problem. To reach the hp goals you are setting with stock heads you will need a cam that will require you to use screw in rocker arm studs and you will also need upgraded valve springs. This along with getting the heads rebuilt will cost you almost as much as a set of aftermarket heads. In my opinion, its better to use a set of aftermarket heads. Used heads many times will cost you about as much as a new set of heads to get the setup properly. Heads are were the power is made; dont cheap out on the build with the heads. That is the wrong place to cut money.

 

A 351w, .030" over, 10.5:1 compression, Trick Flow 170cc twisted wedge heads, Comp cams xtreme energy XE272 cam, Weiand Stealth intake, Holley 750HP carb, long tube headers, will get you to the 400hp mark easily.

[MrD2 10]

A more free flowing exhaust, headers, and electric fan on radiator gains relatively cheap horsepower. Take the original fan off and this will free up around 15-20 hp. You may want to pull intake air from outside the engine compartment. MrD2

[pablo63 10]

Heads are were the power is made; dont cheap out on the build with the heads. That is the wrong place to cut money.

 

A 351w, .030" over, 10.5:1 compression, Trick Flow 170cc twisted wedge heads, Comp cams xtreme energy XE272 cam, Weiand Stealth intake, Holley 750HP carb, long tube headers, will get you to the 400hp mark easily.

 

 

Not about cheaping out. More of a challenge really. I want to see what can be gotten out of an old set of heads that's all. I found a guy on another site who made 450HP with ported D5's, roller cam, 9.5 to 1 cr, stock bottom end and a Vic JR. so I'm feeling pretty confident I can come pretty close to that. He's supposed to send me some pics and tips. In the mean time I started porting the exhaust ports. Knocked down one of the Thermactor humps. About twenty minutes to get the bulk of it gone.

[Max Power 74]

Not about cheaping out. More of a challenge really. I want to see what can be gotten out of an old set of heads that's all. I found a guy on another site who made 450HP with ported D5's, roller cam, 9.5 to 1 cr, stock bottom end and a Vic JR. so I'm feeling pretty confident I can come pretty close to that. He's supposed to send me some pics and tips. In the mean time I started porting the exhaust ports. Knocked down one of the Thermactor humps. About twenty minutes to get the bulk of it gone.

 

 

Seems like you are pretty convinced you want to use the factory heads, even though every response has suggested otherwise. I would guess your mind was made up before you asked the question.

 

I would like to see your dyno results after the build is done. It would be very cool if you could get the power numbers you are looking for with those heads. Keep track of the costs so we can compare what you did vs aftermarket heads. I would like to see the result.

[6T9Mach1 12]

Its not cheap to make power with stock heads unless you know how to port heads which very few people really know how to do. You can make power with worked over stock heads; its been done. There is a guy over on VMF that made 430hp with worked over stock heads and intake with a big OTS comp cams flat tappet camshaft. Thing looks bone stock. Its just going to take some coin

[pablo63 10]

Seems like you are pretty convinced you want to use the factory heads, even though every response has suggested otherwise. I would guess your mind was made up before you asked the question.

 

I would like to see your dyno results after the build is done. It would be very cool if you could get the power numbers you are looking for with those heads. Keep track of the costs so we can compare what you did vs aftermarket heads. I would like to see the result.

 

 

Yeah my made was made up as far as wanting to use stock iron. I was looking for porting ideas or maybe a link someone could direct me to that gave some tips or how too's. This 351 is not a priority right now so it will be a while before I get her on a dyno. Figured I'd just tinker on the porting this Winter and get a little more serious come Spring. I guess the thing to do would be see what I end up with for flow before I pick the rest of my parts. Still need to drop the block off for the full treatment also. I'll be sure and take some pics along the way and keep track of the money involved.

[pablo63 10]

Its not cheap to make power with stock heads unless you know how to port heads which very few people really know how to do. You can make power with worked over stock heads; its been done. There is a guy over on VMF that made 430hp with worked over stock heads and intake with a big OTS comp cams flat tappet camshaft. Thing looks bone stock. Its just going to take some coin

 

May have to take a look over there and see if I can track him down.

[RPM 1,190]

super nice ride Max, color turned out beautiful!

[Max Power 74]

super nice ride Max, color turned out beautiful!

 

Thank you Sir!

[ammosteve 10]

Using the stock iron heads will require a rather large cam to reach your power goals and drivability will suffer. Those D5 heads are terrible...they were worthless even on 302s. A more appropriate size head will reach your power goal with a much smaller cam and great drivability. If you are dead set on running iron heads the early GT40 would be a ton better than the D5s...If you don't mind an aftermarket iron head a Windsor Sr would work.

 

Steve

[bigperm2 10]

I do appreciate the challenge that you are putting yourself against. There was an article in car craft a while ago (nov. 07???) where they did a "budget build" on a junkyard 302, using a non-roller block, stock heads and a summit racing budget cam. I can't find the article to see what they did with the heads, but they made 279hp and 300 ft-lbs torque. So it will be a fun challenge, and I believe it can be met. A flow bench, and compression ratio with a bigger cam will be your friend for this build.

[Max Power 74]

Agree that it is a challenge, but I kinda look at it a little differently. For years Chevy small blocks owned Fords, and the reason they did is because Chevy made a much better flowing head from the factory. Windsor based Fords only began to compete on equal grounds with the Chevy once aftermarket heads came out. Until then they got smoked.

 

Why someone would go back and try to incorporate the one thing that held Ford back for 30 years is beyond me. If the technology is there, especially affordably, why not use it? It's like insisting on using drum brakes for autocrossing or using pay phones instead of a cell.

 

I applaud the effort, but it is a path I would never take.

[6T9Mach1 12]

Now if we were talking about a Clevor engine with Cleveland heads that would be a different conversation. If you are looking for a challenge, a Clevor build is challenging. Cleveland heads, solid flat tappet camshaft, Holley double pumper...old school :rockon:

[pablo63 10]

Just curious, is a Clevor build any wider or taller than a Windsor?

[69gmachine 15]

Yes, both, but not enough to really matter. Get a set of Aussie 2Vs and you can have a killer 392. You won't need to do any porting.

[6T9Mach1 12]

Clevor builds are not an easy thing to do so if you plan on doing the work yourself and do not have much experience building an engine it is probably not the best choice. Not saying that it cant be done there is just a lot of work involved. Clevors just have a cool factor, and I'd thought I'd mention it since Cleveland heads are one of the best factory heads made by any company and they are stock iron which is what you are looking for.

 

Personally, I'd run a set of 4v heads with a custom camshaft to take advantage of the ports and valves of the 4v heads. Yes 4v heads have huge ports and huge valves which can be a problem on the street with the wrong camshaft and gearing but if you run a custom camshaft I would not worry about it. If you plan on running an off the shelf camshaft then the Aussie 2v heads are probably best. Dont be scared off by custom camshaft; they are the only way to fly in my opinion. Its worth the extry $100 to get the right camshaft the first time around and the increased driveability and efficiency that they offer. Could be one wicked engine.

[stangme428 33]

yup... i would do the aussie 2V's ... i did AFD aluminum cleveland heads on my stroked 408... but i went way over budget...500+hp/500+tq.. had head problems and spent money to fix it... and have a lot of compression due to the wrong piston/rod combo. live and learn, ill do a different piston/rod combo in a year or so.

 

building a 392 with the aussie 2V should be a good combination. i think ausfordparts dot com has them.. but plan on doing research so you can tell the machine shop the mods you want. also, figure out what cam/springs and valves you want/need, rocker arm length changes, requires new pistons and measure for new push rods. flight96 built a clevor with factory 2V cleveland heads on his 351W.

 

if you want something different ... this is it...

 

 

Yes, both, but not enough to really matter. Get a set of Aussie 2Vs and you can have a killer 392. You won't need to do any porting.

[pablo63 10]

Clevors are a pretty cool beast but not what I'm looking to do. I think space will be a problem for me as it is. I have been working on porting these D5's and hope to finish one set of ports in the next couple weeks. Then I'll get some flow numbers and see where I stand. Here's a couple pics of the exhaust port. Before and after. Just have to clean up a couple spots and give it a light polish then I'll start on the intake.

 

This is how the exhaust port started:

 

Here's one nearly completed:

Edited September 26, 2010 by pablo63
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