has any one installed a 347 stroker kit on a 91 f150 4x4 supercab. i'm looking at this because i need more pulling power from my truck. will i need to install larger injectors? a chip and new fuel pump? don't want to bite off more than i can chew and now get the results i'm hoping for. thanks for any input.

 

Go for the 331 instead of the 347. 347 has some reliability issues.

 

Don't stroke a 302. A 351W can be built cheaper, it is stronger to begin with, installed with the same amount of trouble, and make more power!

I'd go with new heads (GT-40 irons or GT-40P), 208/214 cam on a 114lsa, and a rebuilt 351W with compression! Get it to about 9.5:1 or a tad higher and you will easily get 350 HP. Use quality bearings and ARP hardware. Be sure to get it bored with torque plates also and get the rotating assembly balanced.

Fuel wise get a set of 24lbs/hr and you can adapt Mustang fuel pumps for more flow.

I would convert to MAF also. It will make tuning easier also. You can also burn a chip to get around this.

Many parts can be purchased for a lot less used. Heads about $500 or less. 351W used short block for under $200.

HOPE that helps.

 

Well.....I would ask why you want to do that.
Just to gain some torque?

Turbo baby
turbo/s

 

look for a "74" casting block. This is one the best they
made. The casting number is on the rear of the block near the starter. Should be a "D4" something. This particular block can be bored and stroked out to something like 427 cubes. Lots of them out there. Happy hunting

 

Can't the 347 be made from an SVO 351W block with a 302 crank and 4.10" pistons? I don't think this is a good truck motor, but would make for a good race engine.

 

1974 Blocks have a higer nickel content is why they are stronger. They also have a 2 piece rear main, which is a PITA to deal with.

I know someone who had a 408 built by Keith Craft Racing on a 1974 block and before he drove it, the rear main was leaking. They even stipulated that the older blocks have that problem.

If you are not building an all out racer stick to a 1984+ block for a 1 piece rear main. You will avoid headaches. Ever changed a rear main on a 1 piece block? It is a PITA, even moreso on a 2 piece.

I am sure you could destroke a 351W but why the heck would you want a 347 instead of a 351W? A 351W is bigger and stronger! 347's do not stroke well for reliabilty reasons.

A 3" 302 crank and a 4.100" bore will give you a 317 motor. Only an SVO 351 block can be taken .100 over. I wouldn't go more than .060 on a stock 351W block and no more than .030 over on a 302.

You can make a 427 out of any 351W with a 4.125" crank and a 4.060" bore. A 422 is stronger as the bores are only 4.030"

BASICALLY, it will cost more to stroke a 302 than a stock rebuilt 351W, and you still won't have the same cubic inches. A 351W is bigger and stronger!

 

yupper, the main reason is for more torque, i pull a 23 ft trailer, 14ft boat all the fixings, and a fiberglass topper, the 302 is just not quite powerfull enough, having said that should i be looking for a 94, 95 diesel?my truck isn't worth very much but ikts been good considering everything thanks for the input

 

I don't see why a rebuilt 351W or a stroked 351W to a 392 wouldn't be sufficient to tow that boat.

A 392 can be made cheaply...$300 for a cast 3.85" crank. Stock 351W rods (5.955"). 302 Pistons (1.61 comp height). Figure with about $500 in machine work you'll have a short block for about $1200 give or take.

Use a set of GT-40 irons (saw a set sell for $300 with 46K mi) and a decent cam like a 208/214 or a 214/220 on a 114lsa.

You will need bigger injectors for sure and a MAF conversion or a hardcore tune and chip.

That should make about 400 flywheel HP, even more with better heads and a slightly larger cam.

My planned setup is... 1984+ 351W, .030 over, 3.85" Scat crank, Eagle Rods, Speed Pro pistons, converted to roller lifters, AFR-185 heads, 216/224 114lsa cam, 1.6:1 rockers, Edelbrock 351W EFI intake, 30lbs/hr injectors, about 9.5:1 to 10.5:1 compression, and all ARP hardware. That should make close to 500 flywheel HP or about 400rwhp.

Diesels are loud and stinky. They also use tons of oil for changes and require expensive maintainence. They make a ton of torque tho'. Unless you tow all the time, a hi-po gas motor will pull anything.

 

as far as reliability of the 347, depends on the pistons that you use. most have oil ring in the pin hole, thin rins too.which sucks. oil consumption is high.Probe industries makes a stoker kit that uses better designed piston and i thing its like 342 ci. stroker rod length is 5.400. this weekend i boke the crank after 70000 miles.

im replacing the 347 with a 392 stroker. alum gt 40x heads, not the p heads. did away with the speed density and wnt back to carrburation.
rebuilding c6 tranny at this time also.
pulling power was great with the 347 but dollar for dollar build a 351 it has a longer stoke than the 347, good oil consumption and will make plenty of power

 

I think Coast High Performance has it figured out. They use a shorter rod (5.315" I think) instead of the 5.4" rod. They also use different pistons to move the pin down.

Why use GT-40X aluminum heads? There are better flowing heads out there for that sorta money, like TFS-TW or AFR. Unless you already have them.

Thanks for supporting a built 351W or a stroked 351W, it is smarter, more cost effective, and will make more power!

 

Hitman,
i got the brand new still in the box x heads on ebay for 300 bucks he never set a min.
his loss. dont get me wrong the 347 was a tourge producing motor but theres no subsite for cubic inches, as the women claim...bigger just feels better

 

Hitman,
i got the brand new still in the box x heads on ebay for 300 bucks he never set a min.
his loss. dont get me wrong the 347 was a tourge producing motor but theres no subsite for cubic inches, as the women claim...bigger just feels better

 

I don't want to disappoint you but you can not put 1500 dollars into your truck and get a stroker back out. If all you want is to tow your trailer you are a million times better off to buy a truck that is MENT to haul that much. On the other hand, if you are big into restoration and plan on keeping your truck for the pure enjoyment of having an old truck with some get up and go, then a stroker might be the ticket. But what appears to be innocent fun will turn into a vicious cycle, there is really no way of getting around it. Transmitions need to be upgraded and beefed up, rear ends same thing. How about stopping? That is a comfortable feeling to know you can stop quick if you underestimate your acceleration. You will just about have to replace all of your EFI with new. A new engine will demand much more and put an extreme strain everything. New injectors (possibly bigger), fuel pumps (both inline and intank), fuel pressure regulator, maybe clean out the fuel lines. The ignition modules will need to be replaced with new, or possibly upgraded to the MSD setup. A Mass air conversion (~$700) will be needed for the stroker unless you know someone who is very good with burning custom chips were they can dyno your truck. As you can see, strokers are VERY costly, especially when all the little stuff is added up.

 

5500 in my 347, buld a 351 a whole lot cheaper