331/347 stroker

KdSaint

New Member
Jul 24, 2007
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Florida
I was wondering, not if it's possible, but a good idea to transfrom the stock 302 block into a 331/347 stroker? Does anybody know the pros/cons of each mod; whether I should buy a new block or keep the old one and what's the probable outcome of HP for each?

Thanks,

Saint
 
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In my opinion it's a great idea. If your HP/TQ goals are 450 or less the stock block will be fine. There's no replacement for displacement :D

I'm installing my 331 this Saturday and I'm hoping for 375+ HP/TQ. I selected cam, heads, and intake for a reliable daily driver with plenty of power and good street manners. 450 HP is within reach with a more aggressive cam and great set of heads.

You can make great power with either 331 or 347.
 
i would also go with the 331 if its a daily driver, 347s usually wont last as long

Wrong, just oh so wrong! :nono: Get some experience before clicking the reply button.

Either will be fine for a daily driver. A 347 will make more power across the board assumming the same induction components used. I'd spend the same amount of money to make more power personally and go 347. I like mine :)
 
Wrong, just oh so wrong! :nono: Get some experience before clicking the reply button.

Either will be fine for a daily driver. A 347 will make more power across the board assumming the same induction components used. I'd spend the same amount of money to make more power personally and go 347. I like mine :)

I agree. Longevity is not the issue any more with 347 stroker kits, unless you buy junk parts, and the buillder doesn't know what they are doing. You are gonna spend the same amount whether its a 331 or 347, so why not go for the most power you can make. Not to mention a stock block will only handle so much power regardless of the cubic inches. Ideally if you are aiming for more than the stock block can handle....buy a better block.

BTW my 11:1 CHP 347 w/125 shot is my daily driver, plus it is at the track almost every weekend. It is 2 yrs old with just over 22,000 very hard miles on it. It doesn't use oil, it doesn't smoke, it doesn't get hot, and it never fails to start.
 
yes, 347 are designed better than they used to be and its common now to see 347's as a daily driver. 331 still have a "safer" rod ratio albeit at less power. just so 347 stangers know, i not bashin em. just stating some facts that are worth researching. some 347 kits are designed better than others. they're not all created equal.
 
so with technology today a 347 can be used as a daily driver, as long as the right kit is properly installed. This set up would net me how much HP? 400-450? Less? As for my next question, what would the static compression be? I know that depends on which parts I choose, but I only ask to see if maybe adding some form of FI would be plausible. Most likely not a Turbo, but maybe a small shot of nitrous. I ask only because I want to have a proper plan so I don't just go out and waste money. (That and I want to make sure I can beat those damn ricers.)
 
You'd have to choose the pistons to give you the correct compression ratio to work with your combo - heads, power adder, etc.

If you are going to use forced induction such as a super charger or turbo, you want pistons to give you a compression ration of less than 9:1. If you are only going to use Nitrous, you can go as higher on compression. It all depends on your goals for the engine.

For a daily driver, I'm at 10:1 compression so I can run on pump gas. I can always add N2O later if I want, but my options will be limited if I want to go forced induction in the future due to the 10:1 compression ratio - I won't see as much benefit from forced induction because I will have to use low boost.

I can't stress enough how important it is to decide exactly what you want from this motor before you start to buy parts.
 
That's why I'm just talking about things, trying to see what options are out there, which ones might be in my budget and which ones aren't that common. Plus, at this stage of the game, especially with my poor molested Stang, I'm still working on lightening the car and getting the motor ready for upgrades (i.e. better cooling, more air, etc.) and fixing whatever crap the previous owner screwed up royally, like the torque boxes. Complete junk, need to replace outright. Anyways, my stepdad mentioned "You should turn it into a stroker" and I've just been poking around the internet and asking questions. Who knows, might decide to just get the compressioin around 9.5:1 and boost the crap out of it; I'm just seeing what's possible.
 
That's why I'm just talking about things, trying to see what options are out there, which ones might be in my budget and which ones aren't that common. Plus, at this stage of the game, especially with my poor molested Stang, I'm still working on lightening the car and getting the motor ready for upgrades (i.e. better cooling, more air, etc.) and fixing whatever crap the previous owner screwed up royally, like the torque boxes. Complete junk, need to replace outright. Anyways, my stepdad mentioned "You should turn it into a stroker" and I've just been poking around the internet and asking questions. Who knows, might decide to just get the compressioin around 9.5:1 and boost the crap out of it; I'm just seeing what's possible.


That's good, do as much research as you can before you start and you'll be very happy with the final result. If you are going to use forced induction, go lower than 9.0:1 to get the maximum benefit.

Good luck on your project, take your time and do it right :nice:
 
considering the topic, I thought you all might like to see what I found on ebay.

This car produces 500 horsepower to the rear wheels. The motor is new and was built by Brent Fraizer out of Jacksonville Fl. The car is a every day driver on pump gas. The interior is all custom to match the outside color of the paint. The outside has custom paint job with custom graphics, custom speaker console in the back that is removable. The body kit on the car was purchased from Canada about 2 years ago it was molded on the car at the time. It has 18 inch custom wheels with brand new tires that has hardly been driven on at all. This car was transferred over to a 5 lug system so we could have more options to choose from for the wheels. The car has slotted rotors and color matched calipers and drums. I also have had the car dyno tuned so you will receive the dyno sheet with car. The good news is the car made 500 horsepower with only 8 pounds of boost, the turbo will produce 18 pounds of boost. Below is a list of what is on the car



347 Stroker motor with 100 miles on it

4340 forged Steele crank

H-beam rods with custom forged pistons

ARP main and rod bolts

windage tray With custom oil pan

main girdle

70 mm polished turbo kit with intercooler

AFR 165 fully ported heads

Brand new roller rockers

Solid roller lifters

Brand new Custom Turbo cam

EFI spyder custom intake upper and lower

92 mm throttle body

custom blow through mass air meter

42 pound injectors

custom billet fuel rails with regulator

Aeromotive 1000 fuel pump

Tremec TKO 900 transmission 5 speed with SFI bell housing spec clutch



He may be pushing 500 ponies, but I bet he has to fill up every time he gets stuck at a red light. I don't know if I'd go this far, but at least it's something to consider.
 
wouldnt it be cheaper and just as effective to go with a 351w based motor? then you would not have to worry about your stock block cracking at the 500hp mark
 
my 347 has 11:1 compression on pump gas and the milage isn't all that bad as long as you keep your foot out of it all the time. as far as power 347 all the way! i've owned a few mustangs and i can say this bi%tch moves!! i've taken terminators to zo6's all day long...
 
Yes, a 351w stroked to whatever would net me more power in the end, but it would probably be more expensive considering I don't have a 351w lying around. Unless someone wants to donate one, and all those wonderful accessories (i.e oil pan, wiring harness, etc etc) I'm going to have to go with the 302 block. Money just doesn't grow on trees. :bang:
 
just a thought but would it be feasible to run higher compression and have fun and when ready to run forced induction to just swap in some cometic head gaskets since you can choose thickness? i don't know much about those but i thought i read something like that??? just an honest question to learn more.
 
Yes, a 351w stroked to whatever would net me more power in the end, but it would probably be more expensive considering I don't have a 351w lying around. Unless someone wants to donate one, and all those wonderful accessories (i.e oil pan, wiring harness, etc etc) I'm going to have to go with the 302 block. Money just doesn't grow on trees. :bang:

holy crap, switch to decaff