331 vs 347

Discussion in '1994 - 1995 Specific Tech' started by nunly94gt, Feb 17, 2009.


  1. revhead347

    revhead347 I have face herpes.

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    Yeah, I definately regret not skipping right to a 351 block. The stock block has become a limiting factor. I've had pretty good luck with my 347 though. I'm spraying 150 on my stock block 347. It's held together pretty well. The block will honestly hold 600hp.

    Kurt
  2. 95Vert383AOD

    95Vert383AOD Active Member

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    Then again theres a wise saying "you'll never miss what you never had" :nice:
  3. revhead347

    revhead347 I have face herpes.

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    Yeah, what was I thinking having sex with all those hot chicks in college??

    Kurt
  4. TP Derrick D

    TP Derrick D New Member

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    I have a 331, s-trim, with no problems. When we were deciding between the 2 engine choices, I went with the 331 due to the burning oil myth. I have every 5.0 Mustang and Super Fords magazine since 1997 and every Muscle Mustangs & Fast Fords since 1993 and there were articles aimed at that myth and the 2 engines. On here. as well as other Mustang boards(DFW Stangs, SN95 forums & others) you will get a different answer, most people defending what they have. I learned over all the forums I'm on(I'm also on TALON-a Lightning forum here in north Texas) and its the same way, so I do my own research and go with my findings and gut instinct and hope all work out OK without making a mistake at the cost of other people opinions. Good luck :nice:
  5. nunly94gt

    nunly94gt Founding Member

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    Whats up Stangboy!! You still kicking it around New Orleans?

    I almost did one better today and bought a 68 mustang 289 with a c4. they wanted $900 for the car and it was just the block in the car, no heads intake or carb. but the rust was to much to offer. Anyways, Im just waiting for the right car to come up and im on it.
  6. final5-0

    final5-0 Mustang Master

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    Not so much here, but there are other boards where peeps who own companies that build strokers for a living have laid out all the facts.

    Another thing I find interesting is those peeps have said they are in the business of selling shortblocks and re-educating peeps is not always well received if their mind is already made up.

    I've seen them say they will sell someone what they want and that person will be happy so it ends up being a win win situation for both parties.

    Yes ... Like you said ... The facts are out there :nice:

    I don't take what you find in Mags as being unbiased :nono:

    Grady
  7. stangboy

    stangboy Founding Member

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    Yep, I'm still here! I'm one of the protectors of New Orleans...i'm a New Orleans firefighter. :flag: I haven't been here on the forums since I lost my car in Hurricane Katrina. I just recently bought an 88 coupe so I'm back. I'll probably be on 5.0 Tech a lil more but I'll still peek in at yall SN95 guys. I can't forget where I came from. lol :D

    Its funny you mentioned that you almost bought 68 mustang. A good friend of mine has a 66 coupe for sale. Its partially(actually mostly) restored it has a 331 with a big solid lift cam , AFR 185s, Edelbrock intake(not sure its a Victor Jr or not), Holley 750, longtubes, Top loader 4 spd, etc. all it needs to be finished is a front facia and paint. If you're interested let me know.
  8. nunly94gt

    nunly94gt Founding Member

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    probably out of my price range at the moment. I need something cheap enough to not break me and to be a project for a little while.
  9. nmcgrawj

    nmcgrawj Advanced Member

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    The 351w is bigger stock than a 347. But the rotating weight of a 347 will be much less....making the 347 make more power. In a heavy car, the stock 351 may feel better, but still be slower at the track. Upgrade the rotating assembly in the 351w and this advantage begins to disappear.

    Tagging along with grady....
    I dont trust magazines AT ALL. You have no idea who has who in their back pocket...who is paying who....who is doing who a favor or trying to guide the general public in one directino. Maybe back in 97 the oil burning issue was a problem but now, on this site and many others (hardcore50.com also) there are people who build this stuff day in and day out. I trust their unbiased opinion more than a magazine article.

    There are a lot of people on websites just talking...with no experience. But there are quite a few of very knowledgeable people you can learn from. Rick91gt is one of them.
  10. bubba-dough

    bubba-dough Active Member

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    Me and my pal both went 347, one is boosted - one is sprayed, and we have not had one issue at all. So from experience I would recommend a 347 because I have not had a 331 for comparison.
  11. 95Vert383AOD

    95Vert383AOD Active Member

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    Um 351's font have trouble spinning. but the fact is stock block for stock block the 302 block has a much lower power potential due to the fact that around 500hp they like to split down the middle. Now if you like to be limited to that kind of power you would have been better off keeping your 302, Getting some decent heads/ intake then supercharging/ spraying/ or turbo it. Bigger engines have bigger heavier rotating masses thats a given. But that doesn't really matter when you make it up in cubes. The 347 is at the 302's limit. He could later pull the 351 out and throw a 408 rotating assembly in it. Hell a 2.0 liter Honda has a lighter assembly but its about the potential. Get over the 351 hurdle now and you'll never regret it. Besides 351 will keep you fuel injected and you get to cross over into big block territory when stroked. Nothing like a 408ci 500+ hp motor on pump gas all motor. Get forced induction and you'll be making power on pump gas that a 347 only wishes.

    We don't buy mustangs because they're the fastest sports car. We buy them for the potential.
    Stock 351 has 408 potential "reliably" Dart blocks you can stroke it even further by another 50ci or so.
  12. nmcgrawj

    nmcgrawj Advanced Member

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    LOL so when he drops in his stock 351w shortblock and goes slower than the same parts on a 347....the potential of his 351w will make him feel better huh? I didnt say a 351w cant spin, it just eats up more power because its heavier. At such a close of displacement this matters when u have a stock 351w! Upgrade the rods/crank on the 351w and fine, its a new ball game.

    Im not trying to convince you or anyone else of what to do, just simply pointing out things about every option. Not every person wants or has the funds to make a small block act like a big block. More cubes = better heads = more fuel = more $$$$$$$$$$. Im not saying a 351 doesnt have more potential, it obviously does. Im just pointing out some facts...thats it. Nothing more nothing less.


    -A STOCK 351w shortblock will make an engine/car SLOWER than a 347 because of the rotating weight. The 351w could "feel" better, but the 347 car will run a faster time.

    -Weights of stock and aftermarket rotating assemblies vary. You can get aftermarket parts for the 351w to lighten it up a bit, which then takes away my first point. 4 cubic inches will not make up the difference with a stock 351w. Just making sure no one over looks this fact.

    -To go along with the previous post, not everyone wants a fire breathing turbocharged 408 cubic inch motor stuffed under their hood. Define your goals, decide which is the best path to get there. If his goal is a 400cubic inch motor, or even a 427, why are we even discussing 347s?

    -302's have dart blocks also. Again...define your goals. Some guys are HAPPY with 347s. Some guys are happy with 427s. Some guys regret going as extreme in both cases. GOALS GOALS GOALS....define them carefully.

    -People have said the roller ready 351w blocks are not as strong as the older ones. I believe if you search under Rick91gt's name he has said a 94-97 roller 351w block is only as strong, if not a little stronger, than a 302. Why do you think most aim for late 60's early early 70's blocks?


    The right answer is different for every one of us. Some guys like the idea of having room to grow like you are describing, other guys want a high revving 306, other guys want the best of both worlds and opt for a 302 based dart block. I have had a 351w in my car. I have had a turbo on my 302. I cant imagine stuffing a 351 into my car WITH all the turbo crap. Is it possible? Yep. But space was a headache with a 302, so for me if i wanted to stay with a turbo, i'd probably either get a dart based 302 block or just say forget it, and get used 302 engines and keep blowing those up LOL :rlaugh:
  13. 95Vert383AOD

    95Vert383AOD Active Member

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    Fine then go to a junk yard and get a 351 and buy a 408 rotating assembly. If you build a 347 you shouldn't be using stock heads....toss some big heads on that 408. Heres a link below $2000 for a short block 408 already assembled. Theres many cases of this. For $2000 on a 408 short block why the hell would you build a weaker 347? And it will take 302 style heads accessories, only special parts would be the bigger oil pan/ wider intake lower/ and a distributor. 351 strokers aren't as expensive as people believe.

    http://cgi.ebay.com/ebaymotors/Ford...rms=72:727|65:12|39:1|240:1318#ht_1039wt_1331
  14. nmcgrawj

    nmcgrawj Advanced Member

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    -I would NEVER buy a shortblock/rotating assembly off ebay. What the hell are you going to do if you have problems? Ship it back? Make a visit to florida to the shop? Dont skimp on critical parts. Part of the problems with strokers is poor assembly. Find someone local or a tried, tested, and true builder that has a reputation that others vouch for to build it and then ship it.

    -Mind telling me what year that block is? Your strength argument stands on thin ice when it comes to the roller blocks if im not comfortable at higher power levels with a stroked 351.

    -who said the 347 has stock heads?! LOL You can not put 302 parts on a 351 stroker...yes they bolt up the same but they dont make the power. 347 parts cant be 302 parts. Just like "good" heads for a 302 cost less than "good" 347 heads which cost less than "good" 408 heads. This is simple. Bigger motor = more $$$$$. When it comes time to getting more air in and more air out...stuff gets expensive.

    -I've swapped in a 351 and yes...its fairly straight forward. Thats before the expensive long tubes, expensive $500 lifters if you want a roller cam without a roller block, the 3" exhaust, the headaches when you try to get it in the car, the tall AND EXPENSIVE intakes, the trouble with getting it to fit under a hood, the extra weight on the front tires.

    Some stuff will upgrade in both cases, but dont try to cover up that 351w parts are going to cost more.


    A 351w/stroker is obviously perfect for you and thats fine! But trying to say that there is no point in doing a 347 is just rediculous. People have different goals and there are 1,000 ways to skin a cat....a 351w stroker is not the only way.
  15. bubba-dough

    bubba-dough Active Member

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  16. 95Vert383AOD

    95Vert383AOD Active Member

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    I agree....hahaa its your money...do whatcha like. "Its not the size of the ship but the motion in the ocean" Good thing my woman likes displacement :rlaugh:
  17. nunly94gt

    nunly94gt Founding Member

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    Like I said a while back in this post....I have done the 351w swap it had eddy heads and intake it was fast but its not what I want. Im more of a 302 guy and I had a great setup before. I just wanted to make a little more power with it so I asked which rotating assembly is better.

    As far as Ebay goes....if it doesnt say Eagle or Scat on that rotating assembly I wouldnt buy it. Who knows what your getting and what its made of.
  18. Killercanary

    Killercanary The car that set the bar. Founding Member

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    Nunly94GT- My combo consist of the following:

    -Dart sportsman block
    -Scat 4340 forged crank
    -Scat forged H beam rods with ARP2000 rod bolts
    -SRP dished pistons
    -all internally balanced, compression is 9.0:1
    -75mm accufab TB
    -Holley systemax II intake with a TMOSS ported lower
    -AFR 185 competition heads
    -FTI cam from my old 302 setup
    -1.6 RR's
    -1-3/4" MAC long tube headers
    -Dr. Gas 3" into 2.5" X pipe
    -2.5" cat back
    -ASP pulleys
    -30lb injectors
    -190lph pump
    -AEM EMS

    I just ran a 11.50 at 121mph with this setup in the fall. I haven't dyno'd it yet with the new heads, but it made 380rwhp with the old heads and exhaust.
  19. The O.G.

    The O.G. Member

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    i would only switch to 351 if i got a good deal on it/and not from the junkyard
    maybe a friend with a 90s truck motor running well and i happen to have a few other swap parts

    or wanted a 408
    i would go 347 over ,331 or 351:)
    unless i had a specific reason

    8.2 dart blocks can be stroked pretty far :shrug:
  20. revhead347

    revhead347 I have face herpes.

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    There is a guy in Texas with a turbocharged 347, stock block, making 900hp. He's made a lot of passes on it. Not saying that it's a good idea, but the stock 302 block has been used to make well over 500hp. I've got almost 600hp going through my stock block.

    Kurt

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