Just like it says...what year and in what vehicles did the roller 351W come in? When my 302 lets go i'm switching over to a 351W and i want a roller.
What year/vehicles can i get a roller 351W out of?
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joel5.0
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joel5.0
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That's a stretch....there's more to it than just saying it's better.
The 351 still has a much stronger block and still has another 70 cubic inches of growing room. If it wasn't for the usual bump in compression that most stroker kits give you, the 351 would be the better engine hands down. It has a better rod to stroke ratio and more potential than a 347.
The down side is a couple hundred extra pounds and loss in hood and header clearance, but most people run a cowl hood anyways and there's plenty of swap headers available now so neither are a huge deal. The extra weight can be offset by a tubular K member and aluminum heads...and any left over weight is going to be easily offset by the extra power you're gonna make.
Since machining a block costs about the same no matter what the block is, why not start with the better foundation?
426+ci > 347ci
joel5.0
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And the "better" R:S ratio will net?...... + what about the difference in weight of the rotating assembly? and again, as I mentioned......"better than a 351w not stroked."
Well i guess if you stick with the bone stock 351 then yeah i'd probably agree, but you're GOING to spend money on the 347 so why not spend that money on a stroked 351? That's my point. In the end you'll make enough power to offset the extra weight, and if you're building a stroked 351 you can opt for lighter internals and the stock block will still be stronger.
Oh, and a better rod to stroke ratio is going to yield better efficiency and longer life.
Oh, and a better rod to stroke ratio is going to yield better efficiency and longer life.
joel5.0
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347 R:S = 1.59 or 1.56
393 R:S = 1.62 or 1.55
408 - 434 R:S ranges from 1.56 to 1.45
How are the stroked 351w R:S "better"? ......isn't it the opposite?.... BTW, I've worked or owned OEM engine setups (not stroked) with R:S ratios ranging from 1.48 to 1.57 ..... and all had over 300k miles on the odometer. IOW, R:S is something not to worry about.
All the power won't offset that extra weight going when slowing down or going hard into a turn?
As for potential for growth...sure I guess the 351W has got it, but unless you plan on taking advantage of it right from the get go....does it really make a difference which one you're using?
Most guys aren't looking to see more than 300-350hp in N/A trim and a stroked 302 is more than capable of achieving those kinds of power figures. Plan on adding forced induction....500hp isn't going to be a problem with that same set up.
At that point, you're only real issue is approaching the strength limits of the stock 302 block. But again....I ask...if 300-500hp is all you're shooting for, what good is spending the additional money and adding the additional weight of the 351W based block when you're not wouldn't be testing the limits of the 302 block anyway?
BlooDReigN
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I don't even know why the extra weight of the 351 is a concern. What is it...50lbs or so? 50 cubic inches > 50 lbs. My car weighs 2900lbs with full interior and a 408. Man...what a heavy car.
The extra strength of the block more than makes up for the extra weight once you start taking advantage of it.
Nitrous here I come
The extra strength of the block more than makes up for the extra weight once you start taking advantage of it.
Nitrous here I come
Maybe you guys rolling around in full body kit GTs are concerned about the extra weight....i'm not. My car weighs 3120 with me in it...that's less than most Fox's weigh without anyone in it.
My point is...i've seen a lot more all motor 500hp stock block 351 based strokers than 347's. Sure, they're out there, but they're pushing the limits of the stock 302 block. Even stroked to a 408, the 351 is a stronger block and i guarantee you a 408 with the same heads and intake setup as a 347 is going to be more fun.
As for stopping and turning, there are LOTS of American Iron Extreme guys running stroked 351s....ask John Lindsey about that one. If you're gonna go so far as to make a 500hp engine, then go the extra mile to put a tubular K member and A arms in it and aluminum heads and you'll almost offset the extra weight of the 351.
My point is...i've seen a lot more all motor 500hp stock block 351 based strokers than 347's. Sure, they're out there, but they're pushing the limits of the stock 302 block. Even stroked to a 408, the 351 is a stronger block and i guarantee you a 408 with the same heads and intake setup as a 347 is going to be more fun.
As for stopping and turning, there are LOTS of American Iron Extreme guys running stroked 351s....ask John Lindsey about that one. If you're gonna go so far as to make a 500hp engine, then go the extra mile to put a tubular K member and A arms in it and aluminum heads and you'll almost offset the extra weight of the 351.
Closer to 95lbs actually.....and that's just the short block! Not to mention its all over the front wheels, the last place you want it. Besides, you talk as though your car weighs 2,900lbs by accident? Just look at the parts and money it cost you to get there? Not every one wants to start stripping out their creature comforts, swapping out their stock suspension components for light weight stuff or deleting their smog equipment to make race weight. If making 400hp+ in N/A trim or pushing the engine past 550hp with a power adder is the goal, then by all means skip the 302 and go with the 351W. But if neither of those options are in the cars, it just doesn’t make sense to incur the added expense, or tack the additional weight to the front end of the car.
Worth it "if" you're going to bother taking advantage of its increased displacement and strength capabilities. Otherwise, it's an unneeded expense/hindrance to have it in there.
And just think how much you could lighten up a 302 based packaged with all that stuff. Not to mention....a tubular-K and A-arm suspension up front might not be in everyone’s budget.....but most stroker kits now a days are priced that they can be.
I say there is no replacement for displacement. So what it weighs 95 lbs more? If the 351 block can support 100 HP more before splitting, your power/weight ratio still comes wayyyy out on top.
Example:
302 car; 550 hp / 3000 lbs = 0.1833 hp per lb
351 car; 650 hp / 3095 lbs = .2100 hp per lb
Or, with more conservative numbers...
302 car; 450 hp / 3000 lbs = 0.1500 hp per lb
351 car; 550 hp / 3095 lbs = 0.1777 hp per lb
Really, using the 450 hp "max" number for the 302, the 351 would only have to support about 14.25 more hp to compensate for the extra 95 lbs and maintain the same power/weight ratio.
Mathematically:
0.1500 hp/lb * 3095 lbs = 464.25 hp
And finally, just to beat a dead horse, for a mild build...
302 car; 300 hp / 3000 lbs = .1 hp per lb
351 car; 350 hp / 3095 lbs = .1131 hp per lb
351 for teh win!
Example:
302 car; 550 hp / 3000 lbs = 0.1833 hp per lb
351 car; 650 hp / 3095 lbs = .2100 hp per lb
Or, with more conservative numbers...
302 car; 450 hp / 3000 lbs = 0.1500 hp per lb
351 car; 550 hp / 3095 lbs = 0.1777 hp per lb
Really, using the 450 hp "max" number for the 302, the 351 would only have to support about 14.25 more hp to compensate for the extra 95 lbs and maintain the same power/weight ratio.
Mathematically:
0.1500 hp/lb * 3095 lbs = 464.25 hp
And finally, just to beat a dead horse, for a mild build...
302 car; 300 hp / 3000 lbs = .1 hp per lb
351 car; 350 hp / 3095 lbs = .1131 hp per lb
351 for teh win!
Ricer math at it's finest.
You're still not getting it....going about it that way is impractical for anything but theory. Power to weight is fine if you're only talking about acceleration alone, but it does nothing for handling, braking, ride, etc. All other things being equal, the lighter car is always going to handle and brake better.....PERIOD.
And even though I've said it 2 or 3 times in this thread already, I'll say it again for those who still aren't getting it....if one isn't planning on making power beyond 400rwhp in N/A form, or isn't going to make enough power with a power adder to split the stock block (500-550hp), then what good does adding that additional weight to the nose of the car do you in the first place?
For an all out drag racer its one thing, but for a daily driver that isn't trying to eclipse my points above....there's really no advantage.
95 pounds is less than your buddy riding along in the passenger seat....really, that's splitting hairs. Trunk mount the battery and you'll offset a third of it.
My car is hardly stripped by the way....it doesn't have any carpet (that only dropped 60lbs anyways, full interior otherwise) and no plastic paneling in the trunk....but i do have a full tool box and a floor jack that i carry around with me at all times so that easily offsets whatever weight savings i got from that. I guess i'm at an advantage having a no option coupe..so i'll give you that. But, 90 or 100 pounds is not a huge deal even over the front wheels. You just need to offset it somewhere else if you're really worried about it.
Put it this way....if you build up an aftermarket 302 block, it's probably going to be close to the weight of a 351 since those blocks are so beefed up. Plus, how much do you think a supercharger or turbo setup weighs? That'll put your 302 set up right up there with a 351 in weight. How many people are running around with huge superchargers right over the front wheels? Do you really think that extra 100 pounds is a big deal when you consider the extra power they make?
If it came down to 500hp with an all motor 351 or 500hp with a supercharged 302, i bet they both weigh about the same and in the end you're gonna be closer to the danger zone with a blown engine than with an all motor engine, especially since the 351 is a stronger block. Once you take ALL that in consideration, remember that you can still put that supercharger on the 351 and make way more power than the 302 based setup is going to allow.
My car is hardly stripped by the way....it doesn't have any carpet (that only dropped 60lbs anyways, full interior otherwise) and no plastic paneling in the trunk....but i do have a full tool box and a floor jack that i carry around with me at all times so that easily offsets whatever weight savings i got from that. I guess i'm at an advantage having a no option coupe..so i'll give you that. But, 90 or 100 pounds is not a huge deal even over the front wheels. You just need to offset it somewhere else if you're really worried about it.
Put it this way....if you build up an aftermarket 302 block, it's probably going to be close to the weight of a 351 since those blocks are so beefed up. Plus, how much do you think a supercharger or turbo setup weighs? That'll put your 302 set up right up there with a 351 in weight. How many people are running around with huge superchargers right over the front wheels? Do you really think that extra 100 pounds is a big deal when you consider the extra power they make?
If it came down to 500hp with an all motor 351 or 500hp with a supercharged 302, i bet they both weigh about the same and in the end you're gonna be closer to the danger zone with a blown engine than with an all motor engine, especially since the 351 is a stronger block. Once you take ALL that in consideration, remember that you can still put that supercharger on the 351 and make way more power than the 302 based setup is going to allow.
My point was expense...If I had to buy all the stuff for a 351 (dist, oil pan/pick up, headers, intake, accessory conversion) an machine a 351, it would be cheaper to make a 347 an reuse the 5.0 stuff I have an maybe put that money into some killer heads. In my opinion there are advantages to both. Max power potiential=351, weight savings/expense=5.0. Bottom line: your car, your money-build what makes you happy!
Ricer math at it's finest.
You're still not getting it....going about it that way is impractical for anything but theory. Power to weight is fine if you're only talking about acceleration alone, but it does nothing for handling, braking, ride, etc. All other things being equal, the lighter car is always going to handle and brake better.....PERIOD.
And even though I've said it 2 or 3 times in this thread already, I'll say it again for those who still aren't getting it....if one isn't planning on making power beyond 400rwhp in N/A form, or isn't going to make enough power with a power adder to split the stock block (500-550hp), then what good does adding that additional weight to the nose of the car do you in the first place?
For an all out drag racer its one thing, but for a daily driver that isn't trying to eclipse my points above....there's really no advantage.
I threw in the 300/350 hp example just to debate that point. The extra cubic inches just make sense all around. And if the extra weight on the nose hurts handling that much, why did they use it in the 95 Cobra R and the Saleen S-351?
Ricer math? Man, I thought it was called "MET 426: Fundamentals of Motorsports". I guess I signed up for the wrong class...
Well, to be fair....the Cobra R had all the smog, A/C, back seat and everything else that wasn't nailed down removed to attempt to offset the additional weight incurred by the 351W up front.....it didn't even come with a radio for god sakes.
It’s fine if you don’t have a problem with it, but me being in my early-30’s, I certainly wouldn’t consider giving up my creature comforts or smog legality in any street car to improve handling, just to shave off a few pounds that really don’t need to be there in the first place. Either way, it although it was quite a performer compared to the stock GT of that era and most certainly one of the coolest Stangs built in the last 30-years, it isn’t really considered anything special handling or performance wise by today’s standards? I mean…what did it run.....mid-13’s? As for the S-351...it was certainly a mover and a shaker, but probably the furthest thing from “run of the mill” there was at the time. Point being, there was a lot more done to that car than just a motor swap. The suspension and chassis and brakes were worked over from one end to the other to compensate for the additional front end weight…not to mention a ton of weight reduction done to get that supercharged hog down under 3,400lbs. Great thinking on Saleens part, but at $55,000 10+ years ago it certainly came at a price.
Not to mention if I recall correctly, even with almost 500hp on tap the car was only good for mid/high-12’s. Not slow by any means, but certainly not impossible to duplicate with the smaller, lighter 302. Especially if it was fitted with a blower like the S-351 was.
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