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Weight guessing..

  • Thread starter Thread starter CornerCarvin67
  • Start date Start date Aug 5, 2005

CornerCarvin67

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Guessing... cuz really.... unless you've actually specifically performed this test procedure... it has to be a guess. My question is this: How would the weight of a stock 289 engine with factory steel heads compare to a 351W engine sporting a set of aluminum heads?
 

CornerCarvin67

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I just found a website that has engine weights listed.... 289/302 at 460. 351W at 510. So how much of a difference then is there from the iron heads to aluminum heads? Could it be the 50 lbs between the factory engines?
 

Edbert

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Don't forget the intake weight savings, plus LTHs weigh considerably less than cast iron manifolds. It is just a guess on my part but I'd say my 351W weighs a little less than the stock 289 it replaced.

Then add my roll bar, SFCs, AOD, and 9" weight. Take away some for the rack and pinion and improved brakes, new Bullitt wheels weigh considerably less than the Styled Steel ones they replaced even with larger rubber, and the fiberglass body bits. I'd say my car is within 100 pounds of stock, whatever the case I know I've lowered the CG.
 

CornerCarvin67

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I'm just interested in keeping my car at or below 3000lbs. It's currently at 3010lbs. I still got fiberglass goodies hopefully down the line that can help with that stuff.

I'm just day dreaming about it because I was wondering if it would be better to just go with a 351W instead of stroking a 302. Word is that the 351 makes power easier and cheape than it's little brother.
 

Edbert

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CornerCarvin67 said:
Word is that the 351 makes power easier and cheape than it's little brother.
Click to expand...
Not sure about cheaper, I think they are pretty much even. If by power you mean torque then there's no contest between the two, I'll hit 400fw-ft/lbs at about 2,500RPM and it stays at 400+ all the way to 5.500RPM. The 302s have never been know for their torque. With HP it is closer, obviously the increased displacment helps a lot, but the big Windsors are stout beasts, and the very things that meake them strong and durable also hinder their willingness to rev. A 347 can pretty much equal a 351W in the horsepower category and even with the crazy stroke needed to get 347ci it can rev a little better due to the smaller mains.

But basically you can get 400+fwhp from a non-stroked 351W without even trying, you can get that figure and have tons of vacuum as well as a low idle speed.
 
F

ForceFed70

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Funny... cause everyone says that when you stroke a engine, you mostly improve torque and not horsepower.

And the 351W is basically a factory stroked 302.

These engines are near identical in design..except the 351W has 0.5" more stroke. I don't think saying the 302 "has more torque" is an accurate statement.

As far as weight. I agree with ypu edbert on that one. The 351W with aluminum heads probably weights about the same as a 289 with the factory iron heads.
 

Edbert

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70_Nitrous_Eater said:
Funny... cause everyone says that when you stroke a engine, you mostly improve torque and not horsepower.

And the 351W is basically a factory stroked 302.

These engines are near identical in design..except the 351W has 0.5" more stroke. I don't think saying the 302 "has more torque" is an accurate statement.

As far as weight. I agree with ypu edbert on that one. The 351W with aluminum heads probably weights about the same as a 289 with the factory iron heads.
Click to expand...
Perhaps I mixed in too many displacements while I was rambling, the 302 cannot compete with the 351W in output, the 347 DOES. I certainly did not say that the 302 "has more torque"

Bore size and spacing are the same but the journals on the big Windsor are HUGE, bigger than the FE or Cleveland or even Lima motors.

I don't think the heads alone can bring the 351W down to a 289 on weight, but long tube headers and an aluminum intake combined with the heads can
 
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ForceFed70

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Edbert said:
Perhaps I mixed in too many displacements while I was rambling, the 302 cannot compete with the 351W in output, the 347 DOES. I certainly did not say that the 302 "has more torque"

Bore size and spacing are the same but the journals on the big Windsor are HUGE, bigger than the FE or Cleveland or even Lima motors.

I don't think the heads alone can bring the 351W down to a 289 on weight, but long tube headers and an aluminum intake combined with the heads can
Click to expand...


My apologies.
And yes, the 347 and 351W are pretty much equals in my book also.

I've been told that aluminum heads on a small block shaves off approx 40lbs.
From the numbers CornerCarvin67 found, your right.. it's still heavier by about 10lbs. Also swaping to an aluminum intake would about make them equal.

So we pretty much agree on everything. Where's the fun in that
 

CornerCarvin67

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Okay guys.. well I'll pick up that extra 10lbs when I put on the glass R model apron and glass hood when I dump the steel hood and bumper!!

I just worked so hard to get my car sitting the way it does and I don't want to mess it up by putting a 351 in there. The current 289 does have an aluminum intake and long tubes... so it's not a factory weight. But it should all end up close with aluminum heads on the 351 with the additional fiberglass parts I spoke of. Shoot... I should move the battery to the trunk anyways.
 

67coupe351w

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My 351w aluminum heads weight 22 lbs each.
 
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