Weighing in on BB vs. SB weight (I have data!)

[CCX33911]

After all of the mind numbing discussions about my block is lighter then yours and thus my car is a better handling car…. I thought I would add my 2 cents worth, but I have data….

The 351 stroker consists of a Dart 351W block (9.5”), with aluminum heads, intake, water pump, 4340 4” crank, 4340 rods, steel GT40 style pan. It is pictured here as weighed:

[CCX33911]

The 427 stroker consists of a cast iron 427 block, 428 crank, Le Mans rods, aluminum intake and throttle bodies, aluminum dove heads, aluminum water pump, and steel Canton RR pan. It is picture below as weighed.

Ready for the results (measured with Longacre race car scales):

351 stroker = 467 lbs.
427 stroker = 503 lbs.

Not quite the 150 lbs or 2/3 the weight figures that get thrown around. I know the Dart block is heavier then the standard block (less then 25 lbs), but by the time you add a girdle to the stock block… The main differences are the Dart engine does not have the alternator, brackets and pulleys mounted (FE does). Dart engine does not have carb mounted, or plug wires (FE is complete). FE weight does not include stand, Dart does. Bottom line is that the Dart engine when completely configured and subtracting the stand weight will be less then 30 lbs lighter then the FE. Not much more then the Big Macs we have hanging over our belts

[Excaliber]

So whatt your saying is,,,if the driver lost a few pounds the difference in weight of the modors makes little or no difference?

Ernie

[Jamo]

Not sure what question this answers.

[RACER X #99]

Gary,
That Dart is almost my motor including the AFR heads. I'll pick the Dart in the same car with the same driver to have quicker lap times on a road course.
That BB sure does look pretty if it's looks you want.

Just my unbiased opinion,

Cranky

[Jamo]

But Cranky,

Isn't that Dart gonna ride a little high in the saddle with the engine stand still attached?

[Bob Putnam]

Gary,

Thanks for the information. It just confirms what I had measured. .

By the way - did the FE actually have the alternator mounted when weighed?

[CCX33911]

Bob,
Yes. Both engines were weighed as pictured. The only caveats are that I did not weigh the stand on the Dart motor separately and subtract it out. Also the lifting bar pictured was not on the Dart motor when weighed. I would guess the stand weighs ~10 lbs. When I fully dress the Dart before putting it in the GT40 I will weigh again (and take out stand weight).

[Turk]

Gary,
Thank you for saying what I have ben trying to say for a long time, more scientifically.

I have asked the question over and over again....If the Big Block weighs the same as the small block, WHAT advantage could the Small Block possibly have other than better gas mileage!!

TURK

[RACER X #99]

Turk,
Very simple,

Much better breathing cyl heads.
And as you know that's the most important part of a high performance engine.

Geeze, how long have you been selling those brand X cars with the free flowing heads.

Now don't ask again.

Cranky

[Richard Hudgins]

Hi folks,

What I would really like to know is the CG location for both engines.

You know, altitude and position for/aft.

Anybody know?

[concobra]

To Racer X #99:

I am very interested in your statement regarding "better breathing cyl. heads" Would you mind sharing your flow number table? Also your CID plus HP@RPM and Torque@RPM numbers.

[RACER X #99]

ConCobra,
There is no point in arguing about the bb vs small block. If
you are happy with the FE then that's what you should run. The problem with the FE as a serious race engine for TODAY is the restrictive exhaust ports. The intakes can be made to flow just as good and some(tunnelport) better than others.
Hot Rod just did a buildup of a Shelby all Aluminum FE with realigned exhaust ports and all the best parts they could find. Max HP 1200, hardly enough to keep up with the BB pro stock motors from the General.
I had always been a fan of the FE and I still think it was one of the best engines for its time (60's) but the other guys big and small have made it an engine best left to nostalgia racers and Cobra street cruisers, and restoration projects.

Cranky,

You asked about flow numbers
http://www.pinn.net/~nascar/fordhead.htm

[CCX33911]

cranky,
What issue of Hot Rod was that? I would like to pick it up.

For everyone,
Also I have it from a reliable source that current NHRA Pro Stock car engines put out about 1390 HP at 500 CID.

What is the comparable output power of the NHRA Pro Stock Truck SB counterparts?? I would guess it is below 1200 HP, but I am not sure?

[CCX33911]

Cranky,
Did you have your motor dynoed yet? They finished mine last week but I don't have the curves yet (in the mail).

[RACER X #99]

Gary ,
I read it last Dec. while waiting for a haircut. I have no idea which issue. Last time I looked and he thru the magazine out.

The sb Pro stock trucks are 358 ci I beleive

My engine is not complete yet. still waiting for AFR to ship the heads.

Looking for around 575-600 hp

Cranky

[REAL 1]

While the SB breath better therefore allowing them to obtain better hp figures than an old FE BB when you are talking modified motors and owners looking to take their motors to the edge of the envelope for performance purposes I think the scientific facts establish what I have been saying all along.

Left in stock trim without trick heads etc. etc. a standard BB can out perform a standard spec SB on a road course and handle just as well...ergo the Motor Trend article which documented the BB having a faster time through the slalom than the SB.

I originally stated a while back that I believed the weight difference between the FE BB and a SB was about 50lbs.

Hmmm...right again!

[CCX33911]

I was a bit surprised that mine made 619 ft-lbs at 4600 RPM and 615 HP at 5600 RPM on 10.5:1 compression (dynoed at Keith Craft).

[RACER X #99]

Evan,
Time to step up to the plate and install some trick Aluminum heads on your Nascar Motor. Not many stock FE's around and certainly no stock 351W's around.
Originality is nice for the shows but on the track almost nobody is stock including the FE's you refrence.

That was then this is now the racers by a large majority prefer small blocks, EVEN SHELBY.

Go buy that FIA you always wanted and come join the gang at the track. You can cook can't you?

Cranky

Evan,
Look at Garys post 100 Hp more than you with less cubes. That's why racers want sb's

[REAL 1]

I love to have a track car. No doubt.

I agree. There are modified SB's putting out killer power numbers.

I'll just have to be content for now with an old 427SO putting out 502 hp and 504 lbs of torque. Anymore power I might get hurt!

Thanks for the track invite. It is certainly something I would love to do. Problem is time and kids.