Inliners International Forums General Discussion Engines Lookin for weight of the 302 GMC and the 258 AMC

I'm compiling a table/writeup called "Battle Of The Sixes".
Its goal is to calculate/Gonkulate the effective power HP* of each of the Sixes we might build, all the makes I can find.

Of course its not all the Gonkulator, a lot of the makes are backed up by lots of dyno data (mainly the Nova 6 and the Falcon 6, sketchy to none on some makes).

I'm adding a "HP*" bonus/penalty based on weight so looking for complete engine weights, ie everything unique to that engine. NOT the flywheel, generator, or aircleaner but everything else ie starter, manifolds, carbs, fan. I have no info on the big GMC 302 nor the AMC 258, any numbers appreciated.

This will not be as exciting as a dyno test series but it has been fun for me doing it (learning too) and will share it unless it gets too boring.

A bare GMC head ships at 96 lbs. I have a 302 block and some really good scales so maybe I can drag it out and see what a block weighs.

Weighs more than a BBC, & BBC's are heavy!

MBHD

Roger H uningtons book says 525 stock and teh chevy to be 575. These are figures from his book. I couldn't swear by either one. 1 OL REDNECK

Is the 302 smaller, dimensionally, than a 235?

MBHD

No, the GMC's are longer than the Stovebolt's and taller also.

Gmc will need about 2" more than a chevy. Usually moving the radiator to the front of the support and moving front mounts about 1.5" +/- is about whats required. 1 OLD REDNECK

Found it!

http://www.stovebolt.com/ubbthreads/ubbthreads.php?ubb=showflat&Number=989075#Post989075

I wouldnt have believed the GMC is heavier than the Rat but thats how it looks. About 700lb the way I count em.
All-iron Rat is about 660lb, a 292i6 is about 460lb.

Edit-
Well on rethinking it just now at 5am and looking at Tony's "Lightweight" GMC on the pallet I built an excel sheet to try to make things match.
So I get

790lb, total on their factory "group 1" sheet 270cid
Minus 60 bellhousing, 60 flywheel, 50 clutch etc, 20 generator
(my guesses, I aimed heavy for heavy truck parts, the transmission is 200-300lbs alone!)
600lb dry
620lb wet with oil&water approx
So the 600lb dry would compare to the weight I got for the 194 Nova 6 of about 410lb.

Things jive pretty well now, thats just a little heavier than the stovebolt 235-261. Still though, Tony got a real lightweight, must have been a special all-aluminum "ZL-1" version?

I had a complete GMC 302 shipped to me . It had the bell housing,flywheel, intake and carb,exhaust manifold,generator and starter.
I picked it up at a shipping terminal.The weight sitting on a certified scale,minus the 60 pound pallet, was 575 pounds.
Anyone else ever weighed a 302 on a shipping scale? Seemed a bit light but it was on a scale.

I would tend to go with that. There is no reason for the slight difference in length to cause a great difference in weight between a 302 and a 261. So much is the same or very near the same stuff starter, generator, clutch, flywheel, bell housing, manifolds, cab, distributer, etc. Bigger bore = less cast iron and more aluminum. Bigger journals = less block and more crank. The rods are heavier. By the time you fit it in a car it's not a big difference.

They just cast them thick back then, the GMC blocks can be bored .125 over and still are plenty thick. The deck surface and heads also have a lot of extra iron in them also. They just don't make them like that anymore.

The wall thickness had a single purpose: fewer blocks scrapped when the bore didn't locate accurately within the water jacket.
This also means than many more blocks with less than ideal centering went into service, which can't be bored to those big sizes because the bore as machined is too eccentric in the jacket.

I just remember Mike Kirby saying, somewhat quoting "I don't know why anyone wants to still build a 235 engine over a 194-292 series engine, the 235 weighs more than a BBC"

He builds all those engines, so I would think he knows which engine is heavier. He has to ship some of them.

MBHD

In vehicle design we (FoMoCo) used a general rule of thumb that for every pound of engine weight added you will generally add about a half-pound of additional chassis weight to the car.

Heavier springs, larger tires, larger cooling system, larger sway bar, etc. all contribute to total vehicle weight.

Food for thought

I just shipped a fully enclosed crate with 302 + Fulton visor, extra valve cover, and no flywheel or bell housing and it was 702 lbs. tony, I'd put the motor at around 575-600 lbs.

Here is the same motor with chain, big truck flywheel, pressure plate and bell, along with external oil filter and 12 quart oil pan. By the time you strip all the big truck stuff off, it is quite a bit lighter. It is being lifted here just off the motor stand.

Ken,so it appears a GMC is not as heavy as many think it is. And I bet a 261 Chevy is about the same weight. And a complete cast iron head BBC is around 650 pounds..

I think the gmc is lighter than the 235-261. Just my openion. 1 OLD REDNECK

Thanks Ken a very convincing pictorial.
Must be right cuz you have the same tool chests I do. LOL.
But, my shop is way messier, too much stuff.

So here are the approx weights I have down, I think they are pretty consistent with each other:
356 Ford Six 170-200
408 Ford Six 250
420 Nova Six 194-230-250
460 Tall Six 292
480 Mopar Slant 170-225
490 AMC Six 258-242
490 Ford Six 300
520 Ford Mainline Six 215-223-262
527 Ford Flat Six 226
530 all iron Mouse 283-327
540 all iron Mouse 350-400
560 Stovebolt 216-235-261
565 Ford Flathead v8 221-239-255
575 gmc228
600 gmc302
630 Hudson Big Six 308
685 all iron Rat 396-427-454

I'm trying to cover most of these in the Battle Of The Sixes thing I'm putting together. The biggest surprise so far is how well the AMC and the big Hudson are doing.
No surprise the 292 Chev and the 300 Ford are duking it out for the top spot. Depends which color you like best at that point.

Deuce Coupe,the weights you listed are just the engines or most accessories like water pump, flywheel etc.

The weight numbers I'm giving (some are more accurate than others, comments welcome!!) are as best I can estimate them, just stuff that belongs to the ENGINE but everything it needs to run:

* Complete engine, all cast iron (eg alum intake would be less)
* Carb=yes
* Waterpump=yes
* Starter=yes

* Flywheel/Flexplate/Bellhousing=NO (I give those to the trans)
* Fan=No
* Aircleaner=No
* Water=No
* Oil=No

A lot of those are "reported" weights, as you know there is some scatter in that so these are my best estimates for the above conditions.

A small block Ford is about 520 too. The 490 for the Ford 300 jibes with my data.

I have weight info for most of the Ford engines built in the '70s and '80s, but most are O/T.

This is a fun thread. I hope it's not too far off topic but I'm wondering if anyone knows what all the various old straight eights weighed in at?

Straight 8's hmmm
Not myu specialty for sure but always fascinating.
Approx I have
720 Buick 263 (GUESSING the 248 and 233 are same block ~same wt?)
815 Buick 320 (about twice the Nova 6)

614 Olds 240 and 257 i8
655 pontiac 268 (GUESSING 223-232-249 same block ~same wt?)
752 Packard 359 (GUESSING 288-327 same block ~same wt?)

Pretty sparse. Heavy iron!