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How Much More Does a SBC Weigh than a Buick 3.8?

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85 Cutlass Brougham
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How Much More Does a SBC Weigh than a Buick 3.8?

Postby 85 Cutlass Brougham on Thu Mar 26, 2009 1:57 am

I am wondering what the difference in weight is for a Chevy 350 with Iron heads and an aluminum intake vs the Buick 3.8 V6 as it came in a G body? I am thinking around 150 lbs? Also, how much weight would aluminum heads take off? Aluminum water pump vs Iron water pump? I am trying to determine around what my car will weigh when finished vs stock which was around 3200lbs (V6 Brougham 2 door with A/C, power windows and seat), and also trying to figure out a rough approximation of the weight distribution, and how much better it would be with certain lightweight components. Those components would be: Aluminum radiator support, aluminum bumper support, aluminum hood, aluminum/plastic radiator, and some or all of the engine parts listed.
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1985 Cutlass Supreme Brougham (ex pizza delivery beater with 240,000 miles):
355 Chevy- 9.5:1 compression, Comp XE 262 cam, World S/R Torquer heads with 2.02's, Edelbrock Performer, 800CFM Q jet, Camaro ram air system,Edelbrock headers, Comp Magnum roller tip rockers,TH 200 4R, 3.23 rear, aluminum hood, IROC steering box, poly bushings, Eibach springs, etc. Cutlass build thread here: viewtopic.php?t=4982
Also: The Thing That Won't Die-1998 Nissan Frontier, 340,000 miles of pizza delivery.

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midwestls
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Postby midwestls on Thu Mar 26, 2009 7:39 am

Hummm, interesting. I'd like to know this as well. Also does the 4.3 weigh the same as a 3.8? Anyone?
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Geesie
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Postby Geesie on Thu Mar 26, 2009 10:09 am

I recently saw a table with older GM engine weights but I can't find it again at the moment. IIRC, the difference between a SBC and Buick V6 was a little under 200 lbs.
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Postby 85 Cutlass Brougham on Thu Mar 26, 2009 1:21 pm

Well, I will give a bit of a back story to this question. A guy I know just got a 2009 Cobalt SS. I mentioned that I have about 100 more hp than he does, and he says "yeah, but your car weighs about 1,000 more lbs.". I point out that this is not true by asking him what his car weighs, and he says 2900lbs, to which I say mine is about 3400. Well, come to find out, the Cobalt SS weighs 2975lbs. Too much for a shitbox, IMHO. My registration says my car was 3200lbs when new, which I find amusing since 225lbs gets you a much bigger car. Plus, he has a 60/40 weight distribution and I think a V8 G body is around 55/45. Anyhow, I wanted to see what the real weight difference is and also, what the handling difference would be. My car is far from stock and has had weight taken off the nose (about 50-100lbs so far). Both cars have solid axle rear suspensions, but the Cobalt has a Mac Phearson strut front while the Cutlass has a double A arm front with revised geometry. The Cutlass also wears wider tires and will have 12 in front and 11 in rear disc brakes. The Cobalt will have a braking advantage, but maybe not a handling advantage. He also weighs about 100lbs more than me. Oh, and yes...there is a possible friendly race coming from this... If it is at the drag strip, I may be sporting a concealed nitrous system with the solenoids hidden in the A/C box and the lines concealed with black convoluted tubing.

He says the Cobalt SS runs a 13.6, but I saw figures of 14.0 in the quarter. Also it pulls a 0.9g on the skidpad and 60-0 in 115 feet. I know I can beat all but the braking numbers, but I don't know the transient handling difference.
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1985 Cutlass Supreme Brougham (ex pizza delivery beater with 240,000 miles):
355 Chevy- 9.5:1 compression, Comp XE 262 cam, World S/R Torquer heads with 2.02's, Edelbrock Performer, 800CFM Q jet, Camaro ram air system,Edelbrock headers, Comp Magnum roller tip rockers,TH 200 4R, 3.23 rear, aluminum hood, IROC steering box, poly bushings, Eibach springs, etc. Cutlass build thread here: viewtopic.php?t=4982
Also: The Thing That Won't Die-1998 Nissan Frontier, 340,000 miles of pizza delivery.

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Postby 413Cutlass on Thu Mar 26, 2009 1:55 pm

Is the cobalt in question s/c or turbo?
The S/c ones in stock trim can break into the 14 sec flat area.
The turbo ones can tear off mid 13s no problem
Tho seeing it's an 09, it's def a turbo, and it is def a very quick car.
http://www.youtube.com/watch?v=30UxICiLlss
with abit more boost and a good driver I could see one in just about stock trim hitting 12s. I may consider one of these for a DD once the Cutlass gets to be too much to DD.
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Postby 85 Cutlass Brougham on Thu Mar 26, 2009 2:06 pm

I have actually ridden in it and yes, it is a quick little car. Seeing as my goal was only mid 13's with my car, I am now feeling that I aimed too low. I am hoping that when I am done I will be quicker provided he leaves his car stock. Seeing as he had a pretty fast SRT-4 before this, I doubt that will happen.


BTW, when my car is done, it will have a T-5 and a 3.42 8.5 rear end in it which should be worth a little more acceleration.
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1985 Cutlass Supreme Brougham (ex pizza delivery beater with 240,000 miles):
355 Chevy- 9.5:1 compression, Comp XE 262 cam, World S/R Torquer heads with 2.02's, Edelbrock Performer, 800CFM Q jet, Camaro ram air system,Edelbrock headers, Comp Magnum roller tip rockers,TH 200 4R, 3.23 rear, aluminum hood, IROC steering box, poly bushings, Eibach springs, etc. Cutlass build thread here: viewtopic.php?t=4982
Also: The Thing That Won't Die-1998 Nissan Frontier, 340,000 miles of pizza delivery.

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Postby 413Cutlass on Thu Mar 26, 2009 2:25 pm

well what kinda power you puttin out with the chevy?
If you can make roughly 350 at the wheels, with a 3200lb curb weight...
if you can drive you'll smoke his ass.
cobalts are light but only push 250 at the tires stock, but even with just a tune and exhaust they can make 288hp and 317tq.
If he mods it, it's a driver's race. But his clutch is done for once he's pushing more than 315tq to the wheels. So if he's upgraded the clutch, be ready!
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a/c delete
catback

84 Bonneville
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Postby jrm81bu on Thu Mar 26, 2009 3:12 pm

The cutty may have its suspension modded but I think he still has you in the handling department. GM and some mag tests gloated about the handling of the Cobalt at least the SS. Straight drag strip is prolly gonna be close. And ya he's definetly got ya on the braking. If you guys do go head to head make sure you get some video!
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Postby pontiacgp on Thu Mar 26, 2009 3:53 pm

I know I can beat all but the braking numbers


try some EBC green pads in the front and non power brake S10 wheel cylinders in the back and that'll improve your braking...
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Postby 85 Cutlass Brougham on Thu Mar 26, 2009 8:38 pm

I make somewhere between 350-360hp at the crank and 410-425 ft/lbs. I will be running a Centerforce Dual Friction clutch that I found in a stack of tires in my garage (no kidding!). I do plan on a head upgrade in the future, but for now the engine will stay as-is. I have lots of other areas that need my attention right now, unfortunately. Things like having an interior in the car, tires, post-paint assembly, etc. Oh, and A/C. Gotta have it in Florida during the summer.

I know the Cobalt is supposed to handle well, but that would make it all the sweeter if I could out-class it in an antiquated G body.

As for the brakes, plans call for 1LE Camaro 12 in rotors with Caprice calipers up front, and 4th gen F body rotors and calipers out back (and the hand operated parking brake) once I get the 8.5 rear axle. I may go with better calipers up front eventually though, as well as some larger rotors. Then again, it all takes cash, which is something I don't make a lot of right now. After all, even the most resourceful person needs to buy stuff here and there.
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1985 Cutlass Supreme Brougham (ex pizza delivery beater with 240,000 miles):
355 Chevy- 9.5:1 compression, Comp XE 262 cam, World S/R Torquer heads with 2.02's, Edelbrock Performer, 800CFM Q jet, Camaro ram air system,Edelbrock headers, Comp Magnum roller tip rockers,TH 200 4R, 3.23 rear, aluminum hood, IROC steering box, poly bushings, Eibach springs, etc. Cutlass build thread here: viewtopic.php?t=4982
Also: The Thing That Won't Die-1998 Nissan Frontier, 340,000 miles of pizza delivery.

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Postby KrisW on Mon Apr 06, 2009 7:28 am

Here are a few considerations to make about engine weight where Buicks are concerned.

The 455 is 100 pounds lighter than the sbc, stock for stock. Buick engine blocks from the second generation engine platform (not the old nailhead stuff) were all built on lighter castings for the block. I saw the numbers for this demonstrated in a HOT ROD mag from way back where the guy built himself an 11 second 87 Trans Am. He junked the TPI 305 and installed a mostly stock 455 Buick. His front end actually came up a little!

The 350 Buick is almost the same weight as the 455, maybe 25 pounds different. I know this from my engine swapping past. No special springs are needed when swapping around Buick Stuff.

The 3.8 from our G-bodies is based on the older 300-340 Buick casting, not the 350. So, in addition to the front two cylinders, the 350 also has a wider intake manifold and taller deck height. The narrower intake and shorter deck height of the Buick V6 means less weight as well.

You should be in the 150 pound range stock for stock easily (probably more like 200) on your chevy swap. Now, after you add in your aluminum? I wouldn't know. Did you notice much of a drop in your front suspension when you installed your V8? Maybe not if the springs were already worn. I know that when I remove a Buick V6 and replace it with a small block Buick, I only have the slightest of a drop and I usually wanted that anyway. When I have done sbc swaps, I usually had to replace the springs due to the extra weight.

My guess is 200 pounds difference.
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Postby Blake442 on Mon Apr 06, 2009 7:29 pm

Can't remember where I came across this... but I saved it.

Engine Weights
SBC- 575 lbs
BBC- 685 lbs
SBO- 560 lbs
BBO- 605 lbs
Pont- 650 lbs
SBB- 450 lbs
BBB- 640 lbs
Cad- 625 lbs
'85 Oldsmobile 442--Olds 455-TH400
'83 Oldsmobile Cutlass Cruiser--Chevy 350-TH350
Past G's--'81 Regal, '84 El Camino, '79 Cutlass Supreme, '87 Cutlass Salon,
'81 Monte Carlo, '81 El Camino, '79 Malibu Wagon, '81 Century Estate Wagon

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Postby 85 Cutlass Brougham on Mon Apr 06, 2009 8:20 pm

KrisW wrote:Here are a few considerations to make about engine weight where Buicks are concerned.

The 455 is 100 pounds lighter than the sbc, stock for stock. Buick engine blocks from the second generation engine platform (not the old nailhead stuff) were all built on lighter castings for the block. I saw the numbers for this demonstrated in a HOT ROD mag from way back where the guy built himself an 11 second 87 Trans Am. He junked the TPI 305 and installed a mostly stock 455 Buick. His front end actually came up a little!

The 350 Buick is almost the same weight as the 455, maybe 25 pounds different. I know this from my engine swapping past. No special springs are needed when swapping around Buick Stuff.

The 3.8 from our G-bodies is based on the older 300-340 Buick casting, not the 350. So, in addition to the front two cylinders, the 350 also has a wider intake manifold and taller deck height. The narrower intake and shorter deck height of the Buick V6 means less weight as well.

You should be in the 150 pound range stock for stock easily (probably more like 200) on your chevy swap. Now, after you add in your aluminum? I wouldn't know. Did you notice much of a drop in your front suspension when you installed your V8? Maybe not if the springs were already worn. I know that when I remove a Buick V6 and replace it with a small block Buick, I only have the slightest of a drop and I usually wanted that anyway. When I have done sbc swaps, I usually had to replace the springs due to the extra weight.

My guess is 200 pounds difference.


Well, I swapped the springs, rebuilt the front suspension and changed the steering box when I did the swap, so I wouldn't know if it would drop or not. I basically stripped the car back to the firewall and rebuilt everything from there. I even swapped the wiring harness to one from a 1985 GP with a 305 so that all the wires would line up perfectly, and stripped the car of every nut, bolt, screw and bracket so that the swap would look as if GM did it.
Image
1985 Cutlass Supreme Brougham (ex pizza delivery beater with 240,000 miles):
355 Chevy- 9.5:1 compression, Comp XE 262 cam, World S/R Torquer heads with 2.02's, Edelbrock Performer, 800CFM Q jet, Camaro ram air system,Edelbrock headers, Comp Magnum roller tip rockers,TH 200 4R, 3.23 rear, aluminum hood, IROC steering box, poly bushings, Eibach springs, etc. Cutlass build thread here: viewtopic.php?t=4982
Also: The Thing That Won't Die-1998 Nissan Frontier, 340,000 miles of pizza delivery.

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Postby Coveted on Mon Apr 06, 2009 8:38 pm

id be 100% shocked if the sbo actually weighed less than a sbc when its almost the same size as a big block

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Postby Blake442 on Mon Apr 06, 2009 8:43 pm

Believe it!

It's not that the SBO is almost the same size as the BBO, it's that the BBO is almost the same size as the SBO... If you know what I mean... :lol:

The BBO is the exact same as a SBO with the exception of a taller deck height. That's it...
'85 Oldsmobile 442--Olds 455-TH400
'83 Oldsmobile Cutlass Cruiser--Chevy 350-TH350
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