I like the early 90's ZR 1. Engine ......old school HP

Shame it was not made the std Chevrolet engine

 

BB for the WOW factor.

 

Seriously? Do you have any idea what the weight difference actually is?

 

SB = 575lb LS about 460

BB = 685lb


approx.

http://www.gomog.com/allmorgan/engineweights.html

 

Truthfully, the BB is going to win if all out Hp/torque is the only final end result-even if putting the power to the ground becomes more dubious with the BB versus the SB on the street, especially once you pass the 500-550+ number whether SB or BB.

If you are interested in the better overall package-chassis balance-the BB is not the best way to go. Yes, the BB car still has a favorable weight distribution but the SBC in a C3 is noticeable better. Duntov was dead against the BB in the C3 simply because it negatively effected the front to rear weight distribution versus a SB C3 for chassis balance and road racing. The BB dominated racing at the time simply because GM could get more power from the BB cars than the SB C3's-that part of the equation is no longer as relevant today with the power potential of the SBC.

BB C3 Front:51-52% Rear 48-49%
SB C3 Front:48-50% Rear 50-52% BTW-These SB C3 numbers are pretty much the sole reason folks often complain that their cars have oversteer at the limit. Excellent for handling but MUCH less forgiving for the uninformed at or near the limit of adhesion. Later C3's even the gymkhana sports suspension with a rear bar would understeer at or near the limit.

Depends on the year. Yes you can add aluminum heads, radiators, water pumps etc to the BB to reduce the front weight mass but the same applies today to the SB's like my L-82 355 which still leaves the SB with the overall balance equation. The bottom line on weight distribution is that a slight rear weight bias of the SBC is great for balance and the addition of aluminum heads etc to both engines is helpful to handling but still the SB still gets the nod -aluminum heads for both or not.

The beauty of the C3's are that they are well balanced-power, handling, steering and braking-unlike other cars from that era. Other GM cars and it's rivals could go fast in a straight line but handling/braking was secondary.

Depends what you are after….

 

In part a BBC in a C3 is nostalgic and that's what some of us are after. A C3 will probably never handle like a C7, and that's ok for many of us. But, aluminum replacement parts on the BBC will narrow the weight gap with comparable parts on the SBC, so the question is, what does a BBC with aluminum heads, water pump and intake manifold weigh versus a similarly equipped small block? The are formulas that indicate how many horsepower is needed to compensate for additional weight.

 

The best percentage i have seen on SBC is 49 front, 51 rear LT1 stripped with no luxury items. I had a 66 vert no PB,PS,A/C ran both a SBC and BBC in it. Ordered a brand new 73 with a BBC but no A/C.

Problem is back then people had 302,327,350 extremely rare ever a 400 built. BBC were 396,427,454.

But with the aftermarket today the gap has widened much further then it used to be. SBC you will see built 350,383,427,434 maybe on rare occasion you might see one built to 472.

Today they build 454,496,540,555 common as the dirt on the ground, sometimes 632 and you can go much higher then that by a lot if you just want to keep spending money. The airflow you can get in BBC heads is just endless compared to SBC.

There is no comparison of what you can do with a SBC or a BBC in todays world. They have built them to 1015 cu. if you have cubic money to spend.

In a camaro like my 69 Z/28 only thing it had was power disk brakes with the sbc it was around 54 percent on the front, with the longer wheelbase car both engine and trans weight further away from the back axle like it is, you stick a BBC in it you would most likely be at 56 percent on the front now your at the point of extreme under steer problems. But a stripper vette like the LT1 i mentioned with only 49 percent on the front with a SBC you stick BBC in its shorter wheelbase car has far less effect on changing things.


Another thing in a vette the drivers weight and passenger weight is setting very close to the back axle not like on the ill handling pony cars where that weight is also placed further forward.

Putting a slightly more heavy BBC in a vette a non player unless your at the max of road racing.

 

If you have to ask, add 50 hp.

(I read his post as tongue-in-cheek, but maybe I was wrong...)

 

http://www.roadandtrack.com/car-revi...rolet-corvette

Check the link above for a real shocker on the 78 C3:

Front: 46%/Rear: 54% with the driver…..Those are the types of factual numbers that you get with a mid engine high performance sports car-even today and the weight distribution for a road racing sports car-all things being optimized. Not a chance with BB C3….There seems to be this constant theme that the BB C3's don't really have a disadvantage in handling versus the SB C3's which, again, was clearly articulated by Zora A. Duntov, and the facts…Simply not true.

 

SBC-in around 550 lbs (aluminum intake). With 575 with cast iron intake

BBC-in and around 685-700+ lbs depending on options.

The bottom line is the BBC is about 150 pounds heavier than the small block, slightly further forward than the SB C3, and the heavier mass is slightly higher and wider-all effect weight distribution and handling. It is not simply 150 lbs more for the BB versus the SB which is what everyone constantly quotes. Apples to Apples comparison would be a 550 lb SBC engine of the EXACT same dimensions (height, width, depth) compared to
a 700 lb SBC of the same-the comparison here is not that.

 

It's been a while since I've weighed my C3, but the last time I did it was at least 52% rear. I should do that again one of these days. I'm running aluminum heads, aluminum intake, aluminum radiator, long tube headers and electric fans, though, so I've trimmed some fat off the nose of the car. I also switched to a manual (was a 700R4 the last time), so there's some weight gone there as well.

2x what JB said about the weight of the big block - not just more weight, but weight that is further away from the center of gravity.

An aluminum big block would be a fun toy, though...

 

I guess you guys all missed this in the OP first post.

This 1% or 2% and an extra 100 lbs. with a big block is going to be insignificant in a street driven car.

I replaced a 450 hp small block with a zz502 in my '69. Amazing difference, and if you've never experienced it yourself, how can you make a comparison?

 

It's not 100lbs, more like 150 lbs and the weight is distributed differently-see above-3-4% difference in weight distribution.

You are correct that many of us have not experienced a 502 Gross Hp/torque BB in a C3 but the 505 NET HP/Torque in my 10 Z06 is a pretty good comparator for straight line acceleration….Anyone want take a bet on who wins that acceleration run with a 3,080 lb Z06?

 

I use them both,



The little one is used to start the big one......

Really, there is no comparison...and the big ones are animals wherever....

 

I replaced a 450 hp small block with a zz502 in my '69. Amazing difference, and if you've never experienced it yourself, how can you make a comparison?[/QUOTE]

Can you really feel a difference between a 520HP SB and a 600 BB?

 

Can you really feel a difference between a 520HP SB and a 600 BB?[/QUOTE]

BB's are all about torque…which will be noticeable better than a 500+ HP 383. Most of this talk is academic as has been pointed out earlier since in a C3 trying to put down more than 500ft-lbs of torque in our chassis is an exercise in futility…Most of this discussion is really about who has bigger numbers from which engine but in reality you get to a point of BIG diminishing returns on actually transmitting power to the ground or lack thereof …The only reason my 10 Z06 is a scorcher in the 1/4 mile and 0-60 MPH is because it has tremendous ability to get those 505 NET HP to the wheels which is impossible in our 40 years old drivelines...

 

a fat rat with stock heads a cam and some compression will make 500 H.P without leaning on it. a small block won't be as mild mannered at that level and not have the torque. they ran L-88 ,s with the 4 speed or turbo 400 with the stock rear. bolt a set of big slicks on and you may want to make sure the rear is up to snuff.
I've been thinking 496 myself lately as i have one, but 15-1 compression and aluminum rods may not be street able.

 

its not just the weight its all what you mentioned, I do have both big block and small, and like both, but for handling and all round power have to give it to the small block or ls moters. .

 

Concur!

Most will never understand!

 

If you want to put a classical BB engine in a C3...please install aluminum heads and aluminum intake manifold, if necessary. The classical BB in a C3 is a cast iron pig. In 1970, the BB's even came with cast iron intake manifolds. I've driven these C3's with the all cast iron BB engine pigs, and you can really tell it on even just street cornering. They are just too front heavy. My project car is currently slated with an all aluminum BB engine.

If you've got a little bit of bucks, look at installing the C6 Z06 427 in a C3. It produces 505 hp flywheel HP and it's an all aluminum engine not much bigger than a SB. Add 50 pounds to the engine, and buy an A&A centrifugal supercharger...over 700 hp from an engine that, once again, doesn't weight much more than a SB. The C6 Z06 engine is in the GM Performance Parts catalog. The A&A centrifugal supercharger is about $7500. I have this A&A supercharger in my C6 base engine....580 rwhp at 6500 rpm.