rickybobby111

for a crate motor swap what engine performs the best? i have little experience w/ bb's and was hoping for some opinions... what advantages if any does a bb have over a high power sbc or even a 383? why do so many people swap for nom bb's (besides the rumble) since a sb can put out similar numbers at much less weight?

need input from bb guys on fuel economy, hp/weight/distribution, and how a bb handles (never driven one out of a fullsize)

vettes1st

Low rpm torque. Mileage will be less. You won't notice the extra weight in normal driving. Once you've tried it you won't go back.

Downdraft

I am playing with the idea too - I have matching numbers 300 hp engine - no sense in trying to sqeeze more Hp from it without going the the entire 43 yr old engine - as an alternative I found http://www.steveschmidtracing.com/en...ro-street.html

It has a BB displacement and 619 hp but fits a a SB. Comments??

Alex

firstgear

with extra HP how are you going to get it to the ground?

rickybobby111

i guess my real question is do BB cars handle well? not just cruising but through short track kind of stuff too, and what are the advantages if any of a big block (seems prices are the same for comparable power bb's and sb's)

KyleDallas

Here's a little chart to help you sift your way through the situation..
there's only about 100lbs difference between a small block and big block in stock form... weight wise

http://www.35pickup.com/mulligan/weight.txt

Go with aluminum heads on the BBC... loose 30 to 40 lbs..
Aluminum intake manifold......... loose ??? lbs
Aluminum waterpump..... loose ??? lbs
Mini Starter............... loose ??? lbs...

I think with a little thought you could whittle 50 to 75 lbs away from
the 100lbs different weight..... at that point would you even need
to change springs?? for 25 to 50 lbs???

I prefer bolt on/off mods that you can swap easily if need be...
none of these BB engine mods are permanent.


I got a consistent 15 mpg out of my '66 Olds Toronado with a
425 ci BB...... (stock trim/no mods).... really just depends on
the motor you put in there and how much you flog it.

Penkse won the 24 hours of Daytona in 1966 in a Big Block car that
handled very well.... you should get near SB handling if you get
enough weight off of the BBC.

rickybobby111

that gas mileage thing was my last question, anyone dd their big block?? hows that workin out (mpg and all)??



i'm now thinkin of a gm 454 or a 427 anyone run a one of these w/ an opinion?

sub006

For street performance, forget horsepower. Concentrate on torque and low weight.

A 383 gives big-block power in a small-block package. If you keep your foot out of it, mileage will be equal to a 350. For more power and a little less mpg, go 406 small-block.

pletner

I'm thinking along the same route, although I would like to add a stand alone fuel injection unit like the Holley or Edelbrock. I read an article in Corvette Fever that had a guy and his C3 BB and he was getting 20mpg. with fuel injection.

rickybobby111

didnt think 20mpg was possible for a bb, figured you guys were closer to like 10, anybody know?


thanks for all the input

nassau66427

I'm getting 13 mpg with a 4-speed and 3.08s. That's with a lot of stopping and going. Around here if you can go more than a 1/2 mile without hitting a light you're doing good.

As far as what size motor to get... "There's no substitute for cubic inches."

Kensmith

How about a nice 427 small block. Light weight, lots of cubes, power right out of the box.

sub006

But what's the going price for a 427 small-block? $8,000? $10,000? For that kind of money you can start looking at aluminum blocks, small or big.

Or are you saying just buy a brand new crate Z06?

vic z

I'm in the process of getting the zz454/440hp with the aluminum oval port heads.All you add is your carb,distibutor and starter.Roy just recently installed the zz454/425hp with the rectangular port heads.Less weight plus a 2 year GM warranty.if anyone is interested maybe we can do a mulitple purchase and save some dollars ??? the best price I found is around $6,200 delivered. VZ.

67-427ci

Hi Vic: The block cracked a few weeks ago in my 454/425 crate engine. I just purchased and installed a ZZ454 (Aluminum heads). Price was $5,975.00 delivered to my local Chevy dealer. They beat the online prices. Check out this thread on my install. It is running GREAT. I'll be heading to Texas with it on the 9th.
Roy

Fast66vette

My 66 coupe is an original 427/425 car but I dont have the motor. So I built a 383 stroker and figured it will never be a numbers matching car so I put in a TH350. I'm hoping to put out at least 450hp and tq. It sounds tourqy but the car hasnt seen the road yet. I used a blueprint from....... I cant find the book. Sorry but the numbers off the dyno showed that it put out about 487 hp and 472 ft pounds of tq. This was all on a budget. I will try to find the book. The numbers were also showing very very low rpm tq. Very stoudt motor.