SteveR.

I'm planning on getting a C3 this summer, & have been thinking I want a BBC. I've been talking to some people about it, & have a few questions.

This will be a "weekend" car, not a daily driver, but not a show car either. I would like to be able to take it on a road trip a couple of times a year.

Reasons I want a BBC:
1) Its a Big Block. Is there any explanation needed? :)
2) The power is already there
3) I've never had a Big Block
4) That mean Big Block sound

Bad things I've heard about BBCs in C3s:
1) The cars don't handle that much weight up front very well
2) A LOT of heat comes through the firewall, making things uncomfortable (I live in TX)
3) A BB will cost probably an extra ~$5k to boot. (eventually I'll probably spend that money building up a small block though)

So what do you guys think? Are the heat & weight really that noticable? I'm sure some of you have had both SBC & BBC C3s, what is your opinion? What would you guys say the pros & cons are?

Thanks! I really appreciate any help or input.

BlueL36

The downstroke to buy a BB may be a bit more, but unless you burn it up, it'll hold its value. It does generate heat, but you can address that with seals and insulation. For a weekend cruiser, it's a blast. Not the best on gas mileage, so a daily driver it ain't. I've never noticed issues with the extra weight. Good luck with your decision :cheers:

JB

I've owned both. I don't drive real hard, but my BB car seems to handle at least as well as the SB did. I had hot feet with the SB too, so that doesn't seem to me to be a difference either. BB's a lot more fun and the 427 on the hood definitely gets attention. The '69 427 is IMHO the best of the big blocks performance wise, but they're damn picky about fuel. I'm currently running 50/50 93 octane and blue aviation gas to get the performance I like without the pinging.

JB

GWilliam

A 68-72 Vette with a Big Block is the only way to go. You will be disappointed
with anything less in a C3. Don't worry about the handling and all that
nonsense. A stock C3 (even with wonderful VB accessories) handles like
a tank. I don't like high tech, quiet, nimble automobiles. You'll have to
have the same desire if you're serious about getting one.

SteveR.

Thats another thing I've heard about. In the Texas heat, detonation can be a problem with the wrong fuel. I don't want the car to be pinging in 80*-90* weather...how much of a factor is that with a BBC?

I've been doing some searching in this forum...most of my questions have been answered a few times already. :) Sorry for all the newby questions.

SteveR.

Also, what would it take to make a 350ci/350hp SBC make 375rwhp? I know a lot about EFI, but nothing about carbs, or how efficient these old trannies & rears are. Would headers & a moderate cam be enough to put 375 to the wheels, or would it require headwork & a cam, or a moderately built stroker? When mods like this are done, does anything need to be done to the carb jetting etc.? I'm guessing not as long as the power increase was moderate.

Thanks!

427Hotrod

For a weekend toy, you definitely want a big block. There is no reason they can't be as reliable as any small block out there. They are used in trucks and tow vehicles all the time and are reliable as a rock.

The best way to look at it, is that with any Hp number you pick as what you want, the big block will do it with less fuss, less breakage and all around less hassle than a small block. Don't get me wrong, I love small blocks too, but it's hard to beat cubes on the street or track.

A 500 hp big block will idle around and putt around all day. Small blocks can make the HP, but are getting pretty serious at that level, though still dead reliable too. Hit 600 and most streetable small blocks are out of the picture. The big block is just starting to act like the small blpock did at the 500 hp level.

It may in fact be cheaper to build a big block. 500-550 hp can easily be made with iron oval port heads, no need for aftermarket stuff. Cast cranks and 3/8" rods, even factory long slot stamped rockers can easily handle that power range and still spin 6500 rpm. Put in a good set of pistons that aren't ridiculously heavy and it will last forever. As far as rings, bearings, cams etc the price difference isn't that much.

Once you start looking at aftermarket stuff, the bottom end parts prices are still comparable, though they are slightly higher. Trick aftermarket aluminum heads will cost a few hundred more, but that is the worst part. At that point you are contemplating 650+ hp.

You'll find that the cost to build a 496 is about the same as a 427. If you buy a 502 shortblock and add some better heads and valvetrain, you can easily have a streetable 650+ hp street motor on pump gas.

Or start out like I and a lot of others have and build a 540 or bigger. Nick (Vettemaniac) here on the Forum has a 540" '72 with a Tremec 5 speed and 3.08 gears. He built it as an absolute torque monster and literally drives it everyday. He lives in Frisco (near Dallas). I've driven it and it is smooth as you would ever want along with the ability to count on it everyday and get sideways in 3rd gear!

All Vette's get a little toasty inside. Insulation under carpet etc helps. I've run mine for years with the 427 and for the last year and a half or so with the 540 and love it. It has driven all over TX in the summer time and it works fine. The advantage of building it big, is that you can build it milder and still have the smae performance.

Running on pump gas can be done pretty easily too. It just takes some tuning. My 540 is at 10.52 and my 427 was at 11.2 (both measured) and they both handle 40* timing on 93 octane with no boosters at all in Houston heat. Actually, a large cam helps pump gas running along with careful assy. and parts picking. I'll probably be upping compression slightly on the 540 soon.

Check around...you can find lots of big block stuff for reasonable prices. It doesn't take high $$ stuff to run VERY fast! :yesnod:

JIM

SteveR.

I'm not really looking to build a huge drag machine right now. Right now I just want to get a decent body/frame, & in a couple of years once I get everything polished up I'll think more about making huge power. I'm just curious, what kind of gas mileage do you guys get in these 500cid cars? :)

Right now I'll be happy with between 350 & 400 HP to the wheels. I don't have the extra money to buy & then build a seriously fast car. In a couple of years, sure...

Corey_68

As far as pinging in hot weather w/the BB it depends on your compression ratio as well as the heads. With iron heads I wouldn't go above 10:0:1, and with aluminum heads 11:5:1. I never had problems here in South Louisiana.


It can be done with 350ci, but it will compromise streetablity some. It would be much easier and streetable with a stroker. To do it with a 350ci you have to have an excellent set of heads along with the cam and intake to match. A moderate cam isn't going to cut it. A new Z06 "only" makes 350RWHP and has 15% drivetrain loss. Think about it you are trying to get 375RWHP from an engine that has a tranny (TH400 or Muncie 4spd) that soaks up 20% drivetrain loss.

There is an aurora around Big Blocks, I have one myself. If you are looking for all around performance, a stroked SB is the way to go. It has lots of power from a light weight package and cheaper to build.

I could have built TWO small blocks for the price on my Big Block.

My .02

:cheers:


[Modified by Corey 68, 10:46 PM 12/30/2002]

Ih2lose

I have a 1966 427/425 and power shifting it at 6300 rpm PLANTS YOU IN YOUR SEAT.
I have owned and been in some real HOT small blocks both ford and chevy And it the torque of the big block thats so exciting.I realley cant exspain it.

But I never liked corvettes nor had an intrest in them until I went in a ride in a 1967 427/435 coupe with a great driver power shifting this beast,Buy the time he hit third gear I knew I had to have a big block corvette and purchased mine with in 3 weeks of that drive.I am trying to aquire a 1962 to install a big block in it with a tube frame and a C4 suspention under it.

My next aquistion after the 1962 will be a 1974 big block convertable any color except green The 74 I would purchase tomorow if I found one I just want a clean un touched car needing tlc not a restoration (I cant afford to restore another car) As you can tell I love the pull of a big blok

SteveR.

Right now streetability is a big concern. It'll be a weekend cruiser, but I'd like to take it on a road trip a couple of times a year as well.

If anyone wants to let me borrow their BB car for a month so I can make the best evaluation possible, I would be open to that. :D Just let me know...


[Modified by SteveR., 10:48 PM 12/30/2002]

VetteLS6

money!!!!!!!!!!! :troll

Glenn454

I have an original big block car and the motor is modifed. But I can always put it back original. A Big block car convertible or coupe will be worth more in the long run. If thats not important to you build a 383 or 406 small block vette. With the right parts they can make as much power as a bigblocK. Like (Corey 68) said, lots of power from a light weight package and cheaper to build.

73 LS-4

Don't let anyone tell you a BB car can't be made to handle, they can. They just normally take a little more work then a small block car to do it. Stock they handle like truck, not a whole lot of fun in the turns. Put it on a diet, put on some modern wheels and tires, and upgrade the suspension a bit and they become very confident handling wise, It was quite the attention getter at the last autocross I went to, don't see many BB vettes at many of those I guess :lol: As far as the heat goes, mine is bad about it, but a lot of it may have to do with the headers and I haven't upgraded any of the heat shielding for under the floor. It has a tendency to cook my right foot on long trips but it's not a major issue with driving it more of a nusance. About the time my foot gets real hot it's time for me to get more gas anyway so it cools off while I'm pumping gas. With most of these expect somewhere between 9-12mpg if you keep your foot out of it. The low maintenance BB's are the L-36's, LS-5's, and LS-4's, these are the hydralic valvetrains with a single quadrajet, most of these are very well mannered on the street and can keep there cool somewhat in traffic. Now the L-71's,72's,88's, LS-6's and there like are the legendary BB's stories are told about, but these tend to be a little more finicky then there more sedate siblings in daily driving duties.

:cheers:
Pat Kunz

Larry B.

I've had both... Can't say that a BB car handles worse. My 69 with A/C never gets hot inside even here in Florida. I drive it daily, not problem except fuel. Amoco 93 works, others don't... You just need to find one has not been "Bubba-ized"

BB wowbagger

:iagree:

Thats the difficult part of it.. :lol: :lol:

MassVette

If you have reservations about big blocks, you shouldn't get one. The small block is a great motor, plus it'll allow us Rat Packers to have one more BB Corvette available for us!
:lol: :lol: JUST KIDDING!
The Big Blocks I own handle very well (especially the '79), but they are hot in the cockpit. Mileage on my 1979 ZZ/502 2x4 is approx. 15 mpg around town (believe it or not!) The 454 tripower '67 gets around 10 mpg.
Good luck.
:yesnod: :chevy :chevy :yesnod:

GDaina

How does 14" of vacuum and idles at 800, and does not overheat while idling for 40 minutes in 90+ temp sound? During the summer's non rainy days, the 68 is my daily driver.

Sure, why not...motels are cheap up here..... :D

VetteLS6

Well for what it is worth my 2 cents, choice is the key here...ask yourself what do you to have and just do it....not based anothers opinion.

I bought mine back 20+ years ago and have not looked with the what ifs'. MPGs aren't the best but I wasn't looking for that when I bought this car. Two summers ago my family moved from NM to here in WA...1721 miles and I drove the Vette here...(14.7-16.2mpg). The top down and note of the BBC in the air. Not the most comfortable ride on the road but it got more looks from other drivers, that made the ride fun. Of course there were times when the Mustang or new Vette would like to see if it was a loud small block needing help or the real deal. Hands down at 65 mph it pulls like a train to 110 with-out downshifting. Down to 3rd can leave you with the grins/mile smile and others quickly looking that rear chrome bumper. The car has been a topic at the track or shopping center.
All BBC Vettes have a certain aura of days gone by. Young and old like them kinda a throwback from a better day. Is one better than the other? Choice will answer that question. Whatever you choose SBC or BBC enjoy it.
:cheers: