Small Block or Big Block?
Thread Starter
Pro
Joined: Dec 2004
Posts: 534
Likes: 2
From: Connecticut
Small Block or Big Block?
Any opinions?
406 SB 520HP - $9K
or
468 BB 600HP - $8K (But need hood, headers, etc.) total cost $11K
For a 1978 with a 4 speed 3.73 gears. Tranny and rear are good.
Just a fun car driven mostly on the street and lots of spinning tires....
406 SB 520HP - $9K
or
468 BB 600HP - $8K (But need hood, headers, etc.) total cost $11K
For a 1978 with a 4 speed 3.73 gears. Tranny and rear are good.
Just a fun car driven mostly on the street and lots of spinning tires....
Race Director
Joined: Jan 2000
Posts: 12,399
Likes: 247
From: San Jose CA
I may be crazy, but I still don't think any small block (G1, 2, 3, 4) can touch a big-block when it comes to maximum potential.
That said, in a stock C3 chassis I think you can easily make "too much" power with a fairly moderate small block build. 400, 500 hp are "easy" to make these days.
That said, in a stock C3 chassis I think you can easily make "too much" power with a fairly moderate small block build. 400, 500 hp are "easy" to make these days.
Racer
Joined: Jan 2014
Posts: 334
Likes: 6
I may be crazy, but I still don't think any small block (G1, 2, 3, 4) can touch a big-block when it comes to maximum potential.
That said, in a stock C3 chassis I think you can easily make "too much" power with a fairly moderate small block build. 400, 500 hp are "easy" to make these days.
That said, in a stock C3 chassis I think you can easily make "too much" power with a fairly moderate small block build. 400, 500 hp are "easy" to make these days.
I love the small block Chevy. Small blocks are easy, cheap, and can definitely be built enough to give me the fun power I am looking for in these cars. But if you want to be king of the hill.....
Pro
Joined: May 2013
Posts: 672
Likes: 31
From: Rapid City South Dakota
If you're talking about STOCK "Tranny and rear are good" they won't be for long behind a 600 HP big block. Remember it's torque, not HP that breaks parts.
Safety Car
Joined: Mar 2007
Posts: 3,652
Likes: 49
From: Bridgewater nj
Big blocks shine but they do invite trouble in a hurry when pushed hard. Breaking the wheels loose at 60-70mph is common and driving into a corner with a set of cobra GT Cooper tires might have you changing your underwear but you'll get use to it!
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
I just installed a 425 HP 383 Ina 79 with a 700R4 trans. It has more power than most can handle. It is near impossible to hook it up Ina hard launch. Honestly on street tires the difference between 520 and 600 HP you will never realize. Neither one will hook on the street. My car has over 500HP in. SB and it is a hoot to drive. Any more HP and it is just bragging rights on the street. Now if you put slicks on different story but you better have a beefed up trans and very good rear end components
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
Had nothing but hot small blocks for years but I will say this no matter wha tthe HP rating is youll never equal the torque of a BB the fun factor is way way worth it.
If I had the funds Id trade up in a hot second
A large CI sbc as mentioned is a valid option also but it will practically cost as much as the BBC. These days a 496 is a small big block but enough to get you in plenty of trouble.
Sure you need to upgrade things but thats par for the course. A BBC doesnt need a bunch of gear or rpm to have a good time. just crack the throttle and you shoot ahead of most real easily
If I had the funds Id trade up in a hot second
A large CI sbc as mentioned is a valid option also but it will practically cost as much as the BBC. These days a 496 is a small big block but enough to get you in plenty of trouble.
Sure you need to upgrade things but thats par for the course. A BBC doesnt need a bunch of gear or rpm to have a good time. just crack the throttle and you shoot ahead of most real easily
Le Mans Master
Joined: Oct 2007
Posts: 7,445
Likes: 971
From: Tennessee/Rhode Island
I just installed a 425 HP 383 Ina 79 with a 700R4 trans. It has more power than most can handle. It is near impossible to hook it up Ina hard launch. Honestly on street tires the difference between 520 and 600 HP you will never realize. Neither one will hook on the street. My car has over 500HP in. SB and it is a hoot to drive. Any more HP and it is just bragging rights on the street. Now if you put slicks on different story but you better have a beefed up trans and very good rear end components
My just rebuilt L-82 355 is easily putting out 425+ Gross HP now and is has unbelievable low end and mid range grunt for a SBC-AFR heads and roller cam. The 355 pulls hard in any gear with the 4 speed with 3.70 gears even down low….As Gordon says beyond 500 HP on the street in a C3 the power becomes more about bragging. I hardly have room to rev the engine past 6,000 RPM in 3 rd gear since most of the time I run out of road. So how can I compare my new L-82 to a BB C3-I can't but I can compare the HP/Torque to my 10 C6Z06 LS7 427 which has a boat load of NET HP and Torque-EVERYWHERE-more than most BB can get to the ground in a C3. The 78 does not have the same punch as the LS7 but its certainly in the game now.You can get 90% of the HP/Torque from a built SB without the mass/weight of the BB. SBC all the way.
Last edited by jb78L-82; Nov 10, 2014 at 06:39 PM.
Le Mans Master
Joined: Apr 2006
Posts: 5,403
Likes: 95
My just rebuilt L-82 355 is easily putting out 425+ Gross HP now and is has unbelievable low end and mid range grunt for a SBC-AFR heads and roller cam. The 355 pulls hard in any gear with the 4 speed with 3.70 gears even down low….As Gordon says beyond 500 HP on the street in a C3 the power becomes more about bragging. I hardly have room to rev the engine past 6,000 RPM in 3 rd gear since most of the time I run out of road. So how can I compare my new L-82 to a BB C3-I can't but I can compare the HP/Torque to my 10 C6Z06 LS7 427 which has a boat load of NET HP and Torque-EVERYWHERE-more than most BB can get to the ground in a C3. The 78 does not have the same punch as the LS7 but its certainly in the game now.You can get 90% of the HP/Torque from a built SB without the mass/weight of the BB. SBC all the way.
Last edited by Little Mouse; Nov 10, 2014 at 09:09 PM.
Race Director
Joined: Dec 1999
Posts: 11,094
Likes: 990
From: Sierra Foothills CA
You'd probably be happy with either choice- I love and have both a smallblock and a bigblock. My avatar car has a 355 like "jb" does, except it has AFR 195s, 11 to 1 comp ratio, a more aggressive cam, long tube headers, etc. to go with 4.10 gears. It has a very bad attitude, revs out hard to 6500-7000 RPMs, and yet it still has strong, crisp throttle response just off idle. I love that little engine.
However, my '69 427 has all that and then some. Given your choice, I'd probably go with the bigblock. It can deliver great performance without breathing hard and can deliver eye popping performance when you decide to really let it rip. Truthfully, either of your choices will make enough power to obliterate normal street tires, as touched upon by Gordon. You'll need a good drag radial out back either way. Nitto drag radials could still be overcome too easily on my '69 but MT ET Street Radials now get the job done once they've gotten hot. Heck, that car probably runs the 1/4 mile quicker than my C6 Z06 could because of those tires. Whatever you choose, you're in for a lot of fun.
However, my '69 427 has all that and then some. Given your choice, I'd probably go with the bigblock. It can deliver great performance without breathing hard and can deliver eye popping performance when you decide to really let it rip. Truthfully, either of your choices will make enough power to obliterate normal street tires, as touched upon by Gordon. You'll need a good drag radial out back either way. Nitto drag radials could still be overcome too easily on my '69 but MT ET Street Radials now get the job done once they've gotten hot. Heck, that car probably runs the 1/4 mile quicker than my C6 Z06 could because of those tires. Whatever you choose, you're in for a lot of fun.
Safety Car
Joined: Dec 2012
Posts: 3,974
Likes: 673
bottom line, in a 3000 pound car you need at least 600 to 650hp to be competitive.and you can get that very easy with a small block, but if you do go big with a big block you need to make enough hp to make up for the weight at least 700 to 750hp.
Burning Brakes
Joined: Mar 2014
Posts: 904
Likes: 46
From: Crestline CA
I say go BB. SBs can make a lot of power for sure but the BBs have a the large bore on their side. Big bore=big valves and big valves=big flow at mid lift. People tend to only look a flow at high lift numbers, max flow is only reached once per valve opening while most of the time the valve is somewhere in mid lift. What this means is that you don't need as radical of a cam to make big power with a BB. Besides, BBs don't weigh that much more than SBs especially when you factor in aluminum heads and the engine is so far back in a vette chassis that the weight is less noticeable anyway.
I think if you look at both of you're choices you'll find that the BB makes more power with less cam and the power spread is wider, all great things in a street car.
I think if you look at both of you're choices you'll find that the BB makes more power with less cam and the power spread is wider, all great things in a street car.
