Swapping for a big block
Thread Starter
Pro
Joined: Jul 2001
Posts: 660
Likes: 0
From: Pleasant Valley MO
Swapping for a big block
Hi All. I would like to swap a big block in my my '69 350/350 auto. What all do i need to change, motor mounts, brackets, pulleys, flywheel. What other problem will I encounter by doing this. Will my small block hood clear? I will be using a 850 holley and sidemount headers.Any info would be grateful, this would help me decide to go big block or 415 small block.
Thanks for your time Larry :chevy
Thanks for your time Larry :chevy
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
Re: Swapping for a big block (Tominator)
I like big cube small blocks myself. A 415 small block is a good idea. Less weight better handling. The small block hood will not clear. If you use a high rise intake you will definitly have problems with clearance. My .02 cents
Le Mans Master
Joined: Sep 2000
Posts: 5,635
Likes: 4
From: Orlando Floriduh
Re: Swapping for a big block (69vette66)
A big block will bolt right in. BUT... You will need a BB hood and if you want to us any kind of aftermarket intake,carb, etc., you will need the L-88 hood. You will also need all of the accessory bracketing. You will need a flywheel and harmonic balancer if you are using a 454 or bigger as those are externally balanced engines. You will need headers OR Corvette big block exhaust manifolds. (expensive) You will also may need to replace the radiator depnding on what you have in there now. :cheers:
[Modified by silvervetteman, 11:16 AM 2/9/2002]
[Modified by silvervetteman, 11:16 AM 2/9/2002]
Racer
Joined: Jul 2001
Posts: 341
Likes: 0
From: macon, ga
Re: Swapping for a big block (silvervetteman)
I have a 1977 corvette w/ a 454, a standard gm intake , a edelbrock 1910 carb and a 3" k&n filter all under a standard hood. No big block, no L-88. I have heard a lot of guys say that this combo wont fit but mine does with about a 1/2" to spare? Any one care to figure this one out? :confused:
[Modified by ykp53, 12:30 PM 2/9/2002]
[Modified by ykp53, 12:30 PM 2/9/2002]
Burning Brakes
Joined: Aug 2000
Posts: 1,080
Likes: 1
From: Frankfurt, Taunus Hills
Re: Swapping for a big block (ykp53)
I also have a 454 in my 77.
I use a Torker II intake and currently a Holley 4150.
My aircleaner is a Edelbrock Pro Flo.
It all fits under the stock 77 SB hood.
I performed the swap from SB to BB myself, had to change the bracketry and the belt routing. Manufactured some pulleys and brackets of my own by using a lathe and aluminium.
Problem is the radiator - go as big as possible.
If using headers, be sure they clear the steering box and the idler arm.
Mine had contact...... for some time, then the fixed it themself :lol:
BB driving is a great experiece - boatloads of torque.....
All SB guy forgive me, but you just don´t know...... :D
I use a Torker II intake and currently a Holley 4150.
My aircleaner is a Edelbrock Pro Flo.
It all fits under the stock 77 SB hood.
I performed the swap from SB to BB myself, had to change the bracketry and the belt routing. Manufactured some pulleys and brackets of my own by using a lathe and aluminium.
Problem is the radiator - go as big as possible.
If using headers, be sure they clear the steering box and the idler arm.
Mine had contact...... for some time, then the fixed it themself :lol:
BB driving is a great experiece - boatloads of torque.....
All SB guy forgive me, but you just don´t know...... :D
Le Mans Master
Joined: Sep 2000
Posts: 5,635
Likes: 4
From: Orlando Floriduh
Re: Swapping for a big block (69vette66)
Ok. ... you guys do not have 68-72 small block hoods, they are different. That's why big blocks fit... There are no 73-up big block hoods except aftermarket.. :boxing
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Drifting
Joined: Jan 2000
Posts: 1,612
Likes: 0
From: Phoenix Arizona
Re: Swapping for a big block (69vette66)
I am doing the same swap (Mouse motor to 454). The only pain I can see is getting the right pulleys and brackets (P/S, alt, smog pump). :crazy:
I am planning to go with a VintageAir set up, so they include the brackets.
I am not that far yet, so I don't have much else to report!!
That 415 mouse motor isn't a bad deal if you go with it... I just want to see that huge BB under my hood.
Bob
I am planning to go with a VintageAir set up, so they include the brackets.
I am not that far yet, so I don't have much else to report!!
That 415 mouse motor isn't a bad deal if you go with it... I just want to see that huge BB under my hood.
Bob
Safety Car
Joined: Aug 2000
Posts: 3,909
Likes: 26
From: Clymer PA
Re: Swapping for a big block (Bob Turner)
Bob:
Smog pump....we don't need no stinking smog pump! :D j/k
69vette66:
I'm currently switching over to a big block right now too. By far the biggest PITA is trying to track down the correct brackets. Purchasing new big block brackets is quite expensive too. The big block will bolt right in for you, but your hood is going to have to change (big block hood or an L88 hood).
After my first ride in a big block car I knew that I just had to have one! The torque of a big block is just out of this world. Don't get me wrong, small blocks are nice, but my God THE TORQUE! Which ever way you decide to go (big block/small block) I'd definetly go for cubic inches.
[Modified by bence13_33, 10:21 PM 2/9/2002]
Smog pump....we don't need no stinking smog pump! :D j/k
69vette66:
I'm currently switching over to a big block right now too. By far the biggest PITA is trying to track down the correct brackets. Purchasing new big block brackets is quite expensive too. The big block will bolt right in for you, but your hood is going to have to change (big block hood or an L88 hood).
After my first ride in a big block car I knew that I just had to have one! The torque of a big block is just out of this world. Don't get me wrong, small blocks are nice, but my God THE TORQUE! Which ever way you decide to go (big block/small block) I'd definetly go for cubic inches.
[Modified by bence13_33, 10:21 PM 2/9/2002]
Thread Starter
Pro
Joined: Jul 2001
Posts: 660
Likes: 0
From: Pleasant Valley MO
Re: Swapping for a big block (bence13_33)
Man you guys are making it hard on me, Big Block or a 415 small block. I like the idea of a 415, but i like the big block. I am not going with a crate motor, I will build from scratch. I have the 400 sb and i found a older 454 complete, so it just deciding which i want to do, before i paint my car. just about ready for primer then i will build motor. Yes they do make sidemount headers for big block vette with side pipes, I already checked it from my sources.
Thanks for all your input Larry :chevy
Thanks for all your input Larry :chevy
Instructor
Joined: Feb 2001
Posts: 163
Likes: 0
From: Milan MI USA
Re: Swapping for a big block (69vette66)
Personal experience is the big block is the way to go.Sold my tweaked 69 small block coupe to my dad and bought a 68 convertible with a 454 .We've driven them back to back and the set you back in your seat torque .Theirs no comparison .Big blocks make their power down low with out having to wring them out,for the same #s.I feel the flames at my neck already .I was a firm believer of small blocks even built a 391 stroker. But one big block ride is all it took.Then the cam comparison and rpm differences and i was hooked. :chevy :chevy
Race Director
Joined: Apr 1999
Posts: 15,133
Likes: 477
From: NM
Re: Swapping for a big block (69vette66)
One thing not mentoned so far is stronger front springs to handle the added weight. Then you may need to make so changes in the rear to ballance the suspension.
tom...
tom...
Le Mans Master
Joined: Sep 2000
Posts: 5,635
Likes: 4
From: Orlando Floriduh
Re: Swapping for a big block (69vette66)
In all fairness here, I have had both. I do prefer big blocks but.. They do have a few drawbacks. They do not tolerate as high of compression ratio without pinging. 93 octane is a must. They tend to run hotter in Corvettes. They are very senistve to timing/temperature changes. They will never get the same gas milage as the small blocks. With your 69, even the stock 454 intake an Q jet (unless it came from a 70-72 corvette) may not fit under a standard big block hood. Those manifolds are "low rise" designed for Corvettes. I don't believe there are any aftermarket manifolds that will work. Maybe someone knows? :eek:
Race Director
Joined: Apr 1999
Posts: 11,520
Likes: 13
From: CORVETTE 77 385 C.I. TEXAS
Re: Swapping for a big block (ykp53)
I have a 1977 corvette w/ a 454, a standard gm intake , a edelbrock 1910 carb and a 3" k&n filter all under a standard hood. No big block, no L-88. I have heard a lot of guys say that this combo wont fit but mine does with about a 1/2" to spare? Any one care to figure this one out? :confused:
[Modified by ykp53, 12:30 PM 2/9/2002]
[Modified by ykp53, 12:30 PM 2/9/2002]
:cool:
Le Mans Master
Joined: Jan 2000
Posts: 8,721
Likes: 108
From: Canada
Re: Swapping for a big block (69vette66)
Tough choice, I have a 72 so a bb means a new hood for me as well. BTW what are you going to do with the "losing" entry? Can we start a line now, oh ya can I be first in line, :yesnod:
Good luck but I get the sence that the cu. and torque are winning. :cheers:
Good luck but I get the sence that the cu. and torque are winning. :cheers:
Le Mans Master
Joined: Oct 2000
Posts: 6,563
Likes: 2
Re: Swapping for a big block (69vette66)
Big block is the way to go; MUCH more torque........Pulleys and brackets are expensive from Corvette suppliers, but half the price for BB Camaros (SAME brackets and pulleys!) Here's a url:
http://www.classicindustries.com
Hey, you C-2 guys-- check out the teak wheel for the Camaro; look familiar? It's half the price, too!
:yesnod: :chevy :chevy :yesnod:
http://www.classicindustries.com
Hey, you C-2 guys-- check out the teak wheel for the Camaro; look familiar? It's half the price, too!
:yesnod: :chevy :chevy :yesnod:
