454 vs 383
Thread Starter
Burning Brakes
Joined: Mar 2004
Posts: 923
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From: Austin Tx
454 vs 383
Have a 400 crank sitting in my garage. I was planning on setting the L-48 aside and getting a used 350 4 bolt block and getting some nice alum hi-comp heads, new cam, make a nice 400hp 383. But if I have to go to the trouble to pull the motor out, and get another block, why not spend a little more and toss a 454 in there. I want to start fresh with another block so my car won't be down while engine is being built. Anybody else here done a SB to BB conversion? I know I need different springs up front, and rear sway bar, accessory brackets...do I really need to upgrade radiator, fan shroud?
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From: Just because I'm paranoid doesn't mean people aren't out to get me...
St. Jude Donor '09
That's the same dilema I was in about 2.5 years ago. I just swapped in the 454 TODAY! 
There was no comparison in torque comparing the SB to the BB. The SB may have a peak torque of 450ftlb, but is takes time to build that peak. I ran many desktop dyno's with different configurations before I made a decision, and in each, the BB always came out with an almost flat torque torque curve starting @2000-2500 with about 400ftlb and going up from there.!
There was no comparison in torque comparing the SB to the BB. The SB may have a peak torque of 450ftlb, but is takes time to build that peak. I ran many desktop dyno's with different configurations before I made a decision, and in each, the BB always came out with an almost flat torque torque curve starting @2000-2500 with about 400ftlb and going up from there.!
Thread Starter
Burning Brakes
Joined: Mar 2004
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From: Austin Tx
Jughead, thanks for reminding me of that point. I had a 69 427 BB but it was totaled when some idiot hit me on the freeway. I now have a 72 SB vert , auto(uggH, too good a deal to pass up though, almost literally free, long story)I have now had my 72 for 6 mos, quick car, but feels like a Ford Temp compared to my previous shark. Good luck with your 454. I will be scouting for one, and making a list of all the other parts I will have to gather.
Burning Brakes
Joined: Aug 2000
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From: Woburn,ma ma
383 vs 454
when i decided to take my L-82 out in place of another motor, I thought about the 454 ,383, and a blown 350.. at the time I didn't know a lot and was afraid of detonation with the blower setup, so I didn't go that way (wish I did) the 454, for what it would cost for the block and the cost of parts are almost double considered to a small block, I then decided that was not the rte I was going, now with that said, I did as much research as one could do on the strokers, and I built a 385, now I may not have those huge valve covers, or a nice blower on top of my motor, I can say, I have 275 dunlops out back, and when I am cruising along in 1st at 2800rpms I can nail the pedal, and get the car to lite up the tires effortlessly and will continue untill the car goes sideways and my tach is at 6000.. so I am pleased with my stroker, just wish I had a blower on top 
Race Director
Joined: Dec 1999
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From: Forked River NJ
If you are going to go to a BB why not go to 502 or larger. A 454 is a small BB. I personally like the big inch SB motors. I think they fit the Vette better. EIther way it will be wayyy better than what you have.
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Melting Slicks
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From: Gulf of America
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If you're after the torque, then the BB is the way to go. If you want the handling (sports car) a SB will have the advantage over the BB.
Thread Starter
Burning Brakes
Joined: Mar 2004
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From: Austin Tx
Originally Posted by MotorHead
Why not put the 400 crank in a 400 block and get big block numbers in a small block ?
Instructor
Joined: Jun 2004
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From: Avon CO
Originally Posted by Mako72
If you're after the torque, then the BB is the way to go. If you want the handling (sports car) a SB will have the advantage over the BB.
I live in the mountains, and while im sure you can modify the car to handle like a sb with a bb, im also sure that would take a large amount of money. That is why i chose to go with a 383, now, i cannot tell you how it works, since i have been building my house and have no time for the vette. So i think its really simple, i really think there is a reason that chevy put so many sb's into their corvettes. Whichever way you go, im sure you will be happy.
Thread Starter
Burning Brakes
Joined: Mar 2004
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From: Austin Tx
Was debating on whether to stroke my 350 to 383 or go with 454...Found out today father in law is letting me have for free 400 SB out of 4x4 Chevy hunting truck that has been sitting idle at the deer camp for 10 years. Don't know what kind of power it had but I did notice it had edelbrock intake/carb on it before they were stolen off of it over the summer. He said when it was running it could spin all 4 35" tires easy...I guess I'll take it off his hands and if a 454 doesn't fall into my lap for cheap prior to next spring I'll just clean it up build the 400 to 406, add alum heads, cam, other goodies and keep my car a SB....
Drifting
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From: Milford Haven Pembrokeshire
