What makes a 383ci??
01-16-2006, 01:46 PM
#1
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What makes a 383ci??
Justk a quick dumb question, how do I convert my 350 to a 383?
Is it just a matter of Honing the cylinders to 4.030 and a new Crank? or is there something else I havent' read about.
Any comments are welcome !
Is it just a matter of Honing the cylinders to 4.030 and a new Crank? or is there something else I havent' read about.
Any comments are welcome !
01-16-2006, 02:28 PM
#4
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Re: What makes a 383ci??
pros:
more displacement typically generates more power, longer stroke builds more torque, rebuilding allows for use of better parts
cons:
thinner cylinder walls could cause problems, particularly with boost. more stress on parts, so quality is important.
more displacement typically generates more power, longer stroke builds more torque, rebuilding allows for use of better parts
cons:
thinner cylinder walls could cause problems, particularly with boost. more stress on parts, so quality is important.
01-16-2006, 02:46 PM
#5
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Re: What makes a 383ci??
Originally Posted by teke184
pros:
more displacement typically generates more power, longer stroke builds more torque, rebuilding allows for use of better parts
cons:
thinner cylinder walls could cause problems, particularly with boost. more stress on parts, so quality is important.
more displacement typically generates more power, longer stroke builds more torque, rebuilding allows for use of better parts
cons:
thinner cylinder walls could cause problems, particularly with boost. more stress on parts, so quality is important.
And if I honed the block & keep the same rotating assembly would it make any dif in power gains? or is it point less?
01-16-2006, 03:31 PM
#6
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Re: What makes a 383ci??
To open up the cylinder bores, you "bore" them. Honing tends to be more closely associated with cleaning up the surface finish, minor dimensonal corrections, etc.
You don't HAVE to build a 383 (its actually a 382.67). That's what you get by overboring the cylinders by 0.030", and replacing your 3.480" crank with a 3.750" crank. To reduce concerns about cylinder wall thickness, or to preserve more of the existing wall thickness for future rebuilds, you can consider boring something less the 0.030". I built a "381" (actually a 380.77) with an 0.020" overbore.
Some people have gone absolutely nuts and taken the LT1 block out to an 0.090" overbore, but that takes a careful dimensional analysis of the cylinder wall thickness and concentricity, recentering the bores for optimum thrust wall stength and a bunch of other stuff. It isn't cost effective, and the few cubic inches difference between an 0.020" overbore and an 0.090" overbore are not going to make much difference.
If you bore the cylinders, you need to buy new pistons.
Your current engine is 350ci (actually 349.85). If you were to rebuild it, you might consider keeping the stock crank throw at 3.480", and boring it out wo 4.030". That gives you a 355 (actually 355.12). To get an relative idea of the power potential of each configuration, a rough way to look at it would be simple dividing 383 / 355 and realizing that the 383 gives you about 8% extra displacment, which in rough terms should allow you to make 8% more power, assuming you can supply the extra 8% air with your head and cam selection
You don't HAVE to build a 383 (its actually a 382.67). That's what you get by overboring the cylinders by 0.030", and replacing your 3.480" crank with a 3.750" crank. To reduce concerns about cylinder wall thickness, or to preserve more of the existing wall thickness for future rebuilds, you can consider boring something less the 0.030". I built a "381" (actually a 380.77) with an 0.020" overbore.
Some people have gone absolutely nuts and taken the LT1 block out to an 0.090" overbore, but that takes a careful dimensional analysis of the cylinder wall thickness and concentricity, recentering the bores for optimum thrust wall stength and a bunch of other stuff. It isn't cost effective, and the few cubic inches difference between an 0.020" overbore and an 0.090" overbore are not going to make much difference.
If you bore the cylinders, you need to buy new pistons.
Your current engine is 350ci (actually 349.85). If you were to rebuild it, you might consider keeping the stock crank throw at 3.480", and boring it out wo 4.030". That gives you a 355 (actually 355.12). To get an relative idea of the power potential of each configuration, a rough way to look at it would be simple dividing 383 / 355 and realizing that the 383 gives you about 8% extra displacment, which in rough terms should allow you to make 8% more power, assuming you can supply the extra 8% air with your head and cam selection
01-16-2006, 03:52 PM
#7
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Re: What makes a 383ci??
There's more to it than just displacement, the longer stroke plays big time into the low end grunt these stroker can produce-take 2 identical motors other than the fact ones a 350 and the other is a 383, the 383 will shet and get all over the 350...been there done that, cant argue with the extra stroke.
if your going to run N/A, you dont have to have premium parts either, I'm a perfect example of stock parts making gret power and lasting a long long time with the car getting beat everytime it's started up. With the older blocks you can safely go .060 overbore but anymore than that your pushing your luck wihitout block filler to help strengthen the cylinder walls.
if your going to run N/A, you dont have to have premium parts either, I'm a perfect example of stock parts making gret power and lasting a long long time with the car getting beat everytime it's started up. With the older blocks you can safely go .060 overbore but anymore than that your pushing your luck wihitout block filler to help strengthen the cylinder walls.
01-16-2006, 04:04 PM
#8
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Re: What makes a 383ci??
Originally Posted by Injuneer
To open up the cylinder bores, you "bore" them. Honing tends to be more closely associated with cleaning up the surface finish, minor dimensonal corrections, etc.
You don't HAVE to build a 383 (its actually a 382.67). That's what you get by overboring the cylinders by 0.030", and replacing your 3.480" crank with a 3.750" crank. To reduce concerns about cylinder wall thickness, or to preserve more of the existing wall thickness for future rebuilds, you can consider boring something less the 0.030". I built a "381" (actually a 380.77) with an 0.020" overbore.
Some people have gone absolutely nuts and taken the LT1 block out to an 0.090" overbore, but that takes a careful dimensional analysis of the cylinder wall thickness and concentricity, recentering the bores for optimum thrust wall stength and a bunch of other stuff. It isn't cost effective, and the few cubic inches difference between an 0.020" overbore and an 0.090" overbore are not going to make much difference.
If you bore the cylinders, you need to buy new pistons.
Your current engine is 350ci (actually 349.85). If you were to rebuild it, you might consider keeping the stock crank throw at 3.480", and boring it out wo 4.030". That gives you a 355 (actually 355.12). To get an relative idea of the power potential of each configuration, a rough way to look at it would be simple dividing 383 / 355 and realizing that the 383 gives you about 8% extra displacment, which in rough terms should allow you to make 8% more power, assuming you can supply the extra 8% air with your head and cam selection
You don't HAVE to build a 383 (its actually a 382.67). That's what you get by overboring the cylinders by 0.030", and replacing your 3.480" crank with a 3.750" crank. To reduce concerns about cylinder wall thickness, or to preserve more of the existing wall thickness for future rebuilds, you can consider boring something less the 0.030". I built a "381" (actually a 380.77) with an 0.020" overbore.
Some people have gone absolutely nuts and taken the LT1 block out to an 0.090" overbore, but that takes a careful dimensional analysis of the cylinder wall thickness and concentricity, recentering the bores for optimum thrust wall stength and a bunch of other stuff. It isn't cost effective, and the few cubic inches difference between an 0.020" overbore and an 0.090" overbore are not going to make much difference.
If you bore the cylinders, you need to buy new pistons.
Your current engine is 350ci (actually 349.85). If you were to rebuild it, you might consider keeping the stock crank throw at 3.480", and boring it out wo 4.030". That gives you a 355 (actually 355.12). To get an relative idea of the power potential of each configuration, a rough way to look at it would be simple dividing 383 / 355 and realizing that the 383 gives you about 8% extra displacment, which in rough terms should allow you to make 8% more power, assuming you can supply the extra 8% air with your head and cam selection
01-16-2006, 04:07 PM
#9
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Re: What makes a 383ci??
The torque of a stroker is amazing . My '81 Z28, while "technologically lacking", had tons of grunt, but pulled strong even up top to ~6500 RPM (although ~6200 RPM seemed to be a "sweet spot" 
).
The newer fuellie motors flow so well and work so efficiently, I'd love to make a stroker out of one
... LT1 or LS1 
.
. My '81 Z28, while "technologically lacking", had tons of grunt, but pulled strong even up top to ~6500 RPM (although ~6200 RPM seemed to be a "sweet spot" ).The newer fuellie motors flow so well and work so efficiently, I'd love to make a stroker out of one
... LT1 or LS1 .
01-16-2006, 04:14 PM
#10
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Re: What makes a 383ci??
Originally Posted by Injuneer
and the few cubic inches difference between an 0.020" overbore and an 0.090" overbore are not going to make much difference.
01-19-2006, 01:28 PM
#15
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Re: What makes a 383ci??
So if I have a 4.00" Stoke, a .030 over-bore and 6.0 rods. What Displacement would that give me??
what's the formula so that I can calculate the displacement my self. or if there's a website you can post that too.
Thanks.
what's the formula so that I can calculate the displacement my self. or if there's a website you can post that too.
Thanks.