supercharged SBC's
08-13-2002, 08:28 PM
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supercharged SBC's
Blew a motor this weekend and I am going to repower with blower small blocks.I am considering 383's.Does anybody have any experience in this setup.I plan on using 871 blowers.
Fishead
Fishead
08-13-2002, 11:03 PM
#4
BEACH PARTY
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Vortec is now making a killer blow-thru carb setup that would be sweet on a 383 (in fact, either Hot Rod or Car Craft had a buildup or two within the last month). The carb is also completely sealed by the new blower box which will make life really easy.
You also don't have to worry about what to do with those blowers in terms of height.
You also don't have to worry about what to do with those blowers in terms of height.
08-14-2002, 08:20 AM
#5
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Hot Rod magazine has a similar article on the Vortech carb blower.
Looks like the perfect set-up.
They tested it on a GM HT383 crate motor that was modified with a Edelbrock RPM Air Gap, 750 Speed Demon carb, Comp Cams XE282HR cam, 1.6:1 rockers, 9.1:1 compression, Vortech heads (I think). Without the blower this combination made 476HP@5500 and 505 lb-ft@4400.
First run with the blower had a 6" crank pully and a 3.47" blower pully pumped out 3lbs of boost for an almost 100HP gain.
Swapped the blower pully for a 3.125" and got 7lbs boost and 643HP@6000 with 600lb-ft from 3500 to 5500 and max was 606lb-ft@4900.
Swapped blower pully again to a 2.95", got 8lbs boost and 677HP and 627lb-ft@5000.
Looks like the perfect set-up.
They tested it on a GM HT383 crate motor that was modified with a Edelbrock RPM Air Gap, 750 Speed Demon carb, Comp Cams XE282HR cam, 1.6:1 rockers, 9.1:1 compression, Vortech heads (I think). Without the blower this combination made 476HP@5500 and 505 lb-ft@4400.
First run with the blower had a 6" crank pully and a 3.47" blower pully pumped out 3lbs of boost for an almost 100HP gain.
Swapped the blower pully for a 3.125" and got 7lbs boost and 643HP@6000 with 600lb-ft from 3500 to 5500 and max was 606lb-ft@4900.
Swapped blower pully again to a 2.95", got 8lbs boost and 677HP and 627lb-ft@5000.
08-15-2002, 10:03 AM
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Dave F,
The reason for the 871 is that it will turn slower and not make as much heat as a smaller one that would need to turn faster.
Dixie Doug,
Why do you say forget about it?
Fishead
The reason for the 871 is that it will turn slower and not make as much heat as a smaller one that would need to turn faster.
Dixie Doug,
Why do you say forget about it?
Fishead
08-15-2002, 12:07 PM
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What drives are you running? If they're alphas, FORGETABOUTIT.
A mildly warmed up 330 would probably go faster for a lot less money. But if you want that blower look a 177 or 256 would be more than adequate to feed a SBC at around 5psi without turning too fast.
my $0.02
Gary
A mildly warmed up 330 would probably go faster for a lot less money. But if you want that blower look a 177 or 256 would be more than adequate to feed a SBC at around 5psi without turning too fast.
my $0.02
Gary
08-15-2002, 03:31 PM
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I guess that answered my questions.
You might just consder a well built 350 with blower pistons. It's easier/cheaper to put together than a 383 and a little extra boost will make up for the torque. If you could use many of your current parts, you could do it very economically. If you have to replace the existing crank, rods, & pistons, then you'll only need a new flywheel, so a 383 might not be a bad idea.
A cast crank, good rods/bolts, blower pistons (8:1?), heavy duty valves, and a 177 (same blower used on BBC 525SC) at 5-7 lbs might make a reliable engine.
My $0.02,
Note, I've had a couple 525SCs but never put together a SBC blower motor, so my input may not be worth $0.02.
BTW are you running Twin Disc 502 trannys with the Kaamas?
Gary
You might just consder a well built 350 with blower pistons. It's easier/cheaper to put together than a 383 and a little extra boost will make up for the torque. If you could use many of your current parts, you could do it very economically. If you have to replace the existing crank, rods, & pistons, then you'll only need a new flywheel, so a 383 might not be a bad idea.
A cast crank, good rods/bolts, blower pistons (8:1?), heavy duty valves, and a 177 (same blower used on BBC 525SC) at 5-7 lbs might make a reliable engine.
My $0.02,
Note, I've had a couple 525SCs but never put together a SBC blower motor, so my input may not be worth $0.02.
BTW are you running Twin Disc 502 trannys with the Kaamas?
Gary
