Notices
GM Engine & Exhaust Performance EFI | GEN I/GEN II/GEN III/GEN IV Engines |Small Block | Big Block |

will running a smaller crank pulley have any effect on S/C boost?

Thread Tools
 
Search this Thread
 
Old 05-05-2004, 05:10 PM
  #1  
what a rush!
Thread Starter
iTrader: (8)
 
moregrip's Avatar
 
Join Date: Feb 2004
Location: Las Vegas, NV
Posts: 17,610
Received 28 Likes on 20 Posts
Default will running a smaller crank pulley have any effect on S/C boost?

lets say someone had a radix designed to run at 6-7psi boost

would running a smaller crank pulley increase said boost?
Old 05-05-2004, 05:15 PM
  #2  
TECH Fanatic
iTrader: (23)
 
TwoFast's Avatar
 
Join Date: Jul 2003
Location: Mesquite, TX
Posts: 1,331
Likes: 0
Received 0 Likes on 0 Posts
Default

You will loose boost. Hopefully Blownchevy can chime in soon. He can tell you all about it.
Old 05-05-2004, 05:21 PM
  #3  
what a rush!
Thread Starter
iTrader: (8)
 
moregrip's Avatar
 
Join Date: Feb 2004
Location: Las Vegas, NV
Posts: 17,610
Received 28 Likes on 20 Posts
Default

now that I think about it more I think that is correct

my analogy is this:
on a motorcycle if you want to have lower overall gear selections without going into the tranny you have two options......install a smaller front sprocket(i.e. blower pulley) or a larger rear sprocket (i.e. crank pulley)

makes perfect sense know! what was I thinking?
Old 05-05-2004, 05:25 PM
  #4  
blownerator
iTrader: (20)
 
BlownChevy's Avatar
 
Join Date: Mar 1986
Location: Chatsworth, CA
Posts: 18,745
Likes: 0
Received 7 Likes on 7 Posts
Default

Chime!

Smaller pulley, less boost. Bigger Pulley more boost!
Old 05-05-2004, 05:25 PM
  #5  
TECH Fanatic
iTrader: (1)
 
Deckhand's Avatar
 
Join Date: Apr 2003
Location: Corpus Christi, TX
Posts: 1,887
Likes: 0
Received 1 Like on 1 Post
Default

Originally Posted by moregrip
now that I think about it more I think that is correct

my analogy is this:
on a motorcycle if you want to have lower overall gear selections without going into the tranny you have two options......install a smaller front sprocket(i.e. blower pulley) or a larger rear sprocket (i.e. crank pulley)

makes perfect sense know! what was I thinking?
must be those women!
Old 05-05-2004, 05:27 PM
  #6  
Launching!
 
yeary03SS's Avatar
 
Join Date: Oct 2003
Location: Little Rock, AR
Posts: 285
Likes: 0
Received 0 Likes on 0 Posts
Default

This may sound strange, but you'll have to have a bigger crank pulley to increase boost. The crankshaft will always spin at the same rotational speed. On two pulleys connected by a belt, the angular velocity times the radius of one pulley must equal the angular velocity times the radius of the second one. Thus keeping the same angular velocity on the crank and using a bigger radius makes the angular velocity increase on the unchanged radius on the supercharger pulley. Going to a smaller pulley on the supercharger itself will also increase boost.
Old 05-05-2004, 06:02 PM
  #7  
blownerator
iTrader: (20)
 
BlownChevy's Avatar
 
Join Date: Mar 1986
Location: Chatsworth, CA
Posts: 18,745
Likes: 0
Received 7 Likes on 7 Posts
Default

Originally Posted by yeary01z71
This may sound strange, but you'll have to have a bigger crank pulley to increase boost. The crankshaft will always spin at the same rotational speed. On two pulleys connected by a belt, the angular velocity times the radius of one pulley must equal the angular velocity times the radius of the second one. Thus keeping the same angular velocity on the crank and using a bigger radius makes the angular velocity increase on the unchanged radius on the supercharger pulley. Going to a smaller pulley on the supercharger itself will also increase boost.

Uhhhhh, uhhhhhh huh huhuhuhuhhh he said bigger radius.
Old 05-06-2004, 06:04 AM
  #8  
Launching!
 
yeary03SS's Avatar
 
Join Date: Oct 2003
Location: Little Rock, AR
Posts: 285
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by BlownChevy
Uhhhhh, uhhhhhh huh huhuhuhuhhh he said bigger radius.
yeah, yeah, bigger radius (that was my attempt at Beavis)
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
stealthperf
General Truck Racing and Discussion
34
02-14-2016 11:35 AM
TAPyvehc93
FORCED INDUCTION
6
08-21-2015 05:19 AM
bigsapper
GMT K2xx Trucks General Discussion
7
07-28-2015 12:56 AM
blownss27
GM Parts Classifieds
10
07-20-2015 08:59 AM
bsn1989
GM Drivetrain & Suspension
0
07-16-2015 08:20 AM



Quick Reply: will running a smaller crank pulley have any effect on S/C boost?



All times are GMT -5. The time now is 07:51 PM.