The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1967 - 1972 Chevrolet & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 03-05-2017, 03:23 PM   #1
TXBoudy
Registered User
 
TXBoudy's Avatar
 
Join Date: Aug 2016
Location: Southlake, TX
Posts: 181
To pulley or Not to pulley

Hey guys, I'm wondering. I started my serpentine conversion this weekend and to my great irritation, my PS pulley was damaged slightly during removal. Sure it is functionally fine but as mentioned, now I'm irritated. So anyway, I'm upgrading my SB 400 to add the serpentine setup from a '99 engine. My question is now that I have an excuse to purchase new pulleys, is it worth installing a set of under-drive pulleys? I don't want to create any cooling, charging, or any other negative effect on it as it will get driven often.

Thanks ahead for opinions.

Boudy
Attached Images
   
TXBoudy is offline   Reply With Quote
Old 03-05-2017, 03:37 PM   #2
davepl
Registered User
 
davepl's Avatar
 
Join Date: Aug 2006
Location: Redmond, WA
Posts: 6,332
Re: To pulley or Not to pulley

Nah. Do you care if you make another 5 horsepower at max RPM? Unless you're running in a pro-stock class where very hundredth counts, the stock ratios are there to make sure you get adequate charging and power assist at idle, so I wouldn't monkey with it.

Probably only the fan and water pump present any really load, and those can be converted to electric if you really wanted to.

I might be too pessimistic, but I've heard of a number of problems from underdriving and the benefits are very, very small.
__________________
1970 GMC Sierra Grande Custom Camper - Built, not Bought
1969 Pontiac 2+2 427/390 4-speed Coupe
1969 Pontiac 2+2 427/390 4-speed Convertible
davepl is offline   Reply With Quote
Old 03-05-2017, 04:48 PM   #3
El Dorado Jim
Registered User
 
Join Date: Dec 2009
Location: El Dorado Ca
Posts: 3,374
Re: To pulley or Not to pulley

x2
El Dorado Jim is offline   Reply With Quote
Old 03-06-2017, 06:12 PM   #4
TXBoudy
Registered User
 
TXBoudy's Avatar
 
Join Date: Aug 2016
Location: Southlake, TX
Posts: 181
Re: To pulley or Not to pulley

That's pretty much where my head was at, which is why I asked. Thanks for the input.

Boudy
TXBoudy is offline   Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 03:01 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com