What is the stock S4 Alternator pulley OD
#1
Rotary Enthusiast
Thread Starter
iTrader: (1)
Join Date: Aug 2001
Location: MI 48111
Posts: 982
Likes: 0
Received 0 Likes
on
0 Posts
What is the stock S4 Alternator pulley OD
I'm trying to determine if my S6 swap alternator has an under driven pulley or stock diameter. The problem is I don't have my S4 pulley anywhere so I don't know what diameter it is.
If anyone knows or could take a quick measurement it would be much appreciated. Thanks.
If anyone knows or could take a quick measurement it would be much appreciated. Thanks.
#2
Top Down, Boost Up
iTrader: (7)
I just went through this. The FC alternator pulley is ~45mm in diameter & the FC main pulley is ~90mm. The FD maintains the same ratio (2.08:1 according to S4/S5 FSM) with a ~50mm alternator pulley and ~100mm main pulley. So with an FD alternator on an FC, you'll want to get as close to 45mm as possible to avoid underdriving.
Also, the Atkins double pulley is 54mm in diameter, so it does underdrive a lot on an FC. And the pulleys made by Higgi are apparently about 40mm, which would be slightly overdriving.
Also, the Atkins double pulley is 54mm in diameter, so it does underdrive a lot on an FC. And the pulleys made by Higgi are apparently about 40mm, which would be slightly overdriving.
Thread
Thread Starter
Forum
Replies
Last Post
LunchboxCritter
2nd Generation Specific (1986-1992)
15
01-03-16 04:11 PM
The Shaolin
2nd Generation Specific (1986-1992)
9
09-14-15 07:50 PM