C6 high RPM's
Thread Starter
|
Senior User
Joined: Feb 2017
Posts: 100
Likes: 0
C6 high RPM's
Hey guys, just joined the site. This week I purchased a 74 F100 for a restore project. Was told it had a 390 but, after discovering the Y in VIN, I found it's actually a 360 with a 2 bbl. it also has C6 tranny and after taking it out for a ride I noticed the RPM's seem really high at 55 mph. I don't have a tach in it yet so don't know the exact revs. Just sounded really high. Is this normal for a C6?
Postmaster
Joined: Nov 2011
Posts: 2,553
Likes: 10
On the engine... most likely it is a 360 as built. Still, if the engine was ever swapped, it could be a 390. I believe you can check stroke through the spark plug hole to verify... there are many posts on this topic.
Since you can decode the vin you can figure out which rear axle ratio the truck was built with. This will help figure out cruise RPM if it has the original rear end.
Since you can decode the vin you can figure out which rear axle ratio the truck was built with. This will help figure out cruise RPM if it has the original rear end.
Hotshot
Joined: Feb 2004
Posts: 10,760
Likes: 2,590
From: The Shenandoah Valley
Hey guys, just joined the site. This week I purchased a 74 F100 ... etc ... it also has C6 tranny and after taking it out for a ride I noticed the RPM's seem really high at 55 mph. I don't have a tach in it yet so don't know the exact revs. Just sounded really high. Is this normal for a C6?
Yeah, to anyone raised with 4s and 6s and ODs ..... it's gonna sound like it's racing at 70.
Thread
Thread Starter
Forum
Replies
Last Post
2manyprojectsatonce
1967 - 1972 F-100 & Larger F-Series Trucks
19
Dec 7, 2009 06:28 PM
driveline_13
1973 - 1979 F-100 & Larger F-Series Trucks
12
Sep 13, 2008 09:32 AM
thunderguns71
FE & FT Big Block V8 (332, 352, 360, 390, 406, 410, 427, 428)
6
Jan 14, 2005 04:28 PM
