360/390

Reply Subscribe

Thread Tools

Search this Thread

Jul 16, 2001 | 11:53 PM

arusj

Thread Starter

Freshman User

Joined: Oct 2000

Posts: 35

Likes: 0

360/390

I just bought a '76 to mess with. It has either a 360 or 390, dunno which. The tag on the side of the valve cover is gone. Is there a way to know this by visual assesment? I work mostly on newer engines so this is new for me.

Jul 17, 2001 | 09:07 AM

BobS

Guest

Posts: n/a

360/390

The engine code is the second letter in the VIN (Vehicle ID Number). Y= 360 2 BBL, 8=360 2BBl low compression, H=390 2BBl. Of course the truck is may have any engine in it due to swaps or upgrading.

Bob
'66 7 Litre Convertible, top loader, 3.25 Traction-lock, 427 Sidewinder Intake, 780 Holley, Windage tray, SCJ Exhaust manifolds, H-pipe, MSD, Line-lock, AM/FM/8-Track/CB
'88 F150 XLT Lariat, 302, 5 speed, 3.08
'98 Mustang, 3.8, 5 speed
'99 Ranger, 3.0, 5 speed, 3.73 posi

Jul 17, 2001 | 10:19 AM

Post Fiend

Joined: Feb 2000

Posts: 5,130

Likes: 8

From: Brea CA

360/390

Check out https://www.ford-trucks.com/dcforum/61_79/5832.html

To measure the stroke, get yourself a 1/4" diameter wooden dowel rod about a foot long. Pull the spark plug located by the oil filter and insert the dowel into the hole. Put a socket on the crank bolt and turn the crank until the dowel bottoms out in the hole. Turn the crank back and forth to find the exact bottom. Hold the dowel parallel with the bore and mark it with reference to the top of the spark plug hole. Now turn the crank until the dowel peaks at the top. Turn the crank back and forth again to find the exact top. Hold it parallel and mark it again using the same reference point. Pull out the dowel and measure the distance between the marks, 3.50" is a 360 and 3.78" is a 390. You might get some funny numbers the first time around, it takes a little practice to get it precise.

Barry

Jul 18, 2001 | 09:12 AM

karljay

Cargo Master

Joined: Jul 2000

Posts: 2,281

Likes: 18

From: Northern California

360/390

Another way is to check the back of the crank. The 360 has a half-moon cut in the area where the flywheel bolts on, whereas the 390 would have a square cut in the same spot.

Jul 18, 2001 | 10:34 AM

Post Fiend

Joined: Feb 2000

Posts: 5,130

Likes: 8

From: Brea CA

360/390

https://www.ford-trucks.com/dcforum/User_files/BBB/3b55aa6e42a3a908.jpg

Who’s mooning who?

Here’s the rear end of a '67 truck 352, the 360 looks the same. Been looking for this blurry pic all day, sorry for the poor quality.

Jul 20, 2001 | 01:34 AM

arusj

Thread Starter

Freshman User

Joined: Oct 2000

Posts: 35

Likes: 0

360/390

Thanks everyone. I found out it is a 390 despite the VIN identification. The block was a special green that my dad says indicates a factory rebuild. This may mean it was a 360 and then switched to a 390. The pistons say it on the side. I also found out that it is a C6 which I had hoped.

Jul 21, 2001 | 01:32 AM

FE427TP

Posting Guru

Joined: Oct 1999

Posts: 1,188

Likes: 0

From: yes

360/390

the only way to guarantee it's a 390 is by measuring the stroke, I feel that 390 pistons were used in some 360's to get their low compression ratio...