351M / 400 quick question
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Tuned
Joined: Oct 2014
Posts: 306
Likes: 6
351M / 400 quick question
Trying to identify my engine (79 F250) I believe I've narrowed it down to either the 351m or the 400. I say this, because the T Stat housing is on top the intake with vertical bolts.
That said, asumming it to be either engine, are the belts, hoses and ignition parts all the same?
It sounds mean, but this thing is not a race car, that's for sure.
That said, asumming it to be either engine, are the belts, hoses and ignition parts all the same?
It sounds mean, but this thing is not a race car, that's for sure.
Fleet Mechanic
Joined: Jan 2012
Posts: 1,668
Likes: 13
From: Saskatchewan
Trying to identify my engine (79 F250) I believe I've narrowed it down to either the 351m or the 400. I say this, because the T Stat housing is on top the intake with vertical bolts.
That said, asumming it to be either engine, are the belts, hoses and ignition parts all the same?
It sounds mean, but this thing is not a race car, that's for sure.
That said, asumming it to be either engine, are the belts, hoses and ignition parts all the same?
It sounds mean, but this thing is not a race car, that's for sure.
Moderator & parts slinger
Joined: Feb 2007
Posts: 50,150
Likes: 5,783
From: S/W Missouri, Polk county
https://www.ford-trucks.com/forums/1...ml#post1485519
351C/M/400 335 series: 8 bolts in rectangular valve covers. Timing chain housing is part of block. Thermostat housing on block. Exhaust bolt holes diagonal.
351M/400 335 series: intake is 12.7" wide the 351C is narrow. The 351M and 400 are identical externally, only internal parts examination can tell them apart. Or measure the stroke.
351W/302/5.0L 6 bolts on trapezoidal valve covers. Thermostat housing on intake. Exhaust bolt holes horizontal.
429/460 385 series: 7 bolts in rectangular valve cover
352/360/390/427/428 FE series: Intake goes under valve covers.
351C/M/400 335 series: 8 bolts in rectangular valve covers. Timing chain housing is part of block. Thermostat housing on block. Exhaust bolt holes diagonal.
351M/400 335 series: intake is 12.7" wide the 351C is narrow. The 351M and 400 are identical externally, only internal parts examination can tell them apart. Or measure the stroke.
351W/302/5.0L 6 bolts on trapezoidal valve covers. Thermostat housing on intake. Exhaust bolt holes horizontal.
429/460 385 series: 7 bolts in rectangular valve cover
352/360/390/427/428 FE series: Intake goes under valve covers.
Cargo Master
Joined: Nov 2011
Posts: 3,354
Likes: 48
From: Great American SouthWest
Doesn't seem common, but occasionally a dealer would do an engine swap for a customer. What does your VIN say? J is 460, S is 400 and H is 351
If the engine has been swapped, the VIN remains the same, so the VIN is not the final word-just a starting point
If the engine has been swapped, the VIN remains the same, so the VIN is not the final word-just a starting point
Ford Parts Specialist
Joined: Nov 2006
Posts: 88,826
Likes: 784
From: Simi Valley, CA
Trying to identify my engine (79 F250) I believe I've narrowed it down to either the 351m or the 400. I say this, because the T Stat housing is on top the intake with vertical bolts.
That said, asumming it to be either engine, are the belts, hoses and ignition parts all the same?
That said, asumming it to be either engine, are the belts, hoses and ignition parts all the same?
351C/351M/400: There is no timing cover per se, just a flat engine cover plate. The fuel pump bolts to the left side of the engine block in a 6 & 12 o'clock pattern.
4th digit of the VIN is the engine code: H = 351M / S = 400. But this only holds true if the engine is the original.
To determine the engine size, measure the stroke. 351M = 3.50" / 400 = 4.00."
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Tuned
Joined: Oct 2014
Posts: 306
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Yeah, I'd read about removing the #1 plug and measuring tdc, piston travel, something of the sorts.
4th character is a J on vin, which matches the owners info. But the 469 has the water outlet on the front of the block?
Not trying to make another identification thread. I'll have to go back and read the previous ones. I thought the 460 had 7 bolt valve covers though, but the water outlet was bolted horizontal.
4th character is a J on vin, which matches the owners info. But the 469 has the water outlet on the front of the block?
Not trying to make another identification thread. I'll have to go back and read the previous ones. I thought the 460 had 7 bolt valve covers though, but the water outlet was bolted horizontal.
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Tuned
Joined: Jan 2017
Posts: 338
Likes: 8
From: North Idaho
I've performed the stroke test and believe it's the easiest way to tell a 351 from a 400. While it takes two people (or a starter solenoid switch trigger) and a small dowel, it's as simple as:
- removing a spark plug and the coil wire
- "bumping" the engine until the removed-plug cylinder piston is top dead center
- marking your dowel
- bumping the engine until the removed-plug cylinder piston bottoms out, then
- mark the dowel and measure the difference / distance of your stroke.
Just make sure that your dowel is plenty long so you don't drop it into the cylinder
Also, a 460 looks completely different. The valve covers almost have a straight-vertical look to them. Hope this helps...
- removing a spark plug and the coil wire
- "bumping" the engine until the removed-plug cylinder piston is top dead center
- marking your dowel
- bumping the engine until the removed-plug cylinder piston bottoms out, then
- mark the dowel and measure the difference / distance of your stroke.
Just make sure that your dowel is plenty long so you don't drop it into the cylinder
Also, a 460 looks completely different. The valve covers almost have a straight-vertical look to them. Hope this helps...
Cargo Master
Joined: Nov 2011
Posts: 3,354
Likes: 48
From: Great American SouthWest
The 360/390 has the water neck on the front of the block
On the 460, the thermostat housing bolts to the intake manifold
also, the dipstick for 2wd 460 is in the timing cover, and is annoyingly close to the heater hoses
congratulations, my friend-you have a 460!
On the 460, the thermostat housing bolts to the intake manifold
also, the dipstick for 2wd 460 is in the timing cover, and is annoyingly close to the heater hoses
congratulations, my friend-you have a 460!
Senior User
Joined: Oct 2016
Posts: 401
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From: Rockville, IN Temporarily
Yeah, I'd read about removing the #1 plug and measuring tdc, piston travel, something of the sorts.
4th character is a J on vin, which matches the owners info. But the 469 has the water outlet on the front of the block?
Not trying to make another identification thread. I'll have to go back and read the previous ones. I thought the 460 had 7 bolt valve covers though, but the water outlet was bolted horizontal.
4th character is a J on vin, which matches the owners info. But the 469 has the water outlet on the front of the block?
Not trying to make another identification thread. I'll have to go back and read the previous ones. I thought the 460 had 7 bolt valve covers though, but the water outlet was bolted horizontal.
Photos are of a 460. Thermostat housing is on the intake manifold.
Thread Starter
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Tuned
Joined: Oct 2014
Posts: 306
Likes: 6
Well, the 351M and 400's didn't seem to have much horse power, hadn't even looked at that of the 460. Not sure which powerplant is the most desirable.
This is just a fun truck, no daily driver. So gas mileage doesn't mean anything.
Thanks for all your help guys!
This is just a fun truck, no daily driver. So gas mileage doesn't mean anything.
Thanks for all your help guys!
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Racetruckin
335 Series- 5.8/351M, 6.6/400, 351 Cleveland
9
Oct 4, 2004 02:33 AM
Blueoval_racing
335 Series- 5.8/351M, 6.6/400, 351 Cleveland
2
Jul 17, 2004 08:30 AM