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351 Cleveland Questions

  • Thread starter Thread starter 302RWP
  • Start date Start date Mar 29, 2004
3

302RWP

New Member
Feb 8, 2004
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Northern California
Mar 29, 2004
#1
  • Mar 29, 2004
  • #1
Need some info on the 351 cleveland as opposed to the 351 windsor. any information would help. Which engine is better? Why? etc. thank you
 
S

slackr

New Member
Feb 10, 2004
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Denver
Mar 30, 2004
#2
  • Mar 30, 2004
  • #2
kind of a broad question..... off the top of my head:
both have the same bore/stroke and bore spacing and use the small block bell housing bolt pattern
the c has a 9.2" deck height as opposed to the w's 9.5"
the c has 8 valve cover bolts, the w 6
the c's water outlet come out of the block, the w's out the intake
the heads can interchange w/some modifications to the water passages
the primary FUNCTIONAL difference is the heads, the c has canted (angled) valves and the valves were bigger than on the w
the c came w/2 common head types, the 4v and the 2v.... ports and valves were bigger on the 4v
better? kind of up to you.... the c's stock had a better head design in my opinion than the w, but the aftermarket for the w seems to be deeper (more availability/choices)
if anyone can add to or correct my info, please do....
 

SadbutTrue

Founding Member
May 1, 2002
2,390
4
49
Granada Hills, California
Mar 30, 2004
#3
  • Mar 30, 2004
  • #3
those differences are pretty good.. the W is slightly lighter and physically smaller as well, mainly because of those heads. Better? Depends on pocketbook.. Stock or near stock, the C is more powerful, because of the heads. It also has rarity and quite a bit more legend behind it. But (though I'm sure some purists would disagree) once you get modern heads (Trick Flow, AFR, etc) on the W, that changes. The W, by most accounts, has a more durable overall design and with the modern heads that the C can't add I think it will eventually take the cake. But either engine is a very good choice.
 

rbohm

Founding Member
Apr 12, 2002
6,698
550
204
tucson,az
Mar 30, 2004
#4
  • Mar 30, 2004
  • #4
both engines are very good at what they were designed for. the 351w has a better oil system than the c does, but the c's oil system can be easily improved as it has only a minor design flaw. the heads, stock for stock are better on the c, but then they were designed for racing as opposed to street use. even the c's 2v heads are very good flow wise. c blocks tend to crack in the main web area when the hp levels are pushed around the 475 mark, unless the block is race prepped. part of the reason is the shorter rod the c uses which puts extra stress on the cylinder walls, and main bearing webs. the w block doesnt crack untill you hit its hp limits, and then it does so rather spectacularly(it tends to split in half lengthwise). both engine blocks cant tolerate 500+hp in race prepped form. as to cranks, when a 351c crank is properly prepped, it can turn 10k rpm with few breakage problems. many forged cranks cant say that. bob glidden figured out how to keep the stock blocks(351c) from cracking. what he did was bore the blocks untill he hit the water jackets, then had .250 thick sleeves furnace welded in. that way he could run an .080 over bore, which when combined with a 3.25 stroke gave him 340ci which dominated the prostosk class to the point that his fairmont in 1978 was undefeated(32-0). for the street and some race action, i would use the 351w. for some street and alot of race action i would use the 351c. but both can be interchanged successfully if you build them right.
 
C

Cantedvalve

Founding Member
Aug 15, 2002
47
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0
Mar 30, 2004
#5
  • Mar 30, 2004
  • #5
302RWP said:
Need some info on the 351 cleveland as opposed to the 351 windsor. any information would help. Which engine is better? Why? etc. thank you
Click to expand...

Ah, the age old debate. Both engines will make power... however, only ONE of them has been largely banned by organized events, and it aint the W. I forget... I think it was Car Craft (or Hot Rod... one of those rags) Fastest Streetcar Shootoout or something like that... they FINALLY let 2V heads in, but 4V PRODUCTION heads are still banned. Dont ask them why, they dont like you pointing that out. Ask me how I know

If I had both laying side by side, I would go with the C. The oiling problems are largely myth, and that myth doesnt start until 7000 RPM by most accounts. There are plenty of parts available for the C, INCLUDING aftermarket aluminum heads that flow up to and over 300 on the intake side. You can spend just as much on a C and get MORE power out of it.

As far as reliability, most of the horror stories are people trying to run pro-stick power through a stock block. Take a stock 1969 351W and you are gonna have to prep the snot out of it as well. The walls are not thin. They have the same thickness walls as the 350 Chevy, and nobody complains there. The oiling system is the same as half the engines out there, and there are simple modifications that can make it better.

Also, keep in mind that the 351W came out FIRST, but then was laregly replaced by the 351C until the gas crunch, in which they went back to the 351W.

Personally, I like a cast iron production heads that will put out 500HP with very little effort... but that's just me.
 
K

kcp203

Founding Member
Mar 27, 2002
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Oak Ridge, NJ
Mar 30, 2004
#6
  • Mar 30, 2004
  • #6
You can usually build a Cleveland for LESS than a W engine. Pick up any parts catalog, and the basic parts (pistons, bearings, valves, etc.) are actually less than those for a Windsor. However, you won't find as wide a selection in either number of vendors or in specifications, ie. compression ratios on pistons or different valve sizes.

The biggest savings though is the fact that you can get 500 hp out of the factory parts. The heads are great, and the stock rods and crank are good up to 8000 rpm if prepped right. No need to spend $ on aftermarket pieces.

The only thing that is fairly expensive is any modification to the rocker pedestals like milling them for adjustable studs. The canted valves makes this a real PITA for the machine shop.
 

brianj5600

Active Member
Sep 19, 2003
1,964
2
39
Middle TN
Mar 30, 2004
#7
  • Mar 30, 2004
  • #7
How much do these heads cost ready to run? They are 30+ years old. By the time you buy them, new valves, springs etc. you have 30+ year old, old tech, heavy cast iron heads. They will make great power, I know that, but the valve size and port size are on the big size for a broad power band. I'm sure you know about the exhaust ports short comings as well. For me, I like aluminum heads designed in the last few years. Cleveland heads can get it done, but if it isn't all out racing, I'll stay with the w's
 

dodgestang

Active Member
Dec 15, 2003
1,360
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37
Cecil County, MD
Mar 30, 2004
#8
  • Mar 30, 2004
  • #8
brianj5600 said:
How much do these heads cost ready to run? They are 30+ years old. By the time you buy them, new valves, springs etc. you have 30+ year old, old tech, heavy cast iron heads. They will make great power, I know that, but the valve size and port size are on the big size for a broad power band. I'm sure you know about the exhaust ports short comings as well. For me, I like aluminum heads designed in the last few years. Cleveland heads can get it done, but if it isn't all out racing, I'll stay with the w's
Click to expand...

Its amazing what happens to 351c heads when you stroke the bottom end to say 408 cubes I put out 400 (394) RWHP through an AOD and 9 inch rear (assuming 20% parasidic loss thats 500 HP at the Flywheel) all with a very mild lope at 10.5:1 compression with the only mod to the heads being screw in studs for my rollers and mild porting on the exhasut side. So it is one extremely streetable racer. Conversely if you stroke out a 351w you have to buy aftermarket heads to get the same level of performance.

I have always been a big fan of both motors and have run both motors in mustangs. Price wise I always say to build what you have. If you have the 351c it will be cheaper to build it and get 400-450 HP out of it than it would be to by a 351w and then build than one. Similarly if you have a 351w it will be cheaper to build it and get 400-450 HP out of it than it would be to buy and build a 351c. The 351w are more plentiful and for the most a small percentage cheaper than comparable 351c parts......but then everything you save you have so spend on new heads

Sure there is a weight savings, there is no arguement there, but in all honesty if you are building a car to see the weigh savings from Iron heads to Aluminum heads on a time slip.....you got deep pockets...and then you can buy the aftermarekt 351c aluminum heads from places like CHI.
 
C

Cantedvalve

Founding Member
Aug 15, 2002
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0
Mar 30, 2004
#9
  • Mar 30, 2004
  • #9
dodgestang said:
Its amazing what happens to 351c heads when you stroke the bottom end to say 408 cubes I put out 400 (394) RWHP through an AOD and 9 inch rear (assuming 20% parasidic loss thats 500 HP at the Flywheel) all with a very mild lope at 10.5:1 compression with the only mod to the heads being screw in studs for my rollers and mild porting on the exhasut side. So it is one extremely streetable racer. Conversely if you stroke out a 351w you have to buy aftermarket heads to get the same level of performance.

I have always been a big fan of both motors and have run both motors in mustangs. Price wise I always say to build what you have. If you have the 351c it will be cheaper to build it and get 400-450 HP out of it than it would be to by a 351w and then build than one. Similarly if you have a 351w it will be cheaper to build it and get 400-450 HP out of it than it would be to buy and build a 351c. The 351w are more plentiful and for the most a small percentage cheaper than comparable 351c parts......but then everything you save you have so spend on new heads

Sure there is a weight savings, there is no arguement there, but in all honesty if you are building a car to see the weigh savings from Iron heads to Aluminum heads on a time slip.....you got deep pockets...and then you can buy the aftermarekt 351c aluminum heads from places like CHI.
Click to expand...

Agreed. I dont think I would swap out a perfectly good 351W for a 351C, but faced with a blown 351W sitting there, I would not hesitate to put it on a chain and get a 351C in there.

Nick, stop rounding those HP numbers up!
 

SadbutTrue

Founding Member
May 1, 2002
2,390
4
49
Granada Hills, California
Mar 30, 2004
#10
  • Mar 30, 2004
  • #10
One other thing to consider is engine bay size... I have a 66 with a 351w, install was easy and all but one of the plugs were easy. We had a 351c ready to install but with a test fit it wasn't going in, not easily anyway. For 67-70 this isn't an issue, but there is some debate as to whether a 351c will work in a 65-66 bay.

but I agree with the others on just about all the other issues. if you buy used aluminum heads for your w (remember you can get ported Twisted Wedge heads ready to bolt on for about 7-800 regularly on ebay) versus just rebuilding some 4v heads for a c, taking into account the slight extra price for c parts and you'll end up spending about the same for a similar performing motor.
 

dodgestang

Active Member
Dec 15, 2003
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37
Cecil County, MD
Mar 30, 2004
#11
  • Mar 30, 2004
  • #11
SadbutTrue said:
We had a 351c ready to install but with a test fit it wasn't going in, not easily anyway. For 67-70 this isn't an issue, but there is some debate as to whether a 351c will work in a 65-66 bay.
Click to expand...

Debate settled:



You need to use 64 falcon (early 65 mustang) style motor mounts (they are a 3 peice set up instead of 2) and headers from www.fordpowertrain.com...its all very close and I but a few bumps in the headers to ensure clearance but all in all a very nice fit. I did absolutely no mods to the shock towers, steering, x-member, or hood. Its all in there, the hood closes and if I had put some quieter exhaust on the car, no one would ever see it coming. It really fills up the engine bay and makes people do a double take when I pop the hood. Changing plugs is actually pretty easy too once you know how...I just pull the valve covers peice of cake
 
6

67GTA-FB429

Member
Dec 15, 2003
777
0
16
Tri-Cities, Wa
Mar 30, 2004
#12
  • Mar 30, 2004
  • #12
Nick; what is the red and black arm that is extending back from the shock tower to the firewall?

do you like the K&N filter? what size is that?
 

dodgestang

Active Member
Dec 15, 2003
1,360
0
37
Cecil County, MD
Mar 30, 2004
#13
  • Mar 30, 2004
  • #13
67GTA-FB429 said:
Nick; what is the red and black arm that is extending back from the shock tower to the firewall?

do you like the K&N filter? what size is that?
Click to expand...

I never cut off the old tabs from the original shock tower braces you can see the red tabs under the black export brace.

The K&N is a 14 inch xtreme flow lid on top of a drop base assembly with a 2.25x14 filter...I actually took the lid off for the time being....the bottom of the lid was just grazing my choke tower and interferring with choke operation so I have a plain pizza pan on there now. I am swapping carbs from a 770vs to an 850dp without a choke tower so I will be putting it back on then.
 
3

302RWP

New Member
Feb 8, 2004
100
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0
Northern California
Mar 30, 2004
#14
  • Mar 30, 2004
  • #14
Thanks for all the information guys, the reason I asked was because my friend is looking to buy a 1969 Mach 1 w/ a 351 Cleveland but he wanted to know how it compares to the Windsor. Thanks again.
 
F

fastcoupe68

Member
Mar 10, 2004
368
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17
nj
Mar 30, 2004
#15
  • Mar 30, 2004
  • #15
Just wanted to clarify something some one in this thread said that a stock 351w block couldnt handle more than 500hp. You are sadly mistaken. I have personnally run built and purchased in crate motor form 351w that make substantially more than 500hp and never had a block failure, as a matter of fact I know of one that made 870hp with forced induction that was run at the track quite often for three years with just preventative maintanance and never had a problem.
 
C

Cantedvalve

Founding Member
Aug 15, 2002
47
0
0
Mar 31, 2004
#16
  • Mar 31, 2004
  • #16
fastcoupe68 said:
Just wanted to clarify something some one in this thread said that a stock 351w block couldnt handle more than 500hp. You are sadly mistaken. I have personnally run built and purchased in crate motor form 351w that make substantially more than 500hp and never had a block failure, as a matter of fact I know of one that made 870hp with forced induction that was run at the track quite often for three years with just preventative maintanance and never had a problem.
Click to expand...

A 870 HP engine in a 351W block with NO prep work?

*gets the waders*
 
G

geegee

Founding Member
Oct 21, 2000
2,015
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near Oklahoma City, OK
Mar 31, 2004
#17
  • Mar 31, 2004
  • #17
If anyone is interested in a 4v Cleveland, I know where there is one ($500). Probably needs rework but is now running in '65 fastback. Owner picked up a built "C" on e-bay auction and it was cheaper than rebuilding his existing "C". Let me know if you're interested (Edmond, OK address).
 
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