72 Mach 1 Q code cobra jet !

[wolfawaken]

Welcome, when you are finished it will look amazing, the group will be cheering you every step of the way.

 

[Sheriff41]

Welcome from Texas!

 

[mach71351c]

Welcome from San Diego

 

[PoFoMoCo]

Welcome from West Texas, you're definitely in the right place!

 

[Bill Perkins]

Welcome from Opelika, Alabama

 

[71ProjectJunk]

Welcome from Texas!

 

[Graham Man]

1971 351M code is almost the same engine, well smaller carburator (600cfm) so 5hp less, put the CJ intake and the 750 cfm spread bore carb... bet it makes 300+hp. The M gets a bad rep from the later year M code.

 

[Stanglover]

1971 351M code is almost the same engine, well smaller carburator (600cfm) so 5hp less, put the CJ intake and the 750 cfm spread bore carb... bet it makes 300+hp. The M gets a bad rep from the later year M code.

?

 

[Retired2014]

Let the games begin...step 1 complete, car dropped off.
PS-don't leave those tires on the front when the car is completed/restored

+1 on the front tires!

 

[NOT A T5]

Welcome from Omaha!

 

[YellowHorse]

1971 351M code is almost the same engine, well smaller carburator (600cfm) so 5hp less, put the CJ intake and the 750 cfm spread bore carb... bet it makes 300+hp. The M gets a bad rep from the later year M code.

71 351-4v M code actualy has more HP then Q code because it has higher compression. Same exact engine as 70 M code (Ford just had to correct compression and HP numbers because they were over hyped for 70). Some say HP deccese fro 70 to 71 was due to insurance, but compression part - Ford got it very wrong for 70.

Q code is actualy downgraded M code (after May 1971), but hyped it up as something better - adding CJ title.
Ford put in larger carb and a bit higher lift cam to offset some of the power loss due to lower compression when they went to emission friendly open chamber heads.
Intake manifolds are same, other then carb plate.

OP - if you find M code engine instead of Q - go for it, more power with same modifications. Can always throw CJ manifold and carb and good aftermarket cam, if you want to look stock. But better off with aftermarket carb and manifold (oem 3400D carb was not relaible or good for drivability)

 

[Phantom Kat]

Welcome from a fellow 72 Q code member. What tranny is in your car? Post a few photos when you get a chance.

Currently has a c6 auto behind the 429

 

[Stanglover]

Engines aren't my strong point (if I have one), but if you're still looking for a 351C block, early 70 blocks had the oil drain holes at the back of the motor. I had a "J" block D0AE-J but sold it because I thought the rear drain holes were a bad idea. These block, according to my info were all 2 bolt, BUT any Cleveland block can be drilled and tapped for 4 bolts....... if you can find the caps. Next step "L" blocks had a crude hole at the front of the block cast in for oil drainage and back holes eliminated. Blocks with casting codes D0AE-B,D,F,H were 4 bolt( apparently)
A pretty good source of information can be found at http://www.mustangtek.com. Other websites can be found on Google http://www.castingnumbers.info/site/browse/m/ford/p/3 is another.
Basically, any Cleveland block will work for a non matching number car, it's the add-ons that make the difference.

 

[YellowHorse]

Engines aren't my strong point (if I have one), but if you're still looking for a 351C block, early 70 blocks had the oil drain holes at the back of the motor. I had a "J" block D0AE-J but sold it because I thought the rear drain holes were a bad idea. These block, according to my info were all 2 bolt, BUT any Cleveland block can be drilled and tapped for 4 bolts....... if you can find the caps. Next step "L" blocks had a crude hole at the front of the block cast in for oil drainage and back holes eliminated. Blocks with casting codes D0AE-B,D,F,H were 4 bolt( apparently)
A pretty good source of information can be found at http://www.mustangtek.com. Other websites can be found on Google http://www.castingnumbers.info/site/browse/m/ford/p/3 is another.
Basically, any Cleveland block will work for a non matching number car, it's the add-ons that make the difference.

There is no reason to drill and tap for 4 bolt mains unless you are looking to go past 500whp or rev constantly to 9k rpms. Rods and cylinder walls are the the weak point when you push motor for more power and rpms, not mains.

Non of the Clevelands have oiling issues. Issue is inadequate oil capacity for the car use. Boss ran 6qt instead of 5qt using same capacity oil pan (oil pan has extra windage tray, but you can buy aftermarket bolt on windage tray). And of course dont run thick oil if you live in the hight rpms, to make sure oil makes back to oil pan in time (assuming oil you chose does not brake down at elevated temperatures - like QS 5w30, performs well at 270 deg compared to any other 30 or 40 weight oils).

 

[Stanglover]

There is no reason to drill and tap for 4 bolt mains unless you are looking to go past 500whp or rev constantly to 9k rpms. Rods and cylinder walls are the the weak point when you push motor for more power and rpms, not mains.

Non of the Clevelands have oiling issues. Issue is inadequate oil capacity for the car use. Boss ran 6qt instead of 5qt using same capacity oil pan (oil pan has extra windage tray, but you can buy aftermarket bolt on windage tray). And of course dont run thick oil if you live in the hight rpms, to make sure oil makes back to oil pan in time (assuming oil you chose does not brake down at elevated temperatures - like QS 5w30, performs well at 270 deg compared to any other 30 or 40 weight oils).

I agree on 4 bolts. The extra bolts do nothing for cap strength, but were thought to prevent fretting, sideways movement. Been discussed many times.
Oil; agree again, but that subject has been hashed and bashed many times also.
I was merely referring to a design change Ford made because obviously, someone decided the rear holes were not the best option. Personally, I wish I'd kept that "J" block to build a spare motor. That was the intent when I bought it for $100 cdn.

 

[Steed73]

71 351-4v M code actualy has more HP then Q code because it has higher compression. Same exact engine as 70 M code (Ford just had to correct compression and HP numbers because they were over hyped for 70). Some say HP deccese fro 70 to 71 was due to insurance, but compression part - Ford got it very wrong for 70.

Q code is actualy downgraded M code (after May 1971), but hyped it up as something better - adding CJ title.
Ford put in larger carb and a bit higher lift cam to offset some of the power loss due to lower compression when they went to emission friendly open chamber heads.
Intake manifolds are same, other then carb plate.

OP - if you find M code engine instead of Q - go for it, more power with same modifications. Can always throw CJ manifold and carb and good aftermarket cam, if you want to look stock. But better off with aftermarket carb and manifold (oem 3400D carb was not relaible or good for drivability)

Ford rated both as having the same horsepower even though the closed chamber had more compression. The closed chamber also had more emissions and a lot of unused fuel went out the exhaust. The open chamber design had much more complete combustion and a cleaner burn. I still prefer the open chamber design for that reason. Also, it was not difficult to increase the compression during a rebuild. An increase from 8:1 to 10.5:1 added huge horsepower.

 

[Cleveland Crush]

Ford rated both as having the same horsepower even though the closed chamber had more compression. The closed chamber also had more emissions and a lot of unused fuel went out the exhaust. The open chamber design had much more complete combustion and a cleaner burn. I still prefer the open chamber design for that reason. Also, it was not difficult to increase the compression during a rebuild. An increase from 8:1 to 10.5:1 added huge horsepower.

Many racers preferred the Cleveland open chamber heads and actually considered them a "semi-hemi" design. As Steed73 mentioned, the open chamber heads are very potent performers.

 

[YellowHorse]

Many racers preferred the Cleveland open chamber heads and actually considered them a "semi-hemi" design. As Steed73 mentioned, the open chamber heads are very potent performers.

Probably depends on what you build. Force induction and nitrous definitely open heads and low compression.

OC need domed / poped pistons to achieve good dynamic comp ratio (get it to mid 7s) for all out NA motor.

They both have positives, jut takes more to make Q to reach full potential.