Need Recommendations on 351C Rebuild

There are a few paths to follow when it comes to modifying the 351C 4V. Keep in mind this motor was designed as a race motor and then detuned for passenger car use. The 4V heads are 500 BHP endurance racing heads, and their potential goes way beyond 500 BHP. When it comes to camshafts with about 0.600" lift the 40 year old Cleveland head can still hold its own against modern rivals. A very solid street motor can be built around the iron 4V heads.

However, the "detuned race motor" power characteristic of the 351C 4V is not everybody's cup of tea. If that's the case with you a good recommendation for drivability, throttle response, and about 400 BHP at the same time is a set of alloy 2V heads, the Edelbrock Air Gap intake, a Holley #0-82751 750 cfm HP carburetor, and a flat tappet hydraulic camshaft with 224 to 230 degrees intake duration (at 0.050" lift) and about 0.550" to 0.600 inch lift. If your motor still has the factory exhaust a replacement exhaust will be called for as well. The GTS exhaust is a cost effective, quiet, easy to install bolt-on option, but there are other ways to go as well. Dan Jones has found the GTS mufflers rob about 50 BHP from the motor, but the advantage is they are quieter than any other option.

I would recommend the Trick Flow, AFD or CHI heads over the Edelbrock heads simply because they flow better out of the box. Trick Flow is supposed to begin shipping their heads very soon. The pricing of the Australian heads has been creeping upward because the value of the US dollar has weakened against foreign currency. Lunati is always a good recommendation for Ford camshafts, the Lunati company understands Fords and upgrades their Ford camshafts more frequently than any other camshaft company. They also produce a quality product. One good recommendation would be Lunati's Street Master #07111 hydraulic flat tappet camshaft. The cam specs are 225/225 degrees duration at 0.050”, 275/275 degrees advertised duration, 0.550”/0.550” lift and 108 degrees LCSA. The cam idle characteristic is advertised as "good" but you can expect that to mean a little lopey, but the Cobra Jet cam idles a little lopey too. Its power band is advertised at 1800 to 5800 RPM. This cam has both muscle and manners. You can fry tires all day long with this camshaft.

Other items:
Remove & inspect the fuel tank while the motor is pulled. Replace all fuel hoses. Replace or rebuild the harmonic dampener. Good time to at least inspect the cooling system tubes & hoses. If the car hasn't been upgraded with an electronic ignition, this is the time to do it. Now is also the time to install an Armando #404, Kevko #F602-400M or Aviaid #155-55365 oil pan.

Thank you for the very detailed response. My car is a Pre-L '72 and still has what I believe the stock setup along with factory air cleaner, etc. The has been upgraded with a big bore exhaust as well as having new cooling tubes in as well. Sounds crazy, but I'm not sure on the ignition or on the fuel tank but will look at both issues while I'm in there.

A few more questions if you don't mind - First, are the oil pans you mention larger and, if so, will they fit without having to cut the lower cross member? Second, would now be a good time to have the engine bored for a "stroker" motor and do I sacrifice longevity or reliability if this is done? (Recommendations 383, 396, etc?) Third, on the cam - when you say lopey, are you referring to the the cycle of the cam or how hard it hits at idle? I may not be asking this the right way. Also do I need to be mindful if I am getting a solid or hydraulic version?

Thanks again for any input. I've got to get with my guy next week and discuss how we are going to proceed.

If your cleaning the gas tank and changing the hoses now might be a good time to upgrade the fuel line to 1/2".
Mark
5481 & 5461

...if You go with a larger sump oil pan, such as the Moroso '10 Quart', they are much wider than the Stock Pan; Be ready to cut off the Bracket for the 'Emergency/Parking Brake'!! So as to clear rhe side rails when You reinstall the Engine. It was at this point (Engine allmost on it's mounts) that I found the Bracket (OR the Pan) had to go! I sawwed Off the Bracket!! Did Not make much difference to Me. After installing larger Willwood Brakes in the Rear, there were NO E. Brake Calipers, anyway! Good-Luck with Your rebuild!...

quote:

Be ready to cut off the Bracket for the 'Emergency/Parking Brake'!!

I suspect Marlin used the wide sump version, and with that style, yes, you need to modify something.

If you want to retain the emergency brake system, stay with a Pantera-specific deep sump version.

If you use the Armando pan, 10 quart, no modifications are needed. It is a good idea to upgrade to a removable crossmember, though, so the pan can be removed (in theory) with the engine still in the car.

Larry

Yup. Get an oil pan made for a Pantera and not a Mustang. Yikes Marlin? Comon?

You can go a little more on cam. 236 @ .050 won't hurt. No more the 72 degrees of overlap.

Unfortunately though the C is one of the most sensitive engines I've ever seen, to compression ration and gas octane. If you keep it under 10.5:1 you should be ok.

If you go too much under that, the engine is a dog. Slugish. If you go over it is an animal but you will need leaded racing gas. None of this unleaded crap.

It really is too bad that this engine likes 11.5:1 so much. Likes is an understatement. It loves it, but you would need old Sunoco 260 to run it.

As it is, you need to run the stock heavy distributor advance springs to slow the advance curve.

Also be aware that there are almost no intake manifolds that will fit under the stock screen. The Blue Thunder Pantera manifold is nice but it is a big port.

As George says, 400hp is easy. 500 is right there if you want to put up with a little BS now and then?

I've changed intakes and the Weiand intakes, and most of the Edelbrock intakes will fit with a Holley carb and stock air cleaner under the stock screen. This will continue to give you the clean look (stock) you are probably looking for.

quote:

Originally posted by inhotwatter:
... are the oil pans you mention larger and, if so, will they fit without having to cut the lower cross member?

Larry's picture is worth a 1000 words. You don't have to cut the crossmember as long as you install the oil pan while the engine is out of the car.

quote:

Originally posted by inhotwatter:
... would now be a good time to have the engine bored for a "stroker" motor and do I sacrifice longevity or reliability if this is done ...

The Cleveland is capable of making plenty of horsepower if you spin the motor at high enough rpm (use a bigger cam), stroker kits lower the engine speed at which that additional horsepower is made, approximately 400 rpm lower for every 25 cubic inches (0.25" increase in stroke = 25 cubic inches). If approximately 400 horsepower at 6000 rpm is enough horsepower, then I don't see a need for a stroker kit.

Reliability will not be sacrificed by a stroker kit as long as no short cuts are taken. Also, if a red line of 6000 rpm is used, the engine is so under-stressed at that engine speed that block cracking or lubrication will not be issues. However the oem iron crank is easier on the block than a steel crank, and the oil passages in the oem crank compliment the design of the lubrication system best.

quote:

Originally posted by inhotwatter:
... on the cam - when you say lopey, are you referring to the the cycle of the cam or how hard it hits at idle ...

Lopey means a slightly rough or uneven idle. Lopey is between a smooth idle and a rough race car type idle. You can smooth a lopey idle out by adjusting the motor to idle at a higher rpm.

quote:

Originally posted by inhotwatter:
... do I need to be mindful if I am getting a solid or hydraulic version ...

The cam I recommended is a hydraulic flat tappet camshaft. No adjusting necessary. You'll have to be mindful to use motor oil known for containing generous amounts of ZDDP, not an issue.

Ok - thanks again for the detailed info. The engine is now out and it looks like the block is bad so my question is this - now what? Should I go back with a used 351C block (my first thought) or swap over to a 351W or some other setup? Please keep in mind that I am in TN and not in Pantera Central in Southern CA. While my mechanic is good, he doesn't have the experience with these cars like the Pantera dedicated shops have. I'm guessing that the 351C is probably the most straight forward approach since that is what came out, but I would like some opinions from those of you who have been around these beasts for a while. Thanks again.

I'm already going through withdrawal and it's only been out of my garage for 3-weeks.

I would stay with a Cleveland. If you don't want to build it yourself you can buy one from any of the Pantera vendors.

Since your block is bad, here is a solution that may help. Contact Chris in Phoenix about his 393 stroker short block ( all new including cam and roller lifters) at 480-330-5549. He is asking $2900 and has receipts and all the new parts and gaskets. I am also building a cleveland, but decided to go with a 408 stroker motor instead of the 393, since the engine builer I'm using is a "Ford" specialsist and close by. Good luck on your project.

quote:

I would stay with a Cleveland.

Ditto.

why reinvent the wheel?

Larry

P.S. - Block is bad? Exactly why?

Hi stay w/ the 351C motor, since as you state you dont live in Pantera world (S.Calif) and live in the near back woods stay with the 351, you can do mild things to make it run like a bat out of hell, some head work, potra plates, heavier springs, good cam, I use thge edelbrock mani which works better than the Blue thunder that was used several years back and for god sakes get rid of that carter & go w/ a Holley or demon carb,
my 2 cts Mike # 7042

Thanks for the advice - the 351C it will be. I figured that was the best route, but thought it was worth asking.

What happened? Exhaust spring broke which eventually led to the valve bottoming and .... thus damaging the head and ultimately led to the block being damaged as well.

Just time I guess as I was only idling away from a traffic light under very low RPMs and then lost power and heard metal to metal - not a good sound.

Also think about if it was 1 of the newer alumn head and it over heats or drops a valve you would be replacing the complete heads instead of fix the old cast iron baot anchors- the old heads will take a major amount of abuse not like the alumn heads of todays market
my 2 cts again
Mike #7042

[QUOTE]Originally posted by inhotwatter:

What happened? Exhaust spring broke which eventually led to the valve bottoming and .... thus damaging the head and ultimately led to the block being damaged as well.
QUOTE]

If the block hasn't been bored already why don't you just sleeve it?

Sorry for the delay in response. I'm not an engine guy, but was told that sleeving it was not a great fix - was told that going that route would be a weak spot in the engine and that I might as well fix it right while I was there.

I have to disagree especially if your trying to keep the original-matching #'s block, if the sleeve is done correctly then you get a new surface to work with and that area will be stronger now -with the new technology & materials- at least that what a few hi-rep engine buuilders say here in S. Calif
my 2 cts
Mike #7042

I've seen racers sleeve all eight cylinders on new blocks as preventative measures.

Not only are the thrust surfaces of the cylinder thicker with the sleeves, the block is more rigid.

Sleeve the block. It is much stronger then original.

I recall reading something about only sleeving a maximum 2 cylinders on a Cleveland, not sure why that would be?

Julian

I personally wouldn't want to do the machining on an entire block and it probably has to do with spacing and cylinder thicknesses.

For sure one sleeve can't be any kind of a problem?

It's a while since I saw the 8 sleeves and it might have been a 427 Ford block. Can't remember specifically now.

You need to remember that the word insane can't always be used with certain people.

Sometimes you need to be crazy to be brilliant? Matter of fact, aren't those words synonyms for each other?

Sleeving may have worked flawlessly; however, we went ahead and located a replacement 351C block. I'll keep the old block just in case someone wants a matching numbers car if I ever sell mine. Matching numbers wasn't too big of a deal for me - especially on the Pantera as it doesn't seem to matter in the end to most buyers. In the future, I might sleeve or even go with a 351W, but for now I'm sticking with the 351C.

I do have another question on water pumps & ignition systems. Is it worth the extra money to go back with a new high flow aluminum water pump vs. a rebuilt steel replacement ($250 vs. $50). My understanding is that they are not only lighter, but also flow more water and dissipate heat faster? Is this a good upgrade for the extra $200?

On the ignition front - I'm looking to go to one of the newer electronic ignition systems vs. the factory Duraspark. Any reason why this wouldn't be a good upgrade as well?

Sorry - somehow missed the post on the water pump discussion going on right now. My car has the stock radiator with an extra manual fan & no hood vents. To upgrade the water pump or not is the question?

http://pantera.infopop.cc/eve/...50045562&m=319102053

above is a link to a forum discussion on swapping TO a Duraspark...there might be some info there that would help you decide on the ignition swap. I going from the stock dual point stock system out of my 72L to the Duraspark. There are a number of advantages plus ease of finding parts pretty much anywhere in the US.

On sleeving a 351-C: the weakest part of a Cleveland block is the cylinder walls, and the next weakest is the heavily sculpted area just above the main bearing mounts. Wet-sleeving cuts a notch in exactly that area at the base of the sleeve just above the main supports, which is also press-fitted into it. Both operations weaken the entire block support. By only doing one cylinder per bank, blocks seem to not fail the crank supports. More than one sleeve per side does sometimes fail the block.

On the water pump discussion: the theoretical higher efficiency of a curved-vane vs a straight-vane pump has never shown up where its needed- by lowering the stabilized temperature of your coolant. So I take the $200 for the fancy pumps, buy a $79 aluminum Weiand 8209- which is half the weight of the cast iron ones, and drive on down the road. I now have 19 years and 50,000 miles on my Weiand.... note it does NOT have the stock warm-up bypass port so any old thermostat will also fit. But changing to a lower range thermostat won't lower your operating temp, either.

On the Duraspark conversion: I was one of the last hold-outs for points until 5 years ago when I changed. The parts are well-tested: they are a stock 460 Ford distributor, brainbox and coil and literally drop into a 351-C; the gear is also correct but still needs to be double-pinned. One other addition: use a later Ford e-coil rather than a stock can-of-oil coil for more temp stability. A can-coil will overheat from leaving the key ON with the engine OFF for more than 5 minutes; the coil will heat up, boil the oil inside, rupture the case, short and take out the Duraspark brainbox as well as a few wires. E-coils are immune to this problem, saving you $75 extra in repair parts. Sure, the parts are available anywhere but its still 30 minutes and $75 to swap out the burned up stuff. I have actually done all this to our Pantera; its not theoretical and it worked (still is working) for me.

Superwrench. What is an e coil? That's not like what you get from eating bad burgers is it?