351 C Engine rebuild. Not an expert, want some solid advice.

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Don C

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Do you know what camshaft and specs that you are going with? The camshaft, valve train, intake, carburetor, exhaust and gearing all enter into the equation and need to be compatible.

 

kcmash

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1971 Mach 1, Grabber Blue w/Argent stripes. Original 2V 351C Auto, Tilt, rear defog, Black Comfortweave Interior. Under restoration. Original colors, 4V 351C, 4-Speed, Spoilers, Magnums, Ram Air. All Ford parts.
Carb:  Holley 670 Ultra   
CAM: 220/230 @ .050", 112 LSA, 109 ICL, .553"/.588" lift.  Morel Link Bar Lifters-roller

Exhaust:  4v exhaust manifolds, 2.25 dia pipes, h-pipe, dual exhaust.

4 speed close ratio, 3:25 rear posi.  15 inch magnums.

Intake: that is the choice here.

kcmash

 

TommyK

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You could use the stock intake and it will "work" but with those engine specs you would be leaving power on the table except for torque in the very low rpm range. Ask Brent what intake he recommends for your combo. I suspect it will be the Blue Thunder or the Air Gap. If budget limits you to using one of the intakes you already own, use the Eddy IMO.

 
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You could use the stock intake and it will "work" but with those engine specs you would be leaving power on the table except for torque in the very low rpm range. Ask Brent what intake he recommends for your combo. I suspect it will be the Blue Thunder or the Air Gap. If budget limits you to using one of the intakes you already own, use the Eddy IMO.
+1 to this advice. What the Air Gap has going for it is that the BT is hard to find.

 

kcmash

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Yep, budge is going to be a constraint considering the unexpected career change I am facing.  As everyone has noted, the intake is pretty easy to swap in the grand scheme of things.  I have just been confused on the whole setup since this is an area I have never designed in before.  I can’t afford to go trial and error, and there is no data to compare on various intakes.

I thought I understood that the factory cast iron was the same runner and casting profile as the Boss 351 Intake, so my initial thoughts were to stick with what Ford designed, but the community says Clevelands like the dual plane for low end performance which is where this one will be 80% of the time.  Not sure what the difference is between the Air Gap and the 2665.  In the pictures it looks like they milled out some of the dividing wall between the 2 planes.  Of course I am sure there is more to it than that.

Thanks for the opinions and advice.

kcmash

 

c9zx

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Given what you have said about how you use the car, I'd run the Edelbrock intake. Chuck

 

Hemikiller

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Factory iron intakes and their aluminum counterparts are identical except for the material they are cast in, and the carburetor pad machining. The D1ZX-CA B351 intake is used with the 4300D spreadbore, and you'd need to butcher it pretty good to use with a square bore Holley. If you want that Ford part #, get the over the counter D1ZX-DA which will accept up to an 850 Holley. 

Air Gaps are on backorder until who knows when. I've seen dates into early 2022. 

Blue Thunder intakes are available fairly easily, this seller on eBay has them in stock. 

https://www.ebay.com/itm/265362879211?chn=ps&norover=1&mkevt=1&mkrid=711-117182-37290-0&mkcid=2&itemid=265362879211&targetid=1262749491742&device=c&mktype=&googleloc=1014739&poi=&campaignid=14859008593&mkgroupid=130497710760&rlsatarget=pla-1262749491742&abcId=9300678&merchantid=119233579&gclid=Cj0KCQjww4OMBhCUARIsAILndv4P8XBdHTv4UymiOj8lEUWzqlJLYPSVxxnOWlCZ_f0y13WC4Z5R1FEaAkrREALw_wcB

Dan Jones did a compilation of intakes many years ago, I've attached a Word doc with the information, plus another covering the basics of modifications. He also did a bunch of back to back dyno testing with intakes on a fairly mild 351C Pantera engine. I created a graph to show the difference between the stock intake and Air Gap. They did test the Performer IIRC, info in link below. 

https://www.corral.net/threads/budget-351c-rebuild-and-dyno-test.2092114/

351C_STOCK_VS_AIRGAP.JPG

351C_BASICS_DANJONES.docx 351C_INTAKE_DANJONES.docx

 

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kcmash

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Here is the damaged piston #6

20211102_161416.jpg

20211102_161404.jpg

 

kcmash

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Well, I am getting petty perturbed with everything!

Just got word that the camshaft I was expecting any time doesn’t even have a blank assigned.  Nothing against the person or the suggestions from here, but this really has me frustrated.  I was all geared up for the roller cam, had it speced out, ordered the roller lifters, new valves, etc.

Now my engine is on hold, and I have no idea if a cam will ever show up.  I am so sick of hearing there are supply chain issues!

So here is my question.  Should I just go back to my flat tappet M6250-A341 that was in it when I dropped the valve?  The cam looks perfect, and it is broke in.  Brent Lykins said he thinks won’t produce any power, but people on the web seem to speak highly of it.  If I wait for the custom cam I will probably not have a car in 2022 just because of a cam.

No, I don’t want to change cams later.

No, I do not have a bunch of money thanks to Honeywell FM&T F’n me over and putting me on the street on false accusations.

No, I am not building a race car.  Reliability and fun are more important than races.

Any suggestions on CAM shops that can actually deliver a cam soon?

Any thoughts on the A341 cam?

Thanks,

kcmash

 
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That SVO cam is perfect for a mild build 351 C with power brakes, a stock or slight higher stall speed converter, and 3.25/3.00 gears, and a lower compression engine. It will work fine with a higher compression engine, but it will also work with a lower compression engine, which bigger cams usually will not. I see no reason why it will not make any power. It just will not make a ton of power higher up in the RPM range, but it will have good vacuum, good drivability, and good low end torque. Cams are all about compromises. If you want a ton of power, then you get a big cam to be able to make a ton of power at higher RPM, but your drivability suffers, you will not be able to run power brakes, you will need low gears, a big converter, high compression etc... You can probably make another 30-50hp with a cam in the 230-240 duration range at .050, but then you have to deal with all the drawbacks. I will be doing my 351C and I like a Lunati Vodoo roller cam with 219 @.050 duration. I will be running 3.50 gears, 10:1 compression and 3.50 gears. If I went with a bigger cam I will have problems with the power brakes. [email protected] should get me about 15 inches of vacuum which will be enough to run power brakes. If I was not running power brakes with the 4 speed and 3.50 gears I would look at something in the [email protected] with 10:1 compression. If I was doing a 5-6 speed transmission conversion. I would probably go to something in the [email protected] duration range, 10.5:1 compression and 4.10/4.30 gears. A [email protected] cam will make all types of power over 4,500 RPM's but it needs the matching components. 

 
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turtle5353

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Get on Summit racing and find a cam in the grind that matches as close as possible to the specs you want and order it up. You dont need a custom grind for your application. They still have some stuff in stock and can have it in a few days.  See if any of those tickle your fancy.  

https://www.summitracing.com/search/department/engines-components/section/camshafts-valvetrain/part-type/camshafts/make/ford/engine-size/5-8l-351/engine-family/ford-cleveland?N=filter-options%3Ain-stock_vendor-in-stock%2Bcam-style%3Ahydraulic-roller-tappet

 
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Hemikiller

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Welcome to the club. I've been waiting since early September for the replacement cam for my engine from Cam Research, scratch them off your list. I drove my 71 a grand total of five miles this year, so we're in the same boat. I'd be careful about getting frustrated and making a snap decision on a cam. 

Ran that SVO cam on a 70 4V engine and it's an excellent street cam, but it's all done at 5500. When I say all done, I mean as in "shuts off like a switch", so I'd never use it again.  I'd also never reuse a cam that came out of an engine that suffered the damage yours did. 

Right now, you are pretty much limited to what's on the shelf, or in for a long wait. Since you already own the roller lifters, then start looking for a similar spec cam as you had on order. If you post the specs, we can probably find an in stock roller with a little Google work.  

 

kcmash

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Welcome to the club. I've been waiting since early September for the replacement cam for my engine from Cam Research, scratch them off your list. I drove my 71 a grand total of five miles this year, so we're in the same boat. I'd be careful about getting frustrated and making a snap decision on a cam. 

Ran that SVO cam on a 70 4V engine and it's an excellent street cam, but it's all done at 5500. When I say all done, I mean as in "shuts off like a switch", so I'd never use it again.  I'd also never reuse a cam that came out of an engine that suffered the damage yours did. 

Right now, you are pretty much limited to what's on the shelf, or in for a long wait. Since you already own the roller lifters, then start looking for a similar spec cam as you had on order. If you post the specs, we can probably find an in stock roller with a little Google work.  
Thanks for the information and coaching!  Funny thing is I am trying Cam Research as they said they had roller blanks in stock and quoted me 4 weeks to get it done.  Everyone else said they were at the mercy of the supply chain with no forecast available.   Even Brent Lykins, (who I am fully supportive of, no bad press here)  Was supposed to have my roller cam months ago.  He thought they had blanks assigned to my job, then on the due date they said, "no, we will assign a blank when it comes available".  Brent said he had no forecast, my machine shop is waiting on the cam, so wish me luck that Cam Research can meet their forecast.

kcmash

 

Hemikiller

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Thanks for the information and coaching!  Funny thing is I am trying Cam Research as they said they had roller blanks in stock and quoted me 4 weeks to get it done.  Everyone else said they were at the mercy of the supply chain with no forecast available.   Even Brent Lykins, (who I am fully supportive of, no bad press here)  Was supposed to have my roller cam months ago.  He thought they had blanks assigned to my job, then on the due date they said, "no, we will assign a blank when it comes available".  Brent said he had no forecast, my machine shop is waiting on the cam, so wish me luck that Cam Research can meet their forecast.

kcmash


I just talked to Scott at Cam Research on Tues, 12/14 and he told me roller blanks were "fifteen days out", which is what I heard back in late September. At that time, he told me there was a waiting list ahead of me, this time I'm "first in line". My cam is a warranty replacement for the solid flat that failed due to soft lifters he supplied. He did say the roller lifters were in stock though. Right now I'm looking at an alternative that's in stock, as my engine builder won't start putting anything back together until he has a cam. 

Worst case, I have a Lunati solid in the box that I will run, just need to source a set of lifters that won't fail.

 

kcmash

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I just talked to Scott at Cam Research on Tues, 12/14 and he told me roller blanks were "fifteen days out", which is what I heard back in late September. At that time, he told me there was a waiting list ahead of me, this time I'm "first in line". My cam is a warranty replacement for the solid flat that failed due to soft lifters he supplied. He did say the roller lifters were in stock though. Right now I'm looking at an alternative that's in stock, as my engine builder won't start putting anything back together until he has a cam. 

Worst case, I have a Lunati solid in the box that I will run, just need to source a set of lifters that won't fail.
What Lifters gave you problems.  Lykins sold me Morel Link Bar lifters, but I had to return as Cam Research says they will only sell cam and lifters together.  I ordered last week and Scott told me it would be 4 weeks but he would try to better that.  

I don't know the camshaft supply chain process.  Does your grind specification govern what blank you use?  Not sure.  I just hope these guys listened and didn't sell me a cam that will tank my power brakes and driveability.

I'll keep you posted.

kcmash

 

Hemikiller

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Scott supplied the cam and lifter set on my original purchase. It was a solid flat tappet cam with 230°/235° duration. I also paid to have it run in on their "Cam King" machine as an extra precaution. Lifters came numbered by the hole they go in with a map on the box, and I was there when my builder was taking the engine apart. They were in the correct holes for certain. Box had an EPW (Engine Parts Warehouse) label under the Cam Research sticker, so I'm guessing they were just off the shelf stock replacement type lifters. I don't know where EPW gets their lifters, but this batch was definitely bad, since he warrantied the whole deal. I sent everything back to him for hardness testing. 

I'm not well versed in cam manufacturing. From what I've read, you only have a couple companies that supply all of the cores to everyone else. 351C is essentially a "dead" engine, so it gets moved to the back of the line for parts supply. My guess is that the crate motor companies like Blueprint and ATK are eating up much of the available cam production capacity and the smaller players and oddball engines get pushed to the back of the line. No idea what level of completion CR buys their cores at. My WAG would be fully machined except for the lobes. 

 

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if your budget allows buy a good set of brand name heads, afr or edelbrock. Comp cams has a roller conversion kit for Clevelands. pick one of them. i used the one with .566' lift but its been so long...if the box is in the attic ill get the pn for you. I don't like a lopey idle. this ran smoothly and had great vacuum and mad power. BUILD IT YOURSELF and use an in marker to witness mark every bolt and write out a checklist to verify you did everything. sounds goofy but trust me its worth doing. nothing wrong with the heads you have mind you, the others are just better I had the same closed chambered 4 v heads and went aftermarket. The difference is amazing. A 393 would be a blast if you are so inclined and cost wise not far off from what you will pay to install buy and install new pistons , oh yeah have the rotating assembly balanced. 2 things ill never buy again is a carb or a flat tappet cam...just my .02 hope this is helpful
 

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All the parts are finished and I am doing the assembly.

Question of the day. Do I need to prime the hydraulic roller lifters or soak them or anything? I can not find any guidance from Morel, or Cam Research on this subject. These are roller, link bar lifters. I plan to fully prime the engine and set the valve lash per Ford instructions for an adjustable valve train.

Kcmash
 

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I would contact Morel and ask what they think the preload should be. Probably around .030 but I'd still ask them. Assuming a 7/16"x20 TPI stud, 1 full turn is .050. I hope all goes well on the build. Chuck
 
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