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Joined
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Williamsburg Virginia area
My Car
1972 H code convert., 351C 2V, FMX, 9in., Ram air, Pwr Steering, Pwr Disc brakes, air-conditioning, 15" sport wheels, Ivy Glo w/white deluxe interior.
With a stock 351C ram-air in the car, I thought about making it a 4v. Found a stock spread bore intake and a set of early production closed chamber 4v heads (late'69) from what the numbers state so, the question is, keep the 2v setup or invest the money to rebuild and install the set-up?

A life-long friend who is a co-owner at D.S.S. posed the question of, do we really need a 4v Cleveland at our age? Being half serious, I'm still stuck on the need v want of the situation, but he has a point. Plus, I'm tracking at 8 maybe 10mpg driving it like it's a 51 year old car with 82,000 miles. Add in that it's $4.89gal for 93 nonethanol, it's a $95 to fill'er up. Another concern, there is a slight knock and we're only advanced around 6-7 deg on the distributor. That's a Pertronix stock profile because of the ram-air cleaner housing. It's a really nice kick at that advance so I hate to back it down so the greater concern is, what's it gonna be like when we go to a 58cc chamber?cleveland 4v heads.jpg cleveland 4v heads1.jpg
cleveland 4v heads2.jpg
 
Joined
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Location
Erie, Pennsylvania
My Car
1972 Grabber Blue Mach One 351 Q code orig 4 speed. Now: 427C Titus, TKO 600, 4 wheel discs
Yes, you do want it, therefore, according to the official "Car Guy Instruction Manual" you do  need it! The closed chamber 4v heads with their excellent quench are surprisingly good at avoiding ping. You mentioned you're currently getting some ping at only 6 degrees. Check your total advance. Not knowing your particular setup a very general range is between about 32 to 38 total but lots of variables. Just my thoughts....
 

rio1856

Drive it like you stole it!!!
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Immokalee Fl.
My Car
1972 Mach 1 Q code 351CJ 4Spd Toploader 9" rear end
Cleveland Crush mentioned the manual. I will quote what I just read in the official "Car Guy Instruction Manual". "When dealing with a vintage muscle car. As the vintage vehicle operator gets behind the wheel, please note that the muscle car's throttle position Only has two settings. It will either be off or all the way on. The more power, the better driving experience. So any positive changes to achieve that goal to the muscle car is highly encouraged." Unquote. So dude have at it your sled needs it and you definitely need it! 😁
 

351c1971

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1971 Mach1
Check that your stock distributor is setup with the 13 degree limit (see pix.). The total advance will then be 2 x13 dist. + 10 crank = 36 degrees. also consider an adjustable vacuum advance (Rock Auto).

I have the stock distributor with the Pertronix 1, 2v heads and I run regular with this setup.
 

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Joined
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Location
Erie, Pennsylvania
My Car
1972 Grabber Blue Mach One 351 Q code orig 4 speed. Now: 427C Titus, TKO 600, 4 wheel discs
Cleveland Crush mentioned the manual. I will quote what I just read in the official "Car Guy Instruction Manual". "When dealing with a vintage muscle car. As the vintage vehicle operator gets behind the wheel, please note that the muscle car's throttle position Only has two settings. It will either be off or all the way on. The more power, the better driving experience. So any positive changes to achieve that goal to the muscle car is highly encouraged." Unquote. So dude have at it your sled needs it and you definitely need it! 😁
Affirmative on you quote rio1856. And for those who doubt rio; Please read "The Manual" page 47, paragraph 6, section 2, it's all right there!
 
Joined
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SW Ontario
My Car
1971 Mustang Mach 1, M code, 4 speed.
This is what I found I needed to do to get the best I could get out of my 71 with GA heads which are similar.
The stock set up on the M code motor was a 15L limit slot (30 deg crank) with an initial of 6 deg. = 36 total mechanical. With 11:1 pistons, this rattled like a marble in a tin can. After researching as well as talking to a race car engine builder I knew, I slowly figured out what was needed. After many trials, my engine and cam ran best with a 10L limit slot with 14 deg. initial with about 4-6 deg. vacuum on top. Weight spring choice and tension are also critical to achieving a good smooth curve. With the springs seen in my pic, it's all in at around 3K rpm. I also dropped the compression to 10:1 during a second engine rebuild. This set-up pulls like a train, zero rattle (got rid of the marbles) and give me pretty good milage with a Holley 670 carb, around 14-15 mpg/ US gal. as long as I keep my foot out of it. Hit the loud pedal and watch the gauge drop.
To get the 10L slot, I had to weld up and recut the slot plate. The width dimension is .410". A quick fix is to use a piece of 1/8th NYLON tube over the post. This will cut the travel down to around the equivelent of a 10L. (This can be found on Ford distributors)
 

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Joined
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Mustang, OK.
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1972 Mach 1 Q code
2007 GT
1969 Cougar Eliminator B302
CSX 7000 Shelby Cobra FIA
2020 Edge ST
2002 F250 V10
Just say no to the factory spread bore intake. The 4300D carb that goes with it is nightmare for 99% of the people that try to make it work properly. If you change the heads you will need 4V exhaust manifolds or 4V headers. The 2V stock cam will not be able to support the 4V heads properly. As others have said, if it is pinging now, it is likely that something is wrong with the rate of advance or total timing. The re-man distributors are notorious for have too much vacuum advance. Chuck
 

351c1971

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1971 Mach1
My 600 cfm Holley on the Edelbrock Performer 2v manifold worked fine out of the box. The Holley quick change kit made it easy to fine tune the vacuum secondary springs.
 

351c1971

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1971 Mach1
Rock Auto STANDARD MOTOR PRODUCTS VC31 comes with calibration instructions and fits the stock single point distributor. It adjusts with an Allen wrench in the vacuum port.
Well worth the $26.00.
 

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Joined
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Williamsburg Virginia area
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1972 H code convert., 351C 2V, FMX, 9in., Ram air, Pwr Steering, Pwr Disc brakes, air-conditioning, 15" sport wheels, Ivy Glo w/white deluxe interior.
Thank you all for the words of wisdom and advice. More is always invited.

The distributor was actually a pertronix model that was made to be the stock height. The car, being a '72 California car, had the dual vacuum diaphragm installed on the disty but only the main advance is hooked to vacuum. The car has that vacuum solenoid mounted on the drives side, top valve cover bolt/stud combo. It's been damaged and I just kinda "MM'ed" it with a couple vacuum connectors and a thread/tap. (you know, Walt D. School of Auto Engineering, which actually doesn't elicit the same meaning it did 50 years ago) Plastic was still solid enough I could tap it and screw in the threaded connectors. The hoses are connected but eaaled off on the one end so it doesn't effct the retard side of the dual vacuum disty.


Had the car out today to pick up final parts for the Pwr Steering rebuild. The Lares Pump and steering knuckle, head, gearbox, whatever, just arrived. Because of the Fusion mess, just updated that it WILL BE Nov-2023 or Jan. 2024 before the PCM arrives so, I can't take the car down the way it was planned. Heads will have to sit for a bit but you've all talked me into it. It is an H code motor so pistons are not the HiPo CR ones however, we figured the CR will boost to around 11.3:1(+-). Not too shappy. My '66 notchback, I believe I explained this somewhere else here, had a 351w from a '69 Mach 1 Shoehorned into the engine bay. The "frienemy" I boght it from wouldn't sell the heads so one wnet the '66 289 2v heads. Anyhow, those had 56cc chamber heads and I will tell you with the pistons from that 351w, the CR was around 13.5:1, give or take. The car was a screamer for sure. Think I ate up 3 sets of Goodyear Eagles that summer. Alas, that was now 43 years ago so......the new steering will be a good fit for the heads when all is said and done.

Current pic of engine so you can see what I was talking about above.

351 cleveland.jpg

I'm starting another thread about the steering replacement so if there is some words of advice for that, I haven't performed that miracle swap since 1979! I have been reading up on things but.....wasn't wanting to be there now. By the way, there is an air conditioning compressor missing from this picture so why there's some funny looking spaces and the foil like material. It's aluminum duct tape holding two washers together for correct spacing.
 
Joined
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1971 Mustang Mach 1, M code, 4 speed.
When you get to the steering box job, there's tons of thread/post on the subject here. But sometimes it's just easier to ask again.
Bentworker and (dare I say it) myself, have considerable insight from working on and or rebuilding PS boxes. Many others have great knowledge too, so don't be afraid to ask.

If you new motor top end build is going to be anywhere near 11:1, you might have some spark knock issues unless you can get fuel that will support it.
In my above post, I mentioned I dropped the comp ratio back to 10:1. I played around with just about everything I could think of to get the motor to run with 11:1 comp, but eventually, the engine had to be rebuilt again due to an incorrect oil pump (hv) the builder chose to put in. At that point, I had 13cc dish top piston put in. Even then, it took quite a while to find the sweet spot. Don't forget, everything must work together, timing, carb setup, spark plug choice, spark plug leads, engine vacuum and of course cam choice. If any of those are off, good luck getting a good result. That's just one person's opinion, mine.
EDIT: In my case, the best nonethanol gas I can get in my area is 91 octane.
 
Joined
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Williamsburg Virginia area
My Car
1972 H code convert., 351C 2V, FMX, 9in., Ram air, Pwr Steering, Pwr Disc brakes, air-conditioning, 15" sport wheels, Ivy Glo w/white deluxe interior.
In my case, the best nonethanol gas I can get in my area is 91 octane.
Stanglover,

We have an energy company, Phillips Energy (not 66) in town. They sell Sunoco93 nonethanol fuel. The best part is their tanks are above ground! Every other station we have purchased nonethanol from has buried tanks and we've suffered from water every time. Granted it's only a couple cans of Heat but why bother when the Sunoco 93 is a really good fuel. Today, 8.5 gallons, $40 so that's $4.69gal. I'm not even gonna go there, you know, complain and reminisce. That's just the "cost of doing business" if we want to drive these cars.
In an emergency, I have a bottle of gas conditioner in the trunk but it might as well just get tossed out. 90 Super from places like Exxon, BP, Sheetz, the ethanol added fuels are horrible. The car responds horribly with them. It is not just th ethanol at fault, it's the amount of water they blend now. The car is a dog and I refuse to use that fuel any longer.

By the way, someone mentioned about the cam and sizing so it can "keep up" with the 4v heads, right now the carb is the issue with the Ram air. It can't supply enough fuel for the setup and the engine just flattens out before the torque curve is reached.
 
Joined
Aug 27, 2021
Messages
41
Reaction score
8
Location
Williamsburg Virginia area
My Car
1972 H code convert., 351C 2V, FMX, 9in., Ram air, Pwr Steering, Pwr Disc brakes, air-conditioning, 15" sport wheels, Ivy Glo w/white deluxe interior.
Rock Auto STANDARD MOTOR PRODUCTS VC31 comes with calibration instructions and fits the stock single point distributor. It adjusts with an Allen wrench in the vacuum port.
Well worth the $26.00.
I'm looking into this. Missed the mention of the ability to calibrate. That's actually ingenious.
 
Joined
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SW Ontario
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1971 Mustang Mach 1, M code, 4 speed.
Stanglover,

We have an energy company, Phillips Energy (not 66) in town. They sell Sunoco93 nonethanol fuel. The best part is their tanks are above ground! Every other station we have purchased nonethanol from has buried tanks and we've suffered from water every time. Granted it's only a couple cans of Heat but why bother when the Sunoco 93 is a really good fuel. Today, 8.5 gallons, $40 so that's $4.69gal. I'm not even gonna go there, you know, complain and reminisce. That's just the "cost of doing business" if we want to drive these cars.
In an emergency, I have a bottle of gas conditioner in the trunk but it might as well just get tossed out. 90 Super from places like Exxon, BP, Sheetz, the ethanol added fuels are horrible. The car responds horribly with them. It is not just th ethanol at fault, it's the amount of water they blend now. The car is a dog and I refuse to use that fuel any longer.

By the way, someone mentioned about the cam and sizing so it can "keep up" with the 4v heads, right now the carb is the issue with the Ram air. It can't supply enough fuel for the setup and the engine just flattens out before the torque curve is reached.
I hear you. We used to get Sunoco 94 octane with no ethanol, until Petro-Canada took it over and promptly dumped 10% ethanol crap into it. I won't buy it even though I know the car is set up for 15% (if I have to). The only gas I can get at the moment is Shell or one of its sub suppliers like Canadian Tire.
The way things are going here in Canada, we'll be lucky if we can buy ANY gas if the dumb ass Trudeau get his way. He wants 100% electric cars (vehicles) by 2035!! By then I'll be 88, so I may not care anyway.
 
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