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When I go to the machine shop what all do I want them to do to my heads if I go this route instead of running aluminum's?  List please. :D

 

What porting should I do before taking the heads to the machine shop?  gasket match intake and exhaust ports?  Smooth out exhaust ports?  Any polishing for the intake ports?

Thanks!

Wade

1972 Mach 1 351 cj 4speed

"We confide in our strength, without boasting of it; we respect that of others, without fearing it."--Thomas Jefferson

 

 

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Thanks! I am still trying to decide if I want to go aluminum or keep the iron heads. Im guessing it will be about a $500 difference if I go edelbrocks or stick with machining the iron heads. Any thoughts, advice??

Thanks!

Wade

1972 Mach 1 351 cj 4speed

"We confide in our strength, without boasting of it; we respect that of others, without fearing it."--Thomas Jefferson

 

 

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Minor port cleanup, do not polish the intake ports, 3-angle valve seats. Minor roughness creates turbulence which helps to mix, and keep mixed, the fuel and air particles.

 

Have the heads machined for adjustable rocker arms, have the valve guides checked for wear and proper clearances and replaced if needed. Knurling the guides is OK for minor wear. Have the valve guides machined for positive valve seals.

 

 

“If you can't explain it simply, you don't understand it well enough.”

--Albert Einstein

 

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I would say if you want to modify the performance, go with the Aluminum heads. 

 

 I really agree with the posted article above, in spite of claims of professionalism, the 4V head is kinda misunderstood.  Look at it this way, the Boss 351 engine is known for being a high performance Cleveland engine.  I don't believe there is any difference in the ports on the quench chamber 4V vs the Boss Heads.  The performance comes from the camshaft, the carb, the pistons, and the rear gear ratio.   So why go custom on such a well engineered head?  I have actually heard that the obvious"hump" on the exhaust side that all hot rodders want to grind away is actually a benefit to exhaust gas flow by creating a converging-diverging nozzle effect.

 

kcmash

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Thanks!  I am still trying to decide if I want to go aluminum or keep the iron heads.  Im guessing it will be about a $500 difference if I go edelbrocks or stick with machining the iron heads.  Any thoughts, advice??

 

Exactly what is your goal?

 

Do you want more bottom end?

 

Do you want less bottom end but more rpm on top?

 

 

I wouldn't touch the ports unless you are an experienced head porter.

 

You will get the most overall power from chi heads. If you want big time power, you should buy chi heads.

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I went through this dilemma with my CC 4Vs. After reading and researching a lot i decided to keep the casting stock except for the valve angle job and machined for rocker screw in studs. I also cleaned and smoothed the chambers a little.

 

Sent from my SAMSUNG-SM-G930A using Tapatalk

20160929_171923_edit2_small.jpg

 

1971 M-Code Mach 1 w/Ram Air, 408 stroker, 285/291 0.558" roller cam, Blue Thunder intake, TKO600, Hooker headers with electric cut-offs, FiTech EFI w/ RobBMC PowerSurge pump

Strange center section with Truetrac, 3.5 gear and 31 spline axles, 4-wheel disc brakes

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If you want to make the low end a bit better, go for some Aussi 2V CC heads.  They have the best of both US 2V and 4V heads.

The only real difference between the 2v heads you have and the Aussie heads is the combustion chamber. To take advantage of the Aussie closed chamber you will need pistons that create a quench area, doing this and keeping the same compression you currently have may allow you to decrease your octane requirements. A good quench area has the ability to make the motor more resistant to knock.

 

 

Then theres also these.... if you really want something killer.....

 

http://www.chiheads.com.au/product-category/heads/ford-cylinder-heads/3v/

"I drank what?" - Socrates

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I am running AFD SP4V Heads and they are very comparable to the CHI 3v heads. I love them and they make monster power.

 

https://www.afdheads.com/collections/cleveland-heads/products/afd-sp4v-3v-bare-alloy-cleveland-cylinder-heads?variant=34022411022

Kevin
1971 Mach 1

408C Stroker - C4 w/3,000 stall - 8.8" Rear w/3.73's - Disc brakes all way around.

 

044.jpg

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Thanks!  I am still trying to decide if I want to go aluminum or keep the iron heads.  Im guessing it will be about a $500 difference if I go edelbrocks or stick with machining the iron heads.  Any thoughts, advice??

 

Exactly what is your goal?

 

Do you want more bottom end?

 

Do you want less bottom end but more rpm on top?

 

 

I wouldn't touch the ports unless you are an experienced head porter.

 

You will get the most overall power from chi heads. If you want big time power, you should buy chi heads.

It will be a cruiser, occasional trip down the strip.  I want low end power

 

 

 

+1 on chi's they're what I'm running, although mine are 2v. If you wanna see them you're close enough that it wouldn't be a big deal.

WOW!  You are close.  I work in uptown Charlotte.

 

 

I am running AFD SP4V Heads and they are very comparable to the CHI 3v heads.  I love them and they make monster power.  

 

https://www.afdheads.com/collections/cleveland-heads/products/afd-sp4v-3v-bare-alloy-cleveland-cylinder-heads?variant=34022411022

 

Looks like these are almost $1700 per head.

Thanks!

Wade

1972 Mach 1 351 cj 4speed

"We confide in our strength, without boasting of it; we respect that of others, without fearing it."--Thomas Jefferson

 

 

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Thanks!  I am still trying to decide if I want to go aluminum or keep the iron heads.  Im guessing it will be about a $500 difference if I go edelbrocks or stick with machining the iron heads.  Any thoughts, advice??

 

Exactly what is your goal?

 

Do you want more bottom end?

 

Do you want less bottom end but more rpm on top?

 

 

I wouldn't touch the ports unless you are an experienced head porter.

 

You will get the most overall power from chi heads. If you want big time power, you should buy chi heads.

It will be a cruiser, occasional trip down the strip.  I want low end power

 

With this info, I'm going to say you should skip the aftermarket heads, have yours machined as recommended, and get a custom ground cam that matches George Pence's recommendations on the links I provided to the Pantera board. He has guys getting up to 450hp out of a relatively stock 351C-4V with a custom cam and excellent low end power. The 4V head has unique cam requirements because of the huge valve size, what works on an 351W or a 429 does not work on a 351C. While the Pantera can have a better exhaust layout, even 350-400hp is very respectable on the street. Rule of thumb with cams, when in doubt, go with the smaller grind.

 

 

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Thanks!  I am still trying to decide if I want to go aluminum or keep the iron heads.  Im guessing it will be about a $500 difference if I go edelbrocks or stick with machining the iron heads.  Any thoughts, advice??

 

Exactly what is your goal?

 

Do you want more bottom end?

 

Do you want less bottom end but more rpm on top?

 

 

I wouldn't touch the ports unless you are an experienced head porter.

 

You will get the most overall power from chi heads. If you want big time power, you should buy chi heads.

It will be a cruiser, occasional trip down the strip.  I want low end power

 

 

 

+1 on chi's they're what I'm running, although mine are 2v. If you wanna see them you're close enough that it wouldn't be a big deal.

WOW!  You are close.  I work in uptown Charlotte.

 

 

I am running AFD SP4V Heads and they are very comparable to the CHI 3v heads.  I love them and they make monster power.  

 

https://www.afdheads.com/collections/cleveland-heads/products/afd-sp4v-3v-bare-alloy-cleveland-cylinder-heads?variant=34022411022

 

Looks like these are almost $1700 per head.

 

No that's a set of 2.

Kevin
1971 Mach 1

408C Stroker - C4 w/3,000 stall - 8.8" Rear w/3.73's - Disc brakes all way around.

 

044.jpg

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Do everything that Hemikiller said and get a good intake like a Blue Thunder or an AirGap along with a good carb and some 3.50 - 3.70 gears. You’ll have a blast on the street and be respectable at the strip without breaking the bank. You can always add more later. Plus if you go with much more hp then you will need to start beefing up the rest of the car to handle it.

Good luck with whatever you decide to do  :)

John - 72 Q Code

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as long as you don't f-up a set of 4vCC heads by porting them, they will always be worth $500-700 bucks down the road-more is possible.

http://www.7173mustangs.com/gallery/1_01_07_15_8_53_18.png

 

"I love my Hookers!" and "Get some Strange" probably have a different connotation to non automotive enthusiasts!

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yes, gearing will increase the acceleration rate. i mentioned this on somebody's thread a few days ago.

 

if you want faster acceleration, the most effective things to do are either install a numerically higher gear ratio or increase the engine displacement.

 

in general, the bigger the cam, the numerically higher the gear ratio must be for a street car to compensate for the loss of low end power (not a land speed record attempt car).

 

if you change the ratio by 2 steps, it will be very noticeable but not a huge day and night difference. if you change it by 3 steps it will be a day and night difference, however, of course the engine will rev more per each mph you drive so without an overdrive trans. 3:50 gears are typically the numerically highest ratio one should go and 3.40 is a good ratio for a performance car that sees a fair bit of freeway driving.

 

What are your rear gears?

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Thanks!  I am still trying to decide if I want to go aluminum or keep the iron heads.  Im guessing it will be about a $500 difference if I go edelbrocks or stick with machining the iron heads.  Any thoughts, advice??

 

Exactly what is your goal?

 

Do you want more bottom end?

 

Do you want less bottom end but more rpm on top?

 

 

I wouldn't touch the ports unless you are an experienced head porter.

 

You will get the most overall power from chi heads. If you want big time power, you should buy chi heads.

 

:huh: :huh:

 

What are your rear gears?

 

I'm guessing the stock gear 3:23???

Thanks!

Wade

1972 Mach 1 351 cj 4speed

"We confide in our strength, without boasting of it; we respect that of others, without fearing it."--Thomas Jefferson

 

 

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Here he covers the entire engine.

 

https://pantera.infopop.cc/topic/sticky-3-351c-basics-and-performance-tuning

 

351CJ specific

 

https://pantera.infopop.cc/topic/cobra-jet-unleashing-the-performance-capabilities-of-351-cleveland-engines-with-open-chamber-4v-heads-q-code

 

Post with cam specs etc

 

https://pantera.infopop.cc/topic/questions-regarding-george-s-275-285-custom-street-cam-profile

 

 

Might be worth a shot to join the forum and ask George for a specific recommendation for the Mach 1, considering the intake and exhaust differences over a Pantera.

 

 

-

 

 

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What are your rear gears?

 

I'm guessing the stock gear 3:23???

 

ok, then if you want faster acceleration and don't drive long distances at 70 mph, i would install numerically higher gears in your specific case. the best ratio for you just needs to be determined. then of course a different cam etc, but again, just a cam alone won't change much. if you install a smaller cam, it will have more low end power and less rpm but it won't make it accelerate much faster.

 

here is an rpm vs mph gear ratio calculator you can play with.

 

 

http://www.wallaceracing.com/gear-speed.php

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something overlooked if these are open chamber V4 heads throw them in the garbage and get closed chamber heads.

 

If this is your point of view, can I at least ask that you throw them in MY garbage?  OC heads get a bad rep, but with pop ups, they work great and there is less intake valve shrouding-just because you don't like them is no reason to think they are garbage.

http://www.7173mustangs.com/gallery/1_01_07_15_8_53_18.png

 

"I love my Hookers!" and "Get some Strange" probably have a different connotation to non automotive enthusiasts!

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something overlooked if these are open chamber V4 heads throw them in the garbage and get closed chamber heads.

 

If this is your point of view, can I at least ask that you throw them in MY garbage?  OC heads get a bad rep, but with pop ups, they work great and there is less intake valve shrouding-just because you don't like them is no reason to think they are garbage.

 

Agreed, nothing wrong with them, just require the correct pistons.

 

 

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Is there a way to tell which heads I have with the engine in the car??  As long as the numbers match like the PO said then it should be a 72 351cj.

 

Also, Did the heads not have the correct pistons stock???

Thanks!

Wade

1972 Mach 1 351 cj 4speed

"We confide in our strength, without boasting of it; we respect that of others, without fearing it."--Thomas Jefferson

 

 

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The purpose of the open chambers was to reduce compression in an effort to meet the new emissions requirements. For '72 the pistons were still flat top.

 

'72 4V heads had the large ports and valves with an open chamber. The chamber size is approximately 75.4 cc, compared to approximately 62.8 cc for closed chamber heads.

 

Thinking about stroking your engine? CJ (Q code) heads with flat top pistons should give suitable static and dynamic (with proper camshaft) compression ratios for pump gas.

 

 

“If you can't explain it simply, you don't understand it well enough.”

--Albert Einstein

 

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