Dished Pistons for 4v Quench Heads?

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Yes - Flat top pistons and quench heads will ping on anything less than 93 octane.

No - Dished pistons and quench heads will not ping even on 87 octane.

Having the block zero decked will raise the compression and get you closer to pinging and will cost $ that you do not need to spend to reach your stated goal.

I did some simple math and came up with 8.3 compression on quench heads and 1973 dished pistons. You will be building a 140hp M code 4V Cleveland and I wholeheartedly approve! You might even crack 20mpg with a well tuned carb and distributor.

Your 140hp 20mpg M code 4V Cleveland will run great and pull your Grande down the road just peachy.

If you want it to sound tough then run dual glass packs and it will sound like a NASCAR plus you will pick up another 1/2 mpg or so - FUN!

There is a term for this - it is call ecomodding. Some ecomoders have built "drivable" cars that get 90 plus mpg and they are every bit of a motor head as I am - all be it quite a bit more strange.

Build it! You can do it! Come on build it!

- Paul
I think I can hear some snickering going on out there in the forum...

You really think only 140hp? The large 4v ports might be a hindrance to low rpm power, but that is what got me thinking about the Aussie/Trick Flow type heads with smaller ports and a quench chamber, the trade off being cash outlay for new, non-original heads and getting more port velocity in exchange (plus 'exotic' imported or aluminum heads to get back the 'wow' factor). Might bring the hp back up and get a better torque curve. The Aussie heads are about 60cc as I recall.

I've been following some of the 'hypermiling' work people are doing. It's amazing how effective combining lots of little improvements in efficiency can add up.

Not a Grande, though, it's that 71 M code sportsroof with the full vinyl top you posted about last winter/spring.

The cheerleading helps, keep it up. How do you look with 'pom-poms'?



I have flat tops and quench heads (see sig for details). Pings on 91 octane which is the highest commonly available here. Currently I have it mixed to just over 93 octane and it pings just a little. Next tank I am going to bump it up to 94.

I don't drive the car much so I don't mind fussing with the gas. I don't get good gas mileage either, 9 or 10 mpg tops. Except for the pinging it is streetable, idles well but that's because of the Rhodes lifters and they do make a lot of noise.

I am just providing this as reference. I can see that your goal is to avoid some of this (mixing gas, pinging, etc) so it's a good example of what you do not want to do.
More info that helps. Think your cam has anything to do with the mpg? I see you've got 3.50 gears and an overdrive, I'd expect more than 9-10, but how much city/highway?


RottenRalph:

I'm looking at a 5 speed with overdrive, so the 3.0:1 in it now might be as low as I would want to go. I have an idea for an Explorer 8.8 and those are typically 3.55 or 3.73. The 3.55 is usually not a lsd, so if I have to install a lsd/locker, then I could swap to 3.23 also.

What kind of mpg do you get and what kind of driving mix (city/highway)?


Chuck-

I've looked at the S1159 with a supposed CR of 7.9. I've also read that Ford rated the CR higher than it was, so how do the aftermarket/replacement CR specs compare? More questions....
Most show a Compression Height/Distance of 1.660-1.662 which is about .013-.015 higher than stock. I believe that is because they know that Ford built the engines with the piston down the bore .015 or more. They want to have the piston at or near the top of the bore (close to zero deck). If you have the heads off you can use a dial indicator to determine how far down the bore your piston are. Zero deck is desirable to minimize the quench distance (see previous post). With that information you can do the math to determine what the best piston match is. Plan on having the block decked to get at or near zero deck. Which machine shop you use is absolutely CRITICAL. Find one that has experience building Clevelands, with good outcomes, if possible. Seemingly small things like how deep the front cam bearing is set matter. Nothing about engine building is as simple as some might believe. Do all the math yourself. Verify everything is compatible before you buy parts and measure the parts before they are used. Verify everything as the engine is being assembled. Trust but verify.

As far as detonation goes shoot for a dynamic compression ratio of about 7.75-8.1. Dynamic compression ratio is not the "end all" of predicting resistance to detonation but, it is a good indicator.

Use a cruising speed vs. rpm calculator to figure out cruising RPM and use that as one consideration when choosing a cam. Chuck
It's never as easy as anyone thinks it is...can't buy pistons til I figure out the heads and can't get heads til I figure out the pistons and can't decide on a cam til I know gears which I can't decide on til I know tire diameter. Rinse and repeat. Change one thing and every thing else changes, or maybe not.
Can't afford to place an order with an engine builder, so I have to figure it all out, but I'm early on the learning curve with the Cleveland. Just researching will occupy my winter.



These are the factory '73/74 pistons:

IMG_0299_zpsdb0d6782.jpg
Thank you for the pic, that helps, too.
 
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check out Coast High Performance ...they make a rotating assembly for 351C which ends up being a 357 at 9.5-10.2 CR with small chamber heads and dished pistons.

 
I'll have a look, thanks!

 
I look stunning in my cheer leading outfit!

8.3 is what you will see with the overlap in the economy cam and low pin location on the dished pistons. Get a thick head gasket and an even more conservative cam and you can drop it even lower.

With a zero decked block and a normal street/strip cam and it would be just over 9.5:1 and might ping on 87.

You are doing what everyone does including me - start out just wanting to build a simple engine to drive the car and then add heads, and then need a bigger cam, and then put on headers, and then upgrade the carb, and then this and then that and then when all is said and done you have a 300hp engine just like everyone else but now you have a car that is not all that fun to drive normally and is certainly no fun to feed.

It would be fun and different to ecomod a M code and keep it looking like a M code.

One of the coolest cars I have seen this year was a 71 Sports Roof 6 cyl 3 speed manual. It is a high quality build and is done up like a Mach inside and out. When the hood gets opened everyone goes "wait - what"

I basically described how many people have goofed up when building a Cleveland and then wondered where all their HP went.

Want to maintain acceptable HP an up the MPG?:

Take a set of 2V heads and intake - epoxy up the runners to increase velocity.

Destroked crank to get the swept volume down to around 330 cubic inches

Find or have a custom cam ground to maximize MPG - low lift, lots of overlap.

Use a new carb like EFI system such as Atomic and tune it for 350 to 400cfm

Put in a AOD or 5 speed along with a 2.75 rear end gear.

End up with around 175hp at the rear wheels. Plenty of HP to drive the car and even brake torque the rear wheels if you needed to.

Mileage? Maybe as much as 30mpg on the highway and low 20's around town.

Keep the M code look - grind off the 2's and use epoxy to build up some little 4's (and don't forget the dot). Hide everything under the Ram Air system.

Dual exhaust with Flowmasters or Borlas and it will sound right.

Not the cheapest build - probably will have 5K in the whole drive train.

Use what you save in fuel cost to fund all the other things that an old car continuously needs.

- Paul

 
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I look stunning in my cheer leading outfit!

8.3 is what you will see with the overlap in the economy cam and low pin location on the dished pistons. Get a thick head gasket and an even more conservative cam and you can drop it even lower.

With a zero decked block and a normal street/strip cam and it would be just over 9.5:1 and might ping on 87.

You are doing what everyone does including me - start out just wanting to build a simple engine to drive the car and then add heads, and then need a bigger cam, and then put on headers, and then upgrade the carb, and then this and then that and then when all is said and done you have a 300hp engine just like everyone else but now you have a car that is not all that fun to drive normally and is certainly no fun to feed.

It would be fun and different to ecomod a M code and keep it looking like a M code.

One of the coolest cars I have seen this year was a 71 Sports Roof 6 cyl 3 speed manual. It is a high quality build and is done up like a Mach inside and out. When the hood gets opened everyone goes "wait - what"

I basically described how many people have goofed up when building a Cleveland and then wondered where all their HP went.

Want to maintain acceptable HP an up the MPG?:

Take a set of 2V heads and intake - epoxy up the runners to increase velocity.

Destroked crank to get the swept volume down to around 330 cubic inches

Find or have a custom cam ground to maximize MPG - low lift, lots of overlap.

Use a new carb like EFI system such as Atomic and tune it for 350 to 400cfm

Put in a AOD or 5 speed along with a 2.75 rear end gear.

End up with around 175hp at the rear wheels. Plenty of HP to drive the car and even brake torque the rear wheels if you needed to.

Mileage? Maybe as much as 30mpg on the highway and low 20's around town.

Keep the M code look - grind off the 2's and use epoxy to build up some little 4's (and don't forget the dot). Hide everything under the Ram Air system.

Dual exhaust with Flowmasters or Borlas and it will sound right.

Not the cheapest build - probably will have 5K in the whole drive train.

Use what you save in fuel cost to fund all the other things that an old car continuously needs.

- Paul
Still trying to get the cheerleader image out of my head....need the space for important thinking!

8.3 or 175hp at the wheels sounds lower than the effort would be worth. At that point a well tuned 302 would make better sense, especially with FI, for the mpg and drivability goals, but not for the stock M-code look. But as you point out "scope creep".

So if I creep, what is your opinion of the Trick Flow 190 head with the 72 cc chambers? Dished or flattop? Aluminum and quench to fight pinging etc., but a little more compression and 2v ports to keep air velocity up. I'm thinking torque over hp and no more than 3.23 gears with an overdrive. I'll be at least a grand into decent iron heads, so the cost difference isn't that bad.

I did happen to pickup a set of 73 dished pistons/rods (out of a low mileage Italian exotic...with CJ type oil pan). Getting the crank and might get the heads. Not sure if the heads will be used for anything, just a decent price figure it out later kind of deal.

The 330 Ecode sounds interesting, but it would need someone far more knowledgeable and experienced than I to make sure it is planned and executed to achieve the goals.

Any recommendations on an engine builder/machine shop in the area? I don't need the most expensive, just trustworthy and that knows a bit about the Cleveland.

 
"8.3 or 175hp at the wheels sounds lower than the effort would be worth. At that point a well tuned 302 would make better sense, especially with FI, for the mpg and drivability goals, but not for the stock M-code look."

175 at the rear wheels is over 200 at the flywheel. Not too shabby.

For what you want I would just rebuild the M code engine/4V heads with the H code pistons and a very mild of the shelf cam. It will run on cheap gas and will be very well mannered.

If you want to have fun then get an Atomic EFI or something like it and it should run even better.

You could also just go 30 overbore with flat top pistons like everyone does but keep the timing backed off so it does not ping. That along with an "economy cam" and a small CFM carb will get you exactly what you want without over thinking it.

It is the cam profile and carb specs that will effect what you are doing most.

The destroked cranks was just for maxing out the eco mod project and would not be cheap.

The mileage difference between a built 302 and this "detuned" 351C would not be all that much.

302's are like armpits - everyone has 2. 351C are much cooler!

- Paul

 
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I think I prefer cool armpits...

Looks like I'm getting the 73 OC 4v heads. So the question is, 71 flattops and 73 OC 4v heads, or 73 dished 4v pistons and CC or OC 4v heads?

 
I think I prefer cool armpits...

Looks like I'm getting the 73 OC 4v heads. So the question is, 71 flattops and 73 OC 4v heads, or 73 dished 4v pistons and CC or OC 4v heads?

HEADS AND PISTONS

imo, you would better off running 2v closed chamber heads at 64 cc’s with a .005” piston to deck height and 13cc dished [pistons like the ones below . . this way you still have some quench area and compression.

I would then do a mild pocket port and valve guide blend and and back cut the intake valves. install slightly larger valves if you want. either way you still have decent velocity and decent flow for 350 hp easy.

heres the pistons, and they are decent but inexpensive and have gas accumulators

http://www.summitracing.com/parts/uem-kb148-030/overview/make/ford

CAMS

get a custom cam or look at comp xe262h or xe268h which is the biggest you would want to go . . bullet cams, cam research, straub technologies . . do not use comp cam lifters.

GEARS

you need to calculate your final drive ratio . . you would want to be around 1700 rpm for max mileage with the 262 and maybe 1900 rpm with the 268 . . if you are below the power range your mileage will decrease. i would look at 3.23 - 3.50 gears depending on your tire size and fiunal drive . . the 3.5 would be my choice for the 282 cam for your app but i would run 3.73 with them . . the 3.40 might be good with the 262 cam if you want some pep off the line . . the stock 8 inch can easily take 400 hp with decent parts. i wouldn't spend my money on an explorer rear for your app . . i would use a std type 3 finger 1700 lb pressure plate from mcleod.

rpm vs mph calc

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

CARB

An annular venturi type will give you the most mileage and power for your app . . i would look at 650 cfm carb.

.

 
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I think I prefer cool armpits...

Looks like I'm getting the 73 OC 4v heads. So the question is, 71 flattops and 73 OC 4v heads, or 73 dished 4v pistons and CC or OC 4v heads?
Wear cotton t-shirts...

If you are getting some OC heads then use them. Bore the block 30 over and get some flatops. This will save you some money and will be fine on mid grade or higher fuel.

New ARP rod bolts and fresh bearings and life will be good.

Clevelands never need to be ported of polished or have bigger valves installed for street use. We regularly epoxied up the runners to make them smaller.

Hardened seats and fresh guides are all that the OC heads will need.

You may choose to replace the ford valves with one piece units but I honestly have never had one fail on a street motor. You can over rev and float a valve and have the keepers come off (bad) and then drop a valve into the engine (really loud and bad) but I have never had the valve itself come apart.

You are building a 250hp street Cleveland just like everyone else does. That is cool.

Keep the cam mild and target the 1500 to 4000 rpm range and don't go nuts with the carb. 600 to 700 cfm vac 2nd's will be plenty.

You will get 15ish miles per gallon and it will be ok but not totally hassle free to drive just like everyone else's. Nothing wrong with that.

Take pictures and keep us posted.

I personally still think you should eco mod an M code but it is easy for me to spend your money for you - LOL.

One thing I have not measured is the valve relief on the stock 73 dished pistons.

You need to make certain that the great big 4V valves are not going to hit the stock 73 piston at TDC. Flatops have and those "inexpensive" Summit aftermarket 4V dished pistons have a valve relief cut into them.

I forget that not everyone has the fly cutting jigs needed to add a valve relief to a piston so I did not think of it as a possible show stopper for your project - sorry about that.

Find someone who has built your typical performance street Cleveland and go for a ride. See if you like it and ask lots of questions. Find several someone's

Beware of creep!

- Paul

 
Thanks for the input Paul. I did pickup the heads tonight. Since I haven't spent any real money yet, all options are open. With the parts I have I could build a fake 71 Cobra Jet ( a Cobble Jet?). I need to check the flattop pistons in my block to see if they are 2v or 71 4v. The pistons I picked up should be good with the OC heads as they came out of the same 73 4v motor, supposedly all original Ford. If the heads turn out to have issues like cracks, then maybe I save my pennies and look at the Trick Flows. I'd just hate to spend $4-500 on a set of used heads and then more to have them magged only to find out they are junk. I could easily spend more than half of what a new set of aluminum heads would and still be no closer to the original goal.

I had similar thoughts on the cam, something around a 260.

One advantage of the using all the 73 parts is the motor should be around 300lbs/ft, this would keep it within the range of the Ford 5 speeds, 2.9something 1st and .82 or .64 overdrive.

One of my considerations if I go the eco route, how long to recoup the costs in fuel savings. Not sure that will balance out. If I save $2k on the build, that covers a lot of premium price difference.

What to do, what to do...

Still, I'd rather be a scope creep than a boost retard...

 
For the best mileage a used offy dual port intake is one good option along with the annular booster carb i mentioned especially with those huge ports in those heads . . I would also run a 192 thermostat because you can run leaner jetting with a warmer engine and therefore get better mileage . the engine will also last longer due to reduced wear . . If you want your power in the lower rpm range then yes a smaller cam than the 268 would be better . . The 256 would be the smallest I would go and will probably give better mileage than the 262 but the 262 would be a better match for those heads due to their huge ports imo . . FYI . . If I remember right the 73 4v heads have 2v valves .

 
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Remember, the 351M/400's turned into pinging monsters on low octane due to excessive deck clearance - in no small part thanks to those dished pistons.

You've got a good idea to use closed chamber heads though; the quench helps fight pinging issues.

Just don't duplicate the engineering issues of the 351M/400, or you'll wind up running 93 just to combat the pinging. Funny thing: My stock 400 is so prone to pinging (with or without EGR, with or without timing recurve, etc.) and has such a low compression ratio that I've come to believe that sticking a turbocharger on it may be the second-easiest solution (!). First solution would be to get rid of it.

-Kurt

 
Build what you want. But if you run CC heads with dished pistons, you are really wasting money. Increased compression results in increased efficiency.

Quench height is the free space between the piston at the top of its stroke and the head and has to be held to a fairly tight range to allow a quench head to . . . well quench!

So here is a different formula-build a 302 Cleveland

You can use quench 2V (Aussie) heads and a small 600 CFM Vacuum Secondary Carb on an appropriate dual plane intake. (If you run 4V heads, you'll probably want to try out some port fillers to improve low speed airflow) Run it in a car with a 3.25 or 3.00 rear end and you'll be able to milk decent mileage out of it and get some fairly impressive performance. A custom Cam builder can help you acheive your goals. I would not be afraid of 10:1 compression ratio-I get by regularly with 93 octane in a 11.5-1 393 Cleveland and while it requires a good tuning, it isn't rocket science.

Better mileage will never come from reduced compression ratios. A smaller displacement engine can be more efficient however.

Personally for your goals, a 5.0 EFI transplant from a late fox body would probably work and be much cheaper.

 
For the best mileage a used offy dual port intake is one good option along with the annular booster carb i mentioned especially with those huge ports in those heads . . I would also run a 192 thermostat because you can run leaner jetting with a warmer engine and therefore get better mileage . the engine will also last longer due to reduced wear . . If you want your power in the lower rpm range then yes a smaller cam than the 268 would be better . . The 256 would be the smallest I would go and will probably give better mileage than the 262 but the 262 would be a better match for those heads due to their huge ports imo . . FYI . . If I remember right the 73 4v heads have 2v valves .
The intake is one of the things to figure out...once I've got the piston/head combination figured out. I've wondered about the dual port Offenhauser and if it lives up to it's claims.
I've heard different things about the 73 4v valve sizes. Including some reports that they've never found the small valve 4v heads in a Mustang or that it was a late year thing. I'm wondering if that might have something to do with the two different hp ratings, 248 and 266 for the 73 4v. I'll measure the valves this week, but since the heads didn't come from a Mustang, not sure how much that will me. The date code on both heads I think is 2H8.



Remember, the 351M/400's turned into pinging monsters on low octane due to excessive deck clearance - in no small part thanks to those dished pistons.

You've got a good idea to use closed chamber heads though; the quench helps fight pinging issues.

Just don't duplicate the engineering issues of the 351M/400, or you'll wind up running 93 just to combat the pinging. Funny thing: My stock 400 is so prone to pinging (with or without EGR, with or without timing recurve, etc.) and has such a low compression ratio that I've come to believe that sticking a turbocharger on it may be the second-easiest solution (!). First solution would be to get rid of it.

-Kurt
The books say 78 cc for the 351m/400 and 75.4 for the 73 4v/CJ. That is one of the questions that prompted this thread, is the pinging issue more related to the open chamber or the dished pistons or just combustion chamber volume regardless of head/piston. Since the complaints are typically with stock type OC heads, then I was wondering if switching to the Trick Flow 72cc head with dished pistons (factory or aftermarket) to bring compression back down would counter the pinging. The heads being aluminum would also help reduce heat and therefore pinging.


Build what you want. But if you run CC heads with dished pistons, you are really wasting money. Increased compression results in increased efficiency.

Quench height is the free space between the piston at the top of its stroke and the head and has to be held to a fairly tight range to allow a quench head to . . . well quench!

So here is a different formula-build a 302 Cleveland

You can use quench 2V (Aussie) heads and a small 600 CFM Vacuum Secondary Carb on an appropriate dual plane intake. (If you run 4V heads, you'll probably want to try out some port fillers to improve low speed airflow) Run it in a car with a 3.25 or 3.00 rear end and you'll be able to milk decent mileage out of it and get some fairly impressive performance. A custom Cam builder can help you acheive your goals. I would not be afraid of 10:1 compression ratio-I get by regularly with 93 octane in a 11.5-1 393 Cleveland and while it requires a good tuning, it isn't rocket science.

Better mileage will never come from reduced compression ratios. A smaller displacement engine can be more efficient however.

Personally for your goals, a 5.0 EFI transplant from a late fox body would probably work and be much cheaper.
Which leads to Jeff's post about the Aussie heads. The Trick Flow heads have the 2v ports like the Aussie heads (and raised ports at that) to keep up the intake velocity. Since the Trick Flow heads are offered with 62 and 72 cc options, I went looking for pics of the 72 cc head to see exactly what the combustion chambers look like, but have only found various pics that appear to be the same type head with no clear indication of which one it is (although I suspect all the pics I see show the 62cc head for promotional materials). I still do not know how different the 62 and 72 cc chambers look on the TF heads. It all might be a pointless mental exercise.
I'm assuming you mean the actual 302 heads with the 59cc chamber. I contemplated the 302 crank and pistons/rods for a destroked motor (similar to Paul's 330 suggestion). Not sure what the compression ratio is on that motor.

I was hoping for MPG thru conservative tuning (small carb/cam overdrive and the right final drive) without high compression and fussy fuel considerations. That's why all the postulating on head/piston combinations. One of the key ingredients is the small intake runner/port velocity. My desire to figure out a way to run OEM 4v heads without falling flat was my own monkey wrench. The TF heads looked like a way around that, not OEM, but a certain amount of cool factor with advantages of their own.

The 5.0 EFI (Ford not aftermarket) was an option I'd considered originally for a 65-66 coupe idea I had with the same high MPG freeway commuter concept. MUCH lighter car so it would have been even more effective. I think that car could have hit 25-28mpg on the highway at 60mph-ish with 205 tires. Not much less than my Protégé gets now.

I think my plan is changing slightly. Since I am diving into a new learning curve with the Cleveland and I've acquired the 4v heads for too good a price, I am seriously considering building the components I have into a more or less stock OC 4v motor with either dished or flattop pistons. This gets my feet wet building a motor myself with some idea of what it should be and as I learn what I'm doing I can plan for the other motor. This will keep costs down for now and get a livable motor in the car sooner. Trying to hotrod while learning is usually a good way to burn money and be wrong, so I will spend a bunch less and learn more for now.

 
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.

.

The intake is one of the things to figure out...once I've got the piston/head combination figured out.
Hello Detritusmaximus;

It seems to me that the only thing you need to figure out are your exact, realistic, performance goals . . high hp = bad mileage . . low hp = better mileage . . If you want 400 hp and killer power from 0 to 6000 rpm and 54 mpg I would buy a Chevy LS-1 car . . Unfortunately, you just can’t get big hp and big mileage at the same time in a carbureted, non computer controlled engine.

There looks to me to be a wealth of knowledge and firsthand experience on these engines from others that have posted here so I don’t see a reason for you to go thru the trial and error process of “figuring” anything out by yourself . . I would simply take the general consensus of others here and maybe do a bit more research online on aussie 2v closed chamber heads and you will come to the same conclusion that about 10 million zillion others have, which is that those heads are the ONLY way to go in mild to moderate Cleveland builds. Every single thing about them is superior to ANY stock 4v Cleveland head for this type of app.

I have been building engines a repairing and restoring cars for a living for around 40 years . . I have done a lot of Cleveland stuff as others here have and i guarantee you from 40 years of on hands experience that what some others here have told you about open vs closed chamber heads etc s true . . As I mentioned earlier, even if your heads have the 2v valves, they still have 4v ports, therefore, the flow velocity is too low for you . . Also, again, the closed chamber heads with a small od, shallow dish in a piston will have far less detonation potential than open chamber with flat tops, it's a simple fact.

bare aussie heads

http://www.ausfordparts.com/ausheads.html

rebuilt aussie heads and ported aussie heads and porting services

http://www.powerheads.com

there is currently a set of used eddy heads on ebay for around $900.00

heres others

Aussie aluminum heads

http://www.ebay.com/itm/DIY-Ford-302-351C-Cleveland-235cc-78cc-CNC-Hydr-R-Complete-Alloy-Cylinder-Heads-/171429026633#ht_11067wt_1230

decent Chinese heads auction ends tomorrow. Should bring 1,000.00 but 150.00 shipping

http://www.ebay.com/itm/PAIR-FORD-PRO-COMP-351-CLEVELAND-ALUMINUM-PERFORMANCE-CYLINDER-HEADS-/261647527754#ht_938wt_1167

As far as pistons go, the one I listed has a flat outer edge on top like stock which will provide some quench on closed chamber heads only, plus the dish is extremely shallow so you will get more quench from those than a deep dish Ford piston will on any head . . As I mentioned, imo, you positively need 71 thru 73 big valve valve closed chamber 2v heads for the best match for your app . . The aluminum heads are great and need flat top pistons . . All these options need the pistons no more than .005 below the deck.

The Offy dual port works just like it was intended to. I've had them and one of the "authorities" on Clevelands has had some and says the same thing . . The people that say they don't work were expecting the wrong thing from them

There is no such thing as too good of a price on parts that are not only not even remotely best for an app but really are pretty useless.

 
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The Trick Flow heads have the 2v ports like the Aussie heads (and raised ports at that) to keep up the intake velocity.
no, they have exhaust ports that are raised on the top and bottom just like 99.999% of all super high perf aftermarket heads in the world do . . this increases ex flow because it creates a smoother transition from the ex valve to the exit . . this smoother transition reduces turbulence that is created on the floor of the stock heads . . there are aftermarket gimmicks called port stuffers for the 4v cleveland heads that are designed to raise the ex floor which reduces volume a bit but increases velocity/flow per se due to less turbulence . . it's complicated.
 
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Beware, Ford moved piston compression distance around to lower CR. You don't want the piston down the hole. No matter what piston you use have the block zero decked for that piston. Use gasket compressed thickness to set the quench distance (.035-.040).

From Beck Racing (not an endorsement, just info.): Excessive cylinder pressure will encourage engine-destroying detonation and no piston is immune to its' effects. An important first step is to set the assembled quench (a.k.a. "squish") distance to .040". The quench distance is the compressed thickness of the head gasket plus the deck clearance (the distance your piston is down in the bore). If your piston height (not dome height) is above the block deck, subtract the overage from the gasket thickness to get a true assembled quench distance. The quench area is the flat part of the piston that would contact a similar flat area on the cylinder head if you had .000" assembled quench height. In a running engine, the .040" quench decreases to a close collision between the piston and cylinder head. The shock wave from the close collision drives air at high velocity through the combustion chamber. This movement tends to cool hot spots, averages the chamber temperature, reduces detonation and increases power. Take note, on the exhaust cycle, some cooling of the piston occurs due to the closeness of the water- cooled head. Chuck

 
BOOGERS! Great greasy green boogers!

The 4v heads are in great shape, but.....small valve.

More soul searching....

 
BOOGERS! Great greasy green boogers!

The 4v heads are in great shape, but.....small valve.

More soul searching....
well you want/need small valve for your app but you really need the smaller 2v runners too.

aussie heads

 

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