Ported Edelbrock versus W2 out of the box !

[PRH]

I’ll agree with some of that, but it seems like the “bulk” of people building these under 575hp SB strokers sure like the idea of being able to do it on pump gas, which is much easier to accomplish when you have good quench........ which is just easier to obtain with off the shelf pistons and closed chamber heads.
One can modify the 60779 RPM head chamber if they want to unshroud the valves a bit, but it would still have a closed chamber that easily facilitates quench.

Yes, you can get there with open chamber heads, like w2’s, but with the added cost of custom pistons.

My point is, it’s just not necessary at that power level.
I’m not advocating for anyone to swap out their w2’s for RPM heads.......but, if you’re starting from scratch, and the target power level is under 575hp...... the RPM’s are a pretty easy path to that result.

This is what I initially was responding to. You listed closed chamber feature as a benefit on the Edelbrock head. And it can be. I am simply saying that the feature is not always a benefit if it is restricting the overall performance of the head.

If the build parameters are based on the desire to make up to about 575hp, IMO the closed chamber is a benefit of using these heads in that application, and still allow for sufficient flow to meet that goal.

 

[PRH]

A similar build to the one I posted the dyno sheet on, built several years earlier...... with a roller cam, more porting, 2.05 valves, and a regular Victor with a 4150/4500 adapter and a 1050 dominator made 589hp.

10.2’s @132 at about 3200lbs.

 

[Duane]

I’ll agree with some of that, but it seems like the “bulk” of people building these under 575hp SB strokers sure like the idea of being able to do it on pump gas, which is much easier to accomplish when you have good quench........ which is just easier to obtain with off the shelf pistons and closed chamber heads.
One can modify the 60779 RPM head chamber if they want to unshroud the valves a bit, but it would still have a closed chamber that easily facilitates quench.

Yes, you can get there with open chamber heads, like w2’s, but with the added cost of custom pistons.

My point is, it’s just not necessary at that power level.
I’m not advocating for anyone to swap out their w2’s for RPM heads.......but, if you’re starting from scratch, and the target power level is under 575hp...... the RPM’s are a pretty easy path to that result.



If the build parameters are based on the desire to make up to about 575hp, IMO the closed chamber is a benefit of using these heads in that application, and still allow for sufficient flow to meet that goal.

Not much I disagree with there.
Couple things though, Ross does make an off the shelf piston for a 4.00 stroke that supposedly will work with any head.
Also I have seen some builders machine the w2 down to the point that it is essentially a closed chamber.
Those type issues come down to personal goals of the build. As I have said earlier, the edelbrock total cost wise is hard to beat.

 

[PRH]

Easy peasy......
SRP 220156, zero deck, ootb 60779, .040 gasket..... 10.3cr...... with good quench.

Roughly +/- one cc for each .10 change in CR.

 

[MOPAROFFICIAL]

That certainly doesn’t seem to be the direction things are going.

If that was really the hot ticket for everything ...... I wonder why they’d start out with chambers as small as:

View attachment 1715269429

Vizard has some interesting results in his SBC porting book relating to this.
Even though the “open” chamber SBC heads(that have the same port configuration) flow more than the equivalent “closed” chamber head, and even after equalizing the chamber volume so the CR remains the same for the test, the closed chamber heads made more power.

Flow more, I said. Wins in the flow race.
Closed and even closed with quench adds to power on top of that.
This is a small mopar forum, so to not debate to infinity and beyond.. that's not the law for every head under the sun...Some flow great with not much or any chamber. Port design and height, and of course... 'overall shape' can be the exception to the rule, but we're just going to talk small block Chrysler for the moment.
I'm not saying open makes more power in every case...I am saying you'll typically see less shrouding and better flow numbers with mopar stuff..and I'll even add that if you pick other parts to do the same job as a closed quench chamber...you'll probably come out on top ...or run the same.

 

[PRH]

I'm not saying open makes more power in every case...I am saying you'll typically see less shrouding and better flow numbers with mopar stuff.....

And yet...... even Ma Mopar decided to abandon the open chamber for all successive W series heads after the W2.

 

[rumblefish360]

You mean like all those 700, 800, 900, 1000hp builds based on the 360-1, W8, W9, Victor heads that are all closed chamber.

I haven't seen a W2 make north of 650 myself. Which IMO, I think is awesome for a head designed and released in the early/mid 70's. A W5 could take you further, if it holds up under porting.

Intake:
Lift———A/B

.100—-70.5/67.5 .........100 ---76.1/57.1
.200—139.1/142.8 .......200 - 124.3/111.0
.300—203.2/207.6 .......300 - 159.3/150.0
.400—237.5/241.2 ........400 - 177.4/167.1
.500—252.8/256.1 .......500 - 179.3/170.8
.600—255.5/260.6 .......600 - 181.4/174.4

My W5 flow differences;

My guy @ on the left w/a 4.03 plate
Porters report on flow 4.125 plate
.........int......exh.........int.........exh

100 - 60.......53........ Not recorded
200 - 115.5 ..100.4.........121...112
300 - 172.5...141.8.........180...252
400 - 230......176.9.........228...284
500 - 275.7...198.1.........278...206
600 - 294......212...........308...218
650-------------------------312
700 - 288.6.....222__________235

A shame they gave up the ghost at this level.

A similar build to the one I posted the dyno sheet on, built several years earlier...... with a roller cam, more porting, 2.05 valves, and a regular Victor with a 4150/4500 adapter and a 1050 dominator made 589hp.

10.2’s @132 at about 3200lbs.

WOO! - HOO! Would you have the head & cam specs on that build?

I have to agree with you. A big inch small block with wel done Edelbrock heads will make some nice power on pump gas which is all the rage and I can't argue ether. It is noise to have that HP and big torque on tight quench pump gas in a small package. In the past, that is how I did my 360's. Zero deck w/Edelbrocks and a .039 head gasket make a nice engine. Simple to build really. Nothing fancy, makes good power.

With a 420+ cube engine on the track, your giving A LOT away to the upper W's. They would be great if they weren't SO cost prohibitive in the past. WAY outta my league. They still are today for the most part.

Buy chance.... would you have any comparisons for the W9 VS Victor head available?
OOTB & ported?

 

[PRH]

I’m not really the small block Mopar authority...... so I rarely see any of the higher end stuff unless it finds itself here for freshening.
Never had any W9’s here(or W7’s, and only one set of W8’s), and the Vics are still pretty new to the market.
I think I’ve only had 2 or 3 sets of W5’s here...... years ago.

On that RPM headed motor...... it wasn’t pump gas. Iirc, about 11.7:1.
Heads flowed 285-ish(I’ve never figured out where the 300+ magic is with those), cam was like 264/268-108, .640-ish, 1.5 rockers.
It was built using an R block though...... 4.100 x 4.00.

Flow numbers between your numbers are pretty close til after .500 on the intake side.

 

[PRH]

More on topic info......

Circa 2008

Ootb new W2 with valve seats recut.
Intake to 2.055, exhaust still at 1.60.
Flowed on 4.00 bore.
Intake valve has back cut.

Lift——-in/ex
.100—-60.4/47.7
.200—118.5/100.3
.300—171.7/129.5
.400—216.9/147.8
.500—252.2/154.9
.600—240.7/154.9
.700—236.9/154.9

Bowl porting and profile the short turns, and basic minor clean up of the rest of the port(castings were pretty rough in the ports).

Lift——-in/ex
.100—-63.0/47.1
.200—131.0/105.4
.300—191.2/152.9
.400—232.3/184.1
.500—268.8/197.3
.600—278.4/204.9
.700—279.5/208.7

 

[rumblefish360]

I’m not really the small block Mopar authority...... unless it finds itself here for freshening.

On that RPM headed motor...... it wasn’t pump gas. Iirc, about 11.7:1.
Heads flowed 285-ish(I’ve never figured out where the 300+ magic is with those), cam was like 264/268-108, .640-ish, 1.5 rockers.
It was built using an R block though...... 4.100 x 4.00.

Flow numbers between your numbers are pretty close til after .500 on the intake side.

S/B heads.... I do know you get it though. I can see that! lol
Stout cam & comp. ratio for sure. Not exactly what I'd call a street cam...
4.100 X 4.0 is big. Love a big bore when available.

I think the spread had more to do with the bore size testing the head. There is a big difference between the .03 and the .125. Ether way, it should stillmake for a good head. I think plenty of power is available through them. Biggest key is a light weight car. Mighty and major head flow is a plus but not the end all by far.

Thanks

 

[PRH]

There is a big difference between the .03 and the .125.

I prefer to think of it this way........ there can be a noticable difference in flow when using different sized bore adapters.
But, I’ve tested numerous heads on different bore sizes where it either did nothing, or hardly anything.
It’s not an “automatic” gain in flow on the bigger bore.

I had some fairly well ported T/A heads here that flowed quite a bit less on my bench than the place that ported them was getting.
I thought maybe they had been flowed on a big bore, and I was using 4.00, so I tried them on a 4.25. Basically no difference.
That wasn’t why the numbers were different.

4.100 X 4.0 is big

I just did the math...... it’s a 422.
This build was quite a while ago, and I seem to recall it was a “419”(4.080 x 4.00).......but I also seem to recall it was 4.100 bore.
It’s one or the other....... can’t remember for sure which.

Stout cam & comp. ratio for sure. Not exactly what I'd call a street cam

Yeh...... if I were building something more street and user friendly, I’d probably be targeting 550hp or so.

I’m not sure what I’d use for a build where the goal was another 100hp above that.
Probably some 360-1’s.
—————————————
Here’s a home ported W2 that was sent to me to test.
2.08/1.60 valves....... the whole port has had work done to it, along with some finishing with sandpaper rolls.
The intake short turn needs some attention, and the proportions of the bowl are a bit off, which is at least part of the soft low/mid-lift flow.
4.00” bore.

Lift——-in/ex
.100—-61.5/52.0
.200—116.2/111.7
.300—168.7/152.5
.400—213.1/187.9
.500—252.2/206.2
.600—272.6/208.7
.700—257.0/210.8

 

[pittsburghracer]

S/B heads.... I do know you get it though. I can see that! lol
Stout cam & comp. ratio for sure. Not exactly what I'd call a street cam...
4.100 X 4.0 is big. Love a big bore when available.

I think the spread had more to do with the bore size testing the head. There is a big difference between the .03 and the .125. Ether way, it should stillmake for a good head. I think plenty of power is available through them. Biggest key is a light weight car. Mighty and major head flow is a plus but not the end all by far.

Thanks

Not sure why someone would want to check small block Mopar heads on a 4.125 fixture but it should produce some good numbers. My fixture is 4.010 in size.

 

[Duane]

And yet...... even Ma Mopar decided to abandon the open chamber for all successive W series heads after the W2.

I am not a cylinder head authority either, but correct me if I am wrong.
Aside from Chamber shape, head flow, quench etc, is not part of the reason for the trend towards closed chamber also because it allows for a lighter weight rod and piston assembly and a flat top piston which also helps the flame front
As I started to build my first 4.0 stroker I started to realize that everything about the overall engine is better.
Because of the longer stroke and increased swept volume, it was easier to get a high compression ratio, even with an open chamber, and without a dome on the piston.
Again because of the longer stroke, the wrist pin sits higher up in the piston, allowing for a shorter overall length piston, again making the weight of the piston much lighter.
Because of the flat or dished piston top, and a closed chamber head
You get a better overall burn rate.
My old stock stroke 340 piston Were really heavy with a huge dome
that struggled to get 10.9:1 compression after the valve reliefs were cut to clear a .585 lift cam.
My new stroker with the same heads has a measly .100 flat dome,
Weigh at least 200 grams lighter, clear a .700 lift cam easily at 12.7:1 compression.
These stroker motors, even with a modest performance head, seems to me cannot lose.

 

[B3422w5]

To anybody posting on this thread, and others...... the guy posting as PRH on here is one of the sharpest Mopar head guys in the country. Believe me
I hope nobody runs him off this board. His info is spot on and very helpful. Glad you showed up here Dwayne.

Carry on..... lol

 

[fishmens67]

To anybody posting on this thread, and others...... the guy posting as PRH on here is one of the sharpest Mopar head guys in the country. Believe me
I hope nobody runs him off this board. His info is spot on and very helpful. Glad you showed up here Dwayne.

Carry on..... lol

If you're are into performance, you know who Dwayne is. I am glad he joined this board.
now, I won't have to go to Moparts for his knowledge.

 

[PRH]

Duane, just to reiterate...... in the Mopar world...... the difference between what’s considered an “open” or “closed” chamber head is only the portion of the chamber that’s opposite the spark plug.
The quench/squish area of the chamber.
If this is even with the deck of the head, it’s a closed chamber.
If there is an area there that’s pulled up off the deck surface, it’s an open chamber head.

On a SB head, this area would only be a couple of cc’s worth of volume, so it has little impact on the CR, and in itself has virtually no impact on flow.

What it does impact though, is how easily one can build a motor that has effective quench.

Open:

Closed:

 

[Duane]

Duane, just to reiterate...... in the Mopar world...... the difference between what’s considered an “open” or “closed” chamber head is only the portion of the chamber that’s opposite the spark plug.
The quench/squish area of the chamber.
If this is even with the deck of the head, it’s a closed chamber.
If there is an area there that’s pulled up off the deck surface, it’s an open chamber head.

On a SB head, this area would only be a couple of cc’s worth of volume, so it has little impact on the CR, and in itself has virtually no impact on flow.

What it does impact though, is how easily one can build a motor that has effective quench.

Yes thanks for that clarification, but I was not confused on that.
What you can educate me on is this quench itself and its effects.
As I stated earlier I have seen that small raised area milled away by some builders.
Welcome to the forum by the way.

 

[rumblefish360]

I prefer to think of it this way........ there can be a noticable difference in flow when using different sized bore adapters.
But, I’ve tested numerous heads on different bore sizes where it either did nothing, or hardly anything.
It’s not an “automatic” gain in flow on the bigger bore.

I had some fairly well ported T/A heads here that flowed quite a bit less on my bench than the place that ported them was getting.
I thought maybe they had been flowed on a big bore, and I was using 4.00, so I tried them on a 4.25. Basically no difference.
That wasn’t why the numbers were different.

I just did the math...... it’s a 422.

I’m not sure what I’d use for a build where the goal was another 100hp above that.
Probably some 360-1’s.

Thanks for the input and thoughts. Perhaps the head chambers played a roll in flow? The T/A heads mentioned, were they factory T/A heads or Indy heads?
On the 360 Indy heads, looking at Shadydell speed shops site as a ref point, the oval head looks a equal or a possible shade better than the iron W2 and the rectangle Indy looks about the same to the W5. Big flow numbers for ether head. Thats just Ryans findings on each head. Flow numbers aside, he is getting about the same head to head. I'm not pointing fingers or saying anything, just stating what Ryan found. I don't want to poke a bear on porting.

Not sure why someone would want to check small block Mopar heads on a 4.125 fixture but it should produce some good numbers. My fixture is 4.010 in size.

Some guys have gone with a big bore small block. MoPar used to sell such big bore blocks and engines. No more, danm shame! Ritter is it. IDK what he actuallty gets for a block and what needs to be done in extra cost. Hughesengines lists on there site for plus $3700 and states it still needs work. It is a little rich for my blood currently. Maybe after a lotto victory!?!?!?

I am not a cylinder head authority either, but correct me if I am wrong.
Aside from Chamber shape, head flow, quench etc, is not part of the reason for the trend towards closed chamber also because it allows for a lighter weight rod and piston assembly and a flat top piston which also helps the flame front
As I started to build my first 4.0 stroker I started to realize that everything about the overall engine is better.
Because of the longer stroke and increased swept volume, it was easier to get a high compression ratio, even with an open chamber, and without a dome on the piston.
Again because of the longer stroke, the wrist pin sits higher up in the piston, allowing for a shorter overall length piston, again making the weight of the piston much lighter.
Because of the flat or dished piston top, and a closed chamber head
You get a better overall burn rate.
My old stock stroke 340 piston Were really heavy with a huge dome
that struggled to get 10.9:1 compression after the valve reliefs were cut to clear a .585 lift cam.
My new stroker with the same heads has a measly .100 flat dome,
Weigh at least 200 grams lighter, clear a .700 lift cam easily at 12.7:1 compression.
These stroker motors, even with a modest performance head, seems to me cannot lose.

IDK the finer details of cylinder head tech and what goes on inside the chamber. Having built modest small blocks with both closed aluminum and open iron, I like the closed aluminum. The only thing I look at on the aluminum head is for clearance of the valcves to the chamber wall and open theming them up is OK. Vizard has some thoughts on that. I have read over at speed talk and other places where head porters gather and read up on stuff. (A little bit.)

Betweenthe 2 heads, I'd rather not use a dome (Unless serious racing is the goal) and just get the valves unshrouded for easy entrance and exit of the cylinder & heads. Effiecnt breathing no matter what. Which chamber provides the best? Beats me! But ether head shows a mighty abilty in power production!

As I said earlier, I like the flat top slug and a closed chamberd head (AKA Edelbrocks) which worked very well at zero deck. A sizeable cam and 93 octane was just fine here.
I do like the idea of a light weight slug in a stroker application. A lot depends on how short the slug gets. I don't know much about longevity and the slugs rocking around. I'd like to build a big incher and have it last a long time. I don't think I'll see a 100,000 miles out of it but.... LOL!

 

[PRH]

Rather than typing out a loooong response.......

What Is The Ideal Quench Height? - Hot Rod Magazine

Quench vs Squish:

Quench

The short version:

Proper quench creates turbulence in the combustion chamber, theoretically pushing the mixture toward the spark plug and reducing the possibility of unburned gases at the completion of the combustion cycle, which can play a significant role in reducing detonation and even exhaust emissions.

As I mentioned earlier, it can be done with open chamber heads, I’ve done it myself several times.
It’s just easier ....... and generally less expensive to achieve ..... with closed chamber heads.

 

[PRH]

The T/A heads mentioned, were they factory T/A heads or Indy heads?

Factory T/A heads, used on a FAST build.

Interestingly, those heads were being used with effective quench.
The quench pads in the heads had been equalized and custom quench dome pistons were used.

 

[Duane]

Rather than typing out a loooong response.......

What Is The Ideal Quench Height? - Hot Rod Magazine

The short version:



As I mentioned earlier, it can be done with open chamber heads, I’ve done it myself several times.
It’s just easier to get....... and generally less expensive..... with closed chamber heads.

Thanks for the link. I always called that piston to head clearance,
But only ever checked it for mechanical interference.
Never checked it to optimize for quench.

 

[PRH]

It is the piston to head clearance....... and if you keep that distance within the preferred range...... there are benefits to be had.

My old 448 with open chambers ran pretty decent for what it was.......10.70’s @3670lbs.
9.7cr, 155psi cranking compression, quench distance of nearly .150..... which means no effective quench....... spark knocked like crazy on pump super(94 at time).
Built with the same CR, cam, etc...... but with a quench distance of .040-.045, I have no doubt it would have been just fine on pump premium.

Subsequent builds I have done that utilized quench dome pistons and a proper quench distance, some with even higher(than 155psi) cranking pressures, have all run just fine on pump premium...... which is only 91 in some of the locations those engines live.

 

[Duane]

p slug and a closed chamberd head (AKA Edelbrocks) which worked very well at zero deck. A sizeable cam and 93 octane was just fine here.
I do like the idea of a light weight slug in a stroker application. A lot depends on how short the slug gets. I don't know much about longevity and the slugs rocking around. I'd like to build a big incher and have it last a long time. I don't think I'll see a 100,000 miles out of it but.... LOL!

My Ross Pistons were much shorter than stock but they also recommend a piston to wall clearance of only .004.
I thought that was pretty tight for a forged piston, but I have to trust the piston engineers on that. Just like the current theories on big ring gaps on the 2nd ring nowadays.

 

[Duane]

It is the piston to head clearance....... and if you keep that distance within the preferred range...... there are benefits to be had.

My old 448 with open chambers ran pretty decent for what it was.......10.70’s @3670lbs.
9.7cr, 155psi cranking compression, quench distance of nearly .150..... which means no effective quench....... spark knocked like crazy on pump super(94 at time).
Built with the same CR, cam, etc...... but with a quench distance of .040-.045, I have no doubt it would have been just fine on pump premium.

Subsequent builds I have done that utilized quench dome pistons and a proper quench distance, some with even higher(than 155psi) cranking pressures, have all run just fine on pump premium...... which is only 91 in some of the locations those engines live.

This would explain the trend then towards closed chambers with flat top Pistons. I never really paid attention to octane requirements because my build was planned for strip only with high octane fuel in mind.
Where does the trend towards aluminum fit in with the quench issue.

 

[PRH]

Quench dome piston for use with open chamber style heads:
The little dome fits into the open quench pad area of the heads.

So, there needs to be some planning involved so you end up with the little dome being within .040-.045 from the quench area of the head at tdc when assembled.
Getting the quench area of the heads equalized, and the correct depth, with the chambers at the correct finished volume for the desired final CR is usually the biggest challenge when going about it this way.

Much simpler with flat tops or inverted domes and closed chamber heads.