[zonker]

I ran across this and it compares all the different 2.3 heads out there.

2.3OHC, your comments please...

[free2.3]

who makes a .700" lift cam!!!!! i want it haha

[zonker]

my boys at web cam can if the you really want... but what in the hell would u use for springs??

as for the flow lists above, it looks like a late dual plug head (95-01?) would be a great starting point for porting since it doesn't need as much compared to a stock d port or early 8 plug (91-94?).

[free2.3]

i dunno id figure it out though. hmm i wonder what base idle would be 11-1200 rpm haha. that would sound fucking awesome i dont think the motor would run well below 4k though.

[zonker]

...it sure would sound great at the stoplight.

[OHC230]

Bo dumped those figures out on the turbo ford forums quite a few years ago. Try not to draw too many conclusions from the statistics, other than the stock heads are very weak in terms of flow volume. What you can’t see from these test results is port velocity or gas momentum, which is extremely important to head performance.


One disparity I saw in this test, was the SVO Esslinger aluminum head, which Bo tested. His results were far below any of my test examples. Now I know Bo to be an honest guy and I don’t believe he fudged any figures here, maybe the head casting he had wasn’t the same as mine, or maybe there were some anomalies in the data, but I saw figures which were about 20% higher when we tested my heads, so I was dissatisfied with the notion that the O.E. ported iron head, was somehow better than the “purpose built Essligner aluminum heads and I have not seen that to be the case, especially when you compare the port velocities of each. I have seen a handful of Mini stock engines on the dyno with both highly ported iron and Essy heads on them. The Essy heads always make more power. That doesn’t mean that Bo doesn’t do fantastic work, it’s just that there are limitations working within the stock port walls and I’ve stated this before, there are areas in the port walls that are less than .300” in thickness, do you think if we cut .250” away and leave just .050 remaining, we might not encounter some issues?? I could delve into this further but we’d get into boring discussions about data collection and I am pressed for time. Don't know if this was what you were looking for??

[zonker]

i'm sure the essy figures are suspect, either due to unfair testing or marketing hype for his own product (even honest people do that).

but the late dual plug oem head... it stands to reason it will need less material removal to obtain good numbers because the flow is already pretty good...

or for the truly incapable, just milling and doing a 95-01 head swap on a 91-93 mustang looks like it will yield promising results.

[OHC230]

Who makes a .700" lift cam!!!!! i want it haha

That's a cam for a 3.0L engine, ARCA head, with a very narrow application range.

[free2.3]

ministocks, theres no way id drive a cam like that on the street.

[OHC230]

Here is the info from BoPorts website regarding this.--------------------------------------------------------------------------

All heads were bone stock other than cleaning carbon off the ports. Factory valve job, same valve used for all tests. This is an intake flow comparison tested at 28" water on my bench. 1/2" clay radius on port entrance. 3.810" test bore on iron heads and 3.92" for esslinger heads. Cylinder number 3 port was used on all tests but the ranger round port, in which cylinder #4 was used. Back to back, same day.


-Lift"---N/A D--Turbo D--OvalD7--Round--LateDual--EarlyDual--EssyD--BoEssyD--BoIronD---ARCA---Volvo16v
.050"---27.55---27.8-----28.6----31.0----30.0------27.3------28.1-----29.6-----31.1------33.7----42.3
.100"---48.9----54.5-----55.9----59.0----58.0------54.9------51.4-----61.3-----61.1------61.3----85.1
.150"---61.8----75.4-----78.9----77.7----86.7------78.3------76.7-----94.5-----94.5------91.6----123.9
.200"---75.2----100.6---100.3---101.6---110.7-----96.1------105.5----123.6----123.0-----122.0---164.1
.250"---88.0----120.7---122.3---122.0---130.3-----109.4-----132.3----147.2----148.5-----149.8---198.5
.300"---101.6---132.3---136.8---135.5---143.3-----120.4-----156.3----169.9----173.2-----175.8---219.2
.350"---116.5---140.1---146.6---142.7---153.1-----128.4-----177.7----189.4----193.9-----198.5---226.4
.400"---131.0---144.0---150.5---145.3---158.9-----132.3-----190.7----207.6----212.7-----218.6---229.6
.450"---144.0---149.2---153.1---145.9---164.1-----134.9-----199.8----220.5----223.1-----236.1---231.6
.500"---151.8---154.4---156.9---149.2---166.8-----136.8-----205.6----231.6----225.7-----252.3---234.1
.550"---158.2---159.5---156.3---150.5---168.8-----138.8-----210.1----236.1--------------265.9---235.4
.600"---163.4---160.8---156.3---151.8---170.2-----140.1-----214.7----237.4--------------275.0---235.4
.650"---------------------------------------------------------206.9-----------------------283.1---------
.700"---------------------------------------------------------207.6-----------------------290.2---------


"N/A D" refers to a naturally aspirated D port head with closed combustion chamber.

"Turbo D" Refers to a open chamber D port used on the turbo EFI engines as well as early carbureted applications.

As you can see, the closed chamber head in stock form flows significantly less than it's open chamber variant due to excessive valve shrouding in the chamber. After proper chamber re-shaping however, the closed chamber head can be made to flow equally well as the open chamber head.

The "BoEssyD" and "BoIronD" are both standard level stage 3 ported heads.

[free2.3]

volvo head.... id expect higher flow for a 16v. id hope my ported head runs almost as much as that if its up on par with bo's

also why deos the stock essy drop off flow so much after 600 lift?

can i run the arca head on my 2.9 project or would it be better running my ported head or buy an essy?

also any one have any info on the racerwalsh power heads?

[OHC230]

Volvo head.... id expect higher flow for a 16v. Id hope my ported head runs almost as much as that if it’s up on par with Bo’s
Having more valves doesn’t always guarantee more flow, since flow is highly dependant on volume. Doubling the diameter of a circle increases its area 4 times, multiply that by the length of the ports and you get quite a lot of volume area. Is volume really the only thing that will give your engine more power?


Why does the stock Essy drop off flow so much after .600” lift?
First of all, some background regarding valve lifts. The following are known principals of valve lifts and gas flow.
Valve lifts in most heads, which are equal to ¼ of the valve seat diameter, will typically result in flows which are 60-65% of the total flow capacity of the port. So if you had a 1” wide valve seat and lifted the valve .250” you would see 60-65% of the max potential port flow. Valve lifts equal to half of the valve seat diameter typically result in 85-90% of the total capacity of the port. For a stock 2300 that would mean that if we measured our valve seat at 1.5” we would be at .75” of lift. So why not put a .75” lift cam in your stock engine? Wouldn’t it make 600 HP?

Not without velocity.

The missing parts of this equation are both momentum and velocity. So, we know that if you increase valve lift, you will continue to gain volume, but what if we just keep extending that valve away from the seat to 1”, 2”,3”, 25 feet: are we going to keep increasing the flow through the port when the valve is one mile away from the valve seat? Would you agree that at some point, that moving the valve further away from the seat, would have no effect? Yes, no, maybe?? Could I make more power with less lift?

One of the ways in which we make more power from an engine, is by increasing the charge density. Now here’s another dense analogy to describe this: If I place a candle 2 feet away from you and I give you a toilet paper tube and a soda straw to blow the candle out, which one would be the most effective? Why? If you are trying to fill the cylinders of your engine and you know that a high charge density is going to give you more power, are you going to want high velocity or low velocity ports?

It should be obvious, that flow is a matter of diminishing returns, when it comes to volume vs velocity. All ports reach a point at which any increase in valve lift, produces a minimal increase in flow until it approaches a zero return. In other words, with more lift, we get less velocity. This tells engine designers where the maximum effective valve lift is.


The higher the gas speeds, the better the air/fuel mixture is atomized.
Higher velocities typically improve the combustion chamber 'swirl' effect. The 'swirl' is needed to distribute the air/fuel mixture into the combustion chamber and aids in the creation of turbulence, also needed for complete combustion.


Can I run the ARCA head on my 2.9 project or would it be better running my ported head or buy an essy?
The ARCA head (made by Esslinger )would be nice. Do you have 6-8K for the head all the associated hardware? If so, yes get one!


Also anyone have any info on the Racer Walsh power heads?
They receive mild port and seat work from what I have seen, can’t seem to get any flow data from them.

[zonker]

OHC's concept car body double...

[Cgross609]

^^ aHAHAHA +1 For that. Good ol Chev berretta lol

[zonker]

Originally Posted by Cgross609 ^^ aHAHAHA +1 For that. Good ol Chev berretta lol

umm ford thunderbird mate...

cheeby beretta below:



i can see how u might think they're the same... but the t-bird is a real car, where the beretta is a pretend one.

[free2.3]

they all look like boobals to me

[free2.3]

oh and holy shit 8k for a head hahaha no fucking way thats retaaaarded hehe snozberrys taste like snozberrys

[ranger50toy]

I like the look of the SN95-Fox. Might be easier to put Fox sheetmetal on the SN95 Body.

[free2.3]

dude your talking about a roof graft compared to welding everything on differnt panels. just because a fox and sn95 have the same chassis the similarities stop there the sn95 id longer and wider with a different firewall hight and trunk hieght. youd be building a car instead of grafting on roof wich only requires 6 spots of welding compared to hundreds of hours of sheetmetal work

[OHC230]

"youd be building a car instead of grafting on roof which only requires 6 spots of welding compared to hundreds of hours of sheetmetal work"

I would agree here. The SN95 and Fox winshields are very close in terms of width and I was surprised to find that the distance between the front side windows of both cars, were within a fraction of each other as well. Since my car is a convertible, some of the work is all ready done.