View Full Version : question on the dual sparkplug head

11-11-2009, 06:23 PM
I have searched, but cant seem to find any real info...is there any advantage to swapping to one of these heads? i know they make more power in NA form, and the dual sparkplug setup appeals to me for other reasons...I guess I should ask...is there any reason I couldnt use one of these heads? any exhaust/intake port differences? different piston reliefs? etc etc, I'm planning on building a Folvo head engine on the side...but this would be interesting for different reasons(it would also get a standalone ECU at the same type and the distributor would go)

11-12-2009, 04:38 AM

Seems like a pertty pointed group - states if you are looking for info on NA engines go somewhere else.


11-12-2009, 11:27 AM
Ok let me re-iterate the obvious, my question was on using the more efficient dual plug head on the 2.3T block. I'm not stupid I know its a NA head but that makes no difference as far as the engine is concerned, my question is whether it has been done, the question is more relevant to a group more likely to see it as a performance upgrade since NA guys wouldnt be likely to do it at all. Combustion chamber volume difference would be nice to know as well

11-12-2009, 12:44 PM
Sorry I found that LINK (did you join the group and see what they offer for info?) and posted it.

LOOKS like the place to get info (if you want to go that way) The only SVO head change I've done is either Big Valve Iron (street cars) or Esslinger ARCA (on the race car).

As for differances
Turbo Head 1984-86 No air holes in exhaust ports. Open chambers, D shaped intake ports. Valvesprings are heavier and the exhaust valves are made of an inconel material to withstand the increased heat of the turbocharged engine.

Ranger Head 89/mustang 91 "Dual Plug" head, with 2 spark plugs per chamber. The first major redesign of the 2.3 lima head since the original pinto debut. Intake ports have a massive swirl dam in the bowl area to induce swirl for cleaner emissions and low speed torque. The intake ports are a smaller version of the "D" shape, however they are symmetrical as opposed to angled different directions like the early heads. The ports themselves are much smaller in diameter for high velocity low speed power. The intake bolt pattern is different from the early heads as well, manifolds will not interchange. The combustion chambers were redesigned as well for a higher swirl and faster burn. The exhaust port is identical however in location and bolt pattern. These heads all came with roller cams. No smog holes in the EX ports. Typical casting #'s E89E-AB, E97E-BA

There is a latter DP head but it too "raises" the compression on a SVO - which I never consider/seem to try to go down and UP in boost on builds. Another "Search" produced this for you. http://www.turboford.net/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=2;t=040342

P.S. I did have a Zackspeed DOHC once , but I figure that isn't even in the rhelm of life today. Ford bought them all back for the English Focus Drag Racing Series in the late 90's.

11-13-2009, 03:48 AM
thank you, according to that thread, the early dual plug head outflows the turbo head quite impressively..enough to be worth swapping to stock for stock, the reason the dual plug head fascinates me though is because its possible to use that head in a hydrogen engine and possibly stil be able to have it turbocharged with lowish boost(on a ges 15psi or so) I have been playing with the idea of building a hydrogen combustin engine over the last couple of years as the technology for efficient and safe hydrogen storage is finally coming out(you can get a 400 mile range from a decent sized tank)s

11-13-2009, 06:18 AM
It is a flow chart comparison from "cam/head expert".

If you devise an intake , lower the compression (I add .5 mm to the dish) and purchase better valves you could use it .

11-13-2009, 02:25 PM
I have personally built turbo engines at 9:1 compression running 20psi without issues, other people have done turbo 12:1 CR engines @25psi...running e85...(crazy people)

the engines i built were 2.4L DOHC chrysler engines with standard valves...which again turned out not to be an issue, even the valvespring seat pressure(60psi) shouldnt be an issue, its the same as the chrysler engine...not saying that the engine wouldnt benefit from those modifications, just that they arent strictly necessary...I think i am going to attempt the swap with an unported, stock valve, stock spring head using a late model intake manifold just to see what real gains there are(I'll dyno if I do this) to get some concrete numbers....I will be getting rid of the distributor and running megasuirt...however for the test I will keep fuel trim and timing stock, as well as keeping the VAM attached, the only variables in the setup will be the intake manifold and head(to begin with) then I will remove the VAM and dyno again, I also plan on a sheetmetal intake manifold to make a larger plenum and shorter runners, another dyno run after that....and finally I will advance the timing as much as I can without detonation(the threshold should presumably be raised a bit with the dual plug head from what I have read) and dyno tune the thing, in other words I'll do the testing and get some solid numbers out there on the max I can squeeze out of a basically stock engine with a dual plug swap

11-17-2009, 05:49 PM
Yeah you can do anything with fuel management of "today" provided you spend the money.

I'm not the person to ask about 'modding" - when I was racing SVO's the only thing available as a "stand alone" was a Dr. Gas unit !

P.S. Today , I only have stock SVO's (even my 3000GT VR4 Spyder is stock) !
SO many "tuners" tell me "you need a HKS this" and "you can up the boost" ....

I'm like "The car weighs almost 4000lbs !" Why would I mod that !