View Full Version : Detuned?
OK, I've heard several times that the Duratec is tuned down from what it could be producing, as to "not step on the Mustang's toes". How EXACTLY does Ford take the Duratec and rob it of power? I was just wondering.
Andy
Grav1ty
04-02-2001, 11:31 AM
compression, cams, reduce size of intake and exhaust. and im sure there is lots of things i dont know about too.
as car and driver says...
2-ton flywheel i/expressions/smile.gif
PuckPuck
04-02-2001, 12:17 PM
a highly restrictive heads/intake....
i don't know why people don't get this... but most power in an engine is realized in the heads/intake manifolds.... the lower end is really only modified to allow for more strenght and life of the engine. Let's for example take a racing circuit called Nascar. All teams must use a factory block and can't be beyond 351 (or 355) ci of displacement. The carburators and ignition systems are regulated, so are a few other parts such as vavle sizes, piston and rod materials and such.... what is not regulated however is the head/intake design. This is where engine builders will keep all their secrets. With a good set of heads you can gain 50%+ out of an engine. A highly tuned non-street car can double it's horsepower with a good head work. This is also where the duratec is restricted. Funny thing is a 2.5L V6 duratec will be going in the jaguar with 220HP... same engine as we have with 50 more horses... go figure.
want more examples... a 2.5L duratec was build up buy some renowed engine builder called Duttweiler (sp?). With a turbo at 21lbs (or 26) of boost they got 450HP. stock was 200HP (they used an SVT version)... what an SVT has over us is cams, and larger intake, tb and such (head work again here)... anyhow the extra 250HP is coming from where?!?!?! well the turbo should be responsible for about 150-200HP of that and that's granting they used a real good turbo. The other 50 + 30 (the 30 is the SVT over us) comes from head/intake work... they netter 80HP from redoing the upper engine... maybe more....
Things to note... this 450HP duratec used an SVT intake, heads, cams, TB, and injectors, custom turbo (forgot the name of the make) and custom headers for the turbo. Since they were pumping so hard they also rebuilt the lower end with better rods, pistons, pins and rings - but did not bore or stroke the engine. THe valves stayed stock.... and there was extensive Duttweiler secret head porting and polishing done.
sorry for the long post but i was just discussing this with a co-worker and though i would share it with you.
Frank
04-02-2001, 12:20 PM
So who's gonna be the first to have their heads ported and polished?
Merc123
04-02-2001, 01:18 PM
ME ME ME! Planned on it. BTW, did you know there are like 1800 catalytic converters on our car? A mechanic pointed it out to me when it was on the lift
Frank
04-02-2001, 03:14 PM
Yeah, the main one probably saps 6-8hp, and the two precats probably combine for another 8. EPA overkill.... methinks yes. Especially on a new car.
PuckPuck
04-02-2001, 03:28 PM
the main cat does not suck 6-8hp... maybe more like 1-2 and the other cats wouldn't even suck .5hp from you.
stupid question..
What are HEADS...
the parts of the engine i know are upper and lower intake manifold, cams, block, headERS... etc.... but whats a head?
Also called a cylinder head, the head sits on top of the engine block. Being a V6, the Duratec has two- One over each bank of three cylinders. It basically covers the pistons, and is where the valves, spark plug, and cams reside. Big part of the engine. The heads are responsible for getting air into the combustion chamber, igniting the mixture, and purging the exhaust gases. Any inefficiencies in this process technically rob you of horsepower. The stock Duratec is meant to be a daily driver engine, not a BTCC engine. Leo Capaldi did TONS of work to his SVT spec motor and is pushing 300 normally aspirated horsepower. Granted, this is on racing fuel and 13.0:1 compression. Port & polish, lightened flywheel, forged crank, titanium pistons & rods, custom cam grind- The works.
Hope this helps,
Merc123
04-02-2001, 04:25 PM
If i'm not mistaken, the heads are those thing that make up a piston..the top part of them.
MaStaMooN
04-02-2001, 04:25 PM
Heads sit on top of the cylinders and usually contain the intake/exhaust valves and such. Your lower intake manifold bolts to these for air input. Headers bolt to the exhaust ports of the heads to get rid of the exhaust produced in combustion. Unless you have a flat head engine, then the valves are in the block itself, along with the exhaust ports... Anybody see popular hot rodding magazine this weekend??!!
Edit: Geez, 2 people answered while I was typing..lol
DeadPurple
04-02-2001, 05:07 PM
Ive already had mine port and polished. I did it about 9 months ago.
FastCougar
04-02-2001, 05:25 PM
DeadPurple,
Who did it? How much did it cost? What where the gains? Are you satisfied?
I have a million more question ... just can't think of them right now.
Frank
04-02-2001, 08:04 PM
Actually, now that I double-checked, Terry Haines claims that gutting the pre-cats increases horsepower 10-14% on the dyno.
http://contour.org/forums/Forum6/HTML/001048.html
HangTime
04-02-2001, 10:19 PM
Sounds to me then that most of the gains from the MSDS headers are in removing the pre-cats... if Terry is correct.
mransr
04-02-2001, 11:34 PM
17 to 24hp by gutting the cats??????? seems like an awful lot....
There's a dyno plot out there of a stock 2.5L V6 before and after intake, MSDS, and BORLA. 30-35hp gain to the wheels..... There's definatelyt some elapsed time between the 2 runs (check the date)...but it still shows quite the gain.
Here it is (http://www.spmotorsports.com/contour_exhaust_msds_dyno.html)
Raphun
04-03-2001, 12:05 AM
My question about the heads, is could we take the SVT heads and put them on top of the our duratecs. If I'm not mistaken the SVT stuff that some people have done is just the upper and lower manifold? I'm wondering because I've seen pictures on DanG's webpage of some SVT stuff on his motor. That is just the SVT upper and lower manifolds, right Dan? So, if the heads from the SVT would work, what would it take to actually get them on there? I mean would you also need to then buy the SVT ECU so all the fuel mix and timing is correct? Has anyone done this mod BTW? It seems like think Purrt was saying up above that this would make us a lot of HP. I know my mustang buddies rave about ported and polished heads.
exigent
04-03-2001, 01:15 AM
puckpuck, Terry H. over on the contour board says 10% or more hp is locked up in those precats. He says while at ford they cut a set of stock manifolds, removed the matrix, and welded them back together. He says that the 10% number was verified on an an engine dyno iirc. Either way... alot of folks dont believe that those precats muck up power, still others say that it will actually hurt perf. if you just gut them and leave the "expansion chamber" style manifold there. When a Ford engineer who was part of the devopment of the Duratec claims somthing however I listen. Several folks over at CEG have done it. Im not aware of any dynographs... I do however know that that guy with the cougar who dynoed with the CEG that day and made 180 to the wheels when svt's where putting out 173 or less had "european" as he called them... catless manifolds. HRmmm... this makes me think back to folks claiming the svt tb does nothing at all without the svt upper intake, dispite a dynograph on the CEG showing a 5hp gain. I dunno what im trying to say exactly except more inter board co-op would be nice. Each of us have our own little theorys and stupid myths (like svt tb and t/c) and stuff like that. They have already tackled alot of issues at CEG and we can learn alot over there. I would also say the taurus folks could teach us too... but the majority of people there are set on swaping out the Duratec for a vulcan crate so they can get a roots blower... jeeze Ive never seen so much ignorence as on that board. They posted a pic of a 2.5L upper manifold from a duratec(ours) and then they were like "YEH thats that new manifold that is supposed to add like 50hp to our cars!!!" I sent them a few pics of mine and other cougars & svts and made a couple of folks really mad... phew its late and im ranting.
sorry.
PuckPuck
04-03-2001, 11:27 AM
10% from removing the pre-cats..... WOWOW is all i can say....
as for doing the heads.... i have been talking with a local race engine builder about this since november.... he seems very interested and has done some research on his own for my motor... i passed him the article on the 450HP duratec from duttweiler and he claimed he could get me closer to 60HP just from head work.... maybe more, the only way he could really tell is by looking inside them, of course he also said that if you start doing that kind of HP, you'll need better pistons, rings, rods and pins too. not to mention the trans problems that will come about.... also i'm starting to go through junk yards to find any mystique, contour or cougar with a duratec in it.... i may also just go with a 3.0 after and only after it has been proven to me that it will fit and that the 2.5L heads can be mated succesfully.
Raphun:
The heads are a bit of a mystery. The SVT engine has higher compression than a stock Duratec, which leads me to think there may be a few differences in the heads- Dish size, or "squish area", or the piston heads may be different, or both. The SVT intake I have is just the upper manifold and TB, where the most increase is gained. The lower manifold supposedly increases the intake bore by 2mm, but I'm not sure how much power that will realize over stock, since the stock lower manifold is already polished at the secondaries.
So will it work? Maybe. Do you want to be the one that finds out that your pistons just smacked and broke half of your valves? Not I.
I guess the only way to make absolute sure is to also pull a set of SVT pistons, rods, and crank to make sure the stroke is exactly what the SVT heads are expecting. Sounds too pricy when you can get a whole SVT motor from a junkyard for $1400...
Hope this helps,
CougarRacer
04-04-2001, 12:54 AM
So what would it take to put one of those Jag engines into our cars?
Racer:
I wouldn't bother. The money it's going to cost you to actually get a hold of one of those engines is going to be silly when you can get an entire SVT motor, mod it, and throw it back into your car for cheaper! The Jag engines may also have other incompatibilities we're not aware of. Anyone seen one?
PuckPuck
04-04-2001, 11:00 AM
they are unloading a bunch of cars into my parking lot and occasionally they have jags.... next time i see jags if they have the X-type (the one we are refereing to) i'll kindly ask the guy to pop the hood and i'll let you all know what i can find out
Raphun
04-04-2001, 12:30 PM
Let's say for a moment that one bought an SVT motor, what exactly would you do to it first. It already has the free flowing intake minus the the KKM which you could through on there no problem. Good headers it has, so besides an SC what would yall do?
PuckPuck
04-04-2001, 12:58 PM
port and polish the heads/intakes
That, headers, a 5 angle valve job, molybdinum rings, upgraded oil pump, oil baffles, forged crank, titanium rods, bore the cylinders and install higher displacement sleeves (gets you above 3.0L), higher compression pistons... You'd be just about where Leo Capaldi is- 300hp at the crank. You'd scatter your transaxle in about 3 seconds flat, but it would be one helluva ride.
CougarRacer
04-04-2001, 09:59 PM
I called a Jag Dealership today and they said the Jag engine put out about 193. If you have other information, please let me know. Thanks