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Sückn' n Blown
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What do you mean longer rod? Are you using a custom piston that is smaller in size? Because a longer rod will just cause the piston to hit the cylinder head.
 

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Discussion Starter #3
Sorry didnt make my self clear the rods in the 2.3 engine are 10mm longer than the 2.0l engine has any body ever tryed to fit them with the likes of a slipper piston or fit a 2.0l crank in a 2.3 engine and machine the top of the block to make use of the longer rods
 

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w/ my magic bag
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Lot of work for the return you'd get.

Sorry didnt make my self clear the rods in the 2.3 engine are 10mm longer than the 2.0l engine has any body ever tried to fit them with the likes of a slipper piston or fit a 2.0l crank in a 2.3 engine and machine the top of the block to make use of the longer rods
That is a lot of work for what you'd get in return. Why not just start out w/ a 23 to begin w/? Unless you have 20, than I'd add a 23 head to that. I now the rod to stroke ratio isn't the greatest in a 23, but look at the 454 chevy's, rod to stroke ratio not great but they run super strong.
 

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Discussion Starter #6
Longer rods make a engine run a lot sweeter i just thought with so mant parts that are common to both engine that u could mess about a bit As for the heads i thought the heads were all the same are u saying that the 2.3l engine has a better head also there is a high port head option as well and a us spec head that suppose to flow really well sorry for all the questions but i am a rookie
 

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Yes, the 2.3l has a better flowing head. If you were to look at the two heads side by side, you would see that the 2.3l cylinder head has bigger ports.
 

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w/ my magic bag
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Do a 23 head on a 20, or go w/ a 23.

Longer rods make a engine run a lot sweeter i just thought with so mant parts that are common to both engine that u could mess about a bit As for the heads i thought the heads were all the same are u saying that the 2.3l engine has a better head also there is a high port head option as well and a us spec head that suppose to flow really well sorry for all the questions but i am a rookie
The 20 & the 23 motor's are very similar. Nothing really to mix & match, but 23 head's on the 20 & that's it. The 23's have balance shaft's, cause being a big 4 cylinder motor, Nissan's QR25= spec-V 2.5L has them too. But you take them out & plug the oil feed to the Balance shaft's & your motor has less rotating weight & hold's 6 qtr's of oil. So do a 23 or add a 23 head to your 20 motor. Waste of time= mixing rod's/ crank's/ piston's. Your over there, check out what the Caterham guy's are running! I know they have their motor, North & south, instead of east/west=FWD, but they would run the same setup thou.
 

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I think he is referring to the aftermarket high flow head from Cosworth and a few other manufactures.

They are basically 2.3 heads that have been ported for maximum possible flow, however how much better no one really knows. Also anyone who is using F/I probably won’t get as much of a benefit from them since the 2.3 head already flows pretty good. I think they are more for NA high compression engines.
 

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Discussion Starter #11
THE DURATEC

Steve Broughton's inital reservations about the Duratec engine centred on the lubrication system and the hydraulic cam chain tensioner: 'The oil return has been a bit of a problem, so we did some modifications to overcome that. And we also developed a new cam tensioner, too. Subsequently, we have seen no oil pressure fluctuations and minimal wear.'

But the Duratec's well-known strengths include significantly lower weight than the XE (95kg compared to over 110kg), a fundamentally good head design and a larger bore size (87.5mm compared to 86mm). This, together with its pent roof combustion chamber design, allows decent size valves, the standard sizes being 35.5mm inlet and 29.9mm exhaust. So for 2007 SBD started out developing a strong, reliable Duratec, initially using the standard crankshaft but with steel conrods, 'pot type' pistons and bigger throttle bodies fitted with eight injectors, four upper and four lower for improved fuel dispersion. With what Steve Broughton called 'a sensible camshaft and just a little CNC head and port work' this produced 283bhp and 192lb.ft.

'Then,' continued Broughton, 'Ford produced a new head in the USA that allowed 10 per cent greater flow. We put in 1mm bigger valves and fitted this. And with no other changes at all, the engine produced 304bhp and 195lb.ft (see figure 2, Duratec TP300+bhp kit ). It pulled from 1000rpm on full throttle, it was smooth and there were no bottom end losses.' and this was still mild cams. Running with just four lower injectors only dropped the power by 10bhp, which was still impressive and ahead of the XE.

Given the efficacy of SBD's cam profiles on the GM unit, the logical next step was to apply this principle to the Duratec. So new cams were designed based on the shorter duration, high-lift ones that worked so well in the XE. To considerable consternation through, the result was 4bhp less and 10lb.ft less torque. Broughton: 'The engine peaked 300rpm later, made less torque from 4000rpm, and only made the power it did because it revved more. It shouldn't have suffered a loss with the increased lift though, suggesting the duration is just too short for this engine. The fact that it peaked later is odd too. And that's where we are now [in April 2008]. The next step is some slipper pistons with smaller valve pockets and cam profiles that will combine the original duration with the lift of the cam that didn't quite work.'

Having already produced a 2.0-litre engine generating over 300bhp is no mean achievement, and to publicly admit a backward step in development emphasises Broughton's determination (and confidence) that yet more performance is still to be obtained from the Duratec.

thought this would be usefull
 

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w/ my magic bag
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Wish more people over here= USA, were doing more work on the dura-tec motor's!
 

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Focal Distortion
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300bhp 2.0L!!!!!! wow that's making some power.
 

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Sückn' n Blown
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great info gaz, duratec tuners abroad are making headway with these motors...unlike us.
The majority of the engine work done over there is usually applied to Caterhams, Locosts, and other project cars, where they are not constrained to a FWD packaging, and allows them to run ITBs and long tube headers with ease, while not having to worry about emissions and streetability.

The market in the states for an 8500 RPM NA Duratec is much smaller, since the majority of buyers are for street-driven FWD cars, and as such, tuners focus their efforts to the market demands, which usually tends to be either bolt-ons or turbo kits.
 

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I do a LOT of the duratec stuff , I build engines for the Mazda Turbo cars , Caterhams etc
I have no problem building about anything any one wanted for the Duratec we have built dozens of them already

Tom
 

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br/o/stang
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5,563 Posts
I do a LOT of the duratec stuff , I build engines for the Mazda Turbo cars , Caterhams etc
I have no problem building about anything any one wanted for the Duratec we have built dozens of them already

Tom
Do you have any examples you could share? This is def the path I want to head down (built all motor focus) and finished builds are few and far between on here. Would love to see a few examples of "these parts + these assembly tricks got us this result". 2.0 or 2.3, either or as long as its N/A

[clap]
 

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I do a LOT of the duratec stuff , I build engines for the Mazda Turbo cars , Caterhams etc
I have no problem building about anything any one wanted for the Duratec we have built dozens of them already

Tom
You are probably an exception to that, but you don't see many tuners pumping out big HP all motor duratecs over here.
 

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Thats true but mostly because they dont want to spend the money to build them

Focus guys are tight , Caterham guys will spend the money more

Tom
 

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br/o/stang
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Once a focus guy has enough to do something like this they wind up ditching the platform for something "better". Thats why we have a bunch of people focusing on boltons and easy stuff as they work their way up
 
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