Duratec / Mazda L-Series MZR I4 2.0 / 2.3 / 2.5 Swap
- DPDISXR4Ti
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Re: Duratec / Mazda L-Series MZR I4 2.0 / 2.3 / 2.5 Swap
Been thinking the 2.0 Duratec might be good enough for those not looking for a big power setup. One advantage is that the 2.0 block is about a 1/2" shorter than the 2.3/5 block, which might be helpful when fitting a MZR under a Merkur hood, Scorpio or XR.
The Focus would far and away be the most common 2.0 donor. You'd most likely want to be looking at the 2005 - 2011 Focus. The "new" 2012+ Focus is Direct Injection, which presents more challenges when swapped.
I had been under the impression that all the 2005-2011 2.0 Focus engines were the same, but it appears that may not be the case, as outlined here:
https://sbdmotorsport.co.uk/product/dur ... formation/
In short, the 2008+ heads have a high-port design which should flow a little better. The high port castings numbers are RF3S4G (AKA 3S4G) and RF6S4E (AKA 6S4E). The earlier (low port) head is the 1S7G. Note, this info comes from the UK and may or may not be exactly the same in the US.
The Focus would far and away be the most common 2.0 donor. You'd most likely want to be looking at the 2005 - 2011 Focus. The "new" 2012+ Focus is Direct Injection, which presents more challenges when swapped.
I had been under the impression that all the 2005-2011 2.0 Focus engines were the same, but it appears that may not be the case, as outlined here:
https://sbdmotorsport.co.uk/product/dur ... formation/
In short, the 2008+ heads have a high-port design which should flow a little better. The high port castings numbers are RF3S4G (AKA 3S4G) and RF6S4E (AKA 6S4E). The earlier (low port) head is the 1S7G. Note, this info comes from the UK and may or may not be exactly the same in the US.
Brad
Re: Duratec / Mazda L-Series MZR I4 2.0 / 2.3 / 2.5 Swap
In my head, I can't have an XR4ti without a 4 cylinder turbo. That is why I was thinking new duratec ecoboost...I am not sure of how the older versions would be turbocharged, I am sure it is possible, but more research. Please figure it out and let me know!DPDISXR4Ti wrote: ↑Mon Jan 23, 2023 3:10 pm Been thinking the 2.0 Duratec might be good enough for those not looking for a big power setup. One advantage is that the 2.0 block is about a 1/2" shorter than the 2.3/5 block, which might be helpful when fitting a MZR under a Merkur hood, Scorpio or XR.
The Focus would far and away be the most common 2.0 donor. You'd most likely want to be looking at the 2005 - 2011 Focus. The "new" 2012+ Focus is Direct Injection, which presents more challenges when swapped.
I had been under the impression that all the 2005-2011 2.0 Focus engines were the same, but it appears that may not be the case, as outlined here:
https://sbdmotorsport.co.uk/product/dur ... formation/
In short, the 2008+ heads have a high-port design which should flow a little better. The high port castings numbers are RF3S4G and RF6S4E. Note, this info comes from the UK and may or may not be exactly the same in the US.

- DPDISXR4Ti
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Re: Duratec / Mazda L-Series MZR I4 2.0 / 2.3 / 2.5 Swap
I get that. I'd be looking at the MZR swap into a Scorpio. Simplicity and reliability would be the paramount concerns given that my wife drives the car more than I do. As such, N/A it would be.
I haven't studied this much, but I think I've read that the stock 2.5 internals stands up to turbo-charging better than the 2.0 and 2.3. I'm not sure what the limits are, but I'd guess you could easily get to 250HP on an untouched junkyard engine just by bolting parts on and limiting boost to maybe 8 lbs.
Brad
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Re: Duratec / Mazda L-Series MZR I4 2.0 / 2.3 / 2.5 Swap
These guys make a bunch of different Individual Throttle Body (ITB) kits for the Duratec engine. You'd want to enclose them in some sort of filter/plenum that supplies cold air rather than hot under-hood air.
https://store.jenvey.co.uk/throttle-bod ... -ford-kits
https://store.jenvey.co.uk/throttle-bod ... -ford-kits
Brad
Re: Duratec / Mazda L-Series MZR I4 2.0 / 2.3 / 2.5 Swap
Back to transmission choices, wouldn't the Mustang SVO 5 sp work and be a better choice than a Ranger truck tranny? I would have to think that gearing and even the syncros would be set up for truck situations as opposed to quick shifts and off the line performance.
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Re: Duratec / Mazda L-Series MZR I4 2.0 / 2.3 / 2.5 Swap
Currently there is no bell available to mount a T-5 directly to the MZR. One did exist in the past from Quad4rods, and one may exist in the future, but today, no.
Brad
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Re: Duratec / Mazda L-Series MZR I4 2.0 / 2.3 / 2.5 Swap
Here's a China-cheap intake manifold...

https://m.alibaba.com/product/160050703 ... 00x200.jpg
It appears to be a knock-off of this one...

DESCRIPTION
New intake manifold from 1 Goal Performance. Fits 2.0L and 2.5L engines (setup for the larger port of the 2.5, but will work well with the 2.0 after you port match the head).
https://www.good-win-racing.com/Mazda-P ... -2510.html

https://m.alibaba.com/product/160050703 ... 00x200.jpg
It appears to be a knock-off of this one...

DESCRIPTION
New intake manifold from 1 Goal Performance. Fits 2.0L and 2.5L engines (setup for the larger port of the 2.5, but will work well with the 2.0 after you port match the head).
https://www.good-win-racing.com/Mazda-P ... -2510.html
Brad
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Re: Duratec / Mazda L-Series MZR I4 2.0 / 2.3 / 2.5 Swap
As I stumble across things I'll try to post them in this thread for reference. Here's a stock 2.0 Duratec fuel rail modified for 8AN fittings (SS fittings TIG-welded). That should make for an easier time when plumbing in custom fuel lines.
Brad
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Re: Duratec / Mazda L-Series MZR I4 2.0 / 2.3 / 2.5 Swap
From Rens in the Netherlands. Some mods to the oil pan and X-member to fit a 2.5 into a Sierra. I believe this is the Ranger pan. Keep in mind, the XR4Ti hood is bulged in the center where the Sierra is flat. That gives us some extra height under the hood and so these clearance mods might not be as necessary, especially if using the shorter 2.0 Duratec. I'm not sure how the Scorpio compares from a clearance standpoint. The hood is flatter like a Sierra, but the car bodies are obviously different. On either car, spacing down the sub-frame is always an option as is done on most V8 conversions.
https://www.amazon.com/Premium-Engine-F ... B07PMNBHN7
I'm not saying for sure it fits as-is, but it looks like it could.
I'm updating my comments to this post to indicate that I'm now pretty sure this ^^^ is NOT a Ranger oil pan. Pic below is of a Ranger oil pan, which you can see, is pretty flat on the forward section.
You can buy this pan new for $70.99 on eBayhttps://www.amazon.com/Premium-Engine-F ... B07PMNBHN7
I'm not saying for sure it fits as-is, but it looks like it could.
Brad
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Re: Duratec / Mazda L-Series MZR I4 2.0 / 2.3 / 2.5 Swap
Back to the discussion of a T-5 bell for the Duratec, Dellow Conversions in Austalia does make one, but it is for the Falcon-spec T-5 which has an input shaft length of about 6.5".
https://dellowconversions.com.au/produc ... -t5-trans/
Compare that to the Mustang-spec T-5's we typically use:
Fox body V8 - 7.18"
Fox body 2.3 - 7.41"
SN95 - 7.85"
Tim is working on an adapter to use a T-9 bell with a T-5. Although it's not his focus, it might work with the Duratec T-9 bells.
https://dellowconversions.com.au/produc ... -t5-trans/
Compare that to the Mustang-spec T-5's we typically use:
Fox body V8 - 7.18"
Fox body 2.3 - 7.41"
SN95 - 7.85"
Tim is working on an adapter to use a T-9 bell with a T-5. Although it's not his focus, it might work with the Duratec T-9 bells.
Brad
Re: Duratec / Mazda L-Series MZR I4 2.0 / 2.3 / 2.5 Swap
I'll jump in on this:DPDISXR4Ti wrote: ↑Fri Mar 24, 2023 11:41 am Back to the discussion of a T-5 bell for the Duratec, Dellow Conversions in Austalia does make one, but it is for the Falcon-spec T-5 which has an input shaft length of about 6.5".
https://dellowconversions.com.au/produc ... -t5-trans/
Compare that to the Mustang-spec T-5's we typically use:
Fox body V8 - 7.18"
Fox body 2.3 - 7.41"
SN95 - 7.85"
Tim is working on an adapter to use a T-9 bell with a T-5. Although it's not his focus, it might work with the Duratec T-9 bells.
THe Dellow conversion Bell, like as said, has the 6.5" input shaft depth. Lucky for us, the GM input shaft is that exact length and utilizes a 15mm pilot, just like all the Ford 4 cylinder engines (Duratec and Ecoboost included). It's 2.95 only (oh, no, use Cosworth gearing...). It's around $585 with the conversion rate and you'll look at close to $200 to ship one to your door here in the states. Not exactly the most cost effective, but definitely an option.
If you feel like selling a kidney or something, the Quicktime bell utilizes the Fox clutch fork. Spend wisely. I don't like it much, but it's an option.
RWD motorsport does have a Duratec/EB to W50/58 series from Toyota. Decent ratios and good strength.
RWD motorsport also has the Duratec/EB to T9 that is a 173mm depth. The end of the pilot on the 4cyl T5 sits flush with the face of the bell, so that was a great measurement for me. The goal is to get good pilot engagement, so that gives few mm of play. The Ford Fox input is 183mm, so that's a 10mm difference. Having a 5mm recess might still allow for good engagement on the pilot, but I don't know on the Duratec or Ecoboost. I'd hate to go thinner due to hardware interference with the bore of the T9 and thread engagement for the mounting bolts. The RWD motorsport bell is under $300 US, so that might actually be a great starting point and I might just purchase one. If going to the SN95 input length, that would be a 26mm thick spacer, which would be easily doable. Luckily, the T9 uses the same size snout for the throwout bearing, so you can use that clutch fork setup, but it's on the "wrong" side for us here in the states (requires a longer clutch cable routed around). If the bellhousing is thick enough, might be able to just face it down a few mm.
I am currently developing US T9 to T5 adapter plates, which will be 15mm thick (add 6mm to engage into the bearing retainer hole to center the plate). I don't know the difference between the different T9 bellhousings, but I made it to fit the SN95 input shaft length. Optimal depth is in the 12mm range, but need the extra 3mm to clear the bearing retainer hardware and get good thread engagement for the mounting bolts. THis is an option. Another option is to get the T9 bell hole bored open and run the Modern Driveline spacer (18mm thickness) with the T9 pattern drilled into it. Price of that will likely rival the Dellow bell shipped though.
I do have another option I've thought about, which is using the NC Miata Automatic bellhousing with an adapter plate. That will be Hydraulic only though. I have drawings for LS T56 and a dual pattern Ford T5 and Muncie with GM depth to utilize any Muncie trans: TKX/TKO, Jerico, G-Force, etc. T5 will be 2.95 only (or G-Force 2.41 1st). Need to finalize the bore and bolt pattern for the automatic trans to bell to ensure it's centered.
If anyone has any measurements of the depth of the different conversion bellhousings for certain types of T9s, I'm all ears.
Tim Spencer
1988 XR4Ti Duratec project car
2011 Taurus SHO daily driver...not stock.
1988 XR4Ti Duratec project car
2011 Taurus SHO daily driver...not stock.
Re: Duratec / Mazda L-Series MZR I4 2.0 / 2.3 / 2.5 Swap
Lots to read.. this may be a silly question but would the exhaust valves in the Mazda 2.0, 2.3 and 2.5 engines be the same? Thanks.
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Re: Duratec / Mazda L-Series MZR I4 2.0 / 2.3 / 2.5 Swap
A quick search would seem to indicate that the intake and exhaust valves are the same across all 3 displacements. I'm not sure if the factory turbocharged engines use different valves, but I imagine the dims are the same.
Brad