When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
NAM this is Ollie, my recently acquired 2014 S. Ollie say hi to NAM. "Beep beep". Ollie sounds friendly enough but he's hiding something...
Ollie just looks like a really well sorted Mini. He's loaded with all the options you could want, has 20,000 original miles, 3,000 miles on the new engine, is lowered on a set of BC's with wheel flares, staggered Enkie rims 18x9 up front and 18x10 in the rear, JCW brakes, HK lower trailing arms, poly bushings and a custom 3" exhaust that sounds perfect IMHO. I did however allude to the fact that he is hiding something. Specifically this...
Here's a bit of the backstory to this car. Until recently it belonged to the original owner that became a client of mine when I tuned it back in 2018 or 2019. He's a great guy and having known him all this time I consider him a friend as well. The car itself has been very well maintained and garage kept since new. It was originally an automatic and had a fair amount of fabrication work done locally in order to install a Garrett 2871 w/0.64 Tial housing and was subsequently tuned by a tuner out of the EU. It ran 19 lbs of boost and I believe it made around 295 to the wheel at the time. Boost control was via a Tial external wastegate with GFB controller and the Tial BOV is controlled by a Turbosmart BOV controller. Unfortunately, traction was a real problem and once moving where it could get traction... well lets just say the automatic wasn't long for this world. Not content with turning it down and keeping it an automatic, the owner decided to have a forged motor built and a manual transmission installed. Once all that was done he contacted me about programming the car for the conversion and re-tuning it. The builder that did the transmission swap and built the motor had some short comings shall we say when it comes to understanding F platform integration, the limitations of DI and the transmission as well. Before reprogramming it was necessary to have the wire harness updated and the zero gear switch installed. I guess he didn't think that part was important lol. In addition, the automatic trans pedal had to be replaced due to the kickdown notch. The builder installed a custom made twin disc that was made here in the US, a Quaife LSD and a Tilton hydraulic throw out bearing to replace the Mini slave unit at the same time. Once all the changes were completed, I reprogrammed the car and re-tuned it. Issues at the time were a compression ratio that at 11.5:1 was way too high and come to find out rods that were a tiny bit short in length since no one made forged rods for the B48 at that time. The builder had hoped that E85 could be used with addition of the surge tank and Bosch 044 pump. The Bosch 044 pump however is not a high pressure pump. In addition, it has no check valve to keep the fuel line pressurized. After a spirited drive, shutting off the car would result in it vapor locking which is when the carbon hood vents got added. The GFB boost controller was replaced with a Cortex EBC for boost control by gear and also to allow a finer degree of boost control by rpm. An Aquamist HFS4 was added and power output climbed to 330-340 HP. However, the car would break up if boost climbed over 20 psi above 5,200 rpm. Boost could be peaked at 24-25 at lower rpm but had to be rapidly reduced in order not to cross the 19-20 psi range up top. Needless to say the thing was a torque monster.
Shortly thereafter the twin disc started slipping and I was again consulted. The owner followed my suggestion and went with a TTV Racing single which it still has. That transmission wasn't long for this world either. The front of the Mini transmission case is not designed to handle the thrust load in that area of the case. So case flex caused the reverse fork to break. The Tilton was removed, a standard Mini slave unit installed and Mr. Transmission is all happy again.
Recently, another engine was built. This time by the owner himself with some sage advice from his wise tuner . New engine has 10.2:1 Supertech pistons, H-Beam rods and Supertech valve springs and titanium retainers. Other than springs and retainer the head is stock and everything is held together with ARP studs. Here's the first built motor coming out.
Fresh ceramic coating on the exhaust header.
Supertech goodies.
Aquamist 10L tank in the boot.
It had some issues following the new engine install. Specifically, the boost control was super touchy. A few percentage point of too much duty cycle and it wanted to race to 25+ psi. In addition the meth controller had developed an issue. Around this time the original owner got bitten by the new BMW M2 bug and called ask if I would be interested in taking on the project. He felt anyone else wouldn't have a clue where to begin with something like this and he knew it would be well taken care of.
So that's how Ollie came to find a new home. Right off the bat I re-tuned it with a non-meth file. Boost control turned out to be the boost solenoid. So a new 3 way MAC solenoid was installed and boost control was restored. Trouble shooting of the Aquamist revealed the problem was internal to the controller itself. Performed a smoke check and found the original fabricator misjudged the correct diameter for the PCV fitting resulting in a leak and had a massive air leak at the MAF sensor housing. It was supposedly smoke checked by the original engine builder but I guess he forgot his glasses that day. As a temporary solution, the MAF housing was cut from the intake plumbing and an Eventuri unit installed.
A subsequent review of data on the Tial housings with lower AR on small frame Garretts indicated a problem with choke flow in the housing itself. Additionally, putting this engines into the Garrett boost adviser indicated the 2871 was actually a poor choice. I'll cover more of that in the next post.
List of things on my to-do list.
1. Remover oversized intake plumbing and replace with 3" pipe.
2. Eliminate additional vacuum leaks.
3. Replace Aquamist HFS4 controller with a new unit. (ordered)
4. Switch from single port meth injection to direct port setup. (received)
5. Replace GT2871 with a different turbo. (ordered) Can you guess what brand?
6. Replace the Tial wastegate with a Turbosmart. (received)
7. Replace Tial BOV with Turbosmart SuperSonic. (ordered)
8. Replace hood with VIS Racing carbon hood.
9. Install carbon front splitter.
So in the previous post I mentioned the 2871 not being a very good choice for this engine. Combining a 0.64 housing with a rams horn manifold is a bit like using a long duration cam with an intake manifold with short runners. Will it work? Yes, but the two do not compliment each other. With this style exhaust manifold, a 0.80 housing is more in line with what you would expect to see. Add in the fact that the smaller AR Tial housings trades flow for spool even over the same sized Garrett housings and you have a pretty good recipe for really high back pressure. Too much of that and the exhaust pressure in the manifold will revert into the combustion chamber driving up temps and contaminating the intake charge. Additionally, with a goal of 41 lbs/min and punching the numbers into the Garrett boost adviser this is what you get. Anytime you're on the wrong side of the surge line it's not a good place to be and 39 lbs/min doesn't occur till 2.2 bar of boost.
My initial thought was to go with a GTX2867R with 0.80 Tial housing. This would allow me to use all the existing plumbing, reduce back pressure and perhaps make up some of the spool difference with the smaller compressor wheel. It's a good 7 lbs/min or 70 HP away from the surge line. This wasn't bad but the turbos best flow is at about 48 lbs/min at 1.6 bar. At higher boost it actually flows less. Also note you have to spin the turbo at 158,000 rpm to get there. Accelerating the wheels takes time.
My next thought was the heck with the plumbing what about the G25-550. Much smaller wheels and better aero. Lets see what that looks like.
Surge line is still good. We're about 7 lbs/min away again but gahh we have to go to higher boost and we're still not getting 41 lbs/min with the smaller wheel, plus we're at about 170,000 rpm. I'm not even going to get into that new math Garrett is using to get to 550 hp on 49 lbs/min of air. Feel free to look for someone making that much on-line.
I could show you the same number on the G25-660. Surge line is still great but there will be a lot left on the table and it just adds more lag. This is not intended to be a dyno queen. A front wheel drive car's sweet spot is about 350 WHP. Beyond that it just gets scary. I won't complain if it gets to 400 but I guarantee you the boost profile I'll be running on it daily will ensure its lower than that. About this time I was feeling a bit depressed and then I remembered Xona Rotor which is a joint project between Forced Performance and Tial. I looked at them a few years ago for the R56 but didn't feel anything they offered would be a good fit. Hmm.. lets set what the numbers look like on a XR4951S.
The majority of the time it's right in the compressor sweet spot. Plenty of distance to the surge line and hitting 41 lbs/min at 135,000 rpm. Add in the fact that the turbine wheel is much larger at 57 x 51mm and that this model now includes the UHF turbine wheel and the reduction in back pressure might just make the 0.63 housing a viable option.
So now you know the reason for the thread title. I haven't seen this turbo used on a Mini previously so hopefully this will turn out to be interesting... in a good way.
6 x 6, 12 blade compressor wheel which explains the improved efficiency at higher pressure ratios. Less wheel slip.
Billet stainless steel center housing with dual ceramic ball bearing assemblies.
And of course the 10 blade UHF turbine wheel that reduces the height of every other blade to reduce weight and increase flow.
The Xona also has the advantage of having the exact same size connections as the Tial housing currently on the 2871.
Again, beautiful looking stuff ! You have way too many toys. I can't wait to get you to play with Blue and Pepper ( my two ):
My first hint was the third photo and exhaust. Given you seem to have everything from the engine planned and sorted - a few questions from the exhaust manifold back. What size exhaust are you running ? Downpipe size and cat type ? Also - do you plan to ceramic coat the manifold and use a wrap or blanket on the hot side of the turbo and downpipe. Seems to be a lot of history about the importance of keeping the heat in the piping from turbo down for best performance and tuning ...
Yeah for the longest time I wasn't planning on an F56. Recently however I started getting an itch and almost pulled the trigger on a 2018 JCW. Then I was leaning towards a new build when this one came up. So I guess it was meant to be. If you look at picture 5 you can see part of the extra heat shielding on the right hand side of the engine above the wastegate. You can also see part of it in pictures 12 underneath the intake pipe.
Cat? What cat? Tabby, Tuxedo. Nope, no cats in the house anymore
The manifold is already ceramic coated. No wrap at this point but when the Xona goes in, the turbo and the wastegate are getting heat blankets. I'll decide if I want to wrap the manifold at that point but it would be a bit of a PITA. The intake pipes and heat shield would have to come off and it would have to be wrapped from above then completed from underneath.
The exhaust is 3" from the turbo back with a Vibrant back box and resonator. Not the best pic in the world. I'll try to get something better later and maybe a vid with the GoPro on the sound. I like a lot of burble without a lot of pops when tootling around is sport mode and some burble when shifting. Open her up though and Ollie can get a bit anti-social.
Brake lines need to be upgraded to braided steel and I'm actually of two minds about the VIS hood. It would probably look pretty good once painted but I'm a little worried about fit/finish and security of it. Really don't want something that's going to rattle or make noise. If I could find a hood cheap enough I'd rather apply the left over to a set of Ohlin's now that they make them for the F56, along with a set of Vorshlag camber plates. Never been a huge fan of BC Racing. They get the job done and were all that were available at the time but I've never been pleased with their dampening.
Intake manifold with the direct port injections is ready to go. We'll see how long it takes Aquamist to get me the replacement controller. I still need to do something with the meth tank as well to make more room in the boot. The box looks great I think but if I drop the tank through the floor I can reposition it and get a fair amount of space back.
I am thinking of swain for the manifold, turbo blanket for the hot side of the turbo and perhaps a blanket for the (catted ) down. See if I can keep the heat in the plumbing until it hits the resonator ...
Let us know what you get for the turbo blanket ...
I saw a straight pipe in your photo 3 inch exhaust without a cat should flow well and as you said, be anti social when performing
Which BC Racing Shock ? I have heard that their digressive piston design series is good - but no personal experience, let alone on a front wheel drive mini. Swift Springs are supposed to improve their performance - which seems to be more the mode you would want ( this is not your ave daily driver ! )
Oops. Sorry about that, the photo is a bit misleading as the back box looks a bit like the exhaust tip. I'll work on a better shot. Swain is one of the best coatings but if you have access to an industrial oven you may want to look at Cerakote's V series. It's rated to about 1000C and you can apply it yourself. It's what I did on the turbine housing and exhaust manifold for Vlad.
The BC's are the original design from 2015 so no digressive dampening :(
How good is the Cerakote's V series at keeping heat in ? Anybody do anyt before and after measurements ? I am sure it is great for rust ( or lack there of )
I haven't done any testing myself but with any thin film coating I think the best your going to see is around a 15% reduction in exterior temps. For best performance an enclosed thermal blanket such as this is tough to beat. It's what the heatshield over the exhaust is made of and can reduce radiant heat up to 70%. It's called Heatshield Armour and is the 1/2 thick variant. Adding a conventional wrap over ceramic should make a nice improvement but I wouldn't recommend wrapping unless it was coated. Otherwise the wrap can hold moisture when the engine is cold and accelerate corrosion.
Wanted to get a base dyno on spring pressure so I can compare spool characteristics with the Xona later. No meth with boost controller off, so max boost is 14.1 psi and it's getting no spool assistance whatsoever. Somebody get that dog a bone.
Current ETA on the Xona is sometime between Nov. 27th and Dec. 11th.
It won't be on there long but hey... every sticker is worth an extra 5hp right?
No major updates at the moment. The carbon hood from VIS Racing has been ordered. Since no one had one in inventory, it's being drop shipped from VIS direct. Been going through the wiring on the Aquamist and boost controller. Previous install was well done with braided sleeves but I'm cleaning it up some, removing excess wiring and using the 0-5V out from the AEM gauge for the boost reference into the Aquamist. I case anyone is looking for Aquamist install instructions for the F56 I've attached what is being used for this vehicle. Feel free to ignore the boost controller reference and the failsafe reference on a standard F56.
STP Motorsports. I think its technically in Plantation. Definitely not a boutique shop. Real people doing real work for a living. They only charge $75 for three pulls. So it's not going to break the bank. If you're in the area call and ask for Stephan. Super nice guy.
There's also a couple of Mustang dyno's in the area but they are more expensive. Tuning this on the road primarily with a Plex Knock Monitor V3 but sometimes it's nice to use a EC dyno for timing sweeps or static load testing.
Also time to do a little preventative maintenance. So new plugs... very little difference between performance plugs on the B48/46 platform. I decided to go with these. I figured if the M Division determined these and the Champion variant are good enough for the S58, then they should be good enough for Ollie.
Also new injectors and MAF sensor since they are original.
Last edited by Tigger2011; Oct 25, 2023 at 08:41 PM.
Reason: Typo
Another minor update while cooling my heels waiting on the Xona. Ollie already had the lower Powerflex engine mount but the engine still shifts quite a bit under load so it's time to do the upper engine and transmission mounts. Upper mounts are almost new so these should help them last longer as well.
Powerflex bushings are installed and I've made some changes to the plumbing from the original build. Decided to hold off on the injectors till the B58TU HPFP and new valve cover arrived. In for a penny, in for a pound as they say. Carbon fiber hood arrived and installed. Fitment on the VIS Racing hood was very good with only minor trimming needed. I've noted that in the pictures below. I planned on driving it for 30 days to let all the solvents in the epoxy gas out before painting it to match but honestly I think it goes pretty well with Thunder Grey. So I may leave it as is.
Had to make a small slot in the hood for the washer lines and drill one hole to attach the center clip between the nozzles. It was also necessary to slightly enlarge the holes for the nozzles to fit. Honestly though I'd rather have to take some off than for the holes be too large. Something else to be aware of is that the CF is thicker where the headlight trims rings would normally clip in place. So it is not possible to use the factory clips to hold them. Mine are bonded in place with the same polysulfide adhesive I used for Vlad's fender flares.
Was going to take some pics in a different location at the park but Mr. Squirrel kept trying to photobomb the shots lol. I figured if he was trying that hard I might as well share.
The Xona turbo has arrived so next up will be removing the Garrett sticker and swapping turbos. Probably a good thing though as the sticker has attracted a bit more attention than I thought it would.
Yep,all the vents and scoop are functional with the exception of the aft two as they are not open. One of the reasons I choose the VIS though is that there are catch trays under the vents. So any rain that enters the vents is channeled forward away from the electronics.
Thanks Yoshimura! It's different for sure. I'm finally getting around to pulling the Garrett GT2871 and installing the Xona 4951S. Xona has a smaller compressor 50x68 vs 53x71 but the turbine wheel is larger 57x51 with staggered blade height vs 54x47. Obviously newer tech with ceramic bearings, new pre-load system, dual shaft seals, billet stainless housing, billet comp wheel, etc. I already replaced the Tial BOV with a Turbosmart and am replacing the Tail wastegate with Turbosmart as well. The hope is the new turbo will give better spool with less back pressure. I'll dyno it again on spring pressure for comparison before I re-tune it.
Small update. Loving the Xona Rotor so far. Spools quicker, sounds great and no more surging. Haven't had time to do much else with it other than cosmetic stuff. Next month I'll be trading in my house with a one car garage for a three car. Can we say lift? Please and thank you. So hopefully I'll be able to get both of my projects back on track. On the cosmetic side, I found out after the fact that the VIS Racing hood is not clear coated when you buy it. With a one car garage Ollie spent most of his time outside and water spot stains were a PITA with bare epoxy. I considered clearing the whole thing but was previously leaning toward matching paint. Bought the adhesion promoter, primer, paint and clear, then did the initial prep work and wet sand up to 600 grit myself. I haven't painted cars in many years but luckily... I know a guy... that owed me a favor. Ended up splitting the difference and matching the hood but clear coating the scoop. Think it turned out pretty good but still need to make some adjustments.
. New engine has 10.2:1 Supertech pistons, H-Beam rods and Supertech valve springs and titanium retainers. Other than springs and retainer the head is stock and everything is held together with ARP studs. Here's the first built motor coming out.
3 inch exhaust without a cat should flow well and as you said, be anti social when performing 
Ended up splitting the difference and matching the hood but clear coating the scoop. Think it turned out pretty good but still need to make some adjustments.
