This type of compressor surge happens mainly in high gears (5th or 6th on the freeway) when you floor it and create lots of load at low RPM. When surge occures in this situation, it only happens for a short period of time an then goes away. The sound of this type of surge is kind of a fluttery sound, but very very fast, and short.

You don't see this on hondas (because drivers never keep the revs low), or on Supras because their engine is much larger and consumes more air. This is very common in the EVO/Eclipse/WRX world, where there are guys making OEM fittment, large turbos.

Lots of cars have this problem with turbos that use small turbine wheels and or small AR turbine housings and big compressor wheels. This causes the turbo to spool very quickly (a good thing). If the Turbo starts to flow more than the engine consumes then surge happens. But then goes away once the engine air flow catches up. Also only at pretty high boost levels, rarely does it happen below 20PSI on cars.

Compressor maps for turbos all have a surge line indicated on them for this reason. This is the line to the left of the compressor map.

This is the turbo we use, and you see that IF the turbo could spool up at 2000RPM it will have some compressor surge. But because the engine would be reving pretty fast out of that area, it most likely isn't something noticable. But the GT2560 turbo is a great match for the engine, and it flow possibilities.



This is not a turbo that most likely will never see the light of day on the Mini, but is shows an extreme example of compressor surge. This would really show its head on a drag car using NOS to get the turbo spooling.

In the end this type of surge is not very common and this is probably more info than most want to know. But in the end if turbos continue to be what comes on the Mini S.........................

Who knows for sure! The r56 has one really good thing (but can be bad) going for it. It has a MAF sensor! This is good because it tells the ECU exactly how much air is being consumed by the engine. Along with ambient temp, and manifold temp, the ECU can calculate fuel, and timing. What we don't know is when the ECU will freak out when it sees too much air flow. It may not but you never know.

With in reason, running the same boost curve (the 14psi-ish we have seen) the turbo will be much much more effiecient and in turn make more power. And of course be more efficent at higher boost levels(when we can falsh the ECU). The stock turbo only flows so much air, which means that it may not hold more than 12psi at redline. and this is something we started to see with our inital testing with our ALTA wastegate and boost controller.

 

Something that has been making me question the R56 is the direct injection and it seeming to be the limiting factor in modding the car. Have you all come up with any way to get around that and get more fuel to the motor for more mods? I am not super familiar with turbos, so I am not sure if the DI will effect the performance of a larger turbo or not. Thanks!

 

Ahhh, but DI is a good thing for many reasons! Cars can run leaner, safer, and in turn more power. Also more timing can be added (more power again). Also DI and its nature of really high pressure allows for more head room as far as fuel delivery goes. But this is not something ANYONE should worry about for a long time. Or until we can start tuning and flashing cars with big big turbos.

I love DI and i think it opens up a ton of head room on these cars!

 

Also the above graphs are of engine air flow plotted against different turbo compressor maps. I didn't really make it that clear sorry!

 

Cool! I was concerned that there would be an issue getting enough fuel to handle the mods such as the turbos you all are going to offer. It's good to see the new MINI is going to be capable of this much power!

 

mmm compressor graphs [me like]!

 

I think that there is a problem... I've noticed that european engines haven't got the MAF sensor. And...they have got different air filters too.
Please check and confirm,but I'm quite sure.

 

That would be good, and bad! You might be looking at the non-S???? Hmmmm, stranger things have happened.

 

I can ensure you that the european mini doesnt have a maf(because mine doesnt have) and you can see that here!

 

Intake systems are different. But I'm not sure EU spec cars don't have MAF sensor. It may be located somewhere else. But from the pics below you can see there is no MAF sensor on EU spec cars. Also filter elements don't have the same part number.

 

so if i could make 20psi plus at 2000 rpm on an antilag system... i might get compressor surge? Seems like all nam-ers are going to experiance this... Also, cams are going to affect this as well...

Gt2560? it is a great all around match... however... I will be looking for the first guy willing to put a 35R or 4088 on his car and change the way the world looks at MINIs.

 

WELL THAT SUCKS! Looks like we will have to make something special for the Euros! That also means that most of the ECU flashes being made over there, will not work on the US cars!

Yes, those turbos are the big boys that most likely will not see the light of day on the Mini. At least for a while! We have or i should say HAD pics with a GT4088 in the engine bay, as well as a 3582R. (I say had, as we had a HD failure, and they are lost) Both for fun, but there is just no way that will happen anytime soon. They just don't fit.

The GT2560R, and GT2860RS are the best matches for the engine, and in a month or so we will be dynoing them once some other testing is done on the car with the stock turbo.

 

well the 4088 and the 35r fit... you just have to know where to put it

 

Any news from ALTA yet??

 

Put me down for a kit after you get the reflash and stuff sorted. Car needs a little more oomph. I'm definitely in on this one!
Also please use the stock dv it works AWESOME when its electronically activated. Part throttle is awesome on this car.

 

No dice there, or at least don't bet on it. The stock electronically actuated diverter valve is built into the K03's compressor housing. Someone [like ATP] would have to go on a limb and cast a custom compressor housing just for our application to impliment the stock diverter valve. It's mucho easier to get a quality pneumatic/spring diverter valve and impliment that into the charge piping back to the compressor inlet. It's possible to have it tuned so it provides excellent drivability with no leaking, you just have to know how to do it.

Cheers,
Ryan

 

I suppose... my k03 apr car surges pretty badly part throttle. Its not bad you just have to work wtih it. The electronic dv works awesome though, and its easy to mill a piece for it to work even if its atmospheric, its a little tube that the rubber diaphragm slides into. Shouldn't be too hard.
Yeah I guess on a bigger turbo no problems, k03 is peaky and crappy.

PLEASE ALTA HURRY LOL

 

Surge will not be a problem..... That is an easy fix, and something you will not have to put up with. This is not an issue with the turbo, but your BOV.

Using the stock BOV is ok, but kind of limiting. We have something up our sleeve here also! Just wait!

a96bimmerm3,
ECU stuff is a long ways away. I wish it was closer, but i think the end of the year is realistic. I know, that is not what you want hear, but........ Dare i say Hydra............. This might be a quicker to get to market.

 

Here is an update!
Catbacks are finally shipping! Just had been waiting on the clamps!

 

Thanks Jeff. By the way, nice talking to you yesterday! It was really informative and great. Alta definitely has my continued business. Customer service is awesome, you guys rule!

Regards,
Josh

 

No problem! Thats why we are here!

 

I assume this is the Catback exhaust systems for the R56? When will this be available to order from your site and any sound tones clips? Oh yeah how much?

 

The kits are $729.99, available now! Sounds clips are coming soon!

Thanks again!

 

great to hear.

by the way, on your website under the "CHARTS" tab, the dyno chart does not show. there is only text.

 

CRAP! I will get someone on that in the morning. Thanks for the heads up!