Truth about turbo positioning

[Decay107]

Originally Posted by johan

That pre-cat should be labeled "fuck show".

Look on the bright side, at least it wasn't a permanent part of the manifold. Can you imagine if a manufacturer did something as stupid as that?

[mitch t]

Originally Posted by johan

Aftermarket availability is irrelevant... OEMs are way too smart to waste their time/energy on that. A turbo post catalytic converter is madness.

I an not suggesting that the OEMs would run a post cat turbo, and you are not entirely correct about the "felony to remove the emissions equipment" statement. Here are a few points.

1. All FI kits remove/replace emissions control equipment. ( intakes, air filter boxes, computer tunes, and sensors are all included with the cats under the heading of "emissions equipment ").

2. Removing and replacing these items is perfectly legal if there is a CARB/EPA certification-exemption for your specific application. This is an expensive, and difficult process,(I had to deal with it while working in R&D at AEM as well as DC Sports, among others) but the OEM guys are super good at it.

3. A turbo kit with the engine>turbo>cats sequence could be made CARB legal if you are willing to go through all that. (Certification of the new cat arrangement)

4. While I am running a SC and I am super happy with it, I am not anti-turbo. I think if I was into time attack, or drag racing, or was looking to make 400+ Hp, I would likely be running a turbo, and I would be just as happy.

Again, not looking to push one over the other, but depending on your priorities, what works best for me, might not be best for you, and that doesn't make one of us wrong.

[bcj]

This has been the most polite exchange of opinions I've seen on this forum.
Well done!

[Tokay444]

Originally Posted by johan

No, no they don't.

Subaru made that mistake on the 02-05 WRX and then removed it after the cats were failing and destroying turbos. They likely did it specifically so they could bring the WRX to market in the states and didn't do enough R&D to realize it wouldn't last.

So don't delude yourself into thinking it's a good idea. It's not.

I'm not deluding anything. I never stated it was a good idea. I hate all cats, in general.

[_debo]

Originally Posted by johl

Have a look at sydney motorsport engineering on Facebook. Most aussies use their turbo kits. They offer a race and road spec option and can make single and twin scroll manifolds.

There is also a kit made by coyoda. However there isn't much info on Google about this kit

The one from Sydney motorsport is the FA20Club variant which is one of those I was considering because it's sold by few tuners in the UK too. The coyoda one as you said seems premature, there are very little info online and the current impression from the photos is that it's still need polishing, it feels like it's still quite R&D but it definitely look promising.

Thanks for the input.

[_debo]

Originally Posted by Matt@Cosworth

thats a neat looking kit, just the remote wastegate exit that needs sorting so its not exiting under the car and gassing the occupants out in traffic
however a GTx30 is a very large turbo for a 2.0 ltr engine and road use as it won't spool up until 3500rpm or so as I don't think its the twin scroll option

however I have yet to see anyone trying the anti-lag option thats available with these cars.........

What that would be? Then anti-lag option I mean? Also would you be happy to discuss privately few matters? It would be very appreciated.

[Matt@Cosworth]

happy to discuss it openly , in the spirit of moving things forward

on a fair few OEM turbo Gdi engines we have found that they are adopting very late GDi injection timing coupled with a lot of spark retard to create a lot of post combustion in the exhaust and so spool the turbo up quickly
now obviously you can only do this for 20-30 seconds or so before everything gets too hot

but by that point it doesn't matter as the transient / acceleration event has passed and you're back onto steady state
I feel ECUtek is capable of doing this with the custom map function and it would really help spool up a bigger turbo faster than normal
however I've yet to see any tuner try this out

[_debo]

Originally Posted by Matt@Cosworth

happy to discuss it openly , in the spirit of moving things forward

on a fair few OEM turbo Gdi engines we have found that they are adopting very late GDi injection timing coupled with a lot of spark retard to create a lot of post combustion in the exhaust and so spool the turbo up quickly
now obviously you can only do this for 20-30 seconds or so before everything gets too hot

but by that point it doesn't matter as the transient / acceleration event has passed and you're back onto steady state
I feel ECUtek is capable of doing this with the custom map function and it would really help spool up a bigger turbo faster than normal
however I've yet to see any tuner try this out

Thanks for the explaination, appreciated. The reason for the private message was because I wanted to discuss whether or not cosworth would be willing to help me with my project when I am back to UK; I know you are selling a SC kit but I would really like to go turbo with the help of a reputable tuner such as yourself.

As I said previously the kit from Ptuning would be my kit of choice but it's not compatible so I guess the chances are either adapt that kit, go custom or just listen to your professional advice.

[Tokay444]

Originally Posted by Matt@Cosworth

happy to discuss it openly , in the spirit of moving things forward

on a fair few OEM turbo Gdi engines we have found that they are adopting very late GDi injection timing coupled with a lot of spark retard to create a lot of post combustion in the exhaust and so spool the turbo up quickly
now obviously you can only do this for 20-30 seconds or so before everything gets too hot

but by that point it doesn't matter as the transient / acceleration event has passed and you're back onto steady state
I feel ECUtek is capable of doing this with the custom map function and it would really help spool up a bigger turbo faster than normal
however I've yet to see any tuner try this out

I'm coming to this platform from the Mazdaspeed DISI platform, and am extremely appreciative of the caliber of aftermarket companies compared to the Speed platform. I still have my Speed 3, and we've needed support for multiple injection events per cycle for this very reason, for a very long time now.

[mitch t]

Originally Posted by bcj

This has been the most polite exchange of opinions I've seen on this forum.
Well done!

Yea, well, I'd like for folks to click on the links below and buy some skidplates, and I dont think most people like to buy things from someone they don't like.

[VitViper]

Originally Posted by Matt@Cosworth

happy to discuss it openly , in the spirit of moving things forward

on a fair few OEM turbo Gdi engines we have found that they are adopting very late GDi injection timing coupled with a lot of spark retard to create a lot of post combustion in the exhaust and so spool the turbo up quickly
now obviously you can only do this for 20-30 seconds or so before everything gets too hot

but by that point it doesn't matter as the transient / acceleration event has passed and you're back onto steady state
I feel ECUtek is capable of doing this with the custom map function and it would really help spool up a bigger turbo faster than normal
however I've yet to see any tuner try this out

I can do that in my M150 ECU programming. I've dabbled with something like this before, and my concern has been in the 'feel' or drivability of the vehicle -- sure it might start moving the turbo sooner but is it making power to improve acceleration instead of causing what feels like a slight "delay" in the vehicle's acceleration?

Worth experimenting on this motor...

[VitViper]

Originally Posted by VitViper

I can do that in my M150 ECU programming. I've dabbled with something like this before, and my concern has been in the 'feel' or drivability of the vehicle -- sure it might start moving the turbo sooner but is it making power to improve acceleration instead of causing what feels like a slight "delay" in the vehicle's acceleration?

Worth experimenting on this motor...

Well I just spent the last 2 hours tinkering with various code -- with my .82 a/r T3 5862 I can bring the turbo in 700-800 rpm sooner from a low rpm onset (say floor it at 2k or 2500 rpm) but at the cost of power output... to get the that quicker onset the settings you have to use doesn't make the power loss worthwhile.

Transient boost response is identical between shifts whether I'm using injection timing/ignition timing during transient conditions (shifts mostly in this case).

I think a proper boost control system (which the MoTeC has -- I can keep the top of the WG completely closed until the moment of target boost if I want) helps more in turbo spool up than injection timing/ignition timing.

[EAGLE5]

Originally Posted by VitViper

Well I just spent the last 2 hours tinkering with various code -- with my .82 a/r T3 5862 I can bring the turbo in 700-800 rpm sooner from a low rpm onset (say floor it at 2k or 2500 rpm) but at the cost of power output... to get the that quicker onset the settings you have to use doesn't make the power loss worthwhile.

Transient boost response is identical between shifts whether I'm using injection timing/ignition timing during transient conditions (shifts mostly in this case).

I think a proper boost control system (which the MoTeC has -- I can keep the top of the WG completely closed until the moment of target boost if I want) helps more in turbo spool up than injection timing/ignition timing.

Where is the power cost? In that 700-800 rpm or above? Why?

[johan]

Originally Posted by VitViper

Well I just spent the last 2 hours tinkering with various code -- with my .82 a/r T3 5862 I can bring the turbo in 700-800 rpm sooner from a low rpm onset (say floor it at 2k or 2500 rpm) but at the cost of power output... to get the that quicker onset the settings you have to use doesn't make the power loss worthwhile.

Transient boost response is identical between shifts whether I'm using injection timing/ignition timing during transient conditions (shifts mostly in this case).

I think a proper boost control system (which the MoTeC has -- I can keep the top of the WG completely closed until the moment of target boost if I want) helps more in turbo spool up than injection timing/ignition timing.

This is the joke....

The joke is on everyone.

OEMs do this so they can claim their turbo engine has xyz torque from 1800rpm - 6000rpm. Doesn't matter that it destroys transient response.... because numbers win for marketing.