Effect of 2010 LGT header vs "regular" header/UP on turbo

[ClimberDHexMods]

I bought a Yaris today.

 

exactly what you might expect to hear from a guy also reworking a perfectly good exhaust setup and rerunning it because he can.

[lookslikeanevo]

[mwiener2]

exactly what you might expect to hear from a guy also reworking a perfectly good exhaust setup and rerunning it because he can.

 

I got the Yaris so the OB could sit. Sitting is good. Things turn out better when they sit. Don't sleep, just sit.

[Full-Race Geoff]

Hi guys, my apologies for the delay in coming on here and responding. This topic is very dear to my heart, and I wanted to make sure my first LGT.com post was an appropriate thoughtful response - informative + educational. We've been working on the low mount twinscroll EJ project on and off over the last few months and made some prototypes, none of which pleased me. We finally have a design solution that meets our criteria, and are working to unveil it at SEMA this november.

 

First of all, what I recommend everyone do is think about these turbo systems as "SYSTEMS" - not just a compilation of parts. The overall performance of the entire system as a whole is what matters, and "area under the curve" in the most used portion of the RPM range is what ultimately makes the car "Fun to drive" - isnt fun the reason why we're here?? Also, dont forget whenever looking at dyno charts, a dyno is only a steady state test that does not show transient throttle/boost response -- two of the most critical aspects of proper twinscroll turbocharging! What makes a car fun to drive is NOT how much power/tq the dyno spits out. I personally prefer a responsive 450whp twinscroll setup to a 600whp singlescroll setup -- all day, every day.

 

Secondly, TS is much more than just theory; its been around for 30 years and im honestly amazed that some well regarded "tuners" have such a hard time embracing this. The gains on a 4 cyl are well known, well documented and now almost universally adopted for any modern OE-turbocharged vehicle (petrol or diesel). The posts made by 'Boostin' on here are downright exceptional and some of the best twinscroll postings ive ever read -- huge thumbup to you Boostin!!! If anyone else would like me to go into further detail about any of the points or SAE journals that Boostin posted up, i would be happy to do so.

 

Lastly - Full-Race turbo kits are designed to be versatile and easy to use ANY TURBO from any mfg- whether its singlescroll, twinscroll or some of the new modern turbos that have yet to be released. However. the improvements that can be had with a fully sorted twinscroll turbocharger (designed properly) are reason enough to never use singlescroll again, except in applications where the twinscroll cyl pairing is not possible.

 

 

Now to the postings:

 

The chief advantage performance-wise of the 2010 LGT comes from the use of a twin scroll header. Twin scroll headers separate the exhaust pulses according to the firing order, so that (in the case of a 4 cylinder boxer) each bank's exhaust pulses never interfere with each other. Because they never interfere with each other there is less back pressure for the engine to work against: Firing order is 1-3-2-4. The 1 and the 2 are connected to one scroll while the 3 and the 4 are connected to the other. The pulses never interfere. Each scroll is pulsed in an alternating fashion.

Locating the turbo closer to the exhaust ports reduces cat lightoff times. This emissions control strategy (moving the cat closer) is being used universally across manufacturers of 4 cylinder engines.

 

^^^ exactly right. also, because the twinscroll manifold is divided in half, the internal volume is also halved resulting in higher peak backpressure with a twinscroll, while a singlescroll will have higher average backpressure

 

I'm looking at a Borg Warner S200SX with T4 divided flange. I've researched it decently and understand it alright, and it appears to be the ideal turbo for my goals over what else I've seen. I do not have a built block, so this turbo allows me to get some good purchase at lower boost levels. Also my trans is a 5eat, and that was a huge part of my turbo decision.

 

Great choice in turbocharger. BorgWarner recently released an updated S200SX 75-70 which replaces the older version on our website. This new 75-70 has the exact same compressor/turbine wheels and the same turbine side. The difference comes from the new 4" inlet ported shroud compressor housing and Vband attachment to the center section (no more stinkin bolts!!). This makes installation and maintenance a breeze since there is only 1 nut and the comp housing comes off. no fiddling with bolts, straps, etc. Previously the 75/70 was only available with the small (approx 6" OD) non-recirculated compressor cover. The recirculated cover AKA ported shroud for this turbo is larger (~7" OD). The vband compressor housing is a wonderful update and they way they machine precise countersunk steps its impossible to leak like the GT30R/35R which often leak between comp hsg and backing plate. With this new comp housing i believe this turbo will be a heavy hitter for the smaller twinscroll turbos

 

http://full-race.com/prototype/twinscroll/S200P/S200P.jpg

 

http://www.full-race.com/prototype/twinscroll/S200P/S200P-2.jpg

 

it comes standard with the 1.22, but another hsg is only $150 and i believe it would be worthwhile to test 1.22, 1.15 and 1.09 a/r

 

 

I would have my compressor side on driver side, and hot side on passenger side. Turbine outlet would follow the path of the UP location, over the frame rail/axle/tie rod, and follow the old DP path. 3" all the way. Perhaps 3.5", not sure, don't know much about sizing exhausts. But that's easy stuff to do either way, point is I only see that one way to easily run the exhaust post-turbo. Air filter and compressor inlet can really be run anywhere. driver side is fine. Lastly, I would flip the intake manifold. FMIC hot side on driver side, cold side on passenger side. All short runs this way. Make sense? Going to ask him to weigh in on this, since he would know better than most.

 

youre on the right track so far! good work

 

FR has a very nice TS manifold. But I have yet to see it perform notably well on smaller set-ups.

 

ouch! I know you like the smaller turbos, and while we almost never experiment with anything under 500whp, this twinscroll S300SX 83-75 STI 2.7L engine qualifies as "notably well" around here:

 

http://full-race.com/prototype/researchdocs/jordanmartins83-75-FRtwinscrollkit.JPG

 

200tq by 2800rpm

300tq by 3400rpm

400tq by 3700rpm

500tq by 4300rpm

 

i cant get my RB26 do this, and 2JZs *might* touch this, with a stroker motor. Putting that in perspective -- i dont know any engine that can spool as well as the EJ25 with our twinscroll kit. Evos come close, but the EJ engines have really impressed me. With a stroker they are downright amazing.

 

On a 40R turbo recently on NASIOC it spools up fantastic for a 40R. (spool at around 4000 rpm) I believe this is because the extra VOLUME required in our set-ups. That nice pulsing Is reduced the farther away from the cylinder head we position the turbo. Now of course the pulsing affect is amplified by the higher rpms a 40R turbo spools at. But it doesn't seem to work exceptionally great (I didn't say bad) at 3000 rpms where we would like the smaller TS turbos to spool.

 

i dont follow your logic on this - Are you suggesting that much of the pulse energy is lost becuase of the runner length? If so, I respectfully disagree. In fact, the twinscroll systems tend to work better and better with smaller turbos - hence the reason the OEs all go this route. Again - you might not see this on a dyno, but it can clearly be felt at the gas pedal. We are actually working on a project right now for a major OE who's requirements are such that it is not possible to reach their goals any other way besides twinscroll petrol direct injection with a smallish twinscroll turbo. If you are suggesting that a singlescroll could work equally well at those low rpm points, that does not make sense becuase the volume of the header grows so substantially.

 

You are correct that the larger volume will require more shaft speeds before the boost threshold is crossed ie: the same reason that larger diameter and longer charge piping only serve to add more lag. for the reason of reduced volume AND low CG as well as ease of production, I am a fan of this design.

 

IIRC I was the first to talk to Geoff at FR about this well over a year ago. but if I where him I wouldn't make anything for the LGT unless he knows the new Impreza platform will be the same, wouldn't make any money off of it!

 

yes ben you were the first to suggest this to me. Shortly after that, Tino in AUS started working on his setup and I helped advise him. Now that the low mount twinscroll is working well for him we've received interest for a low mount twinscroll kit ala 2010 LGT style. We have built a few mockups of this style header, however none of those designs would make it into production for a variety of reasons. We recently purchased a 2010 lgt oil pan and pickup and will continue to work on this design. There are some very exciting turbocharging developments due out this fall, and some of that technology makes a setup like this possible. I can not give away the Colonel's secret recipe yet, but I can tell you that the world of turbocharging is going through massive changes right now - and all aftermarket turbo enthusiasts are going to benefit BIG from this.

 

 

this would be ideal for a FMIC application, just literally pipe the inlet up the radiator in to the engine bay to where teh stock filter currently is, and for the outlet, just across the back of the radiator, U bend to the front of the radiator, into the FMIC core, and then the outlet side of the FMIC is just like all the current kits. Exhaust is cake

 

agreed, the shorter charge piping length from turbo -> IC is a tremendous spoolup benefit. definitely one of the best aspects of this entire setup

 

 

The scavenge pump is off the timing belt supposedly, so I'd rather not even try that when I can hook up an electric (unless someone tells me it's easy and cheaper, which it probably isn't). Brackets are different I think. Oil pan would be nice to use but there's a brace in the way I think. Then with E85 my 850s will run dry with the S200 I want to use (goodbye another $400 for switching cost). The turbo sump might work, but probably isn't necessary as STS doesn't use them and everyone is happy.

 

i also hope the timing belt mounted scavenge pump can swap over, but i really have no clue. I would not suggest the turbo sump, they rarely work in my experience, the only legit way is to run a scavenge pump. these guys make the best one out there currently: http://www.rbracing-rsr.com/oilsystems.htm

 

for injectors ID1000cc are the best ive ever used, they work great on E85, especially when paired with bosch 044. be sure that your fuel pump(s) have their own dedicated relay also!!

 

Does anyone know of a easy and cheap way to bolt a mechanical belt-driven oil pump in line with one of the accessory belts? My guess is no, but wanted to check. I don't want to replace the A/C compressor like the Cosworth dry sump pump does (it gets hot in Texas ), but something along those lines of a pump retrofit would be appealing. It would have to be a pretty sturdy bracket to mount a pump properly, so my guess is it's not realistic to mess with that kind of metal work unless someone already knows that it can be done pretty easy.

 

i hope you find a solution, but electric scavenge is probably going to be in your future..

 

 

i hope this gives you guys some food for thought. ill do my best to stay up with the discussion!

 

-geoff

[LittleBlueGT]

First of all, I am extremely glad you are on this forum now. Never take anything I write personal, I just say what I see. I REALLY REALLY want a TS application that works for my needs, I have searched high and low for one. I have solicited logs from people in Asia, the UK and Europe, trying to find a TS set-up for our 2.5 liter motors that works for what I want, and I haven't found it yet.

 

I had a couple of theories on the issue, I will discuss further down below:

 

ouch! I know you like the smaller turbos, and while we almost never experiment with anything under 500whp, this twinscroll S300SX 83-75 STI 2.7L engine qualifies as "notably well" around here:

 

http://full-race.com/prototype/researchdocs/jordanmartins83-75-FRtwinscrollkit.JPG

 

Trust me I saw this set-up on NASIOC, and it is very good. It does not fit MY definition of a smaller turbo. I want 300 wtq at 3200 rpm, not 3400 rpm on a 2.7, which would be 3800 rpm on a 2.5. FWIW there are turbos that have done this:

 

The best I have seen is the SS 3076, not even a new billet fancy wheel (I know Billet is just for quicker manufacturing). I know in theory a TS should be able to do better then this, but so far I have yet to see one have this kind of spool and 400 whp. (this is a lower reading dyno then P&Ls FWIW)

 

http://www.efilogics.com/dyno/graph.php?gb=0&hp=1&torque=1&rpm=1&sl=1&sln=1&runid1=662&rgb1=000000255

 

 

 

i dont follow your logic on this - Are you suggesting that much of the pulse energy is lost becuase of the runner length? If so, I respectfully disagree. In fact, the twinscroll systems tend to work better and better with smaller turbos - hence the reason the OEs all go this route.

Remember, I was the one that scanned in and sent you the articles about BMWs dual TS turbos, and dumping the dual SS on the 335 and going with one TS unit.

 

I just don't see it happening on the ABSOLUTELY MASSIVE pre-turbo exhaust systems we have on our cars. I see TS 35Rs and bigger turbos working very very well, spooling better then any SS ones, but I just don't see it happening on the 55lb/min and under turbos (preferably less then 50). My theory, and perhaps I should elaborate, can be described this way:

 

-small 47 lb/min turbo, it wants to spool at 3200 rpm on a TS on our 2.5L, but so much exhaust energy is wasted in the long runners, that it spools at 3800 rpm. (I am not saying it is worse then SS, just saying it doesn't appear to be better)

-now take a 60 lb/min turbo TS, it wants to spool at 4200 rpm, but because of the same problem with the smaller turbo it spools at 4500 rpm.

 

Why only 300 rpm later on the bigger turbo, and 600 on the smaller one? Because there is now a lot more heat energy going through the system at the higher boost threshold, thus partially negating the handicap of the ABSOLUTELY MASSIVE pre-turbo exhaust plumbing.

 

Just a theory, I would love it to be wrong, please please prove it wrong, with a 50 lb turbo TS on one of our cars that spools hard at just over 3000 rpm!!!!

 

yes ben you were the first to suggest this to me. Shortly after that, Tino in AUS started working on his setup and I helped advise him. Now that the low mount twinscroll is working well for him we've received interest for a low mount twinscroll kit ala 2010 LGT style. We have built a few mockups of this style header, however none of those designs would make it into production for a variety of reasons. We recently purchased a 2010 lgt oil pan and pickup and will continue to work on this design. There are some very exciting turbocharging developments due out this fall, and some of that technology makes a setup like this possible. I can not give away the Colonel's secret recipe yet, but I can tell you that the world of turbocharging is going through massive changes right now - and all aftermarket turbo enthusiasts are going to benefit BIG from this.

I kinda think this style of turbo will make its way to the Impreze chassis. I think it has to for Subaru to compete with others in the hp department, and emissions.

 

If you guys are first to the party (vs almost last) maybe you can get a good hold on the market when one does come out in a non-LGT platform in 2013 or so.

 

We can always hope!

 

 

 

At any rate, good luck with the TS project on a normal exhaust manifold that places the turbo where it should be (close to the cylinder head, not under the car:lol:). I am eager to see how it works, and as always, send me the logs!!!!!

 

 

 

ps:

 

Also, dont forget whenever looking at dyno charts, a dyno is only a steady state test that does not show transient throttle/boost response

I agree, but if something is happening, it can be described, it can be logged, it can be conveyed. A dyno chart may not do it, but take a look at this thread I made some time ago about road-logs in lower gears to see response:

 

REAL turbo data ....... by LBGT!

 

 

Ben

[torinalth]

i also hope the timing belt mounted scavenge pump can swap over, but i really have no clue. I would not suggest the turbo sump, they rarely work in my experience, the only legit way is to run a scavenge pump. these guys make the best one out there currently: http://www.rbracing-rsr.com/oilsystems.htm

 

 

I read through that page, and do have one question that it ignores (and maybe ignores because it does not need to be talked about). The 2010 legacy has a oil pan for the turbo its self. The page seems to state that you just need the pump and nothing else coming off the turbo. is this correct?

 

if that is the case, then essentially the entire system revolves around lengthening the oil and water feel lines to reach the now lower mounted turbo. placing the new electric scavenge pump after the turbo, and then wiring the pump to a switched fused source. pump takes care of the oil, convection takes care of the water, and them all you really NEED is just the piping for the header and exhaust connection, intake and FMIC connection.. then maybe a new under tray to protect it..... very interesting...

 

T

[Full-Race Geoff]

ben -- i guarantee you the turbo technology thats just around the corner is going to blow your mind. sorry to be a tease and not give up the nitty/gritty details, but this is such a monumental development for the turbocharging community that its the first "game changing" development Ive witnessed in our industry.

 

torinalth -- what you are saying is correct: with the electric pump, you will not need a seperate mini oil pan for the turbo. Also there are some technological advancements coming soon which allow this type of system to be far more practical.. sorry to be so vague

[ClimberDHexMods]

So basically I have to wait until November to avoid investing in what could become antiquated technology...

 

Is it variable geometry or electric assist? At least we know one thing... it will be twinscroll.

[Full-Race Geoff]

you dont HAVE to do anything. im just letting you know whats coming

 

btw twinscroll does not match with variable geometry -- its one or the other... but not both

[ClimberDHexMods]

you dont HAVE to do anything. im just letting you know whats coming

 

btw twinscroll does not match with variable geometry -- its one or the other... but not both

 

Allow me to take a stab at this one: Variable twinscroll. One actuator and two separate vanes. Physically possible though it's anyone's guess where it would be beneficial to have that much extra size and weight. Maybe farm equipment or tanks of the future

 

But back to topic, is there ANYTHING more you can tell us? (You can tell I'm from the generation of instant gratification )

 

And would you like an extra (free) hand setting up / closing down your booth at SEMA?

[Full-Race Geoff]

This is what i can tell you --

 

-its not variable twinscroll

-it is a result of thinking wayyy outside the box, and still retaining compatibility with many existing turbokits

-no weird gizmos, magnets, spool valves or electric motors here

 

i know that doesnt answer your questions, sorry edit:i may have said too much already

[LittleBlueGT]

This is what i can tell you --

 

-its not variable twinscroll

-it is a result of thinking wayyy outside the box, and still retaining compatibility with many existing turbokits

-no weird gizmos, magnets, spool valves or electric motors here

 

i know that doesnt answer your questions, sorry edit:i may have said too much already

 

Anyone catch the pre-edit?

 

pm me

[ClimberDHexMods]

Anyone catch the pre-edit?

 

pm me

 

ditto, PM me too please

[ClimberDHexMods]

This is what i can tell you --

 

-its not variable twinscroll

-it is a result of thinking wayyy outside the box, and still retaining compatibility with many existing turbokits

-no weird gizmos, magnets, spool valves or electric motors here

 

i know that doesnt answer your questions, sorry edit:i may have said too much already

 

Well I believe in you and your company, and I will wait until you reveal it Unless I find out before hand (in which case I WILL NOT go public and ruin the surprise for you

 

 

 

On a different note (per this thread), I don't think the 2010 LGT oil pan is going to bolt up to a 2009 and under car. Engine yes, but that cross member or whatever it's called is in the way as far as I can tell from pictures. I was looking at it last night on my car.

 

See the 2009 and before versions: http://forums.nasioc.com/forums/showpost.php?p=27383408&postcount=36

 

Now compare it to the 2010 LGT pictures, as well as the PDF Underdog (FBP) posted in this thread. The cross member sits like 5 inches back on the new car.

 

The 2010 oil pan appears (from limited pictures) to drop straight down from the flange in the back, not angle towards the front of the car like pans of previous years.

 

If someone at a dealership can just lift up a 2010 and zip off the plastic cover and confirm, that would be awesome! Otherwise it's cut and weld in the future (if Full Race doesn't change things too much ).

[Full-Race Geoff]

2010 LGT oil pan arrived this afternoon. ill let you know how it fits on my GD clip... hopefully will have some time tomorrow

[mwiener2]

I got the oil pan yesterday. Will NOT fit. It doesn't work with the crossmember. Looks like it's time to fab an oil pan.

[ClimberDHexMods]

I got the oil pan yesterday. Will NOT fit. It doesn't work with the crossmember. Looks like it's time to fab an oil pan.

 

Was thinking about how best to do it, and got the idea that one could create a V around the pickup tube. Let's see if I can draw it with characters with headers too.

 

Back of Car

____

=V=

..@ Turbo

 

Front of car

 

So I'm thinking if there is a V shape part of the pan just in the front of the oil pickup tube, the stock pickup can still fit, and the headers can kind of follow the contour into the turbo as they bend forward from the = shown, down to the turbo (@).

 

I hope that makes some kind of sense.

[Full-Race Geoff]

yeppers, its a no go - keep us posted with what you come up with mwiener2! if you build a solid pan that would be great

[mwiener2]

Bought a sheet of stainless today and the oil is draining at the moment......

[mwiener2]

Somebody just bought a 500hp capable turbo today...

[LittleBlueGT]

You gotta show us some pics.

[mwiener2]

I have pics of a 2010 leggacy oil pan, under engine thingy that connects to pan, and a 2010 oil pickup tube. The other pics are of the dissasembly of the bottom front of the car. Anything you wanna see there? (no pics of 2010 assembly held up to 2005 engine, too heavy to hold and take picture at same time)

[ClimberDHexMods]

Somebody just bought a 500hp capable turbo today...

 

Which one?

[ClimberDHexMods]

Questions for Geoff or anyone else who can answer based on real experience or research of real experience:

 

What is the optimal diameter exhaust post turbo for a 44lb and 55lb turbo, respectively?

3", 4" for example? I know optimal is virtuall no exhaust or vacuum, but wondering practically what diameters lower post turbine pressure pretty well before the return diminishes and you start getting a lot more noise than anything?

 

Second, have you experienced a length of pre-EWG tee runner length where boost control starts to be impacted? For example, 1 foot of straight pipe, 8", 6", etc?

 

Thank you in advance for help with these somewhat ambiguous--but relevant to thread--questions.

[mwiener2]

Which one?

 

It's a twinscroll variable physics 45-80lb/min monster