scorke

iTrader: (18)

You are picking the exhaust housing based on the VE of the motor and what you want out of it, building a car/engine/turbosetup based solely off of a desired exhaust housing is not the best way to achieve whatever your goals might be (IMHO)

Scorke

ITS n STI

where did you get off thinking that's what I was saying?

Ron Shearer gets it.

ceegutta

Well I'm not using a Garrett hsing. I'll be using a Holset TS housing which has an AR of about .90+ or 1.00+ and also is a T3 hsing. So based on the later part of your statement ,I'm taking it that a T3 TS mani is good on a 2.0L motor if the right sized or a big AR sized hsing is used. If one owns a Garrett turbo with a T/S housing it would be better to go T4.

I guess the way it was stated in your first response where you mentioned that a T3 TS mani sucks seemed pretty general to me. Glad you sort of clarified it though.


On a 2.0L motor,
If one goes Garrett and TS, use a T4 mani
If one goes Borg Warner or Holset TS, T3 or T4 mani is good because of the larger sized A/R turbine hsing options that could be used.

scorke

iTrader: (18)

I tried!

I think its just a matter of going with smaller individual routes for the gasses going to the turbo (when the housing is not big enough to take advantage of the DIRECT benefits of twin scroll) the benefits will be marginal, possibly worse because of the misatch.

I don't think the 1.0 T3 wil lbe big enough on the other turbos either but I am not sure how mcuh bigger the compressor is on those, on the borg I assume a much bigger compressor cover at least, not familiar with holsets.

I bet a big housing 30R on built fit would be a nasty DD

Scorke

Shearer

iTrader: (6)

Ignorance is bliss Geoff. I can say that I'm not pulling engineering cues from the latest monthly issue of a marketing magazine. I'm always looking to learn something new and my education is always ongoing. I'd love for you to educate me on something however. Give me proof that what you are pushing so heavily works. Solid proof and not some crap you read in an engineering handbook or a quote you ripped off from BW. Give me something. All I have seen from you is a bunch of steam vapor to propel your latest marketing engine and cash cow.

Show me some data. I'd assume the self proclaimed manifold engineer guru would have shelves of three ringed binders filled with some conclusive data. Many people from different venues have asked for you to back up your mouth, several have offered resources, your own dealers have called you out on your "outlandish claims", and yet you have never come through with something conclusive. So please give me an education or are your real world engineering skills still a little too wet behind the ears?

Really? Just to make sure I wasn't talking out of my **** I contacted a buddy who is an App. Engineer for Honeywell. He confirmed with me that the divider is not taken into consideration when determining the A/R.

And to satisfy some curiosity. Weren't you an ex-employee of Honeywell? My apologies for any spelling mistakes as my memory is rusty. Last name Kavanaugh?

You are correct in saying that. I also do not dictate what turbine housings the manufacturers include with there turbochargers. My t4 manifold line-up is dictated by the turbo manufacturers and my desire not to have a plethora of part numbers for divided and un-divided manifolds. There is no draw back to using a divided manifold on an undivided housing.

Ted B

iTrader: (6)

Whoa, this statement is glaringly incorrect. The greater the magnitude of change from the exhaust primary into the turbine housing, the greater the loss in pulse energy.


My 2.0L engine with HTA 3582R TS T4 outspools "ITS n STI's" quoted Subi example by some 300rpm, despite the fact that it is down on displacement by a whopping 20%, and the Subi uses only a turbo of only <10% greater compressor capacity. The quoted Subi setup is empirically inferior on all counts.

My 2.0L, despite being 'handicapped' with large primary diameter exh manifold, longer rod ratio, DI intake, and 3" UICP (all proven to increase spool time), outspools a well known, competently tuned 2.0L of comparable build and HTA 3586R (supposedly <100 rpm difference in spool) by a rather huge 800-900rpm. And yet, the TS T4 housing I am using is proven capable of reaching power levels beyond the practical limit (~750whp) of my turbo, which negates any argument of the housing being 'small'. I'm happy to capture this comparison on video if you like. The difference is rather obvious.

Furthermore, I'm more than willing to allow a few regional large turbo EVO owners have a turn at the wheel of my car so than can describe in detail the disparity in response, just as I observed when I made the switch. The difference is apparent as soon as one pulls away from a stop in 1st gear.

I have nothing to sell, and I am sponsored by no one. I just report it like it is, and I clearly see why OEMs have migrated from open housings to twinscroll and not the other way around.

vboy425

iTrader: (19)

ouchh

ITS n STI

Please don't compare a 4g63 to an ej25, let's keep this discussion apples to apples.

evoPirate

iTrader: (12)

Good point, and exactly what I wanted to say after reading the very first thread. Pointless thread, sorry, but you're comparing 2 completely different engines and the results will never be similar. I do wish some people would get that (no personal insults here...just see a trend of suby/evo guys comparing apples to watermelons). Just like when my Suby buddies say a Red or Green is the wrong turbo for my car cause they're so incredibly laggy and don't make good power.....

Shearer

iTrader: (6)

Ted,
You're seriously comparing spool characteristics from two completely different, not even close, engines with different turbos?

a1091156

Shearer, here you go > http://www.sae.org/technical/papers/972775

Its only $15 and well worth it. At least this topic will end once and for all.

Here's another paper, on the rotary Engine though, with their test results on the Twin vs Single entry > http://foxed.ca/RX-7/SAE%20papers/New-tech90-1-6.pdf

QED

scorke

iTrader: (18)

Ted you meant to say Increase spool time not decrease spool time whilst listong those mods i believe

Scorke

juanmedina

iTrader: (1)

I like this thread

Ted B

iTrader: (6)

I seriously compare different engines of similar displacement with similar turbos all the time. I'm sorry if you found this confusing. If this EJ25 cannot withstand more power than ~18psi generates, and that doesn't come until 4300rpm, that already represents lazy spool characteristics and limited power capability for an engine of 2.5L displacement. The purpose of the comparison is to illustrate why improving transient response should be the top priority for the EJ.

The second example is between two similarly 2.0L EVOs, and considers this observation:

It's about 800-900rpm difference in my case.

Now you two can choose to believe whatever it is that makes you feel better at night, but so far, I cannot recall even one instance in this forum whereby a TS user reported anything different than my own first hand observations with TS conversion. Not only does TS work, but it really works. The physics behind why this is the case are not difficult to grasp, and I am all-too-pleased to explain and provide analogies if necessary.


Fixed.

ITS n STI

No one is saying a single scroll setup will come on faster than a TS setup with the same A/R.. There are just different reasons for it. You believe it's because of the split pulses and some believe it's because the divided tang cuts down volume and causes the turbo to come up faster.