thats a very sweeping statement slorice!
RR's CAN produce similar loads. i agree alot of dyno runs and graphs can be misleading.
but in Si's case the spool was the same on the road
edit: to acknowledge my mistake of engine dyno and chassis dyno

 

Simon Norris and I talk occasionally. He is a very nice guy to deal with.

You cannot however compare his engine dyno numbers, spool up and such with a chassis dyno. There is an engine dyno right across the street from our shop, like less than 200'. I have had engines I own and my brother has had engines he owned on that dyno. The loading on an engine dyno is completely different than what you see on a chassis dyno. My MD could be set up to load the same way but unless you are brake boosting your car, it has no relevance on any real world driving.

I will be using twin scroll, that's what the stock exhaust manifold has

Many of you are also looking at "how well a twin scroll works" but you aren't looking at the entire build, most of the examples you are posting are based on 2.3+ liter engines.

 

http://www.lancerregister.com/showpo...1&postcount=32

From page 3 of that thread. He quotes the spool on the road.

Sorry for the diversion of the thread to the good old TS debate. I think it's probably logical to not argue about it for now and over time we will see what turbo tech becomes the standard for T3/T4 type turbos.

 

Here is a good example of a car we built. This is a 8.5:1 compression 2.3 liter engine, BF272 cams, stock ported intake, 65 mm throttle body. E85 for fuel.

The car had the T67 Ptrim turbo on it with a .63 turbine housing. The T67 is not known for it's spool up. 20 psi at 4629 rpm. The car made 596 whp and 560 ft lbs to the wheels on our dyno. Same car, pump gas and alky, more aggressive tune made 604/564 and hit 20 psi at 4570 rpm.

Same combination, same build, 2 liter though. Same turbo, intake etc. Getting aggressive on the tune, using VP Import, 20 psi hit at 4988 rpm.

Here's another example, V2 intake, .82 turbine housing on a 67-ptrim, pump gas, 20 psi at 5715 rpm, 566 hp, 407 torque.

Twin scroll Full Race header kit, GT4094 turbo, 2.3 liter engine. 20 psi of boost at 4449 rpm. The power was disapointing up top, 492/425 ft lbs. Personally, not impressed on that one.

Anyway, you get the pictures. There is a lot more to making low end than a divided housing, more to it than stroking it too.

 

I only tuned one customer with a BW and as soon as I reached 30 psi of boost it started leaking oil like mad

It was the 3rd time this customer had a bad seal

Al

 

Good point there.

And not to get all mushy but... I love that we have heavyweights in the Evo world like Dave Buschur and Simon Norris. Both of them have helped me on more than one occasion without having bought much from them. Class acts the both of them and I just absolutely love hearing about their exploits.

 

I like your idea - the power FC is great ecu for sure and highly under utilized

 

Great examples

I feel that twin scroll proably is not as effective on a in line 4 as it is on a V6 or V8 engine, This is becuase the runners on a in line 4 are very short.


I have twin scrol now but I doubt I would do it again.

Al

 

Most twin scroll housings were designed for the heavy duty diesel market well before a high strung 4 cylinder was ever even thought of. Computers from a development stand point were extremely rare, if they even existed at the time. Most, if not all, of the divided exhaust housings that come on the turbos I see are borrowed from the diesel line up of turbos that was tooled up years ago.

Yup, As do I when it comes to T4 stuff. I'm not saying twin scroll doesn't work. The fact of the matter is that the majority of the T4 based turbos we use you can only get with divided exhaust housings. Most every divided housing I have seen come through here has been standard issue on some sort of diesel platform for years. From the manufacturers standpoint it is much more economical to incorporate existing inventoried part numbers into a new turbo than to spend the money designing, tooling, and stocking an entire new line up of turbine housings.

I've had some great results with it as well. What I am saying is no one has proven that it works any better than an open volute design. And I am positively saying that it does not work as well as some vendors lead there customers to believe. Not pointing fingers at anyone in particular, especially to whom you probably assume I am. I've had a few people call here and there inquiring about twin scroll. And they've relayed some of the sales pitches they've been thrown how good Twin Scroll is.

I'd love to see some back pressure logs from some of these guys pushing the Twin Scroll stuff so hard.

 

sent a PM to crcain to try not to turn this into a TS debate thread.

 

I have another log here with Shepherd's EVO as well.

2.3L, FP3582 .82 exhaust, big tube T3 Header, yada yada.

20psi by 4574rpm. Car ran 9.9 this way and it is absolutely full weight.

Cheers I'm done with the TS debate in this thread. Sorry to go off topic.

 

So basically the biggest turbo happened to be the only one that was twin scroll, and also happened to be the one taht achieved 20 psi the soonest....

A 40R can make more top end than any of those turbos.

Scorke

 

enough OT already ?

 

The 40r set-up had a primary size roughly .25" smaller is diameter. That does wonders for spooling up a turbo faster.

 

And it was on a 2.3L... but all that doesnt matter in scorkes world... in his world he is the smartest person on this forum and knows all... proven results dont mean anything