The first thing you notice is that the power output is not remarkable. Even with MIVEC variable valve lift & timing on both the intake and exhaust camshafts, the 4B11 (developed in conjunction with Hyundai and Daimler Chrysler but with Mitsu-specific camshafts and cylinder head for the Lancer) only develops a pedestrian 152hp.

That's not bad, mind you... considering that the new Honda Civic K20Z, Alfa 156 2.0TS and BMW 320i produce roughly the same 150-160hp. The new Camry 2.0G and Nissan Cefiro 2.0 outputs slightly less at 140+hp. So, it's respectable, but it's not spectacular by any standards.

Then you'd notice the 4B11 engine has a 86mm bore and 86mm stroke. The legendary 4G63 which served 9 generations of Lancer Evos as well as several generations of Galant VR4 rally cars - was under-square with a bore of 85mm and 88mm stroke. Why the perfectly square 4B11 after decades of rally-tested under-square 4G63?

In my opinion, the answer lies in a small tuning workshop in the heart of Kepong, Malaysia - called Forge Racing (formerly KCK Racing). It is the birthplace of the first street legal Mivec turbo engine... ever. In 2000, several years before Mitsubishi rolled out its first Mivec turbo in the Evo VIII - Forge Racing crossbred the block of a 1.8 litre 4G93 turbo and the cylinder head of a 1.6 litre 4G92 Mivec. That resulting 1.8 engine output over 300hp at 8000rpm with a boost of only 1.5bar. But what was the main lesson learnt from that little pocket rocket?

It was that if the overarching limitation on any turbo engine is [small] displacement... then more turbo boost is NOT the answer. It rapidly gets to a stage where there's too much mechanical stress, too much heat and petrol from a regular gas-station produces problems rather than power. The answer was more revs! Don't overdo the boost. Keep it sane, keep it steady and turn up the revs. The power will follow.

Squaring the engine by enlarging the bore and shortening the stroke usually means one thing... more revs. So... if Mitsu wanted more revs, then why the peak power at a lowly 6000rpm still, and low-ish compression of 10.01 from the 4B11?... My speculation... headroom.

My thinking is that Mitsubishi had basically extracted all it could from the 4G63 by playing all the turbo tweaking cards available to it. At roughly 300hp, there wasn't very much more they could do with the 2 litre warhorse without making it too uneconomical to manufacture/ warranty and too unstreetable with turbo lag, fuel consumption and inconvenient emissions. Ralliart UK's FQ320 was possibly the limit of streetability. The FQ400 was best left for the track and Sunday drives. Subaru's STi has traditionally mirrored the Evo's evolution (pun intended), and it is very telling that even they have recently migrated the STi from 2 litres to 2.5 litres.

I reckon Mitsubishi figured they needed a new high rev engine that provides room to increase power, but without the attendant downsides of excessive boost pressures and big turbines. So, in walks a perfectly square engine. The 152hp in the everyday Lancer might be just be the tip of the 4B11's proverbial horsepower iceberg. And 152hp is a very, very comfortable minimum to start from. The 4B11 turbo in the upcoming 2007 Lancer Evolution X is rumoured to have 300+hp straight out of the factory... and we'll soon see if Mitsu agrees that raising the revs is the best way to get there (since they aren't increasing the displacement).

I also strongly believe that Mitsubishi realises that it has been missing out on a lucrative mid-range performance market niche ie. the 180-250hp hot compact segment. Since the last 200hp Lancer GSR rolled off the production lines in the mid 90's, Mitsubishi has not had an answer to the Subaru WRX, VW Golf GTi, Ford Focus RS, Civic and Integra Type R, Mazda 6 MPS etc. A new baby Lancer Evo would be timely... and simple to achieve with the 4B11.

Info from here:
http://sean-the-man.blogspot.com/200...fications.html


I still see big things from these new lancers..

 

Awesome post.

 

Thanks man.

 

112 views only 1 comment?

 

nice to know man,thanks,good reading

 

I feel smarter reading all of that just now. It be nice to see those gains on an N/A setup..

 

oh i read but i didnt comment becasuse the first reply already explained how i felt.

awsome post x2!

 

Thank you, Joker.

Long as they don't forsake the big evo for the little one.

 

How can we comment?

I kinda went "wow" in my head and then drooled a little.

 

I did the same, it just made me even more happy about my purchase...cause I want the power...POWER!!

 

It's just going to be interesting to see if we can do anything to harness all of this potential.

Now I'm even more interested to see how the Works ECU-reflash R&D goes...

 

i'm torn. i used to think the same thing. i made a post a while ago about the very same subject. about how they most likely changed the bore/stroke to a perfectly square configuration for more revs. about how the valvetrain is now a cam on bucket design and how that makes for a more rev happy valvetrain....

...then the BM video was leaked and the brochure was leaked....

now we know that the redline is STILL 7000 rpm. what we don't know (for now) is the rod ratio. the 4G63 was a brilliant motor because despite being undersquare it had an ideal rod ratio of about 1.7

is the 4B11 just a "destroked" version of the world engine? now i'm inclined to say yes. i don't think mitsu really cares about the "tuner" aspect of the evo. no car is ever built with the intention of having the buyer mod the car. i think mitsu wants to build a sportscar with mass appeal. not what tuners want, or what tuners can do with the car. to me it's pretty obvious the 4G63 is basically maxed out. you can't go any further with it and still have a 10 year powertrain warranty. the 4B11 is a fresh new engine used to MIMIC the 4G63's performance with a few new things added in to make it better. the most novel aspect of the 4B11 is the weight which mitsu doesn't shy away from mentioning at every chance. to me mitsu is not waging a HP war. they are content with ~300HP. what they want to focus on is the drivetrain (SST and S-AWC) and the driving experience (less lag, chassis rigidity, etc.)

 

Isn't that the market segment they aimed for with the eclipse? Some people might not agree with the direction they are taking there, or think they missed the mark, but I haven't seen them market it as anything else.

 

lol the evo hasnt been released yet lets seee what she can do before we make any unfair judgements on its younger half brother lancer.

I want to see what she can do

 

I thought you want a longer stroke for more torque vs a square engine which can give you higher revs but very low stroke(low compression ratio)?