Page 1 of 4

Info From Mitsubishi

Posted: Wed Jul 07, 2004 4:48 pm
by Black_FTOGPX
I have contacted the person at Mitsubishi who was in charge of rolling out the FTO. I asked him if he knew of any ways we could increase the performance of the 6A12 engine. And also if there were any power sacrifices made to comply with emission laws.

He has also given me some history on the FTO

See his reply below.

Hi Joel-san,

I contacted with a person who handled the FTO V6 before, to confirm if
there were any sacrifices to meet the Japan emission regulation
requirement.

The 6A12 MIVEC emission control system is almost 100% depend on the
performance of catalytic convertor.
The compression ratio of engine was increased to perform 200PS output
designed with the premise of 100 octane premium fuel.
The EGR does not actually spoil the engine output performance.
The air flow sensor system was chosen the D-jetro type to reduce the intake system air flow resistance.

Only one thing could spoil the engine performance of 6A12 MIVEC is the
exhaust system air flow resistance, caused by catalytic convertor.

Additionally, I put on the small history of GPX version R evaluation:

We originally planed to beat the Integral Type-R with performance and
maneuverability.
This means, I ordered to increase the engine out-put of 6A12 MIVEC also.
But, engineer's comment was negative. He also commented that the only one
way to
increase the engine output was engine displacement volume increase.
So, I changed the plan of GPX version R, only revise the handling
characteristics
as a Gymkhana special machine, with a specially tuned helical LSD and
harder suspension.

Posted: Wed Jul 07, 2004 11:36 pm
by FTO338
Dam does that mean all those mod we did are down the drain :?: :?: :?:

Hmmmm u wouldn't happen to know what size cat that will do the trick? :wink:

Posted: Thu Jul 08, 2004 1:49 am
by hnm738
thats very interesting info

so what needs to be done to the fto now to gain good power?

a hi flow cat

and what does it mean by increasing engine displacement volume?

.

Posted: Thu Jul 08, 2004 9:35 am
by jester
Good Job Black_FTOGPX
really great info there! and coming from a good source 2!!

So i guess then my hi flow Cat is helping me some! :)
Hope its not doing harm though... :?

oh and hnm738 when u increase the engine discplacement vol it means going up from a 2.0L to a 2.3L or 3.0L (ussualy achieved by boring of the engine- cylinders etc)

... :wink:

Posted: Thu Jul 08, 2004 11:15 am
by MADFTO
*smiles*
You must remember, back when the FTO was initially designed, 8k rpm was very high.

even in 95 when I'm guessing the version R specifications where being debated, FTO had only been in production a few years and they didn't want to modify the engine production line for a small volume release.

Anyways, you have to remember economies of scale comes into play with limited release models.

I'm surprised they didn't produce a tuned length set of headers though, I guess they took the engineers advice and didn't look into it at all.

A pity =)

Posted: Sat Jul 10, 2004 1:06 am
by hnm738
jester

how come you commented on the high flow cat "hope its not doing any harm"??????

is it somewhat bad to have a high flow cat?

.

Posted: Sun Jul 11, 2004 4:31 pm
by jester
hey hnm738! :)

Well.... there has been some speculation that hi-flow cats give minimal power gains and the link between "reduced back pressure" has also poped up.

But i think that is to do more with Turbo cars and not as a big issue in N/A cars.

Either way i love it and ain't taking mine off! :)

Posted: Sun Jul 11, 2004 6:55 pm
by Slither
actually reduced back pressure is something that effects n/a cars, basically its good to allow your car to breath better but if u go too far u loose back pressure and its detremental to your power, turbo cars u basically want to loose as much back pressure as possible!! thats why u shouldnt get too big an exhaust on a n/a car where as the bigger the better in turbo's!! :twisted:

well thats my understanding of it anyway, i could b wrong!!! :?

Posted: Mon Jul 12, 2004 1:49 am
by hnm738
so basically our cat is ok you are saying?

so no need to modify anything? as there would nt be anything noticeably different?

.

Posted: Mon Jul 12, 2004 11:20 am
by jester
Hey ethan! what up! :)

u could be right there mate bout turbos, My bad.
I thought i read somewhere that High back pressure could cause loss of engine power and economy and also cause overheating
But i guess ud to have a MASSIVE exhaust and to actually fell the reduction difference.. :?

I guess its like everything else in tunning - the idea is to find the happy medium
:wink:

Posted: Mon Jul 12, 2004 2:54 pm
by smorison
too big an exhaust on any car will reduce low down torque...

at higher RPM's N/A's like turbos will benefit from larger diameter exhausts however too big is always too big

Posted: Mon Jul 12, 2004 6:25 pm
by Slither
It depends on who u talk to about high flow cats as different people have different opinions but basically on an n/a car u don't really need one IMO, on the flip side though i don't thin u would b loosin any noticeable power having one

Posted: Thu Jul 15, 2004 2:16 am
by FTored
MADFTO Posted: Thu Jul 08, 2004 10:14 am Post subject:

--------------------------------------------------------------------------------

*smiles*
You must remember, back when the FTO was initially designed, 8k rpm was very high.

even in 95 when I'm guessing the version R specifications where being debated, FTO had only been in production a few years and they didn't want to modify the engine production line for a small volume release.

Anyways, you have to remember economies of scale comes into play with limited release models.

I'm surprised they didn't produce a tuned length set of headers though, I guess they took the engineers advice and didn't look into it at all.

A pity =)
i think there is a kit from mitsu that makes the diplacement bigger.It makes it 2.2 L. that is what is used in Moritakus Fto. The one with 550hp mivec+turbo. Btw Hi to all.

Thi was tkan from Ftooc:
Patt wrote:
--------------------------------------------------------------------------------

Right Mitsi have parts as standard for two re-bores as I discovered when doing my re-build. IIRC the largest took it to 2.3 - but don't quote me on that! and I didn't look any farther as I needed the engine back in the car asap plus couldn't even bring myself to look at the costs of the pistons etc.!

Posted: Thu Jul 15, 2004 9:48 am
by Black_FTOGPX
I have asked My contact about this.
Looks like they do supply over sized pistons and rings.

I am waiting on the part numbers for these so we can price them up.

Here is his reply

A engineer handled the 6A1 commented that the limit of bore size increase
potential of 6A12 may
up to 2mm in diameter.

He also commented that MMC supply 1mm over-sized piston to match the
overhauled engine block.


So, if you could purchase the over-sized pistons, the capacity might
increase in 50cc, with
1mm bore size increased block. The piston rings to fit the 1mm over-sized
piston are also exist.

Posted: Thu Jul 15, 2004 12:01 pm
by salacious
From the Mitsubishi CAPS CD
MIVEC engine Pistons
STD SIZE P/N MD316711
O/SIZE 0.50 P/N MD323689
O/SIZE 1.00 P/N MD323690

non-MIVEC engine Pistons
STD SIZE P/N MD316698
O/SIZE 0.50 P/N MD323676
O/SIZE 1.00 P/N MD323677

With a bore of 78.4mm and a stroke of 69.0mm, the std engine size is 1998cc.

I'm guessing that the oversized pistons increase the radius by 0.5mm (1mm diameter) and 1.0mm (2mm diameter). This means that they would increase the capacity to 2049cc and 2101cc respectively. If my maths are correct :roll:

Brian

Posted: Thu Jul 15, 2004 12:15 pm
by Black_FTOGPX
Would any technical “goo-roo’sâ€

Posted: Thu Jul 15, 2004 12:29 pm
by MADFTO
That's bascially it I believe, well you need to do the block and the head. Since you're not changing the stroke at all, you just need to bore out the cylinders to allow the pistons to fit.

Mind you, you're probably want to remap the fuel mappings to compensate a little, but with such a small change in each cylinder, I'd think the ECU would compenstate for the extra air you're pulling in automatically.

I'm assuming all the other aspects of the pistons stay the same, only the diameter of the piston head is increased.

Posted: Thu Jul 15, 2004 12:31 pm
by wildfaye
I am seriously interested in this!

what sort of prices n parts are involved in this!
And what sort of performance gain will we get by boring out?

Btw, I am in Spore!

Cheers!
Sam

Posted: Thu Jul 15, 2004 1:07 pm
by smorison
if you can get to 2100cc i would say probably a 10-15% increase ...

it just depends on how busy the injectors are to how much the whole customisation costs cause if you have to increase the size of your injectors that's an extra grand plus fitting easy

Posted: Thu Jul 15, 2004 1:23 pm
by wildfaye
Ic, so the block looks the same...onli internals bored with bigger pistons.

100cc equates to 10-15% more power, requires bigger injectors and fuel pump, mabe a upgrade ecu...

at the same time while boring the engine, could also port n polish the entire intake and exhaust...

does tis sound alrite from a tech dummy like me?