Cheers.

Sean.

Mate,

See post #129 in this thread: 6g75 differences compared to the 6g74 (http://www.aussiemagna.com/forums/showthread.php?t=64660&pagenumber=)

Pics copied below anyway:

http://www.aussiemagna.com/forums/attachment.php?attachmentid=39219&stc=1&thumb=1&d=1253100510 (http://www.aussiemagna.com/forums/attachment.php?attachmentid=39219&d=1253100510)http://www.aussiemagna.com/forums/attachment.php?attachmentid=39220&stc=1&thumb=1&d=1253100510 (http://www.aussiemagna.com/forums/attachment.php?attachmentid=39220&d=1253100510)

Thanks mate.

Christ - when I heard the top of the slugs was fragile I didn't think it would be that bad.

Turbo?

Piston says no.

Tougher pistons is a given when turboing an NA engine anyway

That depends entirely on the stock piston.

Not required in many many applications.

My last motor (not turbo to begin with) with stock slugs went to over 800hp (26psi + 100 shot of gas), and it was a rod that let go - the slugs were just fine.

Providing you stay on top of mixtures and timing a stock slug with decent thickness crown and ringlands will cope no worries.

The ones above however are no good unfortunately.

That depends entirely on the stock piston.

Not required in many many applications.

My last motor (not turbo to begin with) with stock slugs went to over 800hp (26psi + 100 shot of gas), and it was a rod that let go - the slugs were just fine.

Providing you stay on top of mixtures and timing a stock slug with decent thickness crown and ringlands will cope no worries.

The ones above however are no good unfortunately.

I agree - good tuning is what makes or breaks a motor, HOWEVER I have not seen a single Mitsubishi motor cope with more then 300HP for an extended amount of time with NA slugs - this goes for 6G72/74/75.

;1315030']I agree - good tuning is what makes or breaks a motor, HOWEVER I have not seen a single Mitsubishi motor cope with more then 300HP for an extended amount of time with NA slugs - this goes for 6G72/74/75.

At the flywheel?
(No probs for the 6G75.)

At the flywheel?
(No probs for the 6G75.)

From what I've been reading for many many years, these are ATW figures from mostly 3L N/A > TT'd motors. (about 220kw at the treads)

Here you go...a real 6G75 stock piston.....


side view


http://img704.imageshack.us/img704/4895/6g75pistonsideincrod.jpg (http://img704.imageshack.us/i/6g75pistonsideincrod.jpg/)

piston diameter


http://img100.imageshack.us/img100/4889/6g75pistondiameter.jpg (http://img100.imageshack.us/i/6g75pistondiameter.jpg/)

its a 6G74 rod on a 6G75

http://img814.imageshack.us/img814/3558/6575rod6g74rod.jpg (http://img814.imageshack.us/i/6575rod6g74rod.jpg/)

piston top

http://img202.imageshack.us/img202/2630/6g75pistonfac.jpg (http://img202.imageshack.us/i/6g75pistonfac.jpg/)

pin

http://img811.imageshack.us/img811/5715/6g76gudgeon2.jpg (http://img811.imageshack.us/i/6g76gudgeon2.jpg/)

pin again

http://img191.imageshack.us/img191/7651/6g75gudgeon.jpg (http://img191.imageshack.us/i/6g75gudgeon.jpg/)

skirt


http://img46.imageshack.us/img46/3343/6g75skirt.jpg (http://img46.imageshack.us/i/6g75skirt.jpg/)

One thing that strikes me looking at that slug/rod assembly is the height of the gudgeon pin.

For a big HP forced induction version of the 6G75 you'd probably want to use a slightly shorter rod so you could increase the thickness of the crown and ringlands.

Mind you I'm talking 30+psi boost pressure.

One thing that strikes me looking at that slug/rod assembly is the height of the gudgeon pin.

For a big HP forced induction version of the 6G75 you'd probably want to use a slightly shorter rod so you could increase the thickness of the crown and ringlands.

Mind you I'm talking 30+psi boost pressure.


I'm running 7.5 psi now with stock internals and aiming for 10-12 psi performance with plenty of margin for safety.


At 7.5 psi a 3.8 litre v6 is a weapon indeed...

15 psi makes it equivalent to an 8 litre NA..

but your 30 psi is beyond the scope of sane people...:happy:

You're right - my points of reference are pretty screwed up these days

Last motor package I did made 540rwkw, and the rebuild it's currently undergoing should knock out 850+rwkw (target is 1000 rwkw, but I dunno how close I'll get)

I reckon 15psi through a 6G75 in a FWD chassis will probably be the practical limit - much more than that and it'll probably just axle tramp to 100km/h plus, and the mods required to get rid of tramp in a straight line will cock up the cars general ride quality.

It'll be interesting to see how the trans copes. Just thinking about it, talk to MV automatics here in adelaide about fortifying the auto. You may want to up the line pressure and increase the shift rate.

How are you planning to feed it 15psi? Centrifugal blower (yuk), PD blower, or turbo?

Given a link to this topic. I would like to clarify. Measurement of the piston are produced using a micrometer with 2 digits after the decimal point. I want to say, piston not round. The measurements are conducted at the height and width of the 4 locations. Here is a drawing of a T-shaped piston. But any piston can be measured by the scheme. 1. Information about the car and the engine
Model of car: *
Model of car: *
Year of graduation: *
Model (code) of the engine: *
The number and arrangement of cylinders: *
Number of valves per cylinder: *

2. The requirements for the engine
The volume of the engine, cc: * V
Cylinder diameter, mm: * D
Piston stroke, mm: * S
Boost: * There Are No
The boost pressure, bar* P:
Compression level: * e
Maximum rotation frequency, rev/min: * n

Maximum engine power, h.p: * N

3. Operating conditions
Mode of operation: * Road-
Participation in drag-racing championship: * No Yes
Rationale for the manufacture of T- pistons
for road use:
Class, a group of sports competitions,
the availability of the technical requirements:
http://s60.radikal.ru/i168/1112/6a/6c2005b9757a.gif (http://www.radikal.ru)
The height of the piston, mm: L
The diameter of the piston pin, mm: * d
The length of the piston pin, mm: I
Compression height, mm: * H
The thickness of the upper
head of connecting rod, mm: w*
The distance between the beans of the piston, mm: * B
The width of the top
head of connecting rod, mm: * b
Planting a finger in the connecting rod: * Press Floating
Displacement of an axis of a finger from the axis of the piston, mm: a
The number of piston rings on the piston: k
The thickness of the piston rings, mm: h

These data are needed for the manufacture of piston. If you do not know these data with an accuracy of hundredths of a millimeter, it is necessary to carry out development work.

5. Parameters for the calculation of crowding out (depressions in the bottom)
The volume of the combustion chamber in the cylinder head, the cc: * v
The thickness of the cylinder head gasket, mm: g*

6. More information
Comments,
additional information:
The need for the manufacture of fingers: * Leave the staff of the Manufacture of the new regular or special


7. Information about customer
Name: *
Company:
Phone: *
Fax:
E-mail: *

Only after having gathered all the information, We can make the correct piston