2g pistons or evo 9 pistons

[sharky559]

ive been doing some reserch on evo 9 pistons on 7 bolt rods and i really got confussed. people are saying to stay with 2g pistons an d some say to upgrade to evo pistons. could some one help with this.

 

[dsm03]

Id assume it evo9 pistons would run you lower compression?

 

[EglTalon_ESi]

are evo pistons going to make that much of a difference? if not don't bother paying the extra $$ for it.

 

[VETTE_50_TH]

2G pistons are 8.5:1. Evo pistons are 8.8:1 They also have coated skirts like a wiesco piston and are forged. They are good pistons and capable of around 500-550 HP. You can pick those pistons up for around 100-150 and rings are around 150 dollars. Def worth it.

 

[herms99gst]

From what ive read and the little bit of research ive done mysef, the evo piston is a partially forged piston, its not fully forged piston. The head i believe is forged and can take a little more abuse. Its a direct fit on the 7 bolt rod but the 6 bolt rod can be used as long as the wrost pin hole is re sized to accept the 7 bolt wrist pin. Idk for the price get u some mahels and be done with it.

 

[VETTE_50_TH]

6 bolt wrist pin= 21mm
7 bolt wrist pin= 22mm

They are not fully forged. But still a great choice.

 

[sharky559]

so evo 9 pistons give low compresion

i also read some where that you need a thicker head gasket

 

[EglTalon_ESi]

2G pistons are 8.5:1. Evo pistons are 8.8:1 They also have coated skirts like a wiesco piston and are forged. They are good pistons and capable of around 500-550 HP. You can pick those pistons up for around 100-150 and rings are around 150 dollars. Def worth it.

well in that case not a bad price.

 

[red94gsx]

Evo 9 stock compression ratio: 8.8:1.

2g stock compression ratio: 8.5:1.

I'm not sure if the evo or 2g pistons are taller, which is what will change the compression ratio. (If the 2g and evo rods are different lengths, that could also change compression ratio.)

 

[Deuce_three]

I have evo pistons. Overall height of the evo piston is a little shorter then the stock 2g piston. It sits a tad bit lower on tdc then a stock 2g pistons which gives a slightly smaller C/R then the stock 2g.

the dsmgraveyard.com has a good discription on this setup.

 

[my dreamt dsm]

I have evo pistons. Overall height of the evo piston is a little shorter then the stock 2g piston. It sits a tad bit lower on tdc then a stock 2g pistons which gives a slightly smaller C/R then the stock 2g.

the dsmgraveyard.com has a good discription on this setup.

Did you notice anything worth while? Was it worth it? J/W if i should spend some money on this!

 

[Deuce_three]

Did you notice anything worth while? Was it worth it? J/W if i should spend some money on this!

I say its worth buying. Its way better built then the stock 2g piston imo.

 

[my dreamt dsm]

I say its worth buying. Its way better built then the stock 2g piston imo.

Cool. I think I'll look into this mod down the road.

 

[WickedQuikAWD]

The evo pistons are a significant upgrade over the stock 2g piston. Coupled with the 6bolt rods, which are stronger than the 7 bolt units, the evo pistons work to provide a stronger bottom end. Although as previously stated, the 6bolt rods will need to have the wrist pin side bored out to support the larger wrist pin.

Lower compression works well with higher boost levels at the sacrifice of low rpm responsiveness and power. Higher compression is more detonation prone and requires the use of less boost or higher octane fuel... but is more responsive and creates more low end off boost power.

 

[sharky559]

can i use the evo 9 rod to are stay with the 2g rods

 

[VETTE_50_TH]

Either use the evo 9 rod for a 7 bolt motor or the 1g big rods machined out to accept a 22mm wrist pin for a 6 bolt

 

[Misterbeechy]

would 7 bolt rods fit in a 6 bolt?

 

[ezz-e]

7 bolt rods do not properly fit on a 6 bolt crank.

There is no change in compression when you put the evo9 or 8 pistons in a 2g block, they are still 8.8:1.
The evo8/9 pistons are of much more better design then the 2g's, the Piston pin was moved slightly higher on the evo's to provide better rod angle, the tops are forge and the skirts are friction coated. now the evo9 piston has a revised oil control rings to provide a smother and more control lubrication on the cylinder wall, this in hand allows the motor to rev up alot faster allowing you to reach boost much quicker. When you look at the type of technology mitsu applied to the evo you will notice they were purposely making the car rev faster so it can reach full boost much quicker. For example hallow cams, twinscroll turbo, lighter rods and piston combo, better oil control, and in the evo 9 Mivec control on the intake cam.

 

[VETTE_50_TH]

The evo 9 pistons are shorter. This was already covered. The comp goes down.

 

[ezz-e]

Were was this covered? Show me the Proof?

 

[VETTE_50_TH]

I have evo pistons. Overall height of the evo piston is a little shorter then the stock 2g piston. It sits a tad bit lower on tdc then a stock 2g pistons which gives a slightly smaller C/R then the stock 2g.

the dsmgraveyard.com has a good discription on this setup.

Right here.

 

[ezz-e]

The EVO uses the same crank as a 2g and even do the rods are a a little different(strength wise) they are also the same dimensions. 88 mm stroke/150mm Rod. Now explain to me How this will change the C/R of a piston that USES the same Deck Height and Same Bore/Stroke Rod length?

also the head uses the same bowl 47cc

 

[VETTE_50_TH]

You said it yourself, the pin height is slightly higher.

Just read this thread. Please. You are wrong.

http://www.dsmtuners.com/forums/ven...frankenstein-setup-7-bolts.html#post152241031

 

[ezz-e]

Vette I think you missing the point of them moving the pin height...
Think about it very carefully.
They moved the pin height but obviously gave the piston top more material to reach 8.8:1 making the piston much stronger.

If what you claim is true then a believe mitsu ripoff alot of evo owners when they released the specs to the evo 4g63t engine.

To the OP you should be able to get a very good set of evo pistons with rods on The EVOM forums for good price.

I would directly drop that combo into my motor and not even bother with any 1g rod combo. There are alot of stock motor evos running 10s and more then a handful in the 9s on stock blocks. STM is a good example of this. The only thing i advise you is if you plan to make more then 400tq on the rods you should look in to some forge parts at that point because the rods and pistons will not last long with that much torque.

 

[VETTE_50_TH]

If you read the article i posted, you would see you are wrong. But ok. Sure.