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pistons for stock hp and Evo radiator

crazydriver81

Active member
Joined
May 5, 2014
Messages
33
Location
Berlin, Germany
Hi to all you Guru's out there,

as I am currently in the progress to build a 4G63T engine out of a 6 Bolt N/A 4G63 block, I will need to swap the pistons to reduce compression.

My plans are, to run a 16G Turbo with stock boost, 3G MAF and 560cc injectors, so no super high hp figures - car will be 2WD anyway, so target hp is 280.

My question, are these pistons and is the engine gasket set any good?
Ebay link
Which uprated head gasket can be recommended?


Further I checked physical dimenasions and mounting points from Evo3 and GVR4 radiators. I think that an uprated Evo 3 radiator should fit the GVR4 fine. Can anyone confirm or tell me something I might have missed? /ubbthreads/images/graemlins/confused.gif


Thanks. /ubbthreads/images/graemlins/worthy.gif
 

swe_gvr4_1991

Well-known member
Joined
Jul 27, 2006
Messages
177
Location
Sweden, Alingsås
On a budget that rebuild kit is great. In fact i am running similar pistons and gaskets on my GVR4. Started out as a budget build but still holds up and i'm on 400+ AWHP right now on my FP68HTA turbo.
 
Last edited:

89Mirageman

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Jul 5, 2006
Messages
2,502
Location
Stantonsburg, NC
Are the cylinders good or will you be boring the engine? If they are fine I'd pick up a good used set of stock turbo 4g63 pistons. I probably have a set laying around that you can have.
 

crazydriver81

Active member
Joined
May 5, 2014
Messages
33
Location
Berlin, Germany
The block will get bored and honed anyway, so used pistons are not my favourite choice honestly. I know you can get oversize piston rings from Mitsubishi but given the price I would rather go for new pistons.
 

CutlassJim

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Jul 17, 2006
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1,698
Location
Manchester, NH
If you are only looking for that much HP I would keep the non turbo pistons.
 

EMX5636

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Jun 28, 2008
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1,631
Location
Bucks County, PA
If you are set on OEM pistons, I would recommend 2G turbo pistons over 1G. The compression doesn't need to be that low anymore with todays tuning technology. You can get them new from Mitsu still at stock bore, and .020" over last I checked. Of find a good used set. Only downfall is the 1G rod needs to be bored out for a 22mm wristpin instead of the stock 1G 21mm. N/T 1G pistons can handle the power that you want, but aren't the greatest for detonation resistance.

For the money though, it's tough to beat a set of 8.5-9.0 CR Wiseco/Ross/Manley etc. They are pretty cheap anymore.


For headgaskets... if you can get a machine shop to properly finish the head surface, the OEM Mitsubishi MLS gasket works great and holds a ton of HP. But the factory composite gasket will easily take what you are asking for as well.
 
Last edited:

crazydriver81

Active member
Joined
May 5, 2014
Messages
33
Location
Berlin, Germany
Quoting CutlassJim:
If you are only looking for that much HP I would keep the non turbo pistons.



I am afraid this will not work as the compression ratio is different. IIRC it is 10.4 for the N/A and 7.6 for the GVR4...
 
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