sparky N

iTrader: (4)

I know this has probably been asked before but just wanted some opinions or experiences to clarify the best route, I'm about to embark on a built 2.5 for my sti 5 type r, I've already sourced a very low mileage ej257 short motor and a set of eagle rods, i'm planning to fit race series acl bearings main and ends and use the heads from the sti 5 engine.
I'm hoping to make a reliable 450/450 with this set up and am planning to do as much of the work myself, Have looked at using the drop in wisecos from lateral are these the best bet or are there more economical alternatives ie mahles or je? and do these come in a drop in type?

Also is porting of my sti 5 heads a good idea and has anyone used RCMS for this?

Any help, Information or ideas greatly appreciated.

Cheers Neil.

sparky N

iTrader: (4)

Anyone?

SSCJAY

As your building the engine from scratch you would be best off having the bores honed to suit the new pistons, get the bores checked for wear size etc before you buy new pistons. you only normally use drop in pistons when you are not going to split the block. Wiseco are probably the best VFM.

As for porting the heads I would spend your money on other things, really isn't necessary for 450/450 on sti 5 heads.

merlin24

iTrader: (1)

Have to agree with SSCJAY - the bores and new pistons must be measured to determine the correct piston to bore clearance - typical Wiseco clearance is 0.003" for their nice shiny Forged Pistons.
The Standard piston to bore clearance on the EJ257 goes from -0.0004 to 0.0004" Yes thats less than minus half a thou - thats down to the Hyperthuretic pistons Subaru use as standard.
So there is no way your going to fit Forged pistons and get the right piston to bore clearance without having the piston skirts "pick-up" when it comes up to temperature.

Mick

sparky N

iTrader: (4)

Thanks for the replies, I thought the wiseco drop ins were a pretty safe bet but have heard of excessive oil use in some cases? If i am going down the hone to fit route what type would be recommended?
Cheers, Neil.

DJ_Jon

iTrader: (7)

Wiesco do the hone to fit type I believe, the other options are Wossner, JE, Cosworth... etc