Later model crank, rods and pistons query

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rvrftw

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Joined
Jul 13, 2007
Messages
250
Location
Hobart, Tasmania
Can a later model (i.e. evo 7) crank and rods and pistons be used in a evo 2 engine?
As I can get a complete forged kit to suit an evo 7 for a steal and was wondering if I could use it?
 
awesome, thanks for that.... i thought i read somewhere that the conrod bearings were different, so I wasn't sure whether they could be used or not.
 
I run Evo 9 crank, Evo 8 rods, pistons and valve springs in an Evo 2 motor. Just double check combustion chamber CC's and head gasket thickness to check the comp ratio.
 
The thrusts on second hand Evo 5 up cranks are always mint because the pull clutch uses the opposite side as the thrust surface when used in 1-3
 
I managed to get a stock 6.5 crank (used), Manley Turbo Tuff Rods (new) (for 4-9), and AMS pistons (new) (for 4-9) for $800.
Does anyone know whether I should be running early evo Main Bearings or Late? Also for conrod bearings, should I be running early or late model?
 
conrod bearings are the same 1-9

and get main bearings to suit your block (only difference is the thrust)
 
Dont kid yourself, EVO 5+ also get crankwalk if you have a really heavy duty clutch installed.
His OEM crank suffered crankwalk so he bought into the hype of using a later model crank.
We received an EVO 5 or 6 crank from an engine dismantler and it already had crankwalk.
Then i think we got a replacement EVO 5 crank from NZ and put it into my brothers EVO 1 engine - it crankwalked with only about 30k on the clock.
This time he's going to use an aftermarket forged crank and investigate better bearing designs.
Here's a nice pic of the EVO 5 crank for you :)
 

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well actually I didn't buy into any hype. A guy I know changed his mind and went a 2.3L stroker, and therefore had his old crank and rods/pistons for sale cheap.
I'm not sure if my current engine has crankwalk, as the symptoms are that it is currently suffering massive blowby, and is making a constant ticking sound (that is a different sound to lifters). This all happened after I hit a wallaby and it cracked the oil cooler, which caused oil loss. Unfortunately I wasn't able to pull over for about 10kms.
Therefore I am rebuilding my engine, and I figured that I might as well put a newer crank in.
 
Have the oil squirters been checked or replaced Rob?
Yeah soaked them clean and blew them out with some compressed air til the check valve closed.
I didnt have an air pressure gauge to see how much psi exactly, but they were definitely operational.
 
I dont chamfer, just use two sets of mainbearings as above, fully groovy.

I am also a big believer in the check valves bleeding off pressure to the thrust as they feed from the same gallery.

previously I had fitted new check valves, now I just throw them in the bin and block the holes.
 
ah so no more oil sprayers squirting up under the piston skirts. Is that perfectly OK to do with forgies? I know lots of engines dont run squirters but in your opinion George if building a 7-bolt block again, would you recommend guys with 7 bolt evo engines ditch the squirters and run a full grooved main bearing instead? After 2 spun big end bearings and 2 replacement cranks as a result of crankwalk being the cause, third time build for my brother has to eliminate the problem so it doesnt happen again lol
 

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