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hey guys,

i am putting together a rb25 just for street use.

At the moment my current setup on my current motor is

3071R

plasmaman

6 boost manifold

all supporting mods exhaust, fmic, injectors, pump, vipec. etc

I have got another Rb 25 that i am about looking at assembling,

its only done 70 thousand kms, i've pulled it apart and all bearings, rings, piston clearances are within factory tolerances.

i am looking at freshening it up with:

Genuine nissan headgasket

genuine nissan bearings, mains, thrust and big end bushes.

Cosworth Forged pistons (standard bore size)

re-using standard head bolts and rod bolts.

I'm going to upgrade my 3071R to a 3076R,

looking to push about 300 rwkw. and still maintain drivability and a reliable motor.

anything else that you guys recommend while i have got the engine apart?

i'm not sure what kind of psi is needed to get to 300rwkw, but i believe the standard headgasket and head bolts are up to the job.

Are forged pistons overkill for the job? i don't mind using standard pistons.

if there is anything else that would be a good idea to do while the engine is apart. ive searched through the forums already, maybe there is something i have missed

cheers

From the reading I have done from people and there results and how theve built it I would say the idea you got going at the moment is right for the 300kw mark and personally I would upgrade the pistons and the headbolts just for peice of mind.

To run 300 you would probably be running 19-20 psi with the 3076 so in regards to head gasket I would probably go for something aftermarket as most I have read are running about 18psi with standard one. I am no expert in the department as have not built my own motor but thats just what ive gathered in my research.

its probably a good preventative measure to replace them with arp head studs,

Standard head bolts look to be Sturdy and high quality tho.

Ive looked into an mls head gasket, i'm undecided as i don't really want to get the block decked just to put one on.

anyone else put a mls headgasket on without decking the block and giving a quick clean up with a wizzer and some flap wheels?

i just wasn;t to sure how tolerant they were compared to standard style headgaskets.

hey mate im building mine now slowly and aiming for simular figures. was only 85 for big end studs and head bolts 250 from memory. worth investing in anyway. wouldnt worry about stock headgasket unless stock boost. i went king bearings but nissan ones are good

as for the comment about getting block decked its not really that expensive unless you dont want to strip it right down. but if its out go 4 it. was quoted $260 for bore out 20 thou and hone. $82 to acid bath crank and polish. $82 to deck/mill block and acid bath. ended up getting that all for $250 mates rates but you never know if its been hot before and warped etc

hey mate im building mine now slowly and aiming for simular figures. was only 85 for big end studs and head bolts 250 from memory. worth investing in anyway. wouldnt worry about stock headgasket unless stock boost. i went king bearings but nissan ones are good

as for the comment about getting block decked its not really that expensive unless you dont want to strip it right down. but if its out go 4 it. was quoted $260 for bore out 20 thou and hone. $82 to acid bath crank and polish. $82 to deck/mill block and acid bath. ended up getting that all for $250 mates rates but you never know if its been hot before and warped etc

machining is cheap, i thought i was having a good run on the stock head gasket atm seems to be good on my current standard motor @20+ psi

Do it once, do it right. Don't re-use the factory head bolts, rod bolts or the factory pistons.

I will prob go the rod bolts aswell as a the arp head bolts. Standard Rods look quite robust.

put a crank collar on,i wish i had now im taking the motor out again to do it.

With this crank collar. i take it the factory crank collar only goes iunto the pump drive 5 mm or so. aftermarket collars go into the oil pump 12mm(?). so less chance of slip or braking

do you have to rebalance the crank with this new crank collar? still fine to use the factory oil pump with the upgraded crank collar?

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