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I know of a few people having issues with haltech computers I could also show you a video which may change your mind about them lol. Mate id suggest spending your money on ya bolt on bits 1st cos if its 100% stock you will be VERY surprised how quickly it livens up when you get it breathing. :) If this is your 1st turbo car take my advice and do your bolt on power mods and see if you still think you need more torque ;)

this, breath in breath out Daniel son, 30 pistons maybe a resurface skim, 25 pistons .5mm 20thou, 26 pistons 2mm 80thou, the skirts are the same it's just the top height that comes down which is where the weight is saved

just remember what we're doing is arming you with info and suggestions cause at the end of the day you have to make the choice of what you want to do, it's your car

I know of a few people having issues with haltech computers I could also show you a video which may change your mind about them lol. Mate id suggest spending your money on ya bolt on bits 1st cos if its 100% stock you will be VERY surprised how quickly it livens up when you get it breathing. :) If this is your 1st turbo car take my advice and do your bolt on power mods and see if you still think you need more torque ;)

Yeah i think i am going to go with a power fc instead of haltech now.. I thought about just doing the 25 but thought well i want to put a fresh bottom end in anyway so i might as well do the 30 instead of another 25 and i can build the 30 while im driving it with the 25 in it. :D

this, breath in breath out Daniel son, 30 pistons maybe a resurface skim, 25 pistons .5mm 20thou, 26 pistons 2mm 80thou, the skirts are the same it's just the top height that comes down which is where the weight is saved

just remember what we're doing is arming you with info and suggestions cause at the end of the day you have to make the choice of what you want to do, it's your car

Awesome thanks. Yeah im taking all the suggestions in. Appreciate it you guys giving me info. :) So far my idea is get a 30 motor and put ACL bearings in it, Standard crank, Shot peen the rods, Forged pistons (not sure which ones yet) and cheap second hand 25 head (if possible) and put new valve springs in it if not to expensive and get it resurfaced,cleaned etc the usuals. Then when built i can just do the swap over in a day or so and sell the RB25 as a whole motor and make some money back.

Please feel free to correct me if im heading in the wrong path

you also need to remember the oil side of things, a good oil pump is a huge key to you engine life and the extended oil pump drive is also a good thing, if your going to be building a motor, what is going to be your power output goal? if its around the 500hp mark it would probably be safer to get a set of rods for the extra money then spending all this money on the motor with 20 year old rods.

you also need to remember the oil side of things, a good oil pump is a huge key to you engine life and the extended oil pump drive is also a good thing, if your going to be building a motor, what is going to be your power output goal? if its around the 500hp mark it would probably be safer to get a set of rods for the extra money then spending all this money on the motor with 20 year old rods.

Yes oil will most defiantly be thought about with the higher output motor but for now this one is just a basic build for daily driven car while i build the second engine. My next motor will be hoping for about 500/600hp and all those supporting mods will be done without hesitation.

some tips

rb30 block out of skyline r31

cp-spool package or nitto one or manley wit cp - don't waste time on stock rods time u prep them your buying new set

use rb30 twincam pistons - 25/26 pistons in rb30 isn't good idea decking block to much

0 deck

good oil pump - nitto or tomie

line bore hone, - ect

keep compression under 8.6:1

arp head/mians

ask for bottom end to be balanced wit flywheel and balancer

cheers

Edited by chairman

I disagree with compression ratio mentioned dont go under 9.0:1 if you want good torque off boost. 25's are tougher than you think I pumped 25psi into my car with no dramas on E85 and another guy Matt on here is putting 28psi into a stock motor also.

some tips

rb30 block out of skyline r31

cp-spool package or nitto one or manley wit cp - don't waste time on stock rods time u prep them your buying new set

use rb30 twincam pistons - 25/26 pistons in rb30 isn't good idea decking block to much

0 deck

good oil pump - nitto or tomie

line bore hone, - ect

keep compression under 8.6:1

arp head/mians

ask for bottom end to be balanced wit flywheel and balancer

cheers

Thank you all that will be done besides the compression. Il be putting more compression into it that 8:6:1 though

I disagree with compression ratio mentioned dont go under 9.0:1 if you want good torque off boost. 25's are tougher than you think I pumped 25psi into my car with no dramas on E85 and another guy Matt on here is putting 28psi into a stock motor also.

Yeah i want something over 9:0:1 at least for the off boost driving. This will be my daily car and wont be flogged day in and day out so the extra torque would be good. I would keep the 25 but i want to put a fresh bottom end in it anyway so might as well do the 30 since it will be cheaper. :) I will be running pump 98 in it for the ease of fueling up also.

im going to run 8.2 or 8.4 comp so I can push more on unleaded fuel around 500rwkw mark.

some agree high or low comp - but on 3l block under 8.6 u never have any head lifting issues that's a lot of shop have told me.

there is one rb26/30 runs 9.5comp but methanol fuel

cheers

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