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DaGr81

By DaGr81,
in Engines & Forced Induction

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DaGr81 Mentor

DaGr81

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I wanna do "some" internal work to the value of about $3000 (incl labour) if i do forged pistons, do i need to do the rods too or is that not necessary? Is there another option to forgies? I read once in a mag that there was another option which is better on cold start than forgies are. How much would i be looking at for pistons and which brand would be a better option, for just a street car with occasional track outings and sometimes running the 1/4

Any help, advice or websites will be much appreciated.

ta

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Blitz Grand Master

Blitz

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So, you have told us absolutely nothing about your cars modifications, or what type of engine you are planning on doing this too.

Your budget is completely unrealistic for what is effectively an engine rebuild - Pistons/rings alone will chew at least half your budget, and good luck finding a quality workshop that will do engine r & r, full disassembly, machine work and reassembly for ~$1500!

A good set of forged pistons with rings will cost anywhere from ~$1200 or so up to $3,000 depending on what you want. Common reputable brands such as CP or ACL would probably be the best for you.

Bottom line, if you want to rebuild your engine with 'forgies' and you want to do it right, be prepared to set aside $10k including parts.

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r33_racer Grand Master

r33_racer

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my rb25 acls with rings and gudgeon pins was under 1k delivered. Your rebuild will be purely based on your power goal. No need to put in whats not required.

Other option your thinking of is hypertek pistons i believe.

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DaGr81 Mentor

DaGr81

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oopz sorry, its an rb25 all i want from it is around 270 - 300 rwkw, but im in no rush, i also have seen some cast pistons which may well do the job as they are 40% stronger than standard items... (any comments?) oh ive got alot more than 3K ready for it, but like i said id rather do it slowly also i cant do without a car for long, so i was thinking pistons first with a set of gtr rods if i can do that (cryogenically treated to strengthen it) if i do pistons do i have to do the rods too?

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Devils_Advocate21 Mentor

Devils_Advocate21

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If you do pistons you dont have to do rods, thats optional, You can get your old ones race preped so to speak, and will handle you power goal fine if you do, If you want to over exceed that get rods, as this will save having to open the engine up again. hpe that answers your question, and as the others have stated, unless your doing the work yourself 3k is not enough far from enough

Piston Bores require a hone/bore for oversized pistons rings, and machine work for block plus your head work been best to get a full service done to it is anywhere from 1300 - 2k For the above

Pistons another 1300

Then you have to include labour, bearings, Gaskets, Water/oil pumps, Belts, Oil, Coolant, Theres the good part of 3k upwards

Ummm hope they answer your enquiries

Cheers

A

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r33_racer Grand Master

r33_racer

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man its unbelievable how much people get charged to get stuff done....i rebuilt my whole rb25 with forged pistons 20 thou over, new bearings all throughout, recod head with new stem seals and cut the valves and seats, decked block, new welsch plugs and faced the head and i did pretty well most of it myself except the machining, oh a cometic mls gasket as well...i think i spent max 3k that included a few new lines and hoses. Was pissed that they didnt reassemble the head...i had to lap the valves in myself and reassemble it....and i lost a collet in the process.

Workshop manual and a little time and you can save alot of money. However i wouldnt recommend it if your not confident in your mechanical ability.

For the power output your looking at mate...all you need is what i did. Probably not even that. Dont waste your time on rods, if your going for 400rwhp, maybe put some arp studs or bolts in them, unless you can find a cheap set of gtr rods.

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DaGr81 Mentor

DaGr81

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like i said guys if i dont have to get forgies to achieve 300rwkw i wont get them, but just for piece of mind id like to get something stronger than factory ive seen cast items which are 30% stronger than factory ones anyone used these? anyone with any experiece with these gimme some comments ta

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l0WRB Mentor

l0WRB

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as far as im aware (rebuilt my rb25 2 weeks ago) i couldnt find anyone in aus who sold a STD rb25det cast piston..only pistons available were forged.. 300rwkw or 200rwkw if u get bad detonation ur going to blow a piston wether its cast or forged...

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sinistaGTR Grand Master

sinistaGTR

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dont get cast get forged.....there only like 1100 bucks so no that expensive if you wanna go big later. But the thing i found with my rebuild that all the little crap like head gasket, gasket kit, bearings, timing belt, idler/pulley, water pump tensioners and all the little bits and pieces you made need here and there all cost you money. like with my gf wrx were rebuilding now found out the clutch was stuffed aswell so theres at least another 500 on my rebuild for that.

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khunjeng Veteran

khunjeng

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man its unbelievable how much people get charged to get stuff done....i rebuilt my whole rb25 with forged pistons 20 thou over, new bearings all throughout, recod head with new stem seals and cut the valves and seats, decked block, new welsch plugs and faced the head and i did pretty well most of it myself except the machining, oh a cometic mls gasket as well...i think i spent max 3k that included a few new lines and hoses. Was pissed that they didnt reassemble the head...i had to lap the valves in myself and reassemble it....and i lost a collet in the process.

Workshop manual and a little time and you can save alot of money. However i wouldnt recommend it if your not confident in your mechanical ability.

For the power output your looking at mate...all you need is what i did. Probably not even that. Dont waste your time on rods, if your going for 400rwhp, maybe put some arp studs or bolts in them, unless you can find a cheap set of gtr rods.

ppl like me pay for it cos I dont have any time to spent building engines.. my mechanic does that.

However looks the good from what you have done. What sort of power are r u running?

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