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Rb25De Rebuild

RedDrifter
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GTScotT Grand Master

GTScotT

Posted
Posted

Which isnt something you would want to begin with lol.

I think power and combustion temperatures would be relevant to eachother, so I would say that they are somewhat power dependent.

I'll stand by it.. The factory make up is fine for the suggested setup and will save a packet.

bubba Grand Master

bubba

Posted
Posted

Forged pistons don't allow for higher combustion temperatures persay, you could make 6-800hp on factory cast pistons as long as there is no det. Induce det and then you will have a problem with cast pistons a LOT sooner than you would with forged pistons.

So I get what you're saying, but I don't wholeheartedly agree :P

But yeah, factory setup with a few critical mods (oil supply/return etc) should see it live a long healthy life.

Oh and I'm still baffled by the 3L will be too torquey comment :blink:

RedDrifter Experienced

RedDrifter

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Posted (edited)

Forged pistons don't allow for higher combustion temperatures persay, you could make 6-800hp on factory cast pistons as long as there is no det. Induce det and then you will have a problem with cast pistons a LOT sooner than you would with forged pistons.

So I get what you're saying, but I don't wholeheartedly agree :P

But yeah, factory setup with a few critical mods (oil supply/return etc) should see it live a long healthy life.

Oh and I'm still baffled by the 3L will be too torquey comment :blink:

I have no issues with the rb30 set up other than it not what I wish to do. I think too torquey would be more down the lines of a LS3 (I did look into this a bit back but I threw that idea into the too hard basket.). I'll take that comment back on the RB30. but that's all you getting out of me on that one.biggrin.gif

I want forgies to have a better chance against det and it will allow me a bigger turbo if I wish down the track.

Edited by RedDrifter
bubba Grand Master

bubba

Posted
Posted

I have no issues with the rb30 set up other than it not what I wish to do. I think too torquey would be more down the lines of a LS3 (I did look into this a bit back but I threw that idea into the too hard basket.). I'll take that comment back on the RB30. but that's all you getting out of me on that one.biggrin.gif

Fair enough, and an LS3 conversion, while cool, would need custom bellhousing adapters and all sorts of crazy shiz!

Just to address your point of it looking like an RB20.. I run RB25 cam covers but the RB20 timing belt cover (says RB20 on it), unless you were very experienced with RB engines (or looked at the engine number), there is no way you would tell it wasn't an RB20 :P

I want forgies to have a better chance against det and it will allow me a bigger turbo if I wish down the track.

Good call, I would put some decent aftermarket rods in there while you're at it too.. build the bottom end properly from the get go!

Forged pistons

Aftermarket rods (usually come with ARP bolts)

Stock main and head bolts are fine

ATI balancer

Balance all the up/down/rotating bits

People have different opinions on bearings, we run NDC bearings

Stock oil pump (if it's old old, shim the pressure relief valve 1-2mm)

Restrict the feeds to the head

If the car is driven on the street at all, stick with the standard water pump (heaps of discussion threads on this)

Have good times.

  • 10 months later...
StevenCJR31 Veteran

StevenCJR31

Posted
Posted

25DET intake wont bolt onto the R32 25DE head AND the R32 RB20det intake manifold has smaller ports that the R32 RB25DE head, i have all the above parts and was looking at doing something similar myself, easier to source a R33 RB25ET engine instead !

KiwiRS4T Grand Master

KiwiRS4T

Posted
Posted

Ok you all win I decided to go an RB30.

I picked an RB30 bottom end up for $50 yesterday.

Appears to be in quite good nick.

Well done!~ Congratulations on being prepared to change your mind - I'm sure you won't regret it!

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