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looking around 3 - 4 K for the Halfcut with running gear labour depends can do most urself and just get the wiring done

Ask KYP - Ben he will be one of the best to ask

Edited by RICCA

$50 for a bottom end, $200 for a set of bearings, use your neo head (gives a nice compression ratio with stock pistons), use as much as you can off your current RB (oil/water pumps etc etc). If you can do a lot of the work yourself (read: all of it) then it can be done for very cheap.

There is a guy running 10s in a 33 over east on a standard rebuild and RIPSNZ push some serious power out of standard build bottom ends! Keep the rev limit sensible and it will survive.

Even with a standard setup, I reckon you could slap together a standard build 30 for under $500 and it would be fine with the only large outlay being an ecu.. it will run on a stock ecu but will most likely hit R&R very quickly (mine did and maxxed the afm almost straight away).

You have the benefit of a neo turbo aswell so it shouldn't choke up as early as mine, would probably see you through to 6500rpmish which is good because you don't want the rev limit set much over that.

OK just keep in mind if you use the same turbo you have, you won't get more "power" so to speak.. you will get more torque (or same torque earlier).

e.g. my 30 makes the same "horsepower" as my 20 did, but a lot sooner.. 183rwkw @ ~4600rpm instead of ~6500rpm which makes for a LOT nicer car to drive on the street. The other benefit of more capacity is being able to spool bigger turbos sooner than a 20/25 :P

Don't even need to change the manifold. You can go an internal gate GT30R, will bolt onto stock manifold and be good for 300rwkw. Any bigger and you have to start looking at high mounts etc.

Hell, this is Cubes' engine bay (he's an RB30DET guru in SA), GT30R making 300rwkw and looks stock as a rock!

gallery_382_2658_61763.jpg

Injectors, ecu and afm if not going for a map based ecu.

I opted for a GT35R so I have headroom for more power later (also sized my injectors appropriately), but this means I have to go highmount and external gate :wub:

Hrmm Sounds pretty good or

could just save alot of the $$$ and do the the highmount convo i guess

but for now see how i go :wub:

That would be the better way to go about it, even GT30R on stock manifold but still a 25. When the 25 dies then look at a 30 as part of the rebuild, if you're rebuilding your motor there's not much difference at all to make it a 3L :(

if i buy rb30 bottom who would sells rb25 head / intake separate from 25 bottom's??? u'd think not many people would sell separate. could i use rb20 intake manifold and supporting gear???? is rb20 bolt on gear straight bolt up too rb25 top end gear????

if i buy rb30 bottom who would sells rb25 head / intake separate from 25 bottom's??? u'd think not many people would sell separate. could i use rb20 intake manifold and supporting gear???? is rb20 bolt on gear straight bolt up too rb25 top end gear????

If you want your rb20 intake manifold to bolt on then you need to use an R32 RB25DE head, the R33 RB25DET heads have a different bolt pattern.

With an R32 RB25DE head you can use everything off the RB20 but you need to modify the power steering bracket (cut back the top boss so it can bolt onto the RB30 block instead of the head, that goes for whatever head you're using).

Easiest, cheapest, most straight forward swap into a 32 is with the R32 RB25DE head but it then limits you as far as intake options go, there's no GReddy plenum that will fit etc etc. I had to go for a custom plenum.

Edited by bubba

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