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Is it worth stroking a 25 to 2.7 with the 26 crank rods pistons and etc or would it be more feasible to just build a 26?

What would be the advantages and disadvantages using the 25?

Car is a 32 sedan and will hopefully be used for a bit of circuit and road use.

Am open to all advice. AAANNNNDDDD GO...

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stroked 2.7 RB25 would be good, but remember (unless you use a neo 34 head) it's still gonna have hydraulic lifters, and wont be as rev happy/efficient as a 26 head.

That said both options make great power, there's really nothing to win one over the other...

considered a 26/30 or 25/30?

stroked 2.7 RB25 would be good, but remember (unless you use a neo 34 head) it's still gonna have hydraulic lifters, and wont be as rev happy/efficient as a 26 head.

That said both options make great power, there's really nothing to win one over the other...

considered a 26/30 or 25/30?

Mine revs to 9000rpm, hydraulic lifters and Tomei springs :dry:

Mine revs to 9000rpm, hydraulic lifters and Tomei springs :dry:

Hmm fair enough!

I stand corrected :D

That is sorta true as a general rule though right? Solid lifters are more efficient and more rev happy than hydraulic types?

Hmm fair enough!

I stand corrected :dry:

That is sorta true as a general rule though right? Solid lifters are more efficient and more rev happy than hydraulic types?

Yes, and you can get a solid lifter conversion kit to make the RB25's solid, like the Neo's, but for the cost it wasn't worth it. Instead we opted for the valve springs, and hasn't missed a beat. To be honest those, on most engine setups I've seen the engine is out of efficiency before 9k.

I've considered a couple of combos but for me the 2.7 stands out a little more because its different. The donor motor is a 33 series 1 as far as i can tell. The combo i'm looking at is

34 crank

nitto rods

JE Pistons

nitto oil pump

272 cams with springs

sard 750's

gt35 with 6 boobs and whateva else is required

rb30 bottom end is hard to pass up, alot cheaper than stroking the rb25 and if anything stupid goes wrong the bottom end is alot easier to replace. Wont need such a large duration cam as youll have more torque earlier and wont need to revv as much... i find my gt35r is still a bit laggy for my liking on the 3litre, but heaps better than the 25.. a good 700rpm, if you can wait until the end of the year ill have mine rebuilt and back on the road.. can take you for a spin and see if you like it.

Jarrod

+1 for the 30DET, you're rebuilding anyway so go splash $100 on an RB30E, buy pistons and rods to suit and longnose the crank, use your 25 head and the cams you were planning on. Go the GT35R with .82 (minimum) or 1.06 housing.

If you go the 30 make sure you let Kyle know it's a 30 in a 32gtst so the manifold will fit. He'll also want you to get a 50mm gate.

Bart, have you got a VQ in a car in your shop? will call past and have a sticky beak if you do

And Bubba by longnose the crank is that the collar you stick on it to suit the oil pump?

Edited by turboedsloth

Yeah I mean put a crank collar on so you have the long oil pump drive like 33/34gtr cranks.

Personally I'm welding the snout of my crank and machining back to suit my specific gears as opposed to using a generic collar that's toleranced to suit a variety of gears. Some people don't like the idea of welding the crank though so it's an each to their own thing. The reason I'm going down that path is that I firmly believe the common destruction of gears is due to the poor tolerancing between drive and gears.

i have the 0.82 exhaust housing on the gt35r

i quite like your idea there bubba.. i had a crank collar fitted on my car and my oil pump failed in a very strange way... the outside gear ended up in about 10 bits, i am hoping to rectify the problem with a better balance, harmonic balancer and a billet pump, i might have to check the clearance between the collar and the pump.. one of the engineers i took my pump to said it looked like there wasnt enough clearance axially for the gears.

Jarrod

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