RB26 vs RB25

[PlATiuM]

hey this got on my mind of the other day when i read a post of someone wanting to swap out their rb25det for an rb26dett which got me think.

the motors are neally identical right? other than .1L and the twin turbo

cause if your going full out on a motor big single sure that .1L will change the spool time etc but once u get down to replacing the interals such as rods, pistions, cams, head work, etc etc there going to be the same strength right?

just a thought. also been thinkin alot of this lagg with bigger turbos :S to me lagg is how long it takes to get responce for ur get up and go when u plate the peddle.

cause say u got car X with turbo A it makes random number 300NM torque at 3200rpm than car X with turbo B a bigger one makes 430NM of torque at 3500rpm effecitivly ur going to have more power downlow compared to turbo A?

your full boost mightent be there as quick but your flowing a heap more air into the motor at lower boosts which is wat u want "same or lower boost but with more flow" just another question.

thanks

Luke.

[JimX]

the motors are neally identical right? other than .1L and the twin turbo

No!

[knore]

They are FAR from identicle.

The RB26DETT is built alot stronger than the RB25

[R31Nismoid]

knore, read what he said... once he's changed internals etc... they'd be better than what a 26 has stock if im not mistaken???

But PlATiuM, the head is different and stuff too.

[Gav]

The heads are a world apart both in design and flow capabilities.

[raist60]

Hardly a world apart. They are the same casting just cleaned up with sexier valves.

Hes saying if your gonna build a psycho engine you could use a cheaper base RB25 and do things like headwork that would negate the point in starting with a 26.

[Sydneykid]

Hardly a world apart. They are the same casting just cleaned up with sexier valves.

Hes saying if your gonna build a psycho engine you could use a cheaper base RB25 and do things like headwork that would negate the point in starting with a 26.

If you are going to replace everything then I'd start with an RB30.

[raist60]

I always look at 25/30 hybrids as starting life as a 25 then whacking a 30 bottom end under.

I wouldnt personally go buy a shitty RB30 and then buy each part to make it back into a DET. :| Personal preference perhaps

[rb25]

i thought the RB30 block didnt have the little oil squirter things that spray the cylinder walls and pistons like RB2x's?

[Abo Bob]

There is another thread on this. It's a sticky too but in it they fit the oil squirters in themselves.

[PlATiuM]

ok thanks for all your import people least my heads clearer now

[Sydneykid]

Hardly a world apart. They are the same casting just cleaned up with sexier valves.

Hes saying if your gonna build a psycho engine you could use a cheaper base RB25 and do things like headwork that would negate the point in starting with a 26.

I thought that too, until I added it up, the RB26 top end is much cheaper to get to the same power levels than an RB25. For example solid lifters, larger diameter head studs, stronger standard valve springs, 6 throttle bodies, plenum, RB26 cams are cheaper and easier to get second hand, better oil return to the sump, top feed injectors and rail are much cheaper to upgrade than side feed, coil packs, ignitor etc etc the list is long and expensive.

[666DAN]

Yeah it's a lot like comparing the R33 RB25DE with the R34 RB25DE Neo...same but different

[raist60]

SK: I can see your point. Always just taken it for granted i guess.