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Can someone please help. I have a RB30DET with RB25 head. Would like to know if RB26 cams can be fitted into a RB25 head. I know the lifters are differant (solid vs hydr) but the RB26 cams offer a bit more lift.

Has anyone done it ? Straight fit, or modifications, and would it give a worthwhile performance gain ?

Thanx.

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Can someone please help. I have a RB30DET with RB25 head. Would like to know if RB26 cams can be fitted into a RB25 head. I know the lifters are differant (solid vs hydr) but the RB26 cams offer a bit more lift.

Has anyone done it ? Straight fit, or modifications, and would it give a worthwhile performance gain ?

Thanx.

It can be done, I've had it done to mine. It entails losing the vct and some custom valve length work to set valve lash.

Mine was done By JHH engineering in brisbane. Well worth the effort and not overly expensive.

It can be done, I've had it done to mine. It entails losing the vct and some custom valve length work to set valve lash.

Mine was done By JHH engineering in brisbane. Well worth the effort and not overly expensive.

I was hoping to just swop cams without doing valve work or taking the head off. Not using vvt. Wont the hydr lifters compensate for the extra lift ?

guilt-toy is 370rwkw stock cams

i made the same power, stock cams

do you really need to upgrade?

awesome helpful info there again ash! ;)

no it wont work, u can try but u'll do more damage than good. its a head off job as like fineline said u need to convert it to solids.

I have been talking to Greg (proengines) i think, on here and he is doing some work with fitting the 26 cams to the 25 head. As im looking to do the same with my 25/30

I have Tomei 256 inlet and 264 exhaust cams but want bigger so 26 cams are the plan

guilt-toy is 370rwkw stock cams

i made the same power, stock cams

do you really need to upgrade?

Ah yes but arent you guys running those fabled "30" bottom ends.

I heard they make a gazillionty horsepower with the cam tunnels empty. ;)

I spoke to a guy that said he has used RB26 cams in RB25 head with no mods, drop straight in. Just wanted to confirm if someone else has done it. I got a set of std RB26 cams free from a friend.

Since I dont use vvt in any case, that would not be a problem.

Cant see why there has to be any head or valve work done if the replacement cam has the same duration with about 0.8mm more lift.

Ah yes but arent you guys running those fabled "30" bottom ends.

I heard they make a gazillionty horsepower with the cam tunnels empty. ;)

Not i!

2.5ltr RB25, that was in 2005 i think, maybe 2006. I cant remember :)

MatLowth on the forums had a 25/30 with RB26 cams... they most certainly do not drop in.

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