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hi guys,

i am looking at upgrading my cams but i want to know how far i can go with the rb26 head before i need to change buckets & springs...

as far as i am aware tomei pon cams @ IN 260/EX 260 Lift 9.15 is close to the max?

fyi im building an rb30 & my goal is 400+awkw (street setup)

regards,

marko

9.15mm lift. ANy more and you have to machine the head

So:

Tomei Poncam

HKS Step 1

A'PEXi Sttep 1

GReddy Step 1

You can get different durations from every manufacturer, but the lift will all be around 9.1 to 9.15mm

should i look at matching my exhaust cam with my inlet cam taking into consideration the below specs:

A269IN (inlet) 9.15mm lift

A252X (exhuast) 9.15mm lift

...or can the 252degree be adjusted out with the cam gears - NFI

i just went and bought

tomei 270 11.8mm and tomei buckets.. obviously needs work for cam lobe clearance and buckets replaced.

i thought since the bottom end will be pretty soild, the top end deserves a bit of a tickle too..

i'll prob have a set of hks or tomei cams for sale that will suit standard buckets. will get them measured up when i pull em out.

lol, with nearly 12mm lift you will be highly likely to end up with valve meeting piston and any decent rpm... it will certainly need checking and most likely new pistons.

lol, with nearly 12mm lift you will be highly likely to end up with valve meeting piston and any decent rpm... it will certainly need checking and most likely new pistons.

not exactly...there is a way to keep everything friendly. Its doesn't involve pistons either.

Edited by DiRTgarage

yeah of course there are ways to stop it happening, but they only work if you do it before your engine is built. ie it needs to be checked while everything is in the build.

i'm sure my engine builder will not have a problem at all.

nothing has been built yet... slowest build ever perhaps?

then you have nothing to worry about. :(

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