Rb25de Cams

[Dahtone Racing]

what are the lumpiest cams i can fit in an RB25DE head with out machining shit

also will RB20DET ones fit????

btw the head is on a RB30 bottom end

thanks

anf

[Bl4cK32]

rb20det ones will fit

lumpiest is the usual 9.0mm lift

[SECURITY]

arent the n/a cams 'harsher' than turbo cams?

im not 100% but i was told n/a cams onto a turbo head would be more beneficial. not the other way around.

someone please correct me if im wrong.

or are you just trying to figure out which ones will fit?

[Stronzo]

r33 rb25de/det camshafts are the same. from 0997 exhaust shaft changed for new cas, but it`s still the same for de and det.

[Cubes]

Typically when people say N/a cams are more agressive it means they run more overlap/lump/lope etc.

Turbo's due to their high back pressure benifit at high rpm by running cams with little overlap.

The r33's vct system. On idle there is next to no overlap, just off idle vct enables and adjusts the inlet cam so there's some healthy overlap. Overlap helps mid range and spools the turbo quicker. As high rpm approaches where exhaust manifold/scroll pressurs begins to rise the vct again disables to reduce overlap.

From memory rb20det cams are 240duration 7.8mm lift on both the inlet and exh and have been setup with next to no overlap.

The R32 rb25de runs a 240duration 7.8mm lift on the inlet and a 232 7.3mm lift on the exhaust. The rb25de cams run more overlap; exactly what I forget.

[Dahtone Racing]

its an R32 RB25DE head

i forgot to mention that

[mr_rbman]

i had rb26 cams reground to this spec: (For my r32 rb25de head)

not installed yet so i cant give any results.

[Cubes]

Nice..

254duration in/exh

8.5mm in/exh

Should also be around 25degree's overlap which is quite a bit. Help that big 1.06 spool.

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When are you planning on getting them fitted?

[Dahtone Racing]

so 9 mm lift should be able to go straight in????

[mr_rbman]

Nice..

254duration in/exh

8.5mm in/exh

Should also be around 25degree's overlap which is quite a bit. Help that big 1.06 spool.

----

When are you planning on getting them fitted?

when i do my valve springs, hopefully not too much longer, just got to get andrew to post down his tools he has to change valve springs!

[mr_rbman]

so 9 mm lift should be able to go straight in????

thats about your max without modifying your valve train etc.

[Dahtone Racing]

thanks fellas

[Dahtone Racing]

ok found some 264s with 9mm lift

just a final triple check that these will be ok????

[Cubes]

With a duration as such you'll be looking power holding well to 7500-8000rpm providing it has a decent plenum and exh. manifold hanging off it.

[Dahtone Racing]

awesome I've got a custom plenum and custom high mount exhaust manifold on this motor.

so we'll see how they go

thanks cubes