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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?

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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. :dry:

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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. :laugh:

----

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!

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