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Rb25Det Camshafts, How Big Can You Go With Vct?

NYTSKY

By NYTSKY,
in Engines & Forced Induction

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NYTSKY Grand Master

NYTSKY

Posted
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Hi all,

Head will be off in the new year and im looking into bigger camshafts. After some searching it seems no one has gone bigger than the off the shelf items like Tomei and HKS.

I have spoken to Jim at Camtech and he "thinks" a 268deg 9.15mm IN will work but will be down to the tuner to get it to work properly.

Has anyone tried a custom grind and gone bigger while retaining VCT? What are the hurdles involved in getting everything to work?

CHEERS

Dale FZ1 Veteran

Dale FZ1

Posted
Posted

I have spoken to Jim at Camtech and he "thinks" a 268deg 9.15mm IN will work but will be down to the tuner to get it to work properly.

Has anyone tried a custom grind and gone bigger while retaining VCT? What are the hurdles involved in getting everything to work?

You'd need to have things measured up, making sure piston-valve clearances are ok as the cam gets advanced/retarded Also possibly clearancing the head casting to get the cams to fit without fouling. Thirdly sufficient room in your valve springs to keep away from coil bind.

Interesting path to go down, and hopefully it works well. You'd nearly have to ask what it is you're setting out to achieve/retain, and whether VCT will help you do that.

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