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Cam timing of Rb26

Mik

By Mik,
in Engines & Forced Induction

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Amaru Veteran

Amaru

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To save starting another thread, id also be interested to know, I have HKS GT2530's with stock camshafts and camgears. This week Tomei 260 in/ex camshafts are being put in and tomei cam gears. I have heard people say dont adjust the Tomei stuff as you wont get power, is this true? If not, whats the most common adjustment to bring boost on as early as possible and have nice low to mid range torque. :)

Sydneykid Grand Master

Sydneykid

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To save starting another thread, id also be interested to know, I have HKS GT2530's with stock camshafts and camgears. This week Tomei 260 in/ex camshafts are being put in and tomei cam gears. I have heard people say dont adjust the Tomei stuff as you wont get power, is this true? If not, whats the most common adjustment to bring boost on as early as possible and have nice low to mid range torque. :)

The Tomei Poncams 256/260 in GTST's haven't needed timing adjustments in my vast personal experience of 2 cars. But the Tomei's in GTR's ALWAYS need adjusting. As someone else posted, advanced 2 degrees on the inlet and retard 4 degrees on the exhaust is a good place to start. :burnout:

Mik Experienced

Mik

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The Tomei Poncams 256/260 in GTST's haven't needed timing adjustments in my vast personal experience of 2 cars.  But the Tomei's in GTR's ALWAYS need adjusting.  As someone else posted, advanced 2 degrees on the inlet and retard 4 degrees on the exhaust is a good place to start. :burnout:

SK, is +2 degrees IN and -4 degrees EX a good place to start for standard cams too?

Sydneykid Grand Master

Sydneykid

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SK, is +2 degrees IN and -4 degrees EX a good place to start for standard cams too?

I usually start at zero, that's REAL zero after allowing for cambelt stretch plus any head and block machining. But I always head towards advancing the inlet and retarding the exhaust first. :burnout:

Sydneykid Grand Master

Sydneykid

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Posted
Is that + 2 and - 4 actual crank degrees or notches on the cam pulleys ?

Thanks.

Depends on the brand of cam pulley. Easy to check, each tooth on the cam pulley is 15 degrees crankshaft. Just count the notches for one tooth. :wavey:

Sydneykid Grand Master

Sydneykid

Posted
Posted
SK , does this also work for the 26/30 single turbo RB30 . 

Thanks  A .

Are we talking camshaft timing? If so, the +2 inlet -4 exhaust is a place to start if you are running standard cams. I have seen some different timing work better with large duration cams. I have a pair of Jun 272/280's with 10.5 mm lift going in my new RB31DET, so I will be most interested in where the timing ends up for best average power using those. :cheers:

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