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Adjustable Cam Gears On S2 R33 Problem?

ps13_jason
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ps13_jason Explorer

ps13_jason

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hey hows it goin, last night was fitting cam gears to s2 rb25det engine and when i went to put the intake cam gear on it wouldnt line up?

it has vvt but i was getting rid of that and run adjustable cam gears.

the cam gears are JJR and they are identical intake and exhaust.

i have spoken to them and they suggested jump on the forums to get some ideas from other people.

anyone fitted adjustable cam gears to s2 r33 with success?

thanks

jason

Moodles2 Grand Master

Moodles2

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Posted

It should really just slip back onto the belt nicely. If the cam gear teeth don't line up with the belt, but try adjusting the gear either advanced or retarded until it slips back, this isn't ideal as you'll have to remember that position is actually neutral (I think thats how it works anyway).

skylinecouple Experienced

skylinecouple

Posted
Posted (edited)

Hey hold on for a second, don't get rid of your VCT, I think you'll find you will lose some bottom end. OOPS, sorry, just saw previous post by Nismoid. Every tuner I have spoken to recommends keeping it.

Edited by skylinecouple
PM-R33 Grand Master

PM-R33

Posted
Posted (edited)

I was under the impression you couldn't run an adjustable cam gear on the stock VCT cam from a RB25. You needed either an RB20 cam or an aftermarket cam which isn't made for VCT.

The VCT cam has a bolt that runs through the middle of it, non VCT cams have four bolts on the outside.

Edited by PM-R33
The Dan Grand Master

The Dan

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Posted
I was under the impression you couldn't run an adjustable cam gear on the stock VCT cam from a RB25. You needed either an RB20 cam or an aftermarket cam which isn't made for VCT.

The VCT cam has a bolt that runs through the middle of it, non VCT cams have four bolts on the outside.

+1

RB25 intake cam does not accept the same gear as the exhaust. Locating pin is smaller also

ps13_jason Explorer

ps13_jason

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yeh the pin is smaller and has one bolt through the middle...

hmmm well my option is different cam or stay vct?

so should vct timing be difficult to tune with an adaptronic ecu?

thought there would be few ppl with adjustable cam gears but obviously not until aftermarket cams?

dont think i want cams yet...

hmmm decisions...

thanks for feedback!

The Dan Grand Master

The Dan

Posted
Posted
yeh the pin is smaller and has one bolt through the middle...

hmmm well my option is different cam or stay vct?

so should vct timing be difficult to tune with an adaptronic ecu?

thought there would be few ppl with adjustable cam gears but obviously not until aftermarket cams?

dont think i want cams yet...

hmmm decisions...

thanks for feedback!

Yes, the adaptronic can run the VCT and it can be tuned to turn on at any time. Just use one of the Auxilary Outputs and switch it to RPM based. Have it trigger the VCT at whatever RPM you want. Normal is 1500-4500.

You can put just the exhaust cam gear on if you like. You will notice gains from increasing the lobe separation by a couple of degrees anyway.

Guilt-Toy Grand Master

Guilt-Toy

Posted
Posted

VCT is off at idle, you need to set the ecu to turn VCT on at about 1300rpm then switch it off again after the engine reaches 3000 - 5000rpm (depends on engine configuration) & switch it off when the engine reach's a certain boost pressure - every car is different and its up to your tuner to decide the switch on and off points for VCT when tuning.

if you set VCT up correctly you can tell the difference.

STATUS Grand Master

STATUS

Posted
Posted
VCT is off at idle, you need to set the ecu to turn VCT on at about 1300rpm then switch it off again after the engine reaches 3000 - 5000rpm (depends on engine configuration) & switch it off when the engine reach's a certain boost pressure - every car is different and its up to your tuner to decide the switch on and off points for VCT when tuning.

if you set VCT up correctly you can tell the difference.

yup with stock cams on @1250 and off @4700rpm

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