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Cam Gear Results... NOt Good :(

The Mafia

By The Mafia,
in Engines & Forced Induction

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The Mafia Grand Master

The Mafia

Posted
Posted

I have just had a HKS Adjustable Exhaust cam gear fitted to my R33 Series II GTS-T 96 model.

ITs got a powerfc, full exhaust and split dump, pod filter, 11psi, and 10% mix of toluene.

My mechanic, very respected, (just got 300rwkw out of a VL turbo that day for an example just tuning it) put the cam gear in, and set it to 1,2,3,4 degrees retard, and 2,3,4 degrees advance, and every position the car lost power,

The only position the car made good power was at 0 degrees.

Anyone seen this before? I thought 4 degrees retard was supposed to make more power in the bottom end?

:)

He's tuning the power FC and has managed to push it from 160rwkw to 180 so far, and like 2 hours

He says there is more to go yet

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Sydneykid Grand Master

Sydneykid

Posted
Posted
I have just had a HKS Adjustable Exhaust cam gear fitted to my R33 Series II GTS-T 96 model.

ITs got a powerfc, full exhaust and split dump, pod filter, 11psi, and 10% mix of toluene.

My mechanic, very respected, (just got  300rwkw out of a VL turbo that day for an example just tuning it) put the cam gear in, and set it to 1,2,3,4 degrees retard, and 2,3,4 degrees advance, and every position the car lost power,

The only position the car made good power was at 0 degrees.

Anyone seen this before? I thought 4 degrees retard was supposed to make more power in the bottom end?

:(

He's tuning the power FC and has managed to push it from 160rwkw to 180 so far, and like 2 hours

He says there is more to go yet

I agree with Bass, I know it is obvious but you never know. The CAS is connected to the camshaft itself, not the camshaftpulley. It looks like the CAS is connected to the pulley but it's not. I have seen very experienced mechanics make this mistake. If you retard the camshaft 4 degrees, you retard the ignition timing 4 degrees. So everytime you adjust the cam timing you have to reset the igntion timing with a timing light.

If you have been watching and he hasn't used a timing light to check the ignition timing then that's your problem. :spcartman

Hope that is of some help.

Trust33 Grand Master

Trust33

Posted
Posted

so why does it work for some and not for others?I personally think there are gains to be had.I have never done it b4 only heard mixed emotions on it more postitive than negative.

Personally i think that there are gains to be had and if you go to someone or are that someone who knows what they are doing when it comes to this kind of tune they could prove it also.

Not to much longer b4 my theory is put into practice on my car.

predator Grand Master

predator

Posted
Posted

seems like latter model s2 r33 and R34 seem to get less gains than the others.. few people have xperienced this in the past. Could be something to do with the slightly different VVT setup in the newer cars.

But there are plenty of older threads on it.

The Mafia Grand Master

The Mafia

Posted
  • Author
Posted

I am going to start another thread about it, but he left the cam gear at 0 degrees and went and tuned the powerFC.

Here are the results.

Sydneykid, I appreciate your input, and will most certainly let him know. He is a very very experienced mechanic, but hey, not everyone can know everything. I am sure he will love the information, and most certainly try it.

I love the world of free knowledge.

pcy.JPG

The Mafia Grand Master

The Mafia

Posted
  • Author
Posted

ok, I spoke to my mechanic thismorning, and he said that whenever he adjusted the cam gear, he reset the Base timing with a timing light, this guy is pretty on the ball even though he hasn't really done a cam gear before on a skyline. He didn't really know what to expect.

Maybe the Series II's have differenty VVT or something, and the power is already tehre, and just needs a PFC to tap into it?

He said it was very easy to get that power, but didn't want to go too much further because he didn't want to risk detonation.

I reckon thats awesome power for only 10.5 - 11psi, and its so smooth, doesn't hit hard, its like got heaps of torque from the word go.

Pull the hardest at about 5k though.

Awesome to drive now.

Bass Junky Grand Master

Bass Junky

Posted
Posted

On my R34 they did buff fu(k nothing.

Cost me $600 in workshop and dyno time (At Hypertech) to find this out for all of you.

Check out this thread.

http://www.skylinesaustralia.com/forums/sh...light=Cam+Gears

wolverine Grand Master

wolverine

Posted
Posted
Can anyone confirm that cam gears don't work on late model RB25's?

I was looking at fitting one to my S2

mine came back yesterday (R33 S2) and cam gear picked up extra kW most of the way thru with around 15kW at the top end. they work fine.

GIGOLO Rising Star

GIGOLO

Posted
Posted
mine came back yesterday (R33 S2) and cam gear picked up extra kW most of the way thru with around 15kW at the top end.  they work fine.

Thats a really good result, a couple of questions though.......

What cam gear did you get installed?

where did you get it installed and tuned?

You only need the exhaust cam gear right?

Cheers

lukevl Collaborator

lukevl

Posted
Posted

Don't murder me but I'm pretty sure as the Rbs got newer, Nissan closed the lobe centres up. The early models ran very wide separation angles (Just like the VL turbo) but with newer models they closed them up gradually and increased overlap.

By what you guys are saying the gains are had by retarding the exhaust cam- is this right? If so then you are doing what nissan did with the later model hence less power increase because they have already moved them to a lesser extent.

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