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This topic has probably been discussed numerous times but I'm interested to know what people are dialling in their adjustable cam gears at, and with a brief outline on the running gear supporting their dial-in figures.

Also if you have before & after dyno runs with & without the adjustable cam gears.

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yeah thanks for that guys.

I probably didn't come across clear enough though......I'm wondering whether you guys played with both gears or just the exhaust (which many of you do), whether you are retarding or advancing the gears and by how much.

I know SK in NSW tends to retard the exhaust gear only, by about 4 degrees (which is 2 marks on the gears) as a starting point and I was wondering if that is the norm for the rest of you.

This isn't with a GTR it's with my CA but we gained 15kw more throughout the rev range and 5kw more in the top end by playing with the cam timing. We were looking for more midrange but we could have gone the other way and looked for more top end but being a 1.8 litre it better off with the extra in the midrange and it made the car sooooo much more drivable with the bigger turbo.

I have the graphs if you want to look at them?

Edited by D_Stirls

Pete, as i said previously, ive fitted cam gears to a mates 26 previously, widened the torque ban quite surprisingly....obviously its wise to fit your N1 water pump and new timing belt at the same time, so if you want a hand or any help dont hesitate Pete. Ill try searchin through the dyno PC tomorrow and find the before and after runs.

Edited by Ryanrb25

CamAdjustmentsCA18detGT2871RTorqueM.jpg

CamAdjustmentsCA18detGT2871RBoostM.jpg

The red line is the base line.

The dark blue line is with inlet cam 5 degrees retarded, which basically gives it the same spec's as a CA18DE exhaust cam

And the light blue line is with the previous inlet adjustment with the addition of the exhaust cam being 2 degrees advanced.

The timing timing above is cam degree's so times by 2 to get crank degrees.

These are the Gears, this is when i was trial fitting them hence some of the bolts aren't fitted.

Image600.jpg

Edited by D_Stirls

Thanks for the info guys, that's great......Ryan, I'll be sending you a PM shortly.

Dale, that's exactly the info I've been looking for.

I'ts clear on the graphs that even though you're not gaining a huge amount of power, you are definitely making it earlier, particularly between 100 to 160 kph (in top gear I assume).

The more I've been looking into it for 26DETT's (can't really comment on others), the more I feel that adj gears will make more of difference on the street than cams and definitely more useable power.

I realize there are other engines out there that work better with cams on the street but even Martin Donan agrees (after a lot of testing on the dyno) that the $1000 for a couple of kw just isn't worth it.

yea in alot of instances (not all of them) cam's aren't worth the money for a streeter...

My mate lashed out 1600 bux for the Jun cam's which apparently are one of the best and to be honest it would have made very simular power with the stock rb20 cam's which are pretty good already. However im sure on a 600kw rb26 they would make a world of difference.

yeah spot on Ryan, even Shaun from Boostworx will tell you that 1 psi more boost can in some cases do what cams can do and its free.

As you say, for a big HP ie. drag car (which I'd love to build), cams are a must.

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