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Basically all the circuit GTR's here under 400rwkw are using stock cams and cam gears these days from what ive seen.

Might be the odd one here or there that doesnt, but most are im told :huh:

Spend the coin elsewhere ;)

Interesting. can't see why you wouldn't go upgraded cams.

You can lay the smack down on standard cams with the tomei 260's on even stock GTR turbo's. between stockers power and 400rwkw without question , there is plenty of benifit to be had. This includes making more power than standard cams even at lower rpm ranges.

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Speaking to Snowman who has 2860-5's, he found just fitting cam gears made the biggest difference, so i'd at least look at those... the actual cams weren't that beneficial, if anything causing less down low, and hence took them out, but definitely left the adjustable cam gears fitted. The tuner really needs to know what they're doing though :huh:

Anyway, I ended up fitting Tomei 260/260 9.15mm lift cams + cam gears (no head mods required, all shims were fine).... gained 38kw@4 on the same boost, using 2860-5s... with more power throughout the midrange, but significantly more high in the rev range. Fine for my driving style, I don't need brilliant response as I don't do any competitive circuit work ;)

Edited by TommO
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Well some of these cars actually had the Poncams in there too and pulled em out in favour of the stockers :huh:

Possibly there is something someone found with some development i suspect

Perhaps altering things like the head through porting/ combustion chamber and compression you can wind up needing different specs for optimum results but, I you'd still get more our of a set of upgraded cams designed around the motors characteristics with more lift at any point where positive boost is being built. The fact is we are stuck with off the shelf cams meaning we get to pick sometimes from a bunch of 'wrong cams' (including stockers) and just get the closest fit from what we have to choose from vs a purpose designed set for our specific motor setup and application. I'm guilty of buying like this and a case in point is when the cams are better than what you have and the price is cheaper than the set thats really better.

Setting up cams properly is something thats always been in the minority across the tuning world, whether you talk NA or V8 or turbo. The people who actually make cams (experts) seldom are consulted by mechanics installing them leading to alot of poor reputation and crap talk on the street 'brand x is so much better than brand y always...'. The skyline tuning community at large seems to suffer the same issue where people seem to be suprised when cams do or don't work as if it's been caused by some sort of magic.

After I had various 'magic' convinced people tell me I was going to waste money and recieve less performance, as I had already calculated I've managed to pull more down low power out of Tomei 260's on small stock turbos than people can get from stock cams and adjustable wheels. I have no doubt I can replicate the same feat with any turbo of larger size. The only area the stock cams are going to be better is in emissions and the NA part of the power band.

Based on the theory of how cams work, thats what you naturally expect. I'm certainly no expert so that's why on the odd occasion I think of cams as an upgrade I try to get in touch with info from the people who make them to determine what I need to do.

I'm going the Tomei 260/256 this time round for the GT-SS turbo's later on, will be tuned for 300rwkw or less to be kind to the old stock engine but, I'll be shooting for lots of low/mid power. I'll be taking the pepsi challenge again to show how povo the stock cams are 'again' when properly timed and tuned.

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I'll have stock cams with my GT-SS setup, so we can kinda compare when i get around to finishing the car off (2-3 months)

I'll note my tune settings for the cam timing this time round so once I show you how much cams slap the stock ones you can go ahead and buy with confidence and also have a pretty good starting point for optimum settings. :(

What other mods will you have on yours?

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  • 3 weeks later...

I am really curious about this too..... I WAS going to put a set of tomei 260 / 9.15's in an RB26 I have apart at the moment BUT I hear from some people "waste of time" and others say "got me 40 more KW on the same boost..." (I am running -7's for what its worth)

Allegedley the cams are supposed to be good for midrange - with little loss down low if any?

Would love to here some genuine back to back reports - on low dow power and impovement in midrange (if any) not just on the dyno, but on the tarmac... do they FEEL and better or have any real world measurable benefits?

Who has an (other) opinion?

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I'll note my tune settings for the cam timing this time round so once I show you how much cams slap the stock ones you can go ahead and buy with confidence and also have a pretty good starting point for optimum settings. :)

What other mods will you have on yours?

Nothing :)

Just a build bottom end, GT-SS and the other common bolt-ons, cam gears, injectors usual.

Wont be till April now as im off too Thailand shortly so cash spending = car on holding :P

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Nothing :P

Wont be till April now as im off too Thailand shortly so cash spending = car on holding :)

Dammit, come on Ash, get that thing on the road! - Thailand holidays are nothing but memories and crotch itch afterwards, Skylines are for eva haha.

Edited by GeeTR
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