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Discussion Starter · #1 ·
Hi all. I've been looking at camshafts for an NA build. I see BC offers a "stage 3+" profile, 276° duration, 10.29mm lift. I'm curious if anyone has experience with this aggressive profile, and concerns about retaining VVT-i. I also wonder if such a dramatic profile would provide any real gains over say the 272° (~9.5mm lift) "stage 3" profile. Maybe in the future I would want to throw a turbo at the setup, but for now I hope to eek as much gain as I can out of an NA setup, modifying the intake and exhaust and working the head.

What do you think? Where should I spend my money? I think I'd go forced induction before thinking about boring a block and aftermarket internals, if that sways your thinking.
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Discussion Starter · #3 ·
That concern is what I've been noodling about as well. I've got some interesting ideas about it, including Atkinson (dynamic Otto) and retarding VVT-i a tooth or so (compensating/controlling via ECM).

It'd be great to take it to 8k RPM; I think that's doable on stock bottom end w/ springs and other head work.

What I'm trying to decide is which profile to drop the dough into ... $1k is a lot of money for cams, but that seems to be the market these days and I don't imagine much gain without a cam. 264° (220/226) just doesn't seem worth it, so toying between the 272° (229/230) and 276° (234/238).

I want to avoid FI as mentioned, but I imagine I'd step that direction before boring the block and oversized internals. I suppose nitrous is always an option, but I'm not well versed or know what's available or even lawful yet.
 

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Discussion Starter · #5 ·
Turbo charging a bone stock long block will be cheaper than what you are trying to do.
While that may be true, buying used parts and such, I'm not entirely convinced: there are added complexities with turbos both mechanical (exhaust, intake, intercooler, chassis modding, etc.) and management that I'd have to contend with. To be honest, cheap horsepower isn't really what I'm after here either: I hope to gain knowledge and experience from dealing with these kind of intricacies of building and tuning a motor, and while cost is of course somewhat of a concern, it's not my first. In this case, I'd rather avoid buying a set of (overpriced IMO) cams only to find that I should/could have gone with a different profile.

I do appreciate the input, so please keep it coming.
 

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Discussion Starter · #7 ·
😆 I like where your head is, but I've already got 6 2JZ blocks needing some attention. I have an LC9 in the pickup I can play LS games with, but I'm dead set on making something of these 2JZs.

The feedback I'm getting from most is that this aggressive profile isn't well suited for my intention, seemingly targeted at ultra-performance setups w/ turbskis looking for more oomph / options, like a drag setup. I think spending the $ I'd skip the 264° "mild" profile and put it toward the 272° "aggressive" profile, not thinking about FI. Of course, then, later targetting a "mild" FI build, 264° would likely be more desirable. Of course, most of the feedback is first like: "wait ... 2JZ w/ no boost?" ... yeah.
 

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Discussion Starter · #14 ·
Well, the whole point of my post is to realize there's no wind if so. I've been putting more thought into what FI plans look like now, to inform my decision. Most signs are pointing toward the "mild" profile all things considered, but I do want it to sound cool :). I think I've found a good cheap route for boost without having to build internals, and to get into that realm before thinking about more, checking some other boxes I have open too (a la fabrication). That route is significantly cheaper than say via new Garrett G30-900, probably even cheaper than purchasing two sets of cams, so that's great.
 

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Discussion Starter · #19 ·
Well at this point I'm entirely re-thinking where I'll put my money. I'm still rather set on upgrading cams, but realize now that avoiding boost is sort of foolish w/re: cost/power.

I'd say I'm after a fair-weather sort of driver, hopefully lots of track days. I see it progressing in stages though, but I have a lot at my disposal, but it all needs work to be worthy.

Re: NA overlap, I'm thinking that could be achieved by playing with the VVT-i and belt timing, which sounds like fun.

@Theneil300, header is in CA I assume? I have no stock manifold willing to ship you, but that header's kind of interesting though not for long if I plan to boost.
 

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Discussion Starter · #22 ·
That's kind of where my head is at now after thinking on it and all of the feedback more. FWIW, bushings and handling are all well under way, which is why my mind is on this subject. Poly differential bushings, mounting

re: handling, I have sets of Koni Yellow I'm waiting to determine what springs to pair and swap in until after some track time; have a new set of KYB (stock springs/setup) all around that has very low milage. Definitely want to get a feel for things before I swap them, hence the long term thinking.

I'm going to be building a block back to stock, and begin another on a run stand for head work and wrapping my head around the tuning stack for the engine management I've picked. I have lots of options, many blocks and another chassis at my disposal, along with a small selection of trans and diffs, which is both a win and a sort of bane w/re: choosing a path forward (in consideration of cost). AR-5 trans is most likely as I have all the swap bits ready.

Right now, w/re: FI plans, I'm eyeing BMW N54 turbo set to slap on, can be had rather cheaply and ought to fit without much fab, and put me in that realm (though likely wanting, and hopefully ready for, more).

I've been following your build too @_zaclemore; getting some good ideas from it. (y)

Again, thanks everyone for the help, giving me a lot to think about.
 
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