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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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Big cams improve power at higher RPM. To take advantage of big cams, you'll need to rev the engine a lot higher.

I'm not a 2J specialist so I don't have any 2J-specific experience to share with you, but I'm guessing those cams with 230* or more of duration @ 0.050" will make peak torque at 6000rpm or more...

...probably not what you want for anything less than an all-out build.
 

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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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whenever i see post about NA builds i think of this: Naturally-Aspirated 2JZ-GE '95 Toyota Supra with ITB's all that work and money for 260Hp.
I was reminded of that article as well. Thanks for providing the link so I could review it; it's been a couple years.

I know 260whp isn't an amazing number these days, but it's still 87hp per liter - at the wheels. Probably 100bhp per liter, or very close to it. That is pretty legit. A really well-tuned 6.2L LS3 with all the goodies will usually come in around 475whp - which is only 77whp/L or about 88bhp/L - and that's with a LOT of cam timing coupled with fabulous cylinder heads and intake manifold...

Also, who knows how well-matched the header, ITB intake and valve events match eachother? You can usually get ~110-115bhp/liter at or below 9000rpm with a nicely matched head/cam/intake/header setup.
 

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Is a waste to not turbo a 2jz- they are very heavy and tall and long. A bone stock iron block 4.8 lt motor will outperform a built to the hilt n
2j in any racing discipline or on the street. Only reason to build one is they are stout enough for lots of boost. Just bolt discarded factory turbo parts on to it , that will outperform the gnarliest NA 2j, unless your just building a built bottom end and ported head for a planned turbo setup your wasting a 2j but I’m just a Moron on the Internet
 

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I hate to take the wind out of your sails, but according to Headgames, it's rare to even need 272 cams unless you're making well above 1000 horsepower and need more RPM, I'd say 8000 is low for them. It will sound cool, but these motors respond very poorly to NA mods. I was thinking about doing a 1st gen "ISF" build with a 3UZ though.
 

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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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What are you after with this project? Daily driver? Fun fair -weather toy? Track days? Something else?

My original plan was to drop an LS3 into a nice IS, and make it near-OEM. In my search for a nice IS, I came across a good deal on one already turboed.

It's a fun toy and I definitely enjoy playing with it, but every time I drive it, I long for the extra 200lb-ft of torque (at 3000rpm) and 200lb weight reduction (on front end) the LS3 was gonna provide... 2Js are heavy and 3.0L is not alot of engine to propel them smartly. Obviously boost helps; but not below ~3500rpm.

Just something to consider.

Also: it's easy to underestimate the time and cost associated with turbocharging; there are lots of "a few hundred here and a few hundred theres" that quickly add up to several thousand.
 

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I hate to take the wind out of your sails, but according to Headgames, it's rare to even need 272 cams unless you're making well above 1000 horsepower and need more RPM, I'd say 8000 is low for them. It will sound cool, but these motors respond very poorly to NA mods. I was thinking about doing a 1st gen "ISF" build with a 3UZ though.
GSC provided some dyno charts of the s1 versus s2 over at supra forum. Even they showed little to no gain at 8000rpm between the two but a lot of low rpm HP loss with the s2. The s1 is slightly more aggressive than the 264 and the s2 is more aggressive than the 272 for reference.

NA engines are cool but with only 3 liters to work with…

It’s hard to make more power on the IS300 cheaply no matter which route you go but doing the work yourself with help a lot.
 

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If you must, you need custom ground cams, as all of the aftermarket cams are ground with almost no overlap, like all turbo cams. If your trying to make big NA power you need a bunch of poor idle 3 stroking stumbly loose converter ass overlap, and I have a 2jz ge vvti stainless long tube header for sale, for 200 bucks
 

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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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I'd say I'm after a fair-weather sort of driver, hopefully lots of track days.
Sounds like fun! I'd get your chassis all squared away before going after more power.

I like the IS300 platfom, but have always found it feels a bit too heavy. That, combined with what "they" say about the 3SGE-powered Altezza always makes me yearn for a several hundred pound weight reduction. My turbo IS definitely feels like a heavier car than my stock daily driver IS; despite the turbo car having about 300 more rwhp.

Keep us apprised with your project!

Last: If you have an OEM header with cats that passes Cali smog - there is a pretty decent market around here for them. These cars are getting old, catalysts are wearing out and replacements are $$$
 
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