How thick are the cylinder walls on the 2GR-FSE? I'm not finding a lot of details on the internals, other than the rods are forged, but the crank is cast. Couldn't find much info on the pistons.

Cast crank? Who's telling that lie? Toyota forges all their cranks and nitrides them for durability.

The cylinder liners are cast iron and they're cast into the block. They're thin in keeping with current fashion for weight reduction (sad but true, all the work they do to reduce engine weight gets sucked up by supplemental restraint systems and additional structures to support SRS.)

Get a TIS account. Check out the new car features for the 2006 IS350. You'll see a pretty complete analysis of the 2GR-FSE.

Cool - I was just googling around, not doing any real deep investigation. Couldn't find a lot of info on the engine though.

So when we want the is-f to be faster, you going to tell everyone to get a faster car? and after that car, another faster one?

Why don't you just tell everyone to buy a Buggati so we can forget about the upgrades.

Did you notice the at twice the cost part? I'm all about performance that can be had for a reasonable amount, but when you're spending exorbitant amounts of money to get performance that could be had through a cheaper means, e.g. buying a different trim level of car, you're approaching foolhardiness.

I understand the whole "work with what you've got" mentality towards performance, but when your only option is one that exceeds the cost of a better trim model, what was the point to begin with?

If I honestly spared no expense and wanted my MKIV to hand several hundred thousand dollar-priced exotics their ***, I'd need to invest ~$15-$20K. That would set me up nice - I'm thinking 70+mm single, fuel system (ethanol would be a good option for over 700rwhp), maybe a new bottom end just for kicks, and all the supporting mods, tune, etc. That's buying pretty high-end parts. In the end I've got a car I bought for $20K + let's just call it another round $20K.

You can't say that for the IS250. There's no option out there that makes meaningful power while keeping costs relative and sane for the pursuit of it.

I wholeheartedly agree with this. The ISx50 is not going to accept mods as readily and affordably as, say, a Civic or an SRT4. There is practically no market for it.

a friend of mine has a supercharged IS350.. but not turbo hah

It sounds like there are two camps in this discussion. The first one enjoys adding modifications and pushing the envelope with the 2IS. Why? Because it's fun and adds a touch of uniqueness to our vehicles. The second says "Why bother if it's not a 2JZ?".

To the second group - we hear you loud & clear. But you're obviously on a different page then the rest of us, and your arguments are getting tedious.

I think the entire point is that you can reliably mod the 2JZ as there is a lot of aftermarket support for it and go-fast parts are plentiful and cheap. As I said in another thread, the same can't really be said for the engine in the ISx50 and the IS F. Parts are expensive and so are the mods. A twin-turbo kit for the IS F goes for about $15k USD, and that's not installed, no tuning. A simple header costs in upwards of $1500, and installation can cost almost $1000. I reckon that for $17k you can have a 700hp 2JZ, and the car it's in will have cost less to boot.

Just my .02 cents.

I think the $15k for the IS-F TT kit from turbochargers.com covered the install and the so-called "tune". However, this doesn't make it any better b/c they have had many problems with it. (If you want to know what I'm talking about, go here: http://www.lexusf.com/forums/showthread.php?t=1934. However, that was before the company turned a new leaf. Right now, I don't know how the kits are fairing, but if it were me, I wouldn't be too eager to jump into anything.)

Don't get me wrong. I'd love to have some more aftermarket parts for the ISX50's, but the feasibility of building a high hp street monster is out of the question for the near future. I'm not saying that we can't squeeze in an extra 50+ hp though.
I for one, support the efforts of PPE Engineering w/ their headers, Fox and Khanvict w/ the S/C kit that he just installed, and of course Joe Z for the great and high quality parts for the 2IS's. Great work guys!

Totally see where you're coming from, but I didn't buy my IS350 with the illusion that there would be any real, credible, big power companies jumping onboard to R&D some serious advanced performance solutions for the platform. The most you can hope for is lesser known, individual-focused groups on smaller budgets to make parts for the car. Titan, SP, PHR, BL... those guys will never be on board. Just check the S/C thread to see what I'm talking about.

Why are people comparing the M3 to the 350 when they should be comparing it to the F....

and also its funny to have a 250 with +60 hp cause when you blow the other guy away thinking your a 250( sometime the 17k is worth it to some people seeing that guys facial expression)...just my 02 cents..if someone wants to spend their money that way who are we to say dont do that.

To quote Chris Rock:

You can drive a car with your feet too, that doesn't mean it's a good idea.

E46 M3, not the new one. He's talking forced induction on a 6 cylinder. 3.5L / 3.2L, 306hp/333hp, same torque, 13 second capable, roughly the same around a track... am I missing anything?
So you're seriously telling me you'd be $17,000 happier to own, I dunno, let's give you a lot of credit and say a high 12-second car, when you could've spent the same money on a more capable platform?