TOPENDMS

I came across two Japan based companies offering a bored throttle body service with a titanium valve flap. Was about $1000 but could probably also be done locally.

Haven’t seen any discussions in it..





2GR engine (3.5L) IS3.5L GSE3 # for

titanium butterfly processing more response up!

It becomes high response specification than the usual BIG throttle.

Genuine throttle It is a dedicated product for trade-in.

mikellucci

iTrader: (56)

Very interesting! It’s great to see the 2gr living up to its potential with companies now on board with support. I remember circa 2010 people thought we were crazy to supercharge the IS350 with no tuning

DickH

I have a machined throttle body on my 2is. It didn't make much of a difference but didn't cost too much either. I sent one out to maxbore and it was something like 140 to have machined. If you do this, request 72mm as that is as big as you can get with the stock intake.

DickH

I can measure it when I get home, I think it's something like 67-68mm. My car was able to adjust just fine with the 72mm throttle body. It took a couple minutes for the idle to relearn and within 15 minutes of driving everything was good.

Update

I can't find my spare throttle body at this time, but I am pretty sure it was ~68mm. I also have a 76mm throttle body, but I will confirm that my ecu was not able to correct itself to idle and drive fine. I am considering sending my spare throttle body out to get machined to 74mm to see if that is still within what the car can learn. I have found that 74mm is about as far as you can open up the stock intake and I am curious what it will do. I am not sure I would feel good about recommending a larger throttle body, peak airflow was something like 2 grams/sec higher at best going from stock to 72mm.

TOPENDMS

The throttle bore may be different for The IS2. Looks like the IS350 is also larger than the IS250

DickH

Found my spare throttle body and the inside diameter measures 69.9mm. I have a 76mm throttle body from a Nissan titan which is outsourced from the same company that I was hoping to make work. It appears that some older Maxima owners had gains swapping out their 70mm throttle body with the 75mm throttle body from newer models. I am curious if an ecu adjustment would fix the issues and allow me to run the larger throttle body. Also something to keep in mind is that our throttle bodies do not open all the way. If there were gains from a larger throttle body, we might see something from adjusting the ecu to open the stock throttle body further.

cliffhokie

Interesting find. With some previous cars/platforms of mine, opening up the intake side on NA cars (intake, TB, upper/lower manifolds, etc.) was commonplace to complement the headers/catback combo and tune, but I haven't seen too many NA applications with the 3IS.

DickH

There isn't much to open with the 2gr-fse intake, however the alignment/seams for the spare upper I bought were off enough to justify the time to sand/blend them together. I personally think the oem manifold wasn't made with performance in mind and that we could see quite a gain if we had the hood clearance for a proper intake designed for the extra revs we get from a tune. The is350 would be an entertaining DD if cams/springs and an intake were options.

TOPENDMS

69.9mm is a Lexus IS2?

DickH

Well I suppose we should just call it 70mm, but it's not quite 70mm at the butterfly.

NickCaesar

Have you seen this?
https://www.monkeywrenchracing.com/p...-engine-parts/

https://www.monkeywrenchracing.com/p...-valvesprings/

cliffhokie

Interesting, wonder what the approximate gains are. love the sound of a car with aggressive cams, but from my limited experience, costs vs gains, most people usually go FI, although our only FI option is pretty expensive. Also, depending on how aggressive they are, DD driveability is sometimes an issue.

DickH

I have seen those cams, however they are for a 2gr-fe, not fse. I might have misread, but I believe those won't work due to the fuel pump for our direct injection being mechanical and driven by one of the cams. I would also prefer not to use reground came to avoid the a shimming and whatnot required to fix the geometry.