Jeff Lange

iTrader: (1)

No, you can use the stock differential without issue.

Jeff

almrlon

Thanks Jeff,

I've learned a lot about our cars here and especially reading your 350 swap post. I have an itch about flywheel when it's time to change my clutch which will be soon but not sure if its a good idea since I see all these post from guys that did it. What's you input on this?
Also, I wanna keep my IS250 but just want more power and still wanna daily it at around 270-290HP. If I was able to get the 350 engine even better but I don't wanna go through much hassle with wiring and what not so the 3gr-fse looks like a good option to go with but just wanna know what you and everyone else thinks about this and I'm sure many 250 owners feel the same way about the lack of power but wanna keep the reliability of Lexus. Thanks in advance...

Nixcision

iTrader: (3)

Considering this as well, as the aftermarket options available for the 3gr well surpass those of the 4gr that I have...

I have an 09 AWD. Is this swap still possible given my AWD system (and trans)? Anything extra needed to make it work if anyone has any ideas?

Edit: The GS300, where this engine can be found, was also available in AWD, so I'm assuming this shouldn't be that much different?

Jeff Lange

iTrader: (1)

What aftermarket options exist for the 3GR that don't exist for the 4GR? Just curious.

As far as the AWD goes, that should be unaffected. Even if you got a 3GR from a RWD car, the necessary parts from your existing engine can be swapped onto it to make an AWD 3GR.

Jeff

Nixcision

iTrader: (3)

Thanks Jeff!
I should also note that I have a Canadian 09 250 awd, and would likely source the motor from an older (06?) Gs300 AWD or RWD (swap parts)... if that changes anything.

It was to my understanding that there were more forced induction options available (TOMS, hks, etc.)? Also with a slightly lower compression ratio and higher baseline dyno numbers, I'd assumed that it would be more worthwhile to pursue stepping up power as opposed to the 4gr

Also: would it make sense to say that a 3gr swap into an awd 250 would be simpler than a 2gr swap (differences in injection, transmission, etc.)?

jrule2

Just FYI any force induction kit that is going to bolt onto a 3GR-FSE engine is going to bolt onto a 2GR or a 4GR. The compression ratio difference between the 3GR and 4GR is also pretty marginal.

Nixcision

iTrader: (3)

You're correct, I likely read the 3gr-fe specs when I meant to read the fse for compression ratio.
(10.5:1 vs 11.5:1 (fse)) But even so, a slightly lower compression could make room for slightly more boost -> slightly more output per cubic inch

Yeah HKS's kit is for the 2gr and is likely what I would use because I can get a good deal on it thru a local vendor in CAD.
After doing a bit more research, I have found that the 2gr has more differences (e.x. ported and d/i) than the 3gr and 4gr (which are quite similar - hence making this swap more reasonable than a 2gr swap)

The main point being that one can start at ~250hp at the crank as opposed to ~200hp (4gr).... these are by no means impressive numbers but if going fbo along with the hks supercharger with a 3gr can bring me to 250awhp, I'll be happy. My car is a low and slow cruiser so a little bit of extra punch and some cool noises would be nice (cost prohibitive? )

If the swap is supposedly "straightforward" then why not start ahead right?
With this optimism in mind, if I end up keeping this car for many years yet, this could be an upgrade down the road.

is350uk

The swap is very straightforward , it's like replacing your engine with another of the same kind, and you can use your existing electronics , no modifications or anything needed

Nixcision

iTrader: (3)

good to hear. Also wanted to see if anyone knows: are there any options for upgraded internals of any kind for the 3gr-fse? Theres basically nothing for the 4gr at this time.
little things go a long way....

is350uk

unfortunately there's only intake headers and exhaust , some superchargedkit floating around but expensive small gains

jrule2

I wonder how far ahead you'd actually end up with a supercharged 3GR versus a supercharged 4GR. My IS250 has one of the supercharger kits that a member (Stewart) had made. My car could handle more boost and I have run as high as 12psi but the car just doesn't have the fueling for it. I'm of the understanding that the 3GR uses the exact SAME direct injectors as the 4GR.. So you may actually run out of fuel at a lower psi with the 3GR. Plus the 4GR already makes more HP/litre than the 3GR-FSE.

is350uk

yeah true that's why some superchargedkit comes with extra injectors , I would like to know the size of the injectors on the 4gr-fse and would think of replacing them with the 2grfse ones if I was to go supercharger

Nixcision

iTrader: (3)

This is an interesting development.
My basic thinking was 3gr: 250hp + supercharger
vs. 4gr: 200hp + supercharger

So you'd think that the 3gr would put out higher numbers at the end of the day, even if boost is slightly lower...
2gr uses ported AND direct injection so its a bit of a different delivery system?

Jrule2, are you anywhere around 7psi currently?

IF I did this swap, I would likely supercharge with the motor already out of the car

PAVGR

iTrader: (2)

I have a 4GR supercharged and I m running 7psi of boost.The car is very fun to drive and the sound of the procharger is amazing!The think is I m sure the car is getting lean even with the meth kit I m running.I saw 13 at 6500rpm recently in a street race I had.The car is running great now with the cold weather here in Greece .I will take off my secondary cats tomorrow(I m on stock exchast because I hate noise in my car)and I ll try to make a video of my car.

Nixcision

iTrader: (3)

in for a video!

That is definitely a concern - leaning out .... if only there was a way to improve fuel delivery on the 4gr or 3gr