maj75

I am considering either an '09 IS-F or a leftover '08 GS460. Each car has +/_. Could some one explain the discrepancy between the LS460 HP rating and the GS460 rating? I thought the GS was the "sportier" model so why less HP? As far as I can tell the engines are dimensionally the same, is there any way to get the LS's 380 HP out of the GS with ECU programming? What parts need to get changed to give equilavent (or Better) HP in the GS?

EyeKutr

iTrader: (5)

hey maj
there was a discussion on this a while back, do a search and a couple fo threads will come up, lower HP has something to do with a single intake versus dual I think, or something along those lines...too much of a pain to try to gain the extra ponies..

maj75

I tried some searches but all I got was 10 pages of about the fact that the HP rating was lower and alot of about why the rating is lower.

I could find no practical information about what a GS460 owner could do to remedy the situation. If there is a post, please link, I will continue to search.

Stormforge

the fact that you are looking for more power suggests that the IS-F would be the better choice for you. you get a rocket straight out. upgrading a GS460 to get more power is doable, but you have 2 obstacles: 1) do any power mods, and you will void your warranty; 2) you are going to spend a lot of money to get it done.

the logical choice would be IS-F, you get the power you want and maintain your warranty.

LexFather

We did have a good discussion on this, Henry do you remember the thread?

After discussion, we assume it is b/c the LS has space under its hood for a true dual intake system (left and right) whereas the GS 460 only has one intake that looks very similar to the one on the GS 430.

Surely when the 4GS arrives, the car will be larger (sadly b/c every other car maker thinks bigger is better) and have space for the dual intakes to "unleash the fury".

I have a 450h and its faster. It doesn't sound nearly as good but its faster from a standstill and in passing power.

The IS-F is the most extreme Lexus ever built. It sounds wonderful WOT. It is by far and CLEARLY the fastest Lexus. I have driven the GS 460/450 and IS-F at the track. The IS-F is a COMPLETELY different animal, the GS's feel like Town Cars in comparison

The IS-F is a special model under the "F" marque so having more HP is not an issue with the brand. For instance the C63 has more power than a S550, E550 etc. M3 has more power than a 750, 650, 550 etc.

To be honest the GS 460 is fast enough. The IS-F really turns it up a notch 3 times.

Best of both worlds is a GS for the week, IS-F for weekends

Stormforge

you've taken your 450h to the track?!? please do tell about your experience! pls post link or start a new thread! thx!

maj75

Found the thread and added to it. Thanks for the tip, I searched GS460 and dual intake and found it. Performance discussion to continue on that thread.

As to the differences between the GS460 and IS-F, I have driven both. Before I go further, I have no wish to start a flame war. But I have issues with the IS-F. I am 52 years old and my current daily driver is a C6 Corvette with a 6 speed manual. (I don't need snot nose kids from the IS-F forum who get defensive about people who have their own opinions) Here are my impressions: for what the IS-F is, I would prefer the option to get a manual transmission, and I HATE the exhaust. If you love them both, good for you. I am not criticizing your choice and I don't need your post expressing your opinion in opposition. On the other hand, I have no issue with the auto trans being in the GS460. It is the trans I would chose in that car even if there was a manual option. I also like the styling better on the GS. I prefer the IS350 styling to the IS-F (heresy!).

I liked the firm ride of the IS-F, but do not find the GS too soft. I like the relatively greater space of the GS. I read alot about GS owners complaining about creaks and rattles, but seriously, if you have daily driven a C6 vette, you would not notice anything. I thought both were exceptionally quiet and refined, relative to the vette. I like the IS-F motor and the sounds it makes. If the cars had similar horsepower, I would chose the GS460 w/out hesitation. I know I can "fix" the IS-F exhaust with a Tanabe. It may come down to the deal...

The GS460 is a '08 with a great price, and the color combination, Saphire/Tan, that I find irresistable. I can get a not as great (but good) deal on a Black/black 09 IS-F. Decisions, decisions.

rominl

iTrader: (4)

i didn't drive the 450h on the track, but i drove teh 600hl on the track. it was quite some experience, and seeing how the ls600hl did, i could only imagine the gs450h

back to the gs460. it's still a mystery to most about their power rating. a lot of speculations of course. internal to the engine i haven't read any hard evidence on the difference, and personally i would be surprised if they have any difference in the two 460 engines.

obvious difference is the intake of course, and i am not surprised if that makes some difference. i mean, if they are they same, then it doesn't make any sense for the ls460 to have double the filter and intake.

another possibility is marketing. if the gs460 has 380hp, it will literally KILL the gs450h. for about the same price, the power difference will make the 450h very unfavorable. if that's the case, one thing they can easily do is to detune the timing and such on the 460 engine through ecu to lower the power rating.

imho that's more psosible

also look at the previous generation gs430 and ls430. they are almost identical design, but the ls430 had 10 less hp iirc. it's the exact same engine and i believe even the instake was almost the same. so i tend to believe the difference is in the ecu?

LexFather

No at an IS-F event, they had GS's and IS 350s to drive as well. I will track her soon and let u know. I plan to take her to the drag strip at the end of May to see 1/4 mile times.

I think the GS 460 would be the better deal for you. For one if you require, you CAN make it sportier with modifications. With the IS-F you can add maybe 18" tires, a more restricted intake but it still is a sporty car.

Lexus seems to have attacked the rattles with later cars

Since the GS 460 uses the same tranny as the IS-F, maybe drop the IS-F engine in the GS (but talk about a hood bulge lol).

Good post Henry. Lexus has stated they will update engines over time. Another guess is maybe they kept it at 342 so when the 4GS comes, it will have 380 or so, instead of the 2GS to 3GS 300hp same engine fiasco.

rominl

iTrader: (4)

another thing i read before was that when 3gs came out, it came out with gs430. and later news (real or not?) got out saying that lexus was having trouble fitting the 460 engine into the 3gs chassis and were scrambling to resolve that. first of all i don't know if that's true or not, but if so, then maybe that deemed something to be modified affecting the power

mike, if you go to drag strip, i say try to get some better rubber. the stock tires (i hope not runflats!!!) can't really handle the power of the car

maj75

Well, if the IS-F was rocking dual filters, then there would be some support for this theory. I think that noise abatement is a more logical explanation. The air flow pattern resembles no high performance design that I am aware of.

Quite common back in the day. The engines in mid-size muscle cars were often rated higher than the same engine in a pony car, due to the compromises that had to be made to fit the car in the chassis, intake and exhaust manifolds that were less than optimal, as well as more restrictive exhaust.

I hope you are right about the ECU. De-tuning the performance using the ECU is probably the easiest from a design/mfg perspective as all your hard parts are identical, reducing costs. The good news is that it should be relatively straight forward to retune the ECU and have to change/modify only one component.

maj75

I just heard from my dealer, they found me a white IS-F That's the good news. The bad is that it is an '08. Now I am trying to decide between the 08 GS460 and the 08 IS-F. Great deal on either!

rominl

iTrader: (4)

imho nothing wrong with 08 is-f. 09 is just minor face lift, and imho not dramatic enough to justify the premium. i suppose you can get an insane deal on the 08 is-f now

Stormforge

sorry to be bearer of bad news...but retuning the ecu is supposedly impossible. one tuning shop who claims to have cracked toyota' ecu for gains is now under the microscope and the gains reported in the original test vehicle could not be duplicate by others. and it should be noted that many tuning companies in the past have tried to crack toyota's ecu but have failed. do a search on ecu tune and you'll see what i mean.

rominl

iTrader: (4)

some gs460 owners should try to put the ls460 ecu in and see