Aron9000

Not that I hate this engine, its been the queen of smooth, silky, quiet operation. And its been dead nuts reliable for the past 20k miles and 3 years now. Plus its kind of fun paired with the 5 speed, rev it and its "reasonably" brisk.

Its just that I've owned two Camaro Z28's with the LS1 V8, a 1999 auto, and a 1998 manual. Both had over 100k miles on them when I sold them, both were very reliable. Its just that they got better gas mileage than my 2JZ, and had about double the horsepower, in cars that weighed about the same(ie 3400-3500lbs). Both of those cars would straight HAUL *** compared to the Lexus. Granted the Lexus is a much better car overall, way better made, better suspension, quieter, way nicer interior, etc, etc, etc.

Its just crazy how much better the engine and powertrain was in those Camaros that cost half as much as a Lexus SC back in the day. Granted the interiors looked like they were made by Fischer Price, but its so annoying to drive such a nice/beautiful car like the Lexus and know that you got ripped off in the horsepower wars, plus you get worse gas mileage.

t2d2

iTrader: (8)

Engines have come a long ways since the mid-90s, that's for sure. Double or triple the horsepower now with nearly the same mpg. If only cars were as light as they used to be with minimal safety features... Has anyone done a LS1 swap into a SC?

Sylexus

iTrader: (1)

My first car was a 1st gen GS300 and back then I noticed it was a gas guzzler and it puzzled me because I was like '' This isn't a v8!'' but now that I have the SC400, this feels on par or maybe worse than the GS was on Gas Mileage. I personally will be swapping an LM7 5.3L LS engine in seeing as they can be had for 500-900 dollars.

jennie

People have swapped LS engines into the SC. Search in the build thread section. Turbodremz comes to mind.

jennie

I think the slow 2JZ gives us all an excuse to do a GTE swap. I thought my IS250s highway gas mileage was pretty good until my friend with FD + LS1 told me can also easily get 30 MPG. Same gas mileage, half the power.

KahnBB6

iTrader: (5)

Fed up? Personally? Nope. The JZ engine is an amazing design. Sure better fuel economy would be nice but I'd rather have Japan's answer to the Chrysler 426 Hemi and Ford 427 as-is since it is so capable.

Also, remember that this is a cast-iron inline-six. Until very recently with advancements from BMW, Chevy's 4.2L truck inline-six and the short-lived Benz OM606 turbo-diesel DOHC inline-six, this engine type was never known for its stellar fuel economy.

Toyota did make a small jump in efficiency with the 1JZ-FSE and 2JZ-FSE Japan-only engines which broke 30mpg but they were automatic only, direct-injection ("D4" which is very similar to the "D4-S" used in the BRZ/FR-S boxer engine) full ECU controlled DBW throttle, and were never offered in turbocharged form. the highest power available from them was 220hp-- basically the same as what we have with a far less beefy JZ.

The LSx V8 engines are some amazing engineering. I was very, very close to buying a 2004 Pontiac GTO 5.7L 6-speed before I bought my SC. I just couldn't do purple factory paint on purple interior.

You have to remember that these engines were designed in 1990-1991 and at the time they were state of the art and were subject to fuel economy standards and CAFE rules of the early 90's. They were also used in mostly high end Toyotas. The thinking was a bit different then and it was easier to forgive a low 20's highway fuel economy figure in a luxury car (or a sports car like the MKIV Supra). The fuel economy of the same-era Camaro SS and Pontiac Trans Am were slight oddities once the 1997 revisions went on sale.

LSx swaps are great in SC's but few have done them. I'm going low-boost (15psi as limited by local premium fuel) GTE in my car. Absolutely not cost-effective at all but you do get all the horsepower you'd expect at that level from Toyota's most famous performance engine. Fuel economy won't change much I imagine but for that... I'll get a second small car.

Ali SC3

iTrader: (10)

they are designed to prevent detonation and increase performance not to save fuel

2JZ_GTE or 2JZGE

2 = 2nd generation
JZ = Inline 6 engine block designation
G = Performance wide-angle valve DOHC
T = Turbocharged
E = Electronic fuel injection

If it was ever intended to get good gas mileage, it would have been a 2JZ-FSE
which they did make as Kahn noted it just never took off cause while it got good gas mileage the direct injection made all modifying and tuning very non-straight forward and it was not a performance 2jz anymore.
2 = 2nd generation
JZ = Inline 6 engine block designation
F = Economy narrow-angle valve DOHC
SE = D-4 Gasoline direct injection (1990s)

http://en.wikipedia.org/wiki/List_of_Toyota_engines

Tabaka

iTrader: (8)

My 2 ton '99 Ford Expedition with a 4.6L V8 gets better gas mileage than my NA GE engine.

Bdub215

iTrader: (1)

It boils down to final drive ratio and gearing. Personally I have a SC300 5 speed and as a comparison a ES300 5 speed. Both Iron block/ alloy head 6 cylinders. Both cars have similar gearing but the key difference is the differential. My ES is equipped with a 3.62 FD and the SC a 4.08. As far as cruising speed: My SC is 65mph @2800 Rpms to attempt to get decent economy on the highway. Any faster and I can watch my gas gauge go down and I'm getting passed left and right. The ES is 75-77 MPH (depending on the tire setup) at 2800 Rpms and does better on gas because the engine spins up slower and I can keep up with traffic.

Sent from my iPhone using Tapatalk

T0ked

iTrader: (2)

Of course now a days it can be frustrating. And Lexus is kinda known for sitting on engine development, but you have to remember when the 2JZ was introduced, 225hp was a lot. The 300ZX and Supra were pushing ~320. The M3 was just a bit more than the 2JZ, and the ZR1 was king of the hill with way less than 400hp. Gas was also $1 for 93octane. Different times, and the SC actually lasts this long for us to be able to complain.

Duck05

While it is not my daily driver Honda Civic (35-37 mpg on regular) the SC300 at 19-23 MPG on premium is not all that horrible. I see on the freeway so many SUVs and large pickup trucks that can't be getting more that 18-20 MPG and often wonder what those folks devote to those vehicles in the way of fuel costs.

I am only driving the SC once a week to work and whatever weekend events arise - I'd like to drive it every day but just not that practical with the fuel and tire situation (19s with 30 and 35 ratios) compared to a Civic.....

Fed up? No. Wish it was way better - sure. At 22 years plus old it is still a fun car....

mecheng10

if you bought an sc an expected it to be fuel efficient....
you are going to have a bad time.

back in the day it was, but not by todays standards. and the people who bought this car off the showroom floor ($50000 dollars back in the day) didn't really care about fuel economy.

now... all they are to most people are a play thing. a cheaper version of a supra. with all the same potential.
who cares what mpg you got when you can kick the *** of that 150k Ferrari next to you in a 22 year old car...

ArkLaTexSC

NA 2J
There's your issue!

....

But my 1UZ gets like 14 mpg, so, yeah. ECU fix should help with that. But I only ever own cars with terrible gas mileage.

KahnBB6

iTrader: (5)

^^ This, to a T. If you look at the SC's competition that has survived along with it, not many cars are left standing let alone have such cult popularity as tuner cars.

I put a 4.27 ratio into my car giving it perhaps 1mpg less fuel economy than a 5-speed normally has, depending on how I drive it. I hope to gain back 1-2mpg highway when I change to my 3.77 ratio but I don't ever expect stellar fuel economy. City economy with even with stock turbos I imagine might get slightly worse rather than better but it might be on par with a V8 M3's city fuel economy.

The ES300 V6 mentioned in a previous post probably still gets better fuel economy than an inline-six 2JZ even if the FD ratios were matched. Other than packaging there is a reason so many manufacturers have been using V6's in recent years. Current fuel injection technology could change this for a while, however.

INTIMAZY

iTrader: (5)

Bingo!!!!

My 3.26 out of a SC430 combined with R154 and a laggy single actually does great on the highway. Just need to lower the rpm.

LSx motors pretty much idle on the highway.
Well, maybe not idle. But it's really close with the tall gearing of a T56