kmn5

Hey All,
I know there's a bunch of you turbo SC owners out there.
But I think most of you guys went with a turbo kit, right?

But how many of you guys went all out and swapped in a 2JZGTE motor and ECU?
Will the motor bolt up OK to the stock 5 speed?
Also how did you rig the ECU? Run both the stock and supra one???
I doubt the factory one can be elinated completly.

Thanks for any info
If it's not too tough, or if there's someone that could guide me somewhat one the install.
I'll pick up the turbo motor.

Thanks
Ken
kmn5@excite.com

The Ikon

The motors are the same aren't they? So wouldn't it be cheaper to get a turbo added to a SC3?

I don't know but it seems cheaper. Unless you can get a motor at a Crack Head price!!!

I drive the Big Brother with no exp., so I'm just adding my .02 cts..

SC300T

The 6spd bolts right up to the NA block. I would assume that the opposite is true, but if you're going that far, why would you leave the 5spd in?

The engines are essentially the same block. TT has different pistons and later ones 97? had better rods, but I haven't heard of throwing rods on these.

There are plusses and minuses for each engine, but I think it doesn't matter very much. Depends on what you want to do with it.
The NA engine has more efficient intake system.
The NA intake limits turbo size and strut bracing.
The NA ignition is distributor based, an advantage in that you can retard the timing for higher boost.
The NA ECU and turbo ECU are totally different.
If you're going 2JZGTE, you're spending $10-$20k for just stock TT power.
I've spent $8000 on mods including turbo kit and have exceeded the stock TT power by a good margin.

kmn5

Thanks for the input.
My reseaoning for considering the TT engine is that I won't have to lower comnpression..

But the big hurtle I see is wiring up the ECU...
I know someone selling a TT engine and ECU for $2,900
So I figured it might be a worthwhile modded.
I turbo kit I can probably do myslef self, but the engine swap will require a competant supra shop.

kmn5

another question,
will the TT supra manifold fit into the SC300 engine bay?

Thanks
Ken

philauldridge

Yes, it CAN be done (I think).. I'm hopefully in the final stage of my own conversion. So far, I'm up to close to $20k, this included a rebuilt 2JZGTE engine, NEW harness, NEW Supra ECU, HKS Intercooler, Vein Pressure Controller, new GREDDY twin exhaust, downpipe, etc., etc., etc. The engine fits fairly easily on the stock mounts, but you will have to do a few mods. I scrapped the complicated hydraulically driven cooling fan from the Supra for a standard fan, and we had to buy the Supra power steering pump with remote tank for clearance. If you can really get a COMPLETE engine with ALL accessories, harness, and ECU, you will be miles ahead

If you want serious power, this is the way to go. All research indicates that an easy 450 HP should come from this setup without seriously taxing the engine. Prob with the stock SC engine is higher compression, which requires a somewhat micky mouse approach (thicker head gasket or shorter rods) to get the compression down to the point where serious turbo charging can occur, and, of course, the Supra engine was specifically designed for this application.

You can go much cheaper if you can find a COMPLETE GTE engine WITH full engine harness and ECU.
No, youCAN'T leave it the LEXUS ECU, and this is where the serious voodoo comes in. You will need full factory manuals for both cars, and hours and hours of poring over the ECU schematics to make the cross-references. Fortunately, the cars are BOTH Toyota, and the ECUs are VERY similar (I suspect the hardware is identical, with just software changes). Most of the wire colors are even the same. However, except for the main connectors to the ECU itself, all the other connectors are different, and this is where the work comes in. Removing each wire from the original SUPRA connector and relocating it into the orig. LEXUS connector so it can plug into the interior harness. I'm currently bogged down on this part of my own project, but know I will eventually conquer it!

The LEXUS 5 speed will bolt right up to the Supra engine with no mods at all. Not quite so for the 6 speed (It WILL bolt up, but then requires a SUPRA rear-end for correct gearing, and a shortened driveshaft. Most people say the 5 speed gearing is actually better for the turboed engine, with the only issue being how long the 5 speed can handle the additional torque.

Hope this helps!

phil

SC300T

"micky mouse approach?" "the Supra engine was specifically designed for this application?"

I guess there are a lot of "micky mouse" people out there making perfectly reliable 600+ horses with the NA engine including a sub 10 second drag Supra.

Those that are using the GE motor are WAY ahead $$$ wise on this... You also have NO proof that the GTE is ANY better than the GE.

The pistons are what reduces the compression on the GTE, not the rods. Also, if rods on these engines were failing, you'd have a point, but truth is rods DON'T fail under normal high boost circumstances on the GE.

IMO, the GTE complete swap is a waste of money.

As far as the $20k on your swap.... If I had the same budget, and kept the NA engine, I'd have a lot more power than you, with the same reliability. Your $20K project with stock twins, upgraded exhaust, intercooler, VPC, is around BPU+, which is probably good for 400-450RWHP, (not bad, but not exactly the best power for the money.) The stock twins are good for around 400-450RWHP MAX....

I'm around 400RWHP on less than half the money, and only $2000 away from another 100RWHP by lowering the compression and adding a boost controller. All this on a GE with over 126k miles on it.

SP can install the low compression gasket for around $1000, the gasket itself is $250ish.

Also, much progress has been made lately on manifolds, and such. SP has a tubular manifold that has trememdous flow and will work on the NA engine. They also have an Intake plentum that does the same.

Take Ethan's car, for a good example.... SP has thoroughly reworked his NA engine, resulting in a show-quality car with well over 600RWHP by the time they're done. If SP couldn't get the numbers, would they leave the NA engine in? NO.

Same with Toyomoto. Do they generally replace the GE with the GTE? NO.

I think its unwise to guide people into thinking that they have to give up their NA engines to get good power.

philauldridge

Your points are well taken, and believe me, if I had known the amount of downtime and
difficulty of ECU wiring/conversion, I would NEVER have taken on this project.

I suspect there are only one or two shops in the entire country who truly have the
expertise to properly install a SUPRA TT in an SC300, and I have found, the hard
way, that my local shop, in spite of all their bravado at the beginning, is not
one of the experts. I WILL soon complete the project, and expect to be well-pleased
with the results.

However, as you suggest, I now see that removing the head and replacing
manifolds is a trivial task compared to the mind-boggling job of cross-referencing
all these ECU connections.

Happy driving!

SC300T

I too share your grief at times. Its such a rewarding car to have to travel so far to reach a competent shop. I am fortunate to be only 5 hours away from SP, so I can drop it off for a month or so for work.

Even installing a "mere" turbo kit was a challenge for me, although well worth the blood, sweat and tears. I feel that I know the car much better and can talk about future upgrades without feeling like an idiot. The whole process was pretty difficult and gives me perspective on the wizardry of guys like Lance, Larry and Jarrett. Local shops would just not give me any confidence. My Lexus dealer replaced the clutch, and while picking the car up, I asked him how it was running,--- he said pretty good, although it was "loading up a little bit".... I got in the car and it ran like crap, with sputtering, no boost, wanted to die on me. At home, I quickly realized the bottom intercooler hose had worked loose during the clutch install... I'm thinking.... Has this guy ever driven a turbo?

There are so many unspoken techniques when it comes to working on these things that make the shadetree mechanic scratch his head. Many calls to Toyomoto for lessons like "oh, so that's how you do it...." Many of Lance's techniques could be found in NO repair manual, yet are great timesavers. One is removing the oil pan without removing the engine. Another is drilling into the block. Yikes!!!! They do make it look easy, though.

I've found that of the three gurus, Larry@SP is the most accessible and is willing to take some time to discuss things. Lance is a magician, knows these things inside and out and was a trememdous help, but is painfully slow in getting things done. Toyomoto's kit was amazingly thorough, with every clamp, fixture and piece necessary for the 400 or so hp. The instructions were a bit sketchy with no pictures, but anyone going with the Toyomoto kit can e-mail me for install help.

To anyone thinking of going turbo---Best money ever spent!