broke_gs

I'm not really sure about your stock exhaust question. Everything seems to be fine with it. I don't really know how much force the backpressure is putting on the turbine. I'm thinking that the only thing the backpressure would do is change the pressure difference so the turbo would not spin as fast. But I can run my boost no problem, so I can't be slowing it down that much. But as to damaging the actualy turbine itself, I'm not sure. Maybe someone else with more experience can chime in. Also, since my wastegate dumps to atmosphere, not all my exhaust gasses go through the stock exhaust.

broke_gs

How is it that I'm the only one talking about this? Is there anyone else on the boards with a Turbo/SC GS300? Swift has been selling their supercharger/turbo systems for a while. I would like to hear from someone with their system on their experience with it and their impressions. I hear people wanting to get one and people in the process. Anyone actually have it? I know there are people here with the GS400 stuff, but what about the GS300?

Richie

I think you are the only active member on here with a turbo conversion on his 2nd gen. GS.

lopes03

Broke_gs nice setup I'm sure it must be fun as hell to drive a GS under boost. I can't wait till mine is done

I am in the process of turboing my car actually it's almost done just need to install the engine management system (greddy E-manage). My setup is a bit more extensive then Broke_gs's. I am running a custom kit. I have a revhard turbo manifold and downpipe, turbonetics T-04E ball bearing turbo, Turbonetics wastegate, Blitz blow-off valve, Hybrid intercooler, 440cc injectors, supra TT fuel pump, AEM fuel pressure regulator, 2mm headgasket, greddy profec-b boost controller, custom intercooler piping. Should all be done later tonight. Going to stop by the shop to pick it up. The only issue I have is with the tranny. For now I have a tranny cooler, but eventually I'm going to have to take a ride down to SRT and get me a valve body upgrade.

Putting up dated pics in my gallery.
turbo install

The issue with the stock exhaust does concern me also. Since I am running at high boost 15psi + I have a 3"inch down pipe which hooks up to my apexi WS exhaust. That let the turbo breath without a problem. In Broke_gs case it is a little different. Since he did not change the compression of his motor he's probably only running 8 to 9 psi. I think this will work fine on a stock exhaust. All the downpipe's I have seen all pretty much bolt up to the stock exhaust. remember the downpipe takes out all of our cats. The only thing that's left restricting is the resonator. Which can simply be taken out by a muffler shop or replaced by installing a race pipe. I would only be concerned about the stock exhaust flow when running over like 12 psi. Then you might get issues regarding back pressure.

This is jut my 2 cents. I am sure there alot more people on this forum that can clarify this issue.

broke_gs

What does the fuel pressure regulator do for you? Can the E-manage effectivly control the fuel flow? If that is the case, I might look into getting that installed on my car.

sirsomo

Im really thinking about turboing my 300. There are tons of IS's out there with FI, so its not really that big of a deal. As Richie mentioned, Sound Performance, SP Engineering and I think Toyomoto have all turboed GS's. There is a shop here in Atlanta that is close to finishing a turbo kit, but we will see how it pans out. Im not a turbo expert, but I have a few questions/comments:

lopes03:
15+psi is a lot. Have you thought about upgrading your internals? The 2jz block is strong but Im not sure I would go over 12 or so without some engine work (besides head gasket). Also, might want to look at getting a torque converter put in with the valve body, depending on your setup that could be a ton of power for your tranny to hold, and a TC should help your times a good bit.

broke gs:
I would think the stock exhaust system would be very restrictive on a turbo GS, how many cats are you running? Your ECU is relearning and trying to adjust. Thats why it starts running rich after it is reset. Im not sure if a stand alone would be a good choice for you, as low as your psi is, but I will let someone with more knowledge address that. Check out is300.net for more answers, they have many more turbo 300s than CL does, also there is a good thread at seloc.net

Richie

Looking foreward to hearing more about your project.

lopes03

A fuel pressure regulator controls the fuel going into the motor. Since we have one built in with our fuel pump, when I upgraded to a supra pump I need to install one along with a return line to the gas tank. E-manage controls, air/fuel ratio like an AFC but with more accuracy, it also controls injectors, timing, and boost.

lopes03

yeah it is a great deal of boost but I won't be running that every day only on high. Daily driving I'll probably be doing like 8. Yeah eventually I would like to do a TC but right now I'm just recovreing from all the money spent already.

The stock exhaust isn't much of an issue for the fact that the down pipe removes all of the cats.

Yeah I've read on is300.net that a bunch of them are having the same problem with there car ecu taking over. I fellow here from a company called SPI has an IS300 and he seems to be running into the same problem. He's going to take a look at my e-manage to see if it can fix his problem.

ScrewFace

Actually with the stock internals and a thicker head gasket, the 2jz-ge block is known to make well over 600whp.

Also if you ever need to upgrade your internals its probabley better to order and bolt on a brand new 2jz-gte block from Toyata for ~$1500... will handle over 900whp

JPI Racing

Short block for $1500? Where do you get that price? They usually go around $1850-$1900.
JPI

broke_gs

Well, I think I fried one of my rings last night. I noticed some smoke while I was driving and popped the hood when I got home. There was oil everywhere towards the back on the passenger side. It seems as though oil was coming up through the plastic elbow on the engine. Brought it into the shop and they said that I probably messed up my piston rings. They will have to run a compression test and a leak-down test to see for sure. Looks like they might have to take the engine apart. This SUCKS!!!

Anyways, the reason I'm posting is I need some suggestions as to what else to do since the engine will be apart. He has some pistons laying around that he can sell to me for cheap, but what else should I get done?

JPI Racing

I would go ahead and put a GTE short block in there.
JPI

ScrewFace

You're right retail is about $2K... dealer prices are a little lower though, notice I used an "~" before "$1500

etnarp

Just food for thought to those thinking of a turbo project:
How dependable does this car NEED to be? ( as in, sole source of transportation?)
Am I willing to spend in excess of 12,000 dollars( conservetively) for a quality installation
Who, other than the tuner, will be able to work on the car if there are problems? Don't depend on Lexus
Is sale value to be a consideration in the future? The % of return on your investment WILL be minimal.
Living with the grief from your better half and the glazed over eyes of your non-enthuseist friends as you explain the concept of boost.
I ,of course, ignored this advice, gave a lot of money to Larry Prebis at Sound Performance to turn my docile sweet running GS into a hard cold starting, rough idling, check engine light flashing, no vsc half the time,smoke the pilot sports from a 30 punch and wipe the grin off the face of the guy in the 911, Sleeper.
Guess the bottom line is there are no shortcuts or cheap methods to turn your GS into a high performance car, but the reward is a truly unique vehicle. In fairness to SP,I haven't been able to get the car back to them to address these minor problems- hopefully this spring.