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Discussion Starter #1
Well, here it is folks..

At 7.5 psi:
310 hp @ 6000rpm
305 ft/lbs @ 2600 rpm

At 10.5 psi:
364.1 hp @ 6000 rpm
329 ftlbs @ 4600 rpm (roughly)

Here's a 10.5 psi dyno graph (note the time). They're currently tuning for 12 psi just to see what it'll do.. enjoy..



He's going to send me the 7.5 and 12 psi when he gets a chance. I asked for a baseline graph overlay also (compare stock versus 'forced').. I'll post those when I get a chance..

This was done on TurboIS's (forum member) 2001 Lexus IS300 in 4th gear on a DynoJet dynamometer with a single turbo front mount intercooler setup..

I know this is the general discussion forum but I'm sure there are some people that don't frequent the performance mods forum and would like to see this.. so I apologize..

[This message has been edited by oh-dawg (edited October 09, 2000).]

[This message has been edited by oh-dawg (edited October 09, 2000).]
 

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Originally posted by dude:
Is the auto tranny able to handle that much power??
I doubt that it would be able to. My friend's getting a Chip for his Tiptronic Audi S4 and apparently he'll have to get a TIP chip in addition to handle the extra 50 horses.... In this case you're talking about tremendous increases in horsepower and more importantly TORQUE...
Eric..
 

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Originally posted by EricK:
I doubt that it would be able to. My friend's getting a Chip for his Tiptronic Audi S4 and apparently he'll have to get a TIP chip in addition to handle the extra 50 horses.... In this case you're talking about tremendous increases in horsepower and more importantly TORQUE...
Eric..

That's what I thought.....So basically this turbo setup is pointless....Unless they've included a modified auto tranny (or a manual) to withstand the massive horsepower and torque increase, which I highly doubt.
 

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TEG had written before that the auto tranny in the IS300 is the same used in the GS400. The GS400 is 300+hp stock, and if they are the same, a turbo IS with about 310 HP should hold up fine under the stock clutch (that's an assumption I hope holds true)

????????
 

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Yes, I *had* heard that the IS300 trans is the same as the GS400 and therefore should stand up to those power levels. Part of my reason for buying the car, is that I am expecting to be able to get to 300hp and still be reliable.

Anyways - a Lexus tech once told me "be careful about those assumptions, because the factory *could* have used some different components that aren't able to handle the same torque as the GS400." We shall see. The basic unit should be very robust. It is possible that some internal components (torque converter?) or the differential could need upgrades, but with any luck we should see reliable power delivery with only engine mods...
 

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Discussion Starter #10
I had spoken to the guys at XS and basically, there are problems with the transmission. I'm going to paste what I received from them via email. But to summarize, the trannie doesn't have a problem with the power. The problem is with the shifting. Mysteriously, it won't shift gears if the car is making more than 280-290 horsepower. They go into detail about why this is, but they also say they have a modification to cure the shifting problem. I'm also going to attach a dyno graph that they emailed me with stock horsepower, 7.5 psi, 10.5 psi, and 12 psi of boost.

One last thing, THIS IS NOT MY CAR. This is 'TurboIS's car.

From Andy @ XS Engineering:
Here's the dynosheets @ 7.5, 10.5, 12.0 psi, and stock. Unfortunately the 7.5 and the stock were sampled before we learned how to keep the car in one gear, so you only have a portion of the power curve. Note the massive powerband with over 300 ft/lbs. of torque between 2700-redline. Please keep in mind also that this turbo was sized for the STREET. More power can be easily had by simply using a bigger turbo, but we figure most Lexus owners don't want that. They want a massive, wide power band that can be used to smoke C5s, Supras, RX-7s, M3s, Type-S's etc. Our turbo sizing shows that superchargers are useless against a properly sized turbo. In case the owner does want massive power, no problem, because we can build 700+ horsepower 2JZs as well.

Keep in mind that all of this is being done with the stock ECU. We do believe in aftermarket injection, but we do not believe that Lexus owners would like to ruin the fuel economy and near perfect driveability. Nor do they want to wait 2 or 3 weeks to install and tune an aftermarket system. So to supply fuel for these horsepower levels, we've done quite a bit to the fuel system including a much larger fuel pump, ECU mods, Apex computers, etc. All testing was also performed with a Greddy TVVC knob type boost controller. Keep in mind that even MORE torque at an EARLIER rpm can be made with an Apex AVC-R because the turbo will light up even quicker. As far as TurboIS's car goes, he has been seriously inquiring about a MoTec M8 and a full out Level 10 transmission. If this is the case, we will go into the 600+ daily driven horsepower territory with this car.

As for shifting, we have already exceeded the limit of the stock transmission as far as its ability to shift. The IS trans can shift at a limit of 280-90 horsepower. We have already fabricated a trans cooler system and are working on a valve body that will turn up the trans' line pressure enabling the trans to shift at 300 plus horsepower. The trans seems to hold up fine at 386 horsepower and 355 ft/lbs of torque, but it won't shift. But let me tell you, 386 hp in second gear = NO TRACTION (with stock wheels and tires) and in third gear it will set you back in the seat pretty good. The valve body modification will allow the trans to shift. We will probably make the Stage 1 kit at right around 260 horsepower and a stage 2 kit at around 310 horsepower the would include a valve body and a convertor. Further development will yield a 380 horsepower kit and some sort of unlimited kit as our cast ductile iron manifold fits both T3 and T04 turbine flanges.

Currently the car is being taken apart and everything is being sent out to chrome and polish including the intake manifold, valve covers, etc. After the car gets back from SEMA, we will continue testing on the transmission.

 

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Discussion Starter #11
Sorry for all these images.. but damn.. I have to post the 12.0 psi dyno graph too.. it makes some damn impressive numbers..



For those with slow connections and cant wait for the picture to load:

386.6 horsepower
355.6 ft/lbs torque


[This message has been edited by oh-dawg (edited October 09, 2000).]
 

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Any idea how much they're asking for for a complete stage 2 modifications??? (including the transmission mods)?? And how realiable is the transmission with the mods???

Thanks.
 

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Discussion Starter #13
Well, I'm no expert on automatics (or 5-speeds for that matter).. but he said there's a valve body in the trannie.. and I guess there's some type of pressure regulator that maintains line pressure so that the automatic can shift between gears.. when the power increases, the regulator gets weak and can't maintain proper pressure to execute clean shifts.. so what they plan to do is buy a new valve body and modify it to hold more pressure.. he mentioned something about a higher tension spring inside.. but again, I dunno whats totally involved.. he said its not a problem other than the fact a valve body is expensive.. he said it'd still shift smoothly.. it doesnt sound like a major trannie upgrade or anything.. basically just replacing a part..

They havent released a price yet because the car is still in its R&D stage.. once they get everything together, then they'll sit down and work out a price for the whole kit..

After they get back from SEMA, I hope to head down there to check it out.. if there aren't pictures of it by then, I'll be sure to get some..
 

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what would be the 0-60 time of this IS...
 

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Maybe I should reconsider my plans now..... stage 2 engine mods with a manual tranny instead of an auto tranny......

Ummmm.....sounds very yummy indeed!!
 

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I have Got to bring My IS to them.... What Will 10K Get me? I have to have this done! Can you say FFFAAAAAASSSSSTTTT????

I'm im love.......

BMWEATR

OH-DAWG Please Please Please, e-mail me all these graphs and specs. I am going to take it to a top notch guy here in town, I need to get mine done NOW! I want to race this puppy!

[email protected]

[This message has been edited by TheImmortalBlueDuck (edited October 10, 2000).]
 

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Discussion Starter #18
0-60 ? well, I dont think the TRD limited-slip is in the car yet, but the owner did purchase one.. but it sounds like its traction limited considering its not getting any traction in 2nd gear.. but I'd say if they resolved the traction issue, I'd say in the neighborhood of 4 seconds.. with high 12 second 1/4 mile.. for comparison:

Porsche 911 Turbo (400hp), 0-60 3.9, 1/4 mile at 12.3 @ 116mph

Ferrari 360 Modena F1 (400hp), 0-60 4.6, 1/4 mile at 13.1 @ 110mph (weighing in at 3300lbs, lighter than the 911)

(these #s are from http://www.caranddriver.com )
 

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Well, good thing there are shops that make upgraded auto trannies. Like L10. Although they might not be as good as once thought. But hey, maybe Sound Performance...they have (or are testing and will have) an tranny upgrade for the Supra which is better, cheaper, and warrantied, compared to the L10 one. And SP has a 9.54 sec fully street Supra...I mean full street. A/C, stereo, seats, IRS, etc. Big congrats to them! K den.
 
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