Lexus GS300 Valve Body

I have been way busy lately spending a lot of time putting my GS300 back to stock. Or at least that was the original plan. I was going to return the drivetrain back to stock and get the car ready to sell, but its a bit too difficult to return the car back to stock. So instead, Peter at XS is putting in a stock block (I had a Supra TT block before), stock head, with an Apexi 2.1mm metal headgasket for a 9.4:1 compression ratio, a fresh transmission (my old one is smoked), and a new higher stall speed torque converter. I will be leaving it turbocharged, but with a smaller turbo this time (straight T04E 57T) so the car will be easier and quicker to drive around town at approximately 10psi of boost or so. This time, I redid the valve body of the transmission myself. Previously Koji helped me to mod the valve body, but the original transmission was already slipping considerably. After the valve body work the transmission stopped slipping for a while at 430whp, but eventually took a shit after 15,000 miles. So this time I modified the valve body first on a new fresh transmission before any slipping occurred in hopes of withstanding 380whp (the target whp of the smaller turbo setup). My buddy Ron in Nevada who used to build V8 trannies told me how to modify the valve body. Basically I changed out the accumulator springs, enlarged a couple of the oil passages in the plates, and cranked up the line pressure. There is pretty kick ass thread on with quite a bit of information on the Toyota A340E trans, but the GS300 has an A650E so its a bit different inside. It was a bitch since this is my first time playing with a automatic valve body. We’ll see if I got the skillz or not pretty soon. If it shifts quick then I’ll be stylin’.

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Tell me that doesn’t look confusing. Inside is a complete clusterfuck. It’s about $700 if you send it out to Level 10 or IPT, but my buddy Ron insisted that I could do it myself so I decided to take the challenge. Its just like building a Rotary engine: its all about the details. My hands were way too oily to be taking pictures and I’m not even trying to be the cool guy with a build thread on the Lexus forum. I got better shit to do with my time than trying the be the man in a virtual world of misinformation and bullshit.

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