I'm trying to understand what is involved in a valve body upgrade. Are they basically installing a shift kit with stiffer accumulator springs? And is it just as effective to shim the accumulators as has been done with much success?

I am planning my trans build and will be upgrading the torque converter. My plan is to pull the trans, pull the valve body, shim the accumulators, turn up the line pressure dial, and go back together with a 2800 stall converter (already have a cooler installed). But I'm wondering if it would be foolish not to do a complete valve body upgrade at that time and if it's worth the cost. It's $900 for the converter alone, and around that for a worked valve body too. Too much $$. There is the Trans-go shift kit available for $175 and the accumulator shim process. I'm wondering if this is as effective as a valve body upgrade. Any info would be appreciated.

I also have to plan my LSD rear end upgrade. So need to work things out cheaper, "not cheap out", just not going "all out" in all areas.

 

there was another thread about high stall converters someone was posting about for their gs300. I looked into it and found that the gs300 already has a factory stall speed of 2,700 plus or minus 150. so buying a 2800 stall for your car would be kinda pointless. you would get more bang for your buck if you had your valve body upgraded. yes it included stiffer springs for the accumulators but also the ports in the vb are modified to apply more line pressure to the clutch bands for better holding power. the modification of the accumulator springs is more for firmer shifting mostly. the accumulators for there for shift shock. they help absorb the slam effect when a next gear is applied. by making the springs stiffer, it gives you more of a harsher shift. if your dead set on buying a higher stall converter, a 3200 might be more noticeable but than your ecm might throw a excessive slip code.

 

I’ve read that factory is 2700 also, but PI says that’s bs and they only get 2200 ish out of them. So not sure what to believe yet..

 

I guess whats's important is matching the TC to the cams anyway. If anyone knows how to read cam cards.. can you tell me the rpm range of the BC 264 cams for our engine? Rule of thumb is to go 500 more stall than the starting power range of the cams. Their site wont let me take the pic, but here's a link. Sometimes cams say the rpm range. These don't. But someone good at durations could tell by looking at the specs I'm sure. They said the 264's would kick in about 500rpm later than stock. But weren't totally sure sounded like.
http://www.briancrower.com/makes/toyota/2jzge.shtml

 

I'm also wondering how similar the a650e in the IS300 is to the GS300. I have one available to me for basically nothing in good working condition. Was pulled out for a manual swap. If it's the same, I might just do a complete overhaul on it with the upgrades to minimize down time.