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Speedy · 09-18-2007, 01:53 PM

Quote:

Originally Posted by mastacox

I have to say, after reading the entire SupraForums thread on this it sounds like you may be going too much on the accumulators. According to a guy in that thread, a 5/8" shim is essentially the same as a rod, since it ends up increasing the rate of the spring so much it can't compress during a shift...

You have been beating your transmission pretty heavily, but I would say you don't want to go any higher than a 1/2" shim unless you're desperately trying to avert transmission failure, or are drag racing.

Most of the SupraForums guys seem to aim for shims that are between .236" and .315" (6mm - 8mm). These are guys with 400+ hp too... 1/2" is a big jump; do we have first-hand evidence that 1/2" is really necessary for a 4Runner/Truck, or is that just "hear-say"? From what guys say on the board, 6mm is firm, 8mm is starting to be pretty harsh, and beyond that...

The guy on CT that did this over the weekend reported needing more shim height. Here's the post:

http://www.customtacos.com/forum/sho...6&postcount=57

"1. i didn't take pics (kinda hard with tranny fluid and all over your hands).

take the time to make a cardboard cutout and place the vb bolts in it. it will save a TON of headaches later.

2. follow the directions here (this is exactly what mine looked liked minus the turning of the pressure change thingy and one extra bolt in the filter) http://jkwebdesign.net/lsocbb/viewtopic.php?t=1915

3. the only thing you can't do to the a340e(f) is the vb fluid pressure change (i looked at the vb for an hour...it wasn't there)

4. the 1-2 accumulator will need more shims over the 2-3 and 3-4 accumulators.

5. i used regular round flat washers (stainless).

6. i used approx 1/2in of shims on ALL accumulators.

end result of the accumulator shimming:

7. 1-2 shift is better over stock but can use some more shims (i want to use 7/8in shims when i pull it apart again).

8. 2-3 shift - this was the most surprising. it shifts VERY firm compared to stock. very pleasing when you got it floored and it hits the 2-3 shift. if i wasn't running 285/50/18 in the rear it would have broken them loose (yea...on a 2.7l too).

9. 3-4 shift - also, VERY firm and pleasing. Not quite as hard as the 2-3 but still you can tell it definitely shifts firmer.

10. you will need an extra person when you reinstall the vb. probably need 2 people anyway. the vb is heavier then it looks (probably 10-13lbs).

11. in the a340f (which is in prerunners and dcabs) expect to use about 6.5qts of tranny fluid on the refill.

me and my next door neighbor went for a drive....ran 4/10ths of a mile (which should be a 1/4 mile and it made it somewhere between 87-90 and the end of the 4/10ths. which i think is impressive for a 2.7l prerunner.

i want to take it track-n-tune night at the g'ville raceway soon to get a slip at least.

overall, nice improvement. i keep watch on the temp gauge and it was normal for city/highway driving.

enjoy."

Some of the shim height will be determined by whether or not you have the VB pressure adjustment available. The Supra guys DO and they were turning that up at the same time as the shims meaning they'd need less shim height to achieve the same effect.