!!Speedy's Supercharger Thread!!

[mt_goat]

Originally Posted by mokai

Oh yea..Huge difference in performance..I have been averaging 19.5 miles per gallon with the S/C and URD 7th and that was what I use to get when naturally aspirated too..

Ill take 100 HP and the same MPG any day

What A/F are you running?

[Speedy]

Originally Posted by mokai

Oh yea..Huge difference in performance..I have been averaging 19.5 miles per gallon with the S/C and URD 7th and that was what I use to get when naturally aspirated too..

Ill take 100 HP and the same MPG any day

During tuning with tons of WOT and short around town trips I got an amazing 17.X MPG. I've been doing more "normal" driving to check my mileage after the SC. Prior I was around 20 MPG.

[mastacox]

This "shimming the accumulators" discovery has been a significant breakthrough... I think this is what I will plan on doing

[Speedy]

Originally Posted by mastacox

This "shimming the accumulators" discovery has been a significant breakthrough... I think this is what I will plan on doing

That's what I'd suggest.

[mastacox]

Originally Posted by QSVeilside

If my trans has a pressure adjustment feature, I'll stick with no more than a 5/8" shim in the 1-2 accumulator, and 1/2" shims in the 2-3 and 3-O accumulators...

If there is no pressure adjustment, a rod will be placed in the 1-2 shift accumulator to eliminate all spring travel, and 5/8" shims will be placed in the 2-3 and 3-O accumulators.

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...

[Speedy]

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.

[QSVeilside]

Masta -

Speedy quoted the first review on CT. 03Taco, (has a 2.7L), said that there was no pressure adjustment feature on his VB... and went on to mention he thinks more shimming needs to be done. Hence, my comment on what I would do in each case - with or without pressure adjustment.

Speedy -

Considering the length of the shift, this mod probably cuts down the 0-60 time significantly. The vid I sent earlier clocked around a low 6 second 0-60. I wouldn't be surprised to see this mod with the lighter wheels take it down to a mid to high 5.

We have a first to second shift vid to make a before and after comparison when I'm done.

[Speedy]

Originally Posted by QSVeilside

We have a first to second shift vid to make a before and after comparison when I'm done.

That'll tell the tale.

[Speedy]

I'm posting a little update I got from QSVeilside over on CT. He's done the DIY valve body mod with success. I'll let him give his own details, but bottom line it works and only costs your time and a few washers.

[QSVeilside]

Originally Posted by Speedy

I'm posting a little update I got from QSVeilside over on CT. He's done the DIY valve body mod with success. I'll let him give his own details, but bottom line it works and only costs your time and a few washers.

I had my tuner work on the VB on Tuesday.

Several notes... but first things first....

A big thanks goes to Speedy - his due diligence just saved us some $$$, and/or prolonged the life of our granny tranny

1. There is a pressure valve on the 2000 4runner VB. However, it was adjusted to the max setting already. There is no "A" indicator as shown on the installation guide.

2. Went with a 5/8" aluminum shim in the 1-2 accmulator. 1/2" shims in the other two.

3. 1-2 shift is still sluggish, but takes signifianctly less time than before. 2-3 and 3-O upshifts are great.

4. Downshifting under WOT snaps you back into the seat. No hesitation. 2-1 shift chirps the tires. The time between shifts is reduced. This applies to upshifting as well as downshifting.

5. There are some drawbacks to shimming the 3-O accumulator- This is difficult to explain... Going down from O-3 on light throttle but with load, (example is going from flat ground to uphill) is SNAPPY. There is also a delay in going from park to reverse, and reverse to drive... This however improves and returns to normal if repeated. We were warned about these adverse effects in the supraforums post - indicating that if we touch the 3-O accumulator, we risk changing the quality of the shift to reverse, etc.

All in all, the second guinea pig thinks this is a terrific mod. I recommend that you DO NOT TOUCH the 3-O accumulator. Follow Raven's recommendation.

In retrospect, I would follow 03Taco's advice and go with a 7/8" shim in the 1-2 accumulator. The reason it was avoided in this particular case was because the VB HAS a pressure adjustment feature - I assume it is at max - line is horizontal.

Ideal modification: 7/8" shim in the 1-2 accumulator. 5/8" shim in the 2-3 accumulator. No 3-O shim.

Speedy - I know you were concerned about how the shifts feel when driving around normally. I can tell you that shimming the VB to this degree does NOT affect normal driving whatsoever. The shifts are completely docile and in no way can I feel a difference. In regard to your question, the pressure valve was not adjusted. As pictured, there is a "keeper" that holds the position. If it is adjusted beyond that, it may or may not stay in place. I see what you are saying about pushing the valve inward, (not rotating it). Unfortunately, that was not experimented with.

The tuner mentioned that there are many things to hold in place when reinstalling the VB - which can be difficult due to the shims. Make sure you have another set of hands ready.



Pics

Valve Body Removed: Showing Accumulators



BOTH Sides of Valve Body:





Pressure Valve:

[mokai]

Anybody here have a hard time with the USB to serial adapter for connecting to the URD 7th injector ECU..I can not get mine to work..I have to use my work laptop that has a serial port on it..But my personal lap top has no serial port so I have been trying to get the USB adapter to work and I get nothing..

Brian ,Gadget and Nathan at URD have been very helpful to me in working on all of this..They sent me a custom map to eliminate my High gear low RPM ping..THe new map works great..The ping is gone..And the Truck just drives better over all..

Ill be installing the 2.2 pulley next week and am looking forward to seeing the difference..

Wish I could get my computer to work, I dont have access to my work computer all the time...

[Speedy]

Originally Posted by mokai

Anybody here have a hard time with the USB to serial adapter for connecting to the URD 7th injector ECU..I can not get mine to work..I have to use my work laptop that has a serial port on it..But my personal lap top has no serial port so I have been trying to get the USB adapter to work and I get nothing..

Brian ,Gadget and Nathan at URD have been very helpful to me in working on all of this..They sent me a custom map to eliminate my High gear low RPM ping..THe new map works great..The ping is gone..And the Truck just drives better over all..

Ill be installing the 2.2 pulley next week and am looking forward to seeing the difference..

Wish I could get my computer to work, I dont have access to my work computer all the time...

My USB to serial adapter worked fine. Just make sure you plug it in after the computer boots up. I was using Windows XP on mine.

[Stevo3]

So hows your rig runnin Speedy? havent heard from ya in a while.

[Speedy]

Originally Posted by Stevo3

So hows your rig runnin Speedy? havent heard from ya in a while.

Swimmingly. I'm going to double check my map now that the temps are cooling down just to be sure it's still locked in. I tuned it in 100 degree weather and now it's in the mid 60s.

I'm planning a dyno session soon to see where I'm at as well and will post an update. I'm hoping for around 225 - 230 RWHP. It sure feels strong and not a lick of trouble.

I may also dyno the coolant bypass mod while I'm there depending on what the guy charges for dyno time.

I was considering DT headers, but heard a few issues and decided to hold off. It looks like too much of a PITA for me to do the install myself and the shop wants $600 for the install. I don't wanna get into a situation where I have to have them installed/removed/reinstalled as that'd get pricey QUICK. I gotta decide what to do on that front.

The truck is plenty fast at this point, so adding any add'l performance goodies isn't really necessary as I've exceeded my original goal, but we'll see.

I've got a $50 cert for Performance Products if anyone has suggestions on what to get with that. It expires soon so I need to use it. I'd like some kind of dry high flow air filter maybe, but have no idea what to get. Definitely not K&N though.

[koda4]

Here's a link to info on the valve body springs and what they control for those interested in the valve body spring modification with spacers.

http://www.autoshop101.com/forms/AT08.pdf

koda4

[Speedy]

I was finally able to keep my foot out of it long enough to get a good determination of gas mileage after the Supercharger vs. stock.

Stock I got 21.05 MPG over a 4 tank average using 93 octane fuel.
Supercharged I got 19.34 MPG. That was only on one tank, but that's the best I can do as driving this thing is just too much fun.

When driving it in a "fun" way I'm getting 17-18 MPG consistently.

The truck is running better than ever, the AFR is right where I want it under WOT (11.5 - 11.8), and my fuel trims in closed loop are about zero for the most part. I don't think I could ask for more than that.

[spaber05]

Speedy, you seem to keep all us sc'd guys updated so here's a question:
Lately, I've noticed a LOUD droning coming from under the hood at certain RPMS, namely 1200 or so and a lil above 2K. Its much more noticeable when I first start her up, so basically a high idle when its cold out. I'm praying its not the SC but Im wondering if anyone else has heard this, its pretty loud and constant, but comes and off. The dealer said it could be the timing idler, but I thought I'd ask around before I got into that. I'll disconnect the belts and try to rule a few things out soon. Not that many miles on the SC so in my mind that rules out it needing a rebuild, but new oil maybe? However, I was under the impressoin you don't change the oil. Oh its the 2nd gen sc, black housing. Help me out guys.

-Pete