View Single Post
#1: 04-16-2011, 12:58 PM
Valve Body Mods, Giant Leaps Forward!!!
ClimberD@HexMods's Avatar
Title: 5EAT 101
Location: Dallas, TX
Posts: 6,733
iTrader: (72)
Send a private message to ClimberD@HexMods Find all posts by ClimberD@HexMods Reply With Quote
I am opening up shop!

Hexagram Modifications, aka HexMods, is now taking pre-orders for the HexMods Valve Body Modification line's first release, the F1!

Welcome to the HexMods F1 Package (F1 because your transmission will "finally" shift fast), for the 2005-07 LegacyGT and OutbackXT 5EAT (5-speed Electronic Automatic Transmission), using the TransGo shift kit many people have been talking about. The HexMods F1 produces faster shift times and more shift firmness under acceleration, while preserving reasonable shift comfort during low-throttle shifts. The HexMods F1 is all your healthy transmission needs to handle significantly increased power and torque output. No longer is the $4000+ transmission race build required for most big-power setups!

Hexmods F1 Service:
$500, which includes a $25 return shipping credit via UPS Ground, and Paypal fees. Faster return shipping upgrades such as Overnight or 2-Day are available for an additional charge.

How do I get my Valve Body modified by Hexagram Modifications to become a HexMods F1?

Remove your valve body from your transmission, box it up, and ship it to Hexagram Modifications in Dallas, TX.

Once received, the valve body will be cleaned, disassembled, cleaned again, upgraded with new valve control springs, valves, check balls and larger fluid passageways, reassembled, and packaged back up, all within 24 hours.

Then you re-install the valve body in your car, add back in ATF, and give the TCU (Transmission Computer) 100-400miles to learn the new valve body (it will act very weird at first).

Then you modify your car's power output to your heart's content, and rest assured that your transmission can handle whatever you throw at it!

How to Remove and Install the Valve Body into the transmission?
To drain and fill ATF properly.
To remove and install the Transmission Pan and Valve Body.

Install Notes to make your life easier:
-8mm hex socket / allen key for ATF drain plug.
-10mm socket and extension for everything else!
-Electric Drill with socket adapter will really speed things up.
-Always have a big drain/drip pan handy to catch all the fluid. When you think it's done, you will loosen another VB bolt and it will start raining again. It will drip forever, don't be in a rush.
-You do not always need to replace the drain plug gasket, but assess on a case-by-case basis. If you are missing a gasket, add one. 18mm copper crush washer or regular copper washer is all you need.
-All bolt torque specs should be respected. Most important is that they are all even. Don't over tighten!
-Whether working on removing the transmission pan or valve body, loosen all bolts but do not at first remove them. This gives the pan or valve body a few millimeters to separate from its respected mating surface. For the pan, this trick will allow you to avoid ATF splash city (the drain plug does not drain all ATF from the pan. For the valve body, this allows the VB to decouple from the transmission, allowing yet more fluid to come out.
-Separating the pan from the transmission after the bolts are loosened/removed is a pain because the silicone/RTV gasket has glued it on. Use a plastic trim tool to wedge the pan off the transmission.
-When the pan is off, you will see leftover gasket on the transmission machined mating surface, and on the pan. Use a drill and wire wheel to knock off the gasket material from the pan. PICTURE Use a razor blade to shave the gasket material from the trans mating surface.
-Use Brake Cleaner to clean up the pan and pan magnet thoroughly.
-The VB is held in by 2 different lengths of bolts. Just be cognizant of this and reference the attached/linked PDFs when reinstalling.
-The VB is heavy. If you can get a jack with pad under it, that may make your life a little easier for uninstalling or re-installing it.
-Remember to line up the shift position rod with the transmission shift position cylinder when you are installing the new VB in the transmission. It will make sense when you see it.
-For pan re-installation, I recommend Permatex Right Stuff Gasket, because it dries in a few minutes, and is easy to apply. Put on a ring around the pan, lining the INSIDE (not outside) of each bolt hole. Less is more, unless you use too little

First and last, use common sense.
Please PM or post any questions.

Valve Body Packaging Instructions:
  1. Put valve body in plastic trash bag to prevent leaking of fluid. Double bag just to be sure.
  2. Wrap VB in A LOT OF soft foam sheets and/or bubble wrap. The most important part to protect is the top of the valve body with all the wires and solenoids. Put extra foam and padding on top of that area, and on the side with the plastic and wires. Pad sufficiently such that the VB is insulated from blunt force impacts and getting dropped on the pavement.
  3. Place in a box that is sufficiently filled with padding such that there is no room for anything to bounce around. More is better.
  4. Mark as Fragile if available.
  5. Private Message me with your PayPal email address, and I will invoice you and send you shipping instructions.
How much power/torque will my 5EAT be able to handle with a HexMods F1?

No absolute number is known, or can be known. There are too many variables to make a reliable power/torque claim. So much depends upon the torque converter's response to your power setup. The torque converter magnifies torque especially at lower RPM. This means an early-spooling Stage 2 Legacy and a late-spooling Stage 4 GT35r Legacy could produce a comparable threat to the longevity of a transmission, even though the GT35r produces monster power when compared to a Stage 2 Legacy. This example takes into consideration that the TCU (Transmission Computer) is programmed to apply a certain amount of clamping power per variables such as RPM and MPH. The GT35r may make a ton more power, but the TCU is conveniently programmed to apply more line pressure through the big turbo's high RPM area of operation.

I estimate the HexMods F1 able to handle any Stage 2 setup, as well as any Stage 3 / Stage 4 setup up to 350wtq (all wheel torque), as referenced by what a comparably-setup 5MT Legacy would produce. It can probably handle a lot more, but there is simply not enough hard information to know how 5eats behave at that power level.

Will a valve body modification help or improve a partially worn out or slipping transmission?

NO! If you have a transmission with some clutch pack wear due to abuse, improper care and maintenance, high mileage, or excessive engine torque output (from engine modifications), then at best a modified valve body will marginally extend the life of the transmission. However, it could make a slipping condition worse, and could make problematic shifting worse. If you have a worn transmission, consider a rebuild in addition to a valve body modification. If you are not sure whether your transmission is worn, seek the assessment of a local transmission expert. Note that the TCU is designed to learn around wearing transmission clutches, such that it can hide the feeling of wear that might be more evident without computer learning. With engines as with transmissions, you can only do so much to diagnose an internal wear condition without removing it and opening it up.

How does the HexMods F1 compare to IPT's Valve Body Modification?

To be strictly objective, IPT charges a higher price, and makes a much fewer number of physical modifications to the valve body. In terms of transmission shift behavior, the HexMods F1 changes gear ratios faster and firmer than IPT's modification. Neither modification significantly compromises shift comfort at low loads.

__________________________________________________ __________________________________________________ _________________________

Original Write-up:


A few of you know I have been spending almost all my free time working on my transmission, specifically my valve body collection. I'm the type of person who seeks to dissect a complicated mechanism down to its most basic elements, at least when I have the information available to comprehend what I am looking at.

A couple things had been bugging me about our valve body modification options:
1) IPT valve body service, only shop in town, charges $769 + 2x shipping, and says nothing about what they do. They had been performing their service awfully quick. So either they had nothing else going on in the shop, or it was super easy. So we were all getting taken easy.
2) IPT valve body does not make the shifting as good as it needs to be. Shifts still take a while at high RPM, for instance. Way better than stock, but nothing like what the 350Z clowns describe or show in their videos.
3) The 350Z TransGo shift kit was/is making RE5R05A transmissions shift very very well. But we don't have a TransGo option.
4) One member had his trans shop custom install a 350Z TransGo kit, which he said shifted superior to the IPT valve body mod.


I seek to solve every transmission "problem" found on my 5eat, and I have been busy.

In doing so, I hope to bring to the 5eat community a set of R&D'd shift kit / valve body modification services that are superior to IPT, and are more on par with the 350Z options. I intend to bring these to market at a lower cost than IPT. A win for all of us.

I am aiming to become more of a business entity in the LGT community. I intend to make some money doing this. If I did not intend to make money with providing a service, I would stop investing most of my evenings working on this, and I would do the minimum to accomplish my own shift performance needs, which are almost met. Instead, I aim to develop a valuable service in order to help any 5eat enthusiast achieve the shift performance they need to hold real power. This would include modifying both stock valve bodies and IPT modified valve bodies to achieve proper shift performance across the board for all.


Special thanks to Frank_ster for helping me learn so much about transmissions, and Buick 3.8L motor swaps.
Special thanks to others, you know who you are.


I have figured out exactly what IPT does in their 05-07 LGT 5eat VB mod. One can intuitively figure a similar type of mod is done to many similar transmission valve bodies. I will not get into how I feel about knowing what they have been charging $769 to do all these years. It makes me feel depressed that at one point I was so beholden to the forum group think that I was actually excited to join the ranks and pay IPT good money for their VB mod service. It breaks my heart, and I'm very confused about the whole situation.

I believe I can successfully implement a superior shift kit modification to 08-09 LGT valve bodies as well as 05-07s, but that will come only after 05-07 model years have a working proof of concept.

I have a tester valve body and a TransGo RE5R05A shift kit, and I am investing a lot of my time and energy in working to fully analyze the 350Z TransGo VB modifications. I am well on my way to having an absolutely superior valve body to the IPT valve body.


Now, if you have a 05-09 5eat LGT and are interested in having your valve body modified (some of you for a second time), please post the following information and feel free to ask any questions.

LGT 5eat car year? 05 06 07 08 09
IPT VB mod already performed? Yes or No
Are you willing to pay close to but less than IPT prices (perhaps again) for a proper shift kit modification performed by fellow 5eat performance enthusiast ClimberD himself?
Attached Files
File Type: pdf 2005-2007 5EAT ATF Procedure.pdf (39.0 KB, 1959 views)
File Type: pdf 2005-2007 5EAT Valve Body & Pan Procedure.pdf (91.5 KB, 2779 views)

Last edited by ClimberD@HexMods; 06-20-2011 at 08:42 PM..
Sponsored links