i installed a sonnax shift kit in my 98 part #HP-4L60E-01 along with both servos and i like the shift better, then the transgo and servos in my 94.

 

Here's the deal...

I actually have the Transgo HD-2 kit installed. Yes, the trans has to be dropped for a full install. Technically you can skip this step and only modify the valve body, but it's highly recommended you install the COMPLETE kit, not half-*** it or you may regret it in the future.

That being said, if you want harder shifts, the Transgo HD-2 kit is NOT the kit you should be interested in. The HD-2 kit is a reprogramming kit. It fixes issues with the valve body and accumulators. Honestly, there is very little difference in shift feel before and after the HD-2 kit. Yes, the shifts are a little faster and crisper, but it is not that big of a difference. The 1-2 shift is only slightly firmer than before and the 3-4 shift actually feels a little softer. The biggest difference was in the 2-3 shift with is consistently crisp and decently firm compared to what it was. Also, the torque converter engages much more firmly with the HD-2 kit installed. In reality, you can't even tell the car has a shift kit because it's barely firmer and faster than stock. I'm the only person that knows it's in there because no one can tell.

If you are looking to increase the life if your transmission, the HD-2 kit is a great idea. If you are looking for slightly faster and slightly firmer shifts, the HD-2 kit is a good idea. If you are looking for tire-barking shifts, the HD-2 kit is the last kit you should be looking for. I can't chirp gears in my car. I never could, not before and not after the HD-2 kit was installed.

It cost $180 to install the kit. Prices will vary, so I recommend you get a quote before you get it installed, and make sure it's by a reputable guy that knows his way around a 4L60E and has installed plenty of reprogramming kits in the past. Most shops will quote you $150-$200 for a complete install.

 

You might want to get your tuner to bump up the line pressure some if you're not happy with the results. The HD-2 kit made a big difference in making the shifts quicker and firmer especially on my 4L80E. Prior to installing the shift kit, I got together with Frost and he tried several different changes to adjust shift quality (that had been very successful on the 60 btw). It made little to no effect on the 80, so I installed the shift kit to see if mechanical changes would help as opposed to just programming. It made a huge difference. I met up with Frost again and he made some tweaks to get it where I wanted.

Mine is actually so firm that going around corners at part throttle, it will chirp the tires when it goes into 2nd. This is with a 3600 stall too, and I could have had it firmed up even more if I wanted!

The one thing I would recommend if you have an aftermarket stall is to follow all of the options for the firmest shifts possible in the instructions.

 

interesting that i read this. not to thread hijack, i think this will help the op as well.

what is the difference between the two, i hear you saying the HD2 is better. which one does the ws6 store sell?

http://www.ws6project.com/user_stor/...oducts_id=1809

http://www.summitracing.com/parts/TR...2/?image=large

 

Transgo HD2 worked fine untill I have a race trans put in later on..

 

Another vote for TransGO

 

I drive a 94' Z28 LT1 and I drove the car for a year with 100K clocked, and it chirped 2nd no problem. Even after a leaking cooler line, and a trans that went dry enough to go into limp mode and I was still driving it hard and street raced it a few times. It still chirped 2nd.

I installed a TransGo HD2 shift kit last weekend, and it made a world of difference. 2nd is very firm, and if exiting a turn at 2500rpm and going into 2nd, the tail will nudge out.

Acceleration is a lot more efficient and consistent, and I am shifting at 6000RPM. My car is stock apart from an SLP exhaust set up at the back and no cats or muffler anywhere else, stock manifolds.

For those who said you have to lower the trans, you do not have to move it a mm from its position. The servos can have the new springs installed with the trans up in place. 1 shim is all you need and I know, the pistons won't go in far enough to install the snap ring. Just use the wooden end of a hammer (mine has a rubber cover on it as well) and push against the servo cover using the wooden end, and the transmission well as a pivot point. Have a friend slide the snap ring in. Its a little annoying, but it will get it. Make sure it seats in correctly. Also, try to use a very short flat screw driver to push the snap ring into the groove.

You will have a few annoying valves in the valve body which you will have to remove, just use your imagination and some good tools with help.

Just follow the steps from TransGo. They are forward and simple. Do not pay 200 to anyone to do such a simple job.

Use vaseline to hold the check ***** in place and to lube up new O-rings.

It took me 4 hours over 2 days to do it. That includes bringing the valve body home and re-valving it. And replacing the booster valve in the pump with that annoying sir clip lol trust me, its good fun and you will learn about your trans in the process. Also, we had a few breaks every once in a while.

The only thing that you cannot replace is the set of springs that go inside the transmission because the trans is not apart. Just keep them, when and if you do toast your trans, they are there for the rebuild

Ask anything you want about this kit, you do it once, you learn it forever

 

At the bottom of this thread I posted the directions. Just read over it.
https://ls1tech.com/forums/automatic...l#post11868412
I advise against using vasaline. A small tub of trans gel is just as cheap but made for transmissions. Yeah vasaline will work but you run a risk. Trans gel will dissolve in atf at room temp.

If you don't move the trans down some to install the servo, I hope the underside of your car is clean enough to eat off of. All it takes is little trash to take the whole thing down.

 

He can use trans gel if he can get a tub of it. I did not have any at the moment, so I just used Vaseline as a substitute.

Again, you do not NEED to lower the transmission to do the servos.

If you are worried about getting muck and crap into the trans, clean the surrounding area with some contact cleaner (the best muck remover) or carb-cleaner. You could use kerosene and a brush but the smell will drive you nutts!

Again, get some tools and have some fun. Good luck with that annoying sir-clip holding the boost valve, its going to be the most fun you will ever have.

Get some sir-clip pliers, Stanley makes a type with interchangeable heads

 

I don't believe in changing line pressure. That's nothing but a recipe for disaster. I've talked to enough trans builders and tuners to know that these transmissions were designed to operate within a certain line pressure. In fact, the point of the vacuum modulator is to remove the spikes in line pressure electronic controls cause as those spikes can lead to disaster. Even the strongest-build units out there are recommended to run with stock line pressure, and too much line pressure can easily fry even the toughest units out there. The idea behind installing the HD-2 kit is to strengthen the tranny and correct errors in the design for reliability's sake. Changing the line pressure will do nothing but take away that reliability, defeating the purpose of the shift kit altogether.

That being said, the 4L80E is a whole different animal than a 4L60E. It's easy to make a 4L80E rattle your teeth. You can put shift kits in a 4L80E that'll make it shift harder on a reasonable setting than you could ever do with a 4L60E throwing the line pressure through the roof, messing with the accumulators and all those tricks to make it shift harder and in the process ruin the unit. Making a 4L80E chirp the tires during a shift is like changing an air filter. It's that easy.

 

You are misunderstanding line pressure changes in the context of his post. There factory has a cap on pressure in the PCM and I don't TOUCH IT. Neither do the other tuners who know what they are doing (in most cases). With that said, it's not like you just get 1 set pressure, there is a curve that builds pressure against a calculated delivered tq variable that is continuously updated. This curve can be tailored all day long without raising max line pressure or making any physical adjustments that jack the pressure the up across the board. I have never seen a setup yet that works best with OEM programming, and certainly not something that is performance oriented.

Also the assertion that the 80 slams around... Except for the fully built units, this has not been my experience at ALL. The stock units shift very lazily and they NEED mechanical parts (along with tuning) to work optimally. It's not like that for the 60.

 

B&M are good also

 

I understood what he said. I don't want the part-throttle line pressure changed, either. The reason why is because I don't think there is a soul on this Earth that can say exactly what the "best" line pressure is at each RPM. I know that the stock line pressure settings work, and I don't trust bumping the pressure up. Raising the line pressure part-throttle ensures that every single shift the transmission ever makes is harder, and that has to eventually wear out the transmission. Yes, I'd like it to shift a little firmer than it does, but I can deal with what I have.

All I said is that it's much easier with a few tricks to make a 4L80E shift harder than a 4L60E, and a 4L80E can be set up to shift much harder than a 4L60E could ever dream of. I don't think I'm wrong.