Agreed.Hey Vlad, you have a tiktok correct? Don't mind me. I just stalk people
PROMO Guru Autowerks - ZF 6HP26/28 Transmission Adapter
- Thread starter GuruAutowerks
- Start date
-
- Tags
- featured
Yeah, i’m not the brightest BMW guy out there but I’m learning
https://vm.tiktok.com/TTPdh2nJUk/
Finally got the kit on mikes car, had a few hurdles to jump through with coding as it was a little different
to the USA models I guess but its all running with no errors.
Took it for a few laps around the block and the hp28 is nice and smooth and the kit is an engineering marvel.
Still need to load up the custom tcu tune as the shift points are set to low and it changes gear as its starts to build boost.
Cant wait to take it roll racing, this thing is going to hurt some ego's.
to the USA models I guess but its all running with no errors.
Took it for a few laps around the block and the hp28 is nice and smooth and the kit is an engineering marvel.
Still need to load up the custom tcu tune as the shift points are set to low and it changes gear as its starts to build boost.
Cant wait to take it roll racing, this thing is going to hurt some ego's.
Well Xmas and a bout of Covid got in the way, but the 135 ST is going really well with the Guru 6hp28 Adapter Kit.
A car ferry today back to MAD Auto Developments with Marty, and the low km 6hp28 seems to be a great choice for all the mods on the car. Feels strong and smooth thanks to the coding by Marty, hard to find a more switched on guy for our E-series.
Guru has done such a great job with this kit and if you are sitting on the fence, don't, couldn't ask for better back up and customer service despite being on the other side of the planet. Kudos Josh, thanks. Rod Stuphin has the custom tune ready to drop in after such short notice that the car was ready to start. MAD will be finalising some of the last tweaks on the car.
Advan Performance did the spanner work beautifully, big shout out to Adam and his team in Auburn, Sydney. My 6hp28 has the old 6hp21 valve body and a 6hp26 TCU from Guru. Trans was converted back to M-Shift from E-Shift so there are some scavenged parts from the 21. Guru might have some M-Shift parts to help out those that don't want to strip their 21 but not sure if he managed to get these hard to find items from ZF.
Thanks again to Josh, Adam, Marty and Rod.
Almost time to annoy V8Bait again.
I thought you needed to use a HP28 TC? You said the Guru adapter bolted to the HP21 TQ?
Yes, but I thought you had a to use a HP28 torque converter. The post said he used his HP21 Torque converter.
OK, I thought that you had to get the HP28 TC as well. I have a fairly fresh TC. So the HP21 TC goes into the HP28 transmission? I thought it wouldn't fit because of the input shaft? I am still contemplating just doing a welded bell housing. Mainly because I have:
(1) A spare HP19/21 housing sitting on the side of my house.
(2) A spare N54 engine block sitting on a stand that I can test fit things on.
(3) A freind who is an expert welder with 20+ years experience.
it would then be called 6hp28
take a pic of the number where can be find on the left side of the transmission.
All i'm going to say if your thinking about getting a zf6hp28 stop and get it, this kit is phenomenal.
I finally ironed the bugs out of this install and it's flawless.
The only thing I would change is the two bottom allen head bolts in the gearbox crossmember to button head bolts as they stick out to far
and vibrate against the factory alloy crossmember on heavy acceleration, it has about 5mm of clearance but it's not enough in high powered applications and sounds really bad and we thought there was something wrong with it.
I had to loosen the gearbox crossmember bolts and adjust it all the way towards the back of the car with the slack in the holes but even then its not quite enough considering how much the factory bushes flex.
Car is ready to hit the drag strip to test this gearbox out and see how it holds up, but it's as smooth as butter so far.
I finally ironed the bugs out of this install and it's flawless.
The only thing I would change is the two bottom allen head bolts in the gearbox crossmember to button head bolts as they stick out to far
and vibrate against the factory alloy crossmember on heavy acceleration, it has about 5mm of clearance but it's not enough in high powered applications and sounds really bad and we thought there was something wrong with it.
I had to loosen the gearbox crossmember bolts and adjust it all the way towards the back of the car with the slack in the holes but even then its not quite enough considering how much the factory bushes flex.
Car is ready to hit the drag strip to test this gearbox out and see how it holds up, but it's as smooth as butter so far.
Last edited:
I am thinking of getting it. I just have spent sooo much money already. My freind offered to put my 500 mile frictions into the dud "race" transmission I bought that had garbage in the pan. I really am too trusting sometimes. Anyway that would be a free route except fluids and my back breaking labor. I just know if it doesn't work out I am back at doing the HP28 swap. I really don't want to swap transmissions more than 1 more time and I know the HP28 is the better way to go but the cost is expensive.
What kind of bugs did you have to iron out?
The only issue he had with this kit was the bad vibration due to the two bottom bolts on the support bracket that was supplied with this kit which is nothing and easily swapped out with button head bolts.
The bugs where not due to the kit but modify the host of custom parts fitted to this car that needed fitnessing to make everything work and not rub or vibrate.
I still haven't changed the bolts due to the bolt supplier not being open on weekends.
We are heading to the drags this week to run some logs and put down a mph and possibly a time if traction is not an issue.
The bugs where not due to the kit but modify the host of custom parts fitted to this car that needed fitnessing to make everything work and not rub or vibrate.
I still haven't changed the bolts due to the bolt supplier not being open on weekends.
We are heading to the drags this week to run some logs and put down a mph and possibly a time if traction is not an issue.
Massive congratulations to you and Marty for being the first kit successfully installed in Australia!
Yall made quick work of converting from E-Shift to M-Shift and dealing with the other minor issues like unknown fitment with RHD Bottom mount turbo etc.
You are both true Gentlemen and Scholars, working on the process providing support and chatting has been a joy.
I look forward to hearing some long term feedback after the car is dialed in with the new setup.
Thank you for the kind words and supporting the project from very early on!
No telling what the future holds but we are exploring several other adapter options.
If you have suggestions on a certain application you want to bring to my attention feel free to message me and I will look into it.
To answer your question concerning the limit of the stock transmission I think there are many factors that play a roll; overall condition, driving/racing style and maintenance/cooling being big ones.
That said based on what we know now most people start seeing slipping issues with the stock 6HP21 around 25 PSI or 600lb-ft TQ.
No doubt some make more with no issues and some make less with issues but in that area is a good general estimate.
Vast majority of all our customers are within this power range and have had built or several stock 6HP21s that couldnt take it.
The stock 6HP21 honestly does very well for what we ask of it, most are pushing it nearly double or more what the factory TQ rating is.
The #1 thing to keep any transmission alive is to manage the heat, run good fluid, stay on top of maintenance items and keep an eye on your Clutch Adaption Values.
Yes 6HP21 and 6HP28 torque converters are interchangeable, our TC adapter comes with the option to run either.
I wouldnt blame you at all for wanting to cut/weld a bellhousing and going that route.
I originally planned to do the same thing as I think many have thought about doing ever since it was originally done by George @GEP Tuning.
All I would say is heat distortion is very real and make sure everything is perfectly true AFTER welding.
Best of luck though I am not here to hate on people who want to do it there own way and make 1 off setups themselves.
We are all just people and I came very close to be one of the people going down that path.
Appreciate that constructive feedback, its the first I have heard of it but know exactly what area youre talking about from your description.
We use low profile allen bolts there but will look into something even lower such as a regular hex or button allen.
Our prototype car was running on 80A poly mounts so maybe thats why we never noticed it and youre right though factory mounts flex more.
I will do some checking with other customers to see if it has been an issue with their setups so we can send out some lower profile bolts to all customers that need them.
For anyone reading those bolts are M10-1.5 x 30mm.
Last edited:
12.2@128mph with a 2.2 60ft on the very first tune and not ideal, this car wasnt built for drag racing but it will be a killer
roll racing car as the turbo is just to big to get off the line quickly.
I installed the reflex last week and waiting for a boost sensor and a new tune to start dialing it all in.
roll racing car as the turbo is just to big to get off the line quickly.
I installed the reflex last week and waiting for a boost sensor and a new tune to start dialing it all in.
Similar threads
