Blew up 340i (HP50) Transmission

SC_B5X · 12-04-2020, 04:29 AM

Went to do some 0-60 and 1/4 times tonight and blew up the transmission (ZF8HP50) in my 340i. My main course of action now is doing a HP70 swap into the 340i out of a 535d. I will be fully documenting the swap and posting it here on F30Post as well as B58 Enthusiasts Facebook page. Luckily another user here has already done the swap and also documented it decently well (https://f30.bimmerpost.com/forums/sh....php?t=1663852).

Mods: Pure800, Dorch Stage 2 HPFP, VRSF 4.5" Downpipe, Remus Axleback, Wedge E50 MHD Tune (29psi Boost / 18° Timing).

Estimated Power: 650-680whp.
60-130 Time: 6.76s

View post on imgur.com

Glemm1970 · 12-04-2020, 06:47 AM

It turns out that the 8hp50 limit is 26/27 psi for the Pure800 and GC.

StannisBaratheon · 12-04-2020, 09:23 AM

What exactly happened to the HP50? Did you actually get it to disassemble itself while driving, or did it burn through the clutches?

BMWILUVU · 12-04-2020, 09:49 AM

It looks like a big project with the car out of action for a time.

cfm56d7b · 12-04-2020, 10:01 AM

What an interesting project. Is the replacement transmission new or used?

SC_B5X · 12-04-2020, 08:31 PM

Quote:

Originally Posted by StannisBaratheon

What exactly happened to the HP50? Did you actually get it to disassemble itself while driving, or did it burn through the clutches?

Guessing clutches are shot.

Quote:

Originally Posted by BMWILUVU

It looks like a big project with the car out of action for a time.

Should have it up and running by next week.

Quote:

Originally Posted by cfm56d7b

What an interesting project. Is the replacement transmission new or used?

Going to be buying it used. Found one with very low miles (8k miles).

B58togo · 12-04-2020, 10:16 PM

We play and we pay. It was a good death.

harkes · 12-05-2020, 09:51 AM

Sorry to hear about the failure. Limited torque in 3rd and 6th or full send?

Must be at double the rated torque with those numbers.

Jay5k · 12-05-2020, 04:32 PM

Quote:

Originally Posted by Glemm1970

It turns out that the 8hp50 limit is 26/27 psi for the Pure800 and GC.

The Pure800 will make more power than the GC on 27psi though right? I plan to run 26psi and 28psi max boost on my GC once my dorch stg2 arrives.

Lego864 · 12-05-2020, 11:32 PM

Quote:

Originally Posted by Jay5k

The Pure800 will make more power than the GC on 27psi though right? I plan to run 26psi and 28psi max boost on my GC once my dorch stg2 arrives.

Maxed out GC appears to be high 500s - low 600s. Pure800 at 28psi with decent timing (e50 will support) should be well into mid 600s at least. GC should be more than safe.

Andre was pushing at least high 700s - low 800s for a while on stock zf8hp50 before his went out. Seems Michael just has really bad luck with his car lol. (Jk man, appreciate you pushing the limits! )

G.Newt · 12-06-2020, 02:32 AM

Was a Pure tranny not an option? B58 King had his trans upgraded by Pure Drivetrain Solutions, cuz mans was pushing 800+ lb-ft lol.

SC_B5X · 12-06-2020, 02:40 AM

Quote:

Originally Posted by Lego864

Maxed out GC appears to be high 500s - low 600s. Pure800 at 28psi with decent timing (e50 will support) should be well into mid 600s at least. GC should be more than safe.

Andre was pushing at least high 700s - low 800s for a while on stock zf8hp50 before his went out. Seems Michael just has really bad luck with his car lol. (Jk man, appreciate you pushing the limits! )

I take no offense to this, my luck is awful and half my drivetrain is LKQ parts now

Quote:

Originally Posted by G.Newt

Was a Pure tranny not an option? B58 King had his trans upgraded by Pure Drivetrain Solutions, cuz mans was pushing 800+ lb-ft lol.

Even with the discount they offered me it's still more than i'm willing to spend right now. HP70 should be more than adequate for the time being.

zeenon53 · 12-06-2020, 02:10 PM

I have a new transmission cooking right now, should have more info by the end of the week. Plenty of shops that already build zf for hellcats are getting into the supra market now.

TheFanatic · 12-07-2020, 08:30 AM

now I know the 70 is built to handle more power than the 50 but if there is no tune for the 70 wouldn't you be running the same risk? You'll definitely be well over stock power levels for the 70 and have slower shift times than a tuned 50.

chaungo · 12-07-2020, 09:53 AM

Quote:

Originally Posted by Lego864

Maxed out GC appears to be high 500s - low 600s. Pure800 at 28psi with decent timing (e50 will support) should be well into mid 600s at least. GC should be more than safe.

Andre was pushing at least high 700s - low 800s for a while on stock zf8hp50 before his went out. Seems Michael just has really bad luck with his car lol. (Jk man, appreciate you pushing the limits! )

Andre also just recently blew up his GC LOL. I believe it cost him a 20k pot race unfortunately, hopefully VTT pays the lost

Alan340 · 12-08-2020, 09:49 AM

Quote:

Originally Posted by chaungo

Andre also just recently blew up his GC LOL. I believe it cost him a 20k pot race unfortunately, hopefully VTT pays the lost

*GC+ he had the big boy. Vargas did give him that turbo for testing purposes mainly to push it to the limit and find out its max potential.

///Madgreek1 · 12-08-2020, 01:17 PM

My transmission is still hanging in there, but has anyone else snapped a diff bolt? Im on my 3rd one...

When I say snapped, yes I literally mean sheared right at the diff/mount point.

For reference im running 340i FBO w/ GC currently, dyno 572tq

TheFanatic · 12-08-2020, 01:23 PM

Quote:

Originally Posted by ///Madgreek1

My transmission is still hanging in there, but has anyone else snapped a diff bolt? Im on my 3rd one...

When I say snapped, yes I literally mean sheared right at the diff/mount point.

For reference im running 340i FBO w/ GC currently, dyno 572tq

Not a common problem from what I've heard. You doing some hard launches on a regular basis? What conditions are you in where the bolt breaks?

///Madgreek1 · 12-08-2020, 02:22 PM

Quote:

Originally Posted by TheFanatic

Not a common problem from what I've heard. You doing some hard launches on a regular basis? What conditions are you in where the bolt breaks?

Not really. Both breaks have been under normal driving, however I do use my powerband to its fullest on a semi regular basis.

SC_B5X · 12-08-2020, 05:03 PM

Quote:

Originally Posted by TheFanatic

now I know the 70 is built to handle more power than the 50 but if there is no tune for the 70 wouldn't you be running the same risk? You'll definitely be well over stock power levels for the 70 and have slower shift times than a tuned 50.

XHP has since been made available since the last HP70 swap writeup was done.

Hkilla00 · 12-08-2020, 07:01 PM

29 psi of boost I wouldn't do a dig and even if I would I'd be in 2nd at least. I'm on 32 psi and break loose in 2nd all the time I try to stay away from 1-2nd gear pulls because you already know the trans will break

TheFanatic · 12-08-2020, 08:04 PM

Quote:

Originally Posted by SC_B5X

XHP has since been made available since the last HP70 swap writeup was done.

Ah, I didn't know that, thanks for telling me

12-04-2020, 04:29 AM	#1
SC_B5X Second Lieutenant 339 Rep 261 Posts Drives: 2016 BMW 340i Join Date: May 2019 Location: Greenville, SC iTrader: (0)	Blew up 340i (HP50) Transmission Went to do some 0-60 and 1/4 times tonight and blew up the transmission (ZF8HP50) in my 340i. My main course of action now is doing a HP70 swap into the 340i out of a 535d. I will be fully documenting the swap and posting it here on F30Post as well as B58 Enthusiasts Facebook page. Luckily another user here has already done the swap and also documented it decently well (https://f30.bimmerpost.com/forums/sh....php?t=1663852). Mods: Pure800, Dorch Stage 2 HPFP, VRSF 4.5" Downpipe, Remus Axleback, Wedge E50 MHD Tune (29psi Boost / 18° Timing). Estimated Power: 650-680whp. 60-130 Time: 6.76s View post on imgur.com __________________ Instagram: SC_B5X 2016 BMW 340i M-Sport Pkg Pure 800 Turbo, Dorch Engineering Stage 2 HPFP, VRSF 4.5" Downpipe, Remus Axleback, CTS Turbo Intake, 8HP70 Transmission Swap w/ XHP Stage 3 Trans Tune, and Custom E50 Wedge MHD Tune
	Appreciate 3 Supr3me467.00 kern4173239.50 JD1193799.50 Tweet Quote

12-04-2020, 06:47 AM	#2
Glemm1970 Private First Class 147 Rep 151 Posts Drives: BMW M140IX. Join Date: Apr 2020 Location: Vladivostok iTrader: (0)	It turns out that the 8hp50 limit is 26/27 psi for the Pure800 and GC. __________________ M140IX. Turbo VTT GС,Flash Wedge Steven. xHP stage 3. CSF. Dorch 2. 100ron+30%E85,+WMI. 1620kg. 1/4ml 10.50s. 100/200 5.91s +8C.
	Appreciate 0 Quote

12-04-2020, 09:23 AM	#3
StannisBaratheon Private 14 Rep 73 Posts Drives: 2016 340i Xdrive Join Date: Aug 2019 Location: Earth iTrader: (0)	What exactly happened to the HP50? Did you actually get it to disassemble itself while driving, or did it burn through the clutches?
	Appreciate 0 Quote

12-04-2020, 09:49 AM	#4
BMWILUVU Major 421 Rep 1,009 Posts Drives: 340ix Join Date: Mar 2017 Location: The Boibs iTrader: (0)	It looks like a big project with the car out of action for a time.
	Appreciate 1 sspade1901.50 Quote

12-04-2020, 10:01 AM	#5
cfm56d7b Major General 2637 Rep 6,342 Posts Drives: 2017 440i Gran Coupe & 2015 X5 Join Date: Nov 2012 Location: Orange County, CA iTrader: (2)	What an interesting project. Is the replacement transmission new or used?
	Appreciate 0 Quote

12-04-2020, 10:16 PM	#7
B58togo Major 720 Rep 1,232 Posts Drives: M240i Join Date: Feb 2017 Location: NY iTrader: (0)	We play and we pay. It was a good death. __________________ 2017 M240i AW/ ZF8/ BM3 E40 Johnson tuned/ Dorch Stg.1 HPFP/ xHP Stage 3/ ER catless DP/ Remus axle back/ BMS intake/ M Performance LSD 11.6 @ 122 mph
	Appreciate 4 Supr3me467.00 SC_B5X338.50 Wires654.00 f32spaceship666.50 Quote

12-05-2020, 09:51 AM	#8
harkes Colonel 860 Rep 2,045 Posts Drives: M135i, NSX and AE86 Join Date: Apr 2014 Location: Xiamen, China iTrader: (0)	Sorry to hear about the failure. Limited torque in 3rd and 6th or full send? Must be at double the rated torque with those numbers. __________________ M135i 8AT PWG, MHD, Pure Stage2, WMI via Torqbyte CM5-LT, Custom tuned by PureBoost (A Dane in China)
	Appreciate 0 Quote

12-06-2020, 02:32 AM	#11
G.Newt Captain 299 Rep 658 Posts Drives: 340i xDrive 6-Speed Join Date: Feb 2017 Location: Denver, CO iTrader: (0)	Was a Pure tranny not an option? B58 King had his trans upgraded by Pure Drivetrain Solutions, cuz mans was pushing 800+ lb-ft lol. __________________ 2016 340i xDrive 6-speed. FBO. Stage 2 E30 BM3. 440hp / 515lb-ft (Mustang Dyno)
	Appreciate 0 Quote

12-06-2020, 02:10 PM	#13
zeenon53 Major 28 Rep 1,120 Posts Drives: BMW Join Date: Apr 2010 Location: obx iTrader: (3)	I have a new transmission cooking right now, should have more info by the end of the week. Plenty of shops that already build zf for hellcats are getting into the supra market now.
	Appreciate 1 G.Newt298.50 Quote

12-07-2020, 08:30 AM	#14
TheFanatic Private First Class 49 Rep 154 Posts Drives: BMW 340i Join Date: May 2020 Location: Wisconsin iTrader: (0)	now I know the 70 is built to handle more power than the 50 but if there is no tune for the 70 wouldn't you be running the same risk? You'll definitely be well over stock power levels for the 70 and have slower shift times than a tuned 50.
	Appreciate 0 Quote

12-08-2020, 01:17 PM	#17
///Madgreek1 Private First Class 84 Rep 175 Posts Drives: BMW 340i Join Date: Nov 2019 Location: Tacoma, Wa iTrader: (0)	My transmission is still hanging in there, but has anyone else snapped a diff bolt? Im on my 3rd one... When I say snapped, yes I literally mean sheared right at the diff/mount point. For reference im running 340i FBO w/ GC currently, dyno 572tq
	Appreciate 0 Quote

12-08-2020, 07:01 PM	#21
Hkilla00 Private 12 Rep 78 Posts Drives: Bmw 340i Join Date: Mar 2020 Location: Tdot iTrader: (0)	29 psi of boost I wouldn't do a dig and even if I would I'd be in 2nd at least. I'm on 32 psi and break loose in 2nd all the time I try to stay away from 1-2nd gear pulls because you already know the trans will break
	Appreciate 0 Quote

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