BMW Transmissions on SR20's - Page 4 - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

SE-Rawkus · 03-19-2021, 04:13 PM

The gear ratios from the F80 (M3/M4):
1. 4.806
2. 2.593
3. 1.701
4. 1.277
5. 1.000
6. 0.844
7. 0.671

I?m pairing it with a Q45 (3.54) diff.

RalliartRsX · 03-19-2021, 07:56 PM

So 1st would be useless with a 3.92....or anything shorter than a 3.43 or something. 6 and 7 would be an overdrive regardless. The rest seem to fall in line with the cd009 ratio

Yellow4g63 · 03-20-2021, 11:45 PM

Quote:

Originally Posted by RalliartRsX

You need to also consider gear ratio. There's a good chance the dct with 7 gears have enough as a different gear spread where going with a 3.9 or similar will literally deem the first 3 gears useless.

Wow that sucks. Now I have to do some gear ratio calculations.

PoorMans180SX · 03-21-2021, 09:04 AM

Quote:

Originally Posted by brndck

z33 auto is 3.3 iirc.
if you want taller, y34 is 3.1

also FYI normal 2way LSD does not fit z33 auto diff, since the ring gear is offset compared to manual trans z33 diff. OS Giken does make a LSD that fits z33 auto, but afaik kaaz and most other diff manufacturers do not offer one that fits z33 auto diff.

Nissan Pathfinder rear diffs are 3.13.
Nissan Armada/QX56 rear diffs vary came in 3.36 and 2.94 ratios as well.

gills · 03-21-2021, 09:50 AM

Or, add 1000 rpm to your engine speed

Yellow4g63 · 03-21-2021, 05:00 PM

E9x M3 DCT Gear Ratios E92 V8

1st - 4.780
2nd - 3.056
3rd - 2.153
4th - 1.678
5th - 1.390
6th - 1.203
7th - 1.000

with a 3.33 auto final drive on 255/40-17 tires

8500RPM 39.77 62.2 88.29 113.28 136.7 158.01 190.08
RPM 1st 2nd 3rd 4th 5th 6th 7th

with the 3.54 same tires
8500RPM 37.41 58.51 83.05 106.56 128.64 148.64 178.81
1st 2nd 3rd 4th 5th 6th 7th

With a 3.13
8500RPM 42.31 66.18 93.93 120.52 145.49 168.11 202.23
1st 2nd 3rd 4th 5th 6th 7th

Can't format it right for the forum

thom · 07-11-2021, 11:33 AM

Hi guys,

I just finished with this swap which took me maybe more than 1 month since i did everything all alone at my parking spot .

Parts i purchased:

GS6-53DZ gearbox
Pmc gearbox adapter plate + flywheel
Pmc chassis mount shifter
Flex plate from auto sr20
Sachs oem clutch
Gearbox seals

Everything else was custom made by me. ( except the driveshaft)

Process i can say was pretty straight forward but i had some issues ( i still have).

The spot

Adapter plate on . I believe no one has mentioned that now you can't remove starter without having to remove the gearbox.

Gearbox on .

Took me maybe half an hour to align and install it , most difficult part was to put the damn gearbox on the floor jack.

Then when raising it i realized that the gearbox touches the firewall.

Removing it and bang the firewall was not an option so i placed some small pieces of wood between the firewall and the gearbox and started to raise it slowly and carefully .

You could hear the 30 year old metal bend very easily.

Didnt really need a lot to be honest.

Also the 2 top gearbox allen bolts took me i don't even now how many hours since there was absolutely no space to put any tool and torque them down.

After that it was time for the gearbox mount which may look super ugly but i believe it does the job.

Ugly also but stiff selector rod. This one i may order it to be cnc cut because i dont believe its welded 100% straight .

For shifter i chose the shortest option that was available because i dont really like those long ones.

For driveshaft i used the original one with adding a 3 bolt flange and i didnt use the bmw rubber coupling. I didnt take a photo of that.

After installing everything and thinking i am done , the real nightmare begins.

Clutch bleeding = impossible.

Clutch would only engage half and gears didnt go in. Pedal would start to feel stiff only after 40% of the total travel.

I then changed the slave cylinder which was new and thought maybe its defective, and also removed the rubber clutch line and made a stainless steel one.

Did manage to bleed the system , no air coming out all, but still the pedal didnt have the best feel.

The last option that did the job( still not 100%) was to adjust the master cylinder rod that goes on the pedal so it pushes a little more fluid on the system.

I believe the problem is the clutch bearing position and clutch is not pushed 100%.

Pmc says to use the 28.5mm but in my situation i think the 33mm position would work better?
I have emailed them but no reply so i dont know.

Anyway today was the first ride which didnt go as planned and i need your opinion- help.

Gearbox makes a terrible sound which i did notice when i first started the car when was on jack stands and thought it will go away when i install the driveshaft etc.

https://www.youtube.com/watch?v=pf_VHvrCMiM

When driving its sounds very bad when decelerating with gear in.

Any help would be appreciated.

*update*

Looks like i'm experiencing harsh gearset rattle on deceleration, and certain RPM's where the engine NVH is at its worst. After doing some research it seems that some people have this issue after installing lightweight single mass flywheels in their bmw's.

I assume having no rubber guibos on the driveshaft , in combination with how rigidly I have the transmission mounted to the chassis is going to cause some unwanted NVH from the GS6-53dz transmission.

Bmw guys suggest changing the fluid , a mix of 75w140 with atf which i wait to be delivered and see how it goes. Also i think to remove the polybush gear mount and put some normal rubber mounts .

Haven't push the car yet since im trying to break in the clutch and figure out these noises but in general gearbox feels amazing. The gear changes are so smooth.

The only issue is that its very short because i have a 4.36 diff. 1st gear is like it doesnt exist , i dont even use it.

I'll put the old 3.9 crown wheel i have next week and i hope it will be better.

03-21-2021, 09:50 AM	#95
gills Zilvia Junkie Join Date: Dec 2012 Location: Long Island, NY Posts: 449 Trader Rating: (13) Feedback Score: 13 reviews	Or, add 1000 rpm to your engine speed __________________ IG: core4motorsports www.core4motorsports.com

03-21-2021, 05:00 PM	#96
Yellow4g63 Zilvia FREAK! Join Date: Jan 2003 Location: Socal Posts: 1,451 Trader Rating: (5) Feedback Score: 5 reviews	E9x M3 DCT Gear Ratios E92 V8 1st - 4.780 2nd - 3.056 3rd - 2.153 4th - 1.678 5th - 1.390 6th - 1.203 7th - 1.000 with a 3.33 auto final drive on 255/40-17 tires 8500RPM 39.77 62.2 88.29 113.28 136.7 158.01 190.08 RPM 1st 2nd 3rd 4th 5th 6th 7th with the 3.54 same tires 8500RPM 37.41 58.51 83.05 106.56 128.64 148.64 178.81 1st 2nd 3rd 4th 5th 6th 7th With a 3.13 8500RPM 42.31 66.18 93.93 120.52 145.49 168.11 202.23 1st 2nd 3rd 4th 5th 6th 7th Can't format it right for the forum __________________ 95 240sx RB20 415whp 91 Nx2000 VVL yo

07-11-2021, 11:33 AM	#97
thom Join Date: Jan 2018 Location: Greece Posts: 17 Trader Rating: (0) Feedback Score: 0 reviews	Hi guys, I just finished with this swap which took me maybe more than 1 month since i did everything all alone at my parking spot . Parts i purchased: GS6-53DZ gearbox Pmc gearbox adapter plate + flywheel Pmc chassis mount shifter Flex plate from auto sr20 Sachs oem clutch Gearbox seals Everything else was custom made by me. ( except the driveshaft) Process i can say was pretty straight forward but i had some issues ( i still have). The spot Adapter plate on . I believe no one has mentioned that now you can't remove starter without having to remove the gearbox. Gearbox on . Took me maybe half an hour to align and install it , most difficult part was to put the damn gearbox on the floor jack. Then when raising it i realized that the gearbox touches the firewall. Removing it and bang the firewall was not an option so i placed some small pieces of wood between the firewall and the gearbox and started to raise it slowly and carefully . You could hear the 30 year old metal bend very easily. Didnt really need a lot to be honest. Also the 2 top gearbox allen bolts took me i don't even now how many hours since there was absolutely no space to put any tool and torque them down. After that it was time for the gearbox mount which may look super ugly but i believe it does the job. Ugly also but stiff selector rod. This one i may order it to be cnc cut because i dont believe its welded 100% straight . For shifter i chose the shortest option that was available because i dont really like those long ones. For driveshaft i used the original one with adding a 3 bolt flange and i didnt use the bmw rubber coupling. I didnt take a photo of that. After installing everything and thinking i am done , the real nightmare begins. Clutch bleeding = impossible. Clutch would only engage half and gears didnt go in. Pedal would start to feel stiff only after 40% of the total travel. I then changed the slave cylinder which was new and thought maybe its defective, and also removed the rubber clutch line and made a stainless steel one. Did manage to bleed the system , no air coming out all, but still the pedal didnt have the best feel. The last option that did the job( still not 100%) was to adjust the master cylinder rod that goes on the pedal so it pushes a little more fluid on the system. I believe the problem is the clutch bearing position and clutch is not pushed 100%. Pmc says to use the 28.5mm but in my situation i think the 33mm position would work better? I have emailed them but no reply so i dont know. Anyway today was the first ride which didnt go as planned and i need your opinion- help. Gearbox makes a terrible sound which i did notice when i first started the car when was on jack stands and thought it will go away when i install the driveshaft etc. https://www.youtube.com/watch?v=pf_VHvrCMiM When driving its sounds very bad when decelerating with gear in. Any help would be appreciated. update Looks like i'm experiencing harsh gearset rattle on deceleration, and certain RPM's where the engine NVH is at its worst. After doing some research it seems that some people have this issue after installing lightweight single mass flywheels in their bmw's. I assume having no rubber guibos on the driveshaft , in combination with how rigidly I have the transmission mounted to the chassis is going to cause some unwanted NVH from the GS6-53dz transmission. Bmw guys suggest changing the fluid , a mix of 75w140 with atf which i wait to be delivered and see how it goes. Also i think to remove the polybush gear mount and put some normal rubber mounts . Haven't push the car yet since im trying to break in the clutch and figure out these noises but in general gearbox feels amazing. The gear changes are so smooth. The only issue is that its very short because i have a 4.36 diff. 1st gear is like it doesnt exist , i dont even use it. I'll put the old 3.9 crown wheel i have next week and i hope it will be better. __________________ Last edited by thom; 07-17-2021 at 03:31 AM..

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03-19-2021, 04:13 PM	#91
SE-Rawkus Join Date: Jan 2015 Location: Miami Posts: 32 Trader Rating: (3) Feedback Score: 3 reviews	The gear ratios from the F80 (M3/M4): 1. 4.806 2. 2.593 3. 1.701 4. 1.277 5. 1.000 6. 0.844 7. 0.671 I?m pairing it with a Q45 (3.54) diff.

03-19-2021, 07:56 PM	#92
RalliartRsX Post Whore! Join Date: Apr 2006 Location: Maryland Posts: 4,753 Trader Rating: (32) Feedback Score: 32 reviews	So 1st would be useless with a 3.92....or anything shorter than a 3.43 or something. 6 and 7 would be an overdrive regardless. The rest seem to fall in line with the cd009 ratio