[E34] M60B30 3.0 Optimal air intake.

[632 Regal]

I miss spoke, meant the 5HP18 in the 530. I know the 5hp530 can handle more but want to keep the light weight 5hp18 if i Can.

[Frank87]

I miss spoke, meant the 5HP18 in the 530. I know the 5hp530 can handle more but want to keep the light weight 5hp18 if i Can.

I have also checked this out for the 5HP18 but upgrading this box in a similar way is not feasible. The drums are too small and a V8 version is already stacked close to clearance. In addition, 2 drums are made of aluminium and always show wear on the teeth from the clutch plates. This means these drums can actually not handle the 310Nm torque max.. Even if you increase clutch strength, the limiting factor here is those 2 soft drums.

A 5HP24 would be a great upgrade for any M60B30 also because it shifts better due to not having a brakeband. However the 5HP24 is a real OBD transmission and probably won't work in an E34.

I do not yet have the knowledge HOW a gearbox program works and if you can in someway reverse engineer and map it like you can with engine computers.

5HP30 on a 4.0 harness is the way to go. That extra weight is no factor to me. Less cargo and lose some weight yourself.

[632 Regal]

I have also checked this out for the 5HP18 but upgrading this box in a similar way is not feasible. The drums are too small and a V8 version is already stacked close to clearance. In addition, 2 drums are made of aluminium and always show wear on the teeth from the clutch plates. This means these drums can actually not handle the 310Nm torque max.. Even if you increase clutch strength, the limiting factor here is those 2 soft drums.

A 5HP24 would be a great upgrade for any M60B30 also because it shifts better due to not having a brakeband. However the 5HP24 is a real OBD transmission and probably won't work in an E34.

I do not yet have the knowledge HOW a gearbox program works and if you can in someway reverse engineer and map it like you can with engine computers.

5HP30 on a 4.0 harness is the way to go. That extra weight is no factor to me. Less cargo and lose some weight yourself.

But the hp30 requires the 210 driveshaft, differential, output shafts, brake hardware. A spare 540 is crucial (which I have).

[Frank87]

But the hp30 requires the 210 driveshaft, differential, output shafts, brake hardware. A spare 540 is crucial (which I have).

Just a modified shaft will do. You will increase your highway RPM because the 5HP18 has a longer 5th but this is not a major problem. Diff / brakes / shafts can stay the same provided you do not increase engine power too much.

Just out of interest I have calculated how I would attempt to improve a 5HP18.

I know this box was used on the E36 M3 delivering 350Nm. This means the 5HP18 hard parts can handle 350Nm. The E36 may run on higher pressure, this I do not know.

See this picture:
https://i.imgur.com/kHNPQr9.png

You see in the top left the clutches, thickness of ONE STEEL PLATE, the total steel stack of the original clutch and the total steel stack of the pack how I would make it. It also explains how many steels i'd modify and in what way. You see the steel volume is higher in the tuned (upper right table) situation meaning you have more heat absorption capacity on the pack BUT you need to put the NON SHAVED STEEL PLATES in the MIDDLE of the pack where the most heat is generated.

The table on the bottom left shows you the total pack size old to modified new. Keep in mind that you add 1 steel and 1 friction per pack. The snap profit is the possible gain from using thinner snap rings. This is based on assuming your box is somewhere in the middle of the snap ring table per clutch. Taking the thinnest snap ring nets you the mm shown in the snap profit. The total pack thickness of the new pack with shaved steels has the snap profit subtracted. This is your total size. The snap profit is "invisible" and not actually there but this is a way to compare the total size to the end play of the ZF repair manual.

The bottom right table shows you the final comparison. The old stack is the total of steels + friction OEM situation. The new stack is the increased clutch pack with shaved steals and corrected with snap ring gain. The "increase" column shows the final net. increase of the pack that will carry towards end play.

Shaving off more steel is possible as long as you do not go under the original values and you keep at least 2 or 3 steels of the original diameter to put in the middle of the clutch pack. The ideal situation gives you an increase of the pack that is within the end play. In this case you can use the original end play numbers.

I do not know how far you can go on that endplay. I do not know the effect of a tighter clutch pack.

In this situation the problem is clutch C having a 1,6mm total increase on a window of only 0,3 clearance.

This case still needs some thinking but if you keep the pressure identical you may even get away with shaving 0,2 off the end plate. Those end plates are REALLY thick.

I would want to know what would happen if you put all the endplay on 1mm and clutch D on 1,5mm.

Clutch B is not important at all as this is reverse only. You can even keep this one original.