Increasing the ability to transmit more torque

[mra-minis]

I can be contacted on [e-mail]

What modifications can you do to the AP1 & 2 to raise its torque capacity ?

1) Upgrade to the AP2
2) Upgrade to a 1275 Metro or SPi Mini (Includes the variant with the MPI engine)
3) Upgrade to 3 plate forward clutch pack
4) Upgrade to 3 plate top & reverse clutch pack
5) Upgrade the friction materials
6) Increase the line pressure from the oil pump
7) Fit Timken type idler gear set (SC only at the moment)
8) Increase the shift point, this is the point at which the transmission up-shifts on kick down
9) Modify the stall speed of the converter to allow the use of wider duration camshafts, a race cam has a wider duration.
10) convert the auxiliary pump to flow oil to the VB for a higher flow rate and quicker shifting.
11) fit wider bands to 2nd and 3rd gears
12) ..........

[notamini]

When you say increase oil pressue where to and how does this help? Right now my cold oil pressure is so high it causes leaking at the filter housing. Engine pressure is about 76 psi.

Can the stall speed be changed easily for the converter and adjustable both up or down? Can it be adjusted to slip better at idle?

[mra-minis]

Nov 14, 2020 12:58:43 GMT notamini said:

When you say increase oil pressue where to and how does this help? Right now my cold oil pressure is so high it causes leaking at the filter housing. Engine pressure is about 76 psi.

Can the stall speed be changed easily for the converter and adjustable both up or down? Can it be adjusted to slip better at idle?

I can be contacted on [e-mail]


The oil pressure I am talking about is the "line pressure" this is the pressure the transmission sees, and you would need to fix a gauge to the filter head to get this reading, 76 when cold for an engine isn't so bad, but what have you got when its warmed up ?

I suspect your filter housing is a little damaged, which end is it leaking from ?

The stall speed can be changed easily enough but not in a garage environment it really needs specialist equipment to realign and balance but also to maintain the correct running clearances within the converter. Yes it can be adjusted both ways, although rarely would anyone want to reduce the stall speed, it's normally raised to allow for wider duration camshaft (racier engine)

If your stall speed is too low on a standard engine then suspect the main stator bush failure, this is often seen as a stall speed just above tickover causing the transmission to "crash" into gear from rest, when driving it doesn't matter so much, but this can destroy your transmission in much the same way as a jack hammer destroys concrete.