Thread: BMW N57 8hp to TD5 Auto adapter kit

Originally Posted by Tins

If you're in the Eastern 'burbs last time I was at Nick-a-Part they had 2. Not bare chassis, but maybe picked clean enough for your needs. Just FYI. D2, not 2a.

Thanks Tins, am inner city basically (Travancore is part of the old Flemington) so I take it is the Kilsyth one and not Campbellfield which is just up the road. Family are all out at Croydon and grew up there, so chance to drop in and see them as well.

I need the D2 so this works well.

Tried pick a part but the chassis was too low to the ground for me and my shoulder to get underneath. So went off to Mentone and Landy Place, asked politely if I could and Danny was more than happy to allow me to have a look underneath at D2 V8 up on the hoist, THANKS Danny.

So the bad first, the LT230 support bracket will have to be removed as will the the ACE box and SLS box for installing the 8HP.

as the first two pics will testify, there are plenty of attachment points at these positions to locate the plate.

Absolutely definitive,
the chassis width is 640mm
The chassis height depth is 150mm


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..

Further discussions held regarding the best to install.

1 - get blank plates 500mm * 150mm
2 - remove the 4HP
3 - remove the SLS and ACE boxes on the outside of the chassis
4 - make templates up for the attachment points
5 - drill out the holes, with some play
6 - bolts replaced with high tensile ones to fit the extra depth
7 - fit the plates and install 8HP
8 - tack on supports
9 - remove plates and weld on fully the supports
10 - refit the plates and supports
11 - get the thing running

It may be necessary by the way to have a nut either side of the chassis so between the SLS and ACE mounting them out a fraction

Will provide the template back to the manufacturer for future use and the possibility of making up a guard plate

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It may be two plates on the drivers side rather than one and keeping the LT230 support as a attachment point for the guard, the easier it is to install for others with the possibility of doing it in the driveway, the better.

So hopefully this will be delivered in a couple of weeks, HOPEFULLY and I get this done before my upcoming shoulder op.

Long meeting yesterday with the installer, does Merc restorations for a day job, couple of nice pagodas sitting there as well as other of various vintage, great workshop.


So bit the bullet and ouch, but to get it done expediently some times its worth it. The final assembly with measurements.

CHASSIS UNIT FOR 8hp.jpg

So were in agreeance as to rather than removing the current Lt230 mount, will cut the plate either side and keep the underlip for the cross plate. So the unit will look like this, well sort of the cut out will be closer to the new support bracket.

CHASSIS UNIT FOR 8hp with cutout.jpg

Whilst he thought the best way of doing it was bespoke holes and inner supports in the chassis rails and cant disagree with this at all, want to keep this as easy as possible for others to undertake in their future installs, so the standard holes it will be.

Liked the idea of a nut either side of the chassis to help maintain the structurally rigidity of the ACE and SLS units.

Now have to find the bolt dimensions of these to source.



The console gentleman got back to me and has made up a switch holder to recess the switches down rather than switch tops standing proud on the console


holder for switches.jpg

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Did a complete ratio chart for the 8 speeds utilizing the Ashcroft Calculator, this only has six speeds so had to mock it up.

TD5 8HP - 4.37 diff, 1.003 LT230, 32 inch tyres

Speed/Gear	First	Second	Third	Fourth	Fifth	Sixth	Seventh	Eight
10 KPH	1344	896	602	477	368	286	240	191
20 KPH	2688	1792	1204	954	735	572	480	382
30 KPH	4032	2688	1807	1431	1103	859	721	572
40 KPH		3584	2409	1908	1471	1145	961	763
50 KPH		4480	3011	2385	1839	1431	1201	954
60 KPH			3613	2862	2206	1717	1441	1145
70 KPH			4215	3339	2574	2004	1681	1336
80 KPH			4818	3817	2942	2290	1922	1527
90 KPH				4294	3310	2576	2162	1717
100 KPH				4771	3677	2862	2402	1908
110 KPH					4045	3149	2642	2099
120 KPH					4413	3435	2882	2290
130 KPH					4780	3721	3123	2481

Standard

Speed/Gear	First	Second	Third	Fourth
10 KPH	773	461	312	227
20 KPH	1546	923	623	454
30 KPH	2319	1384	935	681
40 KPH	3092	1845	1247	908
50 KPH	3865	2307	1559	1135
60 KPH	4638	2768	1870	1362
70 KPH		3229	2182	1589
80 KPH		3691	2494	1815
90 KPH		4152	2805	2042
100 KPH		4613	3117	2269
110 KPH		5075	3429	2496
120 KPH			3741	2723
130 KPH			4052	2950

I had noted earlier in this feed that the 8HP gives basically I gear below and one gear above the 4HP, so just for clarity gave some colour and removed all rpm above 5000

No need for 49% low range reduction gearsm you'll have it already.

How will you go pulling 400rpm less on the highway?

Certainly a considerable weigh up in choosing the 1.003, have been checking the operation of the 6hp in the allroad as to how it chooses the ratios and consumption etc at all speeds. Certainly 1st is dismissed so quickly its almost redundant except on quicker takes off. The operation up around 70 and 80kph is 3rd and 4th and then over 80kph, 5th and 6th around the 100kph. Can change up if I desire of course. The top ratio is around 1750rpm at 100kph in the Audi.

On the drive out to the installer yesterday 50k's out of Melbourne, where it was 80 on the city freeway (400 metres down the road), then 100 and finally 110kph and as to how I use the D2, well this is more real world. I get on the freeway and drive for 3-4 hours to the VHC and then 20-30k's along the backroads.

So predominantly the cruising speed is 110kph plus the extra couple which equates to 2100rpm which is where I would imagine it will spend most time in 8th but may downshift up a couple of the hills out of here back to 7th. This without the flare as the TC unlocks in back to 3rd at the moment of course.

As you would appreciate the instant lockup of the transmission is the real game changer, in the allroad it is barely 1-200rpm rise before locking in. So think it will be fine if all I expect it be is a cruising overdrive than expecting it be 95kph + gear. It may operate at 100 plus a couple cruise on the flat and if so this would a pleasant advantage



Just did a 3.54 and 32" tyre with the first three and top three gears of the 8HP as an extra comparison

Speed/Gear	First	Second	Third	Fourth	Fifth	Sixth
10 KPH	1327	884	594	282	237	188
20 KPH	2653	1769	1189	565	474	377
30 KPH	3980	2653	1783	847	711	565
40 KPH	5306	3537	2377	1130	948	753
50 KPH	6633	4422	2972	1412	1185	942
60 KPH	7959	5306	3566	1695	1422	1130
70 KPH	9286	6190	4160	1977	1659	1318
80 KPH	10612	7075	4755	2260	1897	1507
90 KPH	11939	7959	5349	2542	2134	1695
100 KPH	13265	8843	5943	2825	2371	1883
110 KPH	14592	9728	6538	3107	2608	2072
120 KPH	15918	10612	7132	3390	2845	2260
130 KPH	17245	11496	7726	3672	3082	2448

Not too much difference in this at all compared to my set up with the LR 1st giving a more than admirable 55.20:1

Latest Console Design before sign off. Switch assembly will be 7.5cm from the base of the shifter cutout. I may have previously mentioned but the shifter will actually be on an angle of around left 30-45 degrees from the centre line. So when my hand is on the shifter, the direction will be directly away / toward the angle of my arm.

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