engine & gearbox swap - SDI Vitesse efi

D

Darren

New Member
Would a engine and automatic gearbox from a 1984 sdi 3500 vitesse fit into a 1977 P6 3500 automatic without to much trouble. What modifications would be needed? Is this a good choice or are there better options ? I 'm looking to update the P6.
Look forward to hearing your ideas.
Thanks Darren.
 
Darren
As the resident modification loony I will try to help. I cannot see any problem with your suggested swap, but be aware that you will need to fit the wiring loom from the SD1 to make the EFi work. I cannot off the top of my head remember if the SD1 gearbox is electronic or not, probably not 'cause of the age.
The engine mounts will swap right over, but you may need to fabricate a new gearbox mount, and the shifter may need to be modified or changed.
I have put a 4L EFi from a crashed Discovery into my P6B, mated to a 4 speed ZF auto out of a Jag, but using the Discovery bellhousing. I had to make a new gearbox mount but it was not that hard. Also had to change the shifter to a XJ40 J gate so that I could select all the gears! :p
This has made a huge difference to the old girl and we now bowl alone the highway at 120kph with only 2500 rpm on the tacho! Which reminds me, if the speedo output on the new gearbox is electric instead of a cable thingy, you will be up for a new speedo as well.
Hope that this helps, any questions just message me and I will try and get back to you as work allows!
Cheers
GUY :)
 
A quick note about engine heights.... The earlier SD1 EFI engines have a low plenum chamber (aka air box) on top of the engine which will fit under the bonnet. Later ones have a much taller one which won't. That's a pity as the later arrangement is generally acknowledged to be far superior.

For my taste I wouldn't have EFI. A Weber 500 4 barrel downdraught is a very fine solution and fits a treat. At that point you wonder why your buying the Vitesse set up, especially as the auto box is not much of an improvement on the Borg Warner.

My recommendastion would be SD1 heads, Weber 500 and ZF 4 speed. The latter can be sourced either from LDV ambulances with a cable change (use a Range Rover 3.9 Classic change lever in the car), or a Jag XJ 40 with electric control, Jag J gate change lever and a Range Rover (3.9 Classic or P38) bellhousing. You could tweak the cam to taste, my preference would be an RP4 to retain the torque. Your going to need to put a duplex cam drive on anyway with an HC oil pump (free with every SD1 front cover). While your about it fit a Mallory twin point distributor and electronic booster pack.

Big advantage of this set up is that you get an overdrive top gear ratio with all the same benefits found with the 5 speed manual conversion.

Chris York
 
Hi,
Gone off the vitesse idea. Prefer the two options posted.
Would be happy to go with either, it wil proberly depend
on what parts i can lay my hands on.
I've seen several 4 speed ZF auto gearboxes advertised,
are all ZF 4 speed boxes the same size with different ratios or are they built to differnt dimensions for particular cars.
I think my lack of knowledge could hold this project up.
 
Hi,
Went into the breakers yard today he explained that the gearbox should be easy to get hold of it's the extension
caseing for 2wd that are scarce.
 
Its a fine carb. and works really well but be aware that the Weber makes much more of a V8 'Roar' than EFI or SU's, especially under full throttle. It really makes people stare and scares old grannies!

I have one fitted to my SD1 and it changes the character of the car quite a bit, but I'm sticking with originality all the way with the P6.
 
Darren
To answer your gearbox question, ZF built a standard box that manufacturers would fit their own bellhousing to. The difference in top end speed etc, was acheived by the use of different diff ratios. I have found that the first 3 ratios in the ZF are almost the same as in the BW, but the 4th gear gives an overdrive, I think it is 0.93(?) to 1. I found that the Jag box, since it has a 2wd output works fine, but the prop shaft will need to be shortened by about 3 inches, this is a job for the experts!)
I looked at the Weber carb option for my car, but with EFi I am getting 34mpg on the motorway and 27mpg around town. Not bad for 4.0L! With the price of petrol about to go mad, since it is already $1.10 L here and set to go higher, I will go with the system that gives the best economy, and power ( dyno was 240hp last time I checked).
Hope this helps
Cheers
GUY :)
 
You must log in or register to reply here.
Back
Top