Rover p6 v8 gearbox change

Rover p6 v8 gearbox change

Author
Discussion

llohcins

Original Poster:

32 posts

168 months

Sunday 11th May 2014
quotequote all
Hi all,

I have a rover p6 v8 on the way, purchased from ebay and it comes with an auto box. I am hoping to remove this and replace with a manual 5 speed lt77 from an sd1. Has anyone done this? And if so is there anything I need to be aware of?

It will actually finally be put into my mgb. I have read that a nice combination is a 3.9 cam, the heads from the sd1 and possibly a holly carb. Obviously I'm looking to inject a bit of power.

Thanks in advance

tonys

1,080 posts

223 months

Sunday 1st June 2014
quotequote all
If no joy on PH, try this forum, very useful for P6 information:

http://www.classicroverforum.net/

nickramsey

2 posts

118 months

Saturday 14th June 2014
quotequote all
Hi, if you insist on changing a perfectly good car, be prepared to change the tunnel and carpets inside the car. It involves the electrics, reversing light etc. Also mountings & rubbers for the gearbox.
You will need to alter and have rebalanced the propshaft.

Some people will change the back axle, a massive job, to get higher gearing for higher top speed
The front brakes will have to be uprated, as per the police versions of the P6B, to handle the extra torque and speed!

The rear cart springs held on only by a flimsy cotton reel type rubber bush, will not be able to handle the extra speed and tension. You will need to uprate the rear shock absorbers as well.
It will probably need a rear torsion bar similar to a jaguar.

Also the rear brakes would benefit by being changed to the range rover disc brake system, to avoid going round in circles when braking hard.
You will also need to use the brake pressure,rear brake compensator valve,from the range rover, to balance the brakes correctly, to stop that happening.

The power steering is too light as it is, so you would need to change it to the ford granada unit to make it less sensitive at higher speeds.

Have fun!!??






tr7v8

7,192 posts

228 months

Saturday 14th June 2014
quotequote all
nickramsey said:
Hi, if you insist on changing a perfectly good car, be prepared to change the tunnel and carpets inside the car. It involves the electrics, reversing light etc. Also mountings & rubbers for the gearbox.
You will need to alter and have rebalanced the propshaft.

Some people will change the back axle, a massive job, to get higher gearing for higher top speed
The front brakes will have to be uprated, as per the police versions of the P6B, to handle the extra torque and speed!

The rear cart springs held on only by a flimsy cotton reel type rubber bush, will not be able to handle the extra speed and tension. You will need to uprate the rear shock absorbers as well.
It will probably need a rear torsion bar similar to a jaguar.

Also the rear brakes would benefit by being changed to the range rover disc brake system, to avoid going round in circles when braking hard.
You will also need to use the brake pressure,rear brake compensator valve,from the range rover, to balance the brakes correctly, to stop that happening.

The power steering is too light as it is, so you would need to change it to the ford granada unit to make it less sensitive at higher speeds.

Have fun!!??
One of us is very confused as he's putting it in a MGB so which MG has Power steering? Jaguars don't have torsion bar rears, P6Bs don't have leaf springs?????

tr7v8

7,192 posts

228 months

Saturday 14th June 2014
quotequote all
llohcins said:
Hi all,

I have a rover p6 v8 on the way, purchased from ebay and it comes with an auto box. I am hoping to remove this and replace with a manual 5 speed lt77 from an sd1. Has anyone done this? And if so is there anything I need to be aware of?

It will actually finally be put into my mgb. I have read that a nice combination is a 3.9 cam, the heads from the sd1 and possibly a holly carb. Obviously I'm looking to inject a bit of power.

Thanks in advance
Plenty of after market cams for the RV8, SD1 heads are no different to RR heads. I assume it is a high compression engine 10.5 : 1 if it is an original one. You may need an octane improver for this. Not sure in an MGB but I suspect you'll need a Offy 360 manifold to keep the height down & the Carter/Edelbrock/Webber 500 is a much better fit for a mild RV8 than the Holley & easier to set up.
This build was a defender V8 with heads skimmed 1mm, a Rovercraft 266 Deg Cam, Offy 360 inlet, Edelbrock 500. Went quite well in a TR7 V8


Stephen Davies

1 posts

109 months

Monday 9th March 2015
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Have you still got the old gearbox .?

llohcins

Original Poster:

32 posts

168 months

Saturday 9th May 2015
quotequote all
Thanks for all the replies. After a bit more research and an old engineer friend popping by I think I'm fairly sorted. I have some sd1 Viennese heads which have bigger valves, will go for a piper cam probably and a 3.9 crank. The gearbox connection is reasonably straight forward.

I do still have the p6 auto box and a standard 1.8 mgb one.

The fitting should be fairly straight forward (touch wood) with only a tiny bit of tunnel cutting. I will probably end up with a slightly modified bonnet so that it all fits plus the exhaust manifold from an rv8 so a bit of engine bay cutting and re strengthening.

Should be fun. The rear crossmember can stay standard for the time being so I'm sure I'll be spinning the rears all over the place but that sounds great as well. I'm not looking for an every day car but one to have a blast about in and hopefully the p6 engine will give me the fun injection that I need.

Thanks for taking the time to reply, I didn't get any notifications of replies so sorry for my delay in response.