Best rebuild spec for a 4.0 Rover v8?

[RobXjcoupe]

Without going for extra cc, what would be a good spec to re-build a 4.0 Rover v8 engine?
It will be fitted to a Range Rover classic auto but I think the TVR guys will have a perfect spec
No turbo or supercharging just n/a please

[RobXjcoupe]

Thank you for a reply.
I appreciate an auto Range Rover isn't a TVR. It's just the TVR v8 builders seem a little more inventive with the possible mods and engine building side of things.
So just re-build a factory engine with a cam and timing gear. Imagine if a Rover v8 TVR was so simple
No worries was just curious

[RobXjcoupe]

That did cross my mind, a home made overfinch conversion. Originals are expensive to buy

[RobXjcoupe]

phazed said:

Ideally.

4.6 engine for the additional torque.
4.0 pistons for higher comp.
Typhoon cam
72mm plenum
Decent induction
A pair of 421 manifolds and a decaf.

Give you 275bhp and close to 300 torque.

Add some nice heads and you'll see 300bhp.

Maybe a diy MS to run it all but not essential.

Hey now we are talking. I'm on a 92 j reg so no cat restrictions to worry about.
Thank you.

[RobXjcoupe]

DonkeyApple said:

RobXjcoupe said:

Without going for extra cc, what would be a good spec to re-build a 4.0 Rover v8 engine?
It will be fitted to a Range Rover classic auto but I think the TVR guys will have a perfect spec
No turbo or supercharging just n/a please

If you want your RR to go slower than before then fit a TVR engine.

You've a two tonne lump being powered via a 4 speed slush pump with a lock-up set at 50mph and an operating RPM range of 2,300 to 3,500 for almost all your driving. The standard cam delivers the torque where it is needed and how. Start moving the torque curve up or down and start trading torque for BHP and your massive lump of metal will get slower.

A 3.5 EFi RR will out drag a RR with a 4.0 TVR lump. And will ps off the bloke who just wasted ££££s

You can eek a bit more power by ditching the old electrics etc. But for anything significant you need to drop in a 4.6 set up to P38 spec or a super charger.

So to keep a 4.0 and a bit more grunt a supercharger is best or a standard build 4.6 from a p38?
I like the auto slush box rather than a manual conversion and I never even considered where the engine torque should be for the auto to work best.
So a fresh standard 4.6 is really best then?

[RobXjcoupe]

phazed said:

A 4.6 drives that much better than the 4.0, agreed.

If you are starting from scratch I still reckon that the specification I gave above would drive very well and certainly quicker.

I had this in my Chim and it had plenty of mid range and would rev nicely if necessary.

I have had a few 4.0 Discoverys and they were smooth but fairly gutless.

What you need in your Range Rover is my 5.5.

Your spec sounded good I thought for a 4.6. Easily obtainable parts, not too frightening trying to explain to insurance and relativly standard looking when looking under the bonnet.
Would solid lifters and adjustable pushrods be required for the cam you mentioned and would standard 4.6 rods and crank be ok to use?

[RobXjcoupe]

Cheers guys for the valuable input. So at the mo, a mild tune 4.6 seems to be the flavour as it gives a bit more urge but I get to keep my standard running gear without any issues.
My original 3.9 block would be redundant. Can my 3.9 heads be used on the later 4.0/4.6 block together with the 3.9 injection system and then a re-map?