3.9 v 4.2

[muskyman]

I think the bottom end is adequate, who really spins their V8's much past 3k ? I believe ARP makes a stud kit for the Rovers, I am sure you could have the mains cross bolted on a 4.2

I do all the time...rovers love to spin

 

[Maryland 110]

I think v8's sound great wound tight. I regularly rev my tdi past 3k.

 

[Nonimouse]

It's the top ends that suffer from a life of over revving but 5K isn't over revving; especially with good oil and 3k changes

The 4.2 is a lovely engine. Really nice; even though it uses the Devil's fuel

 

[sven]

So, is ECR exaggerating the bottom end of 4.2's?

Absolutely. That article was written a long time ago and I know plenty of 4.2's with near 200k miles and they run perfect.

 

[SeaRubi]

my 4.2 LWB had 230k on the clock and purred like a kitten. that truck is still going strong as far as I know.

the 4.2's bottom end isn't any different than the 3.9. The power bump comes from the revised cam specs in the 4.2 - some folks use the 4.2 cam in a 3.9 to wake it up when putting one back together.

One big advantage to going with the 4.2 is that they can be had for dirt cheap if you find one up for sale. 4.6 cores (especially gem blocks) are costly.

my .02

cheers
-ike

 

[sven]

The power bump comes from the revised cam specs in the 4.2

Yeah and the longer stroke helps a little too.

Somewhere I read that the 4.2 crank was originally intended for a Rover diesel V8 project that never happened.

 

[Viggen]

So, will I have to source an ECU for the 4.2 also or could I do as RPI says and either chip my 3.9 or adjust the pots in the MAF, etc...?

The 4.2 is appealing since it will give me that extra power Im looking for without having to change much in the way of sensors, etc...

 

[Nonimouse]

Yeah and the longer stroke helps a little too.

Somewhere I read that the 4.2 crank was originally intended for a Rover diesel V8 project that never happened.

The 'Iceburg' - the dieselified version of the Rover V8

There were shed loads of blank cranks cast, some were used up for the 4.2, others sold off for scrap! The last batch sold went to Steve Lund the genius V8 builder who was driven mad by aluminium poisoning, drugs and drink. I helped move them into his workshop back in about '03