Thread: installing a 4.6

IMO you need to change the cam because there's no provision on the P38 cam for a distributor drive! You also need a spacer to allow the front pulley to bolt up, the crankshaft is longer. Using the P38 ECU means using the coil packs, driving the auto trans, BECM, all the fun stuff in electronics. No go.

Funny thing, today's job is bolting a reco 4.6 top hat linered short motor (Triumph Rover Spares, $5500) into a 3.9 Rangie, I am using all the 3.9 accessories to make it run, ie dissy, manifold, ECU. as it is on gas 99% of the time the fuelling should be OK.

When installing a 4.6 into a range why do people change cams and all the top stuff, Why dont people leave it alone and use the 4.6 ECU.

All Rover V8s are "backward compatable', BUT you cannot use a 4.6 cam if you choose to use the front /timing case off an older engine as it doesn't have a dizzy drive.
It is very difficult to use a 38A ECU in an earlier car as it is integrated with the BECM and the instrument cluster and the ignition switch/key. The ECU has security including sachets of fluid inside which burst if it is opened. I do not know of anyone who has been successful in mating the two.

So that is why most people choose to use the 14CUX ECU with the earlier front . It is much easier to do so, and most people in any case buy an engine short if new and maybe long if second hand (brave people) , and already have all the earlier bits.
BTW the heads are exactly the same so there is no penalty for using them. if you choos e achev with injection, you will still have to integrate the VSS and other sensors which may have different signals, but there is much more known and more specilaists using chev V8s. The Marks site has all the stuff necessary to fit a gen111 , but you have to upgrade the auto for about 8k or so .
Regards Philip A

The biggest plus for using the 4.6 compared to a Chev is no need for an engineers report, and bolts straight in, no adaptors. Camshafts, lifters and timing chain are dirt cheap compared to a conversion kit! Ive seen a couple of 4.6's carbied

Originally Posted by nat p

Hay all,!!
My brother is debeating whether to install a 4.6 from a 1998 HSE P38. OR go the Chev 350/carb later efi route.

When installing a 4.6 into a range why do people change cams and all the top stuff, Why dont people leave it alone and use the 4.6 ECU. Thoughts?

Its a matter of fun V cash. and the Chev is winning so far.

Cheers NAT P

It might be OK for you Mexicans - a 4.6 in a Classic in NSW needs engineering as it's over the 15% increase in capacity rule.

I dont know about RTA, but Vicroads wouldnt know if it was 3.5, 3.9, or 4.6 unless you told them! Maybe you should try that! Although most of them know a P76 from a Rover motor, coz they cant find the engine number on them

Originally Posted by Scouse

It might be OK for you Mexicans - a 4.6 in a Classic in NSW needs engineering as it's over the 15% increase in capacity rule.

I have an 88 RRC with a 4.6 in it, on LPG, 600 holley carb jetted to suit.

It craps all over a 3.9 but don't expect a powerhouse.
2 tonne vehicle without passengers.

Remember a 4.6 is only about the equivalent of a ford baby 289 V8

P.S on petrol only, a holley 470 is ideal for a 4.6 with a carby set up, they are designed for off road and angles.
The holley 600 is a street carby & doesn't like steep hills, kinda floods cause the floats move with the angle of the vehicle, i use LPG off road with no probs