Thread: Is Bigger Really Better?

Is Bigger Really Better?

I am reliably informed here that it is ......

Originally Posted by vnx205

I've heard the argument that there is no substitute for cubic inches and I have read an enormous number of posts on this forum by people who are convinced that Land Rovers need bigger engines. However I remain unconvinced.

Surely a bigger, more powerful engine will probably be heavier and if the same level of reliability is to be maintained won't most of the transmission components need to be stronger and therefore heavier? That means the suspension will need to be stronger and heavier and the chassis will need to be stronger and heavier. Before you know it, your Land Rover has turned into a Hummer.

I always though that part of the reason my Series III was so capable offroad was that it weighed only a bit over 1600kg and was lighter than a Hilux 10 years ago.

<snip>.

And my old 1974 Jeep CJ6 had a 232 cu in straight six and the entire driveline was much heavier duty than a Series Rover.
It also tared out at 1375kg and weighed in over the weighbridge, including all fluids, steel hardtop and bullbar at just on 1600kg.

I see how you are approaching this, but it isn't necessarily the case.

There is little weight difference between the 4.6 and the 3.5, likewise it would be interesting to know the difference in weight between the V8 and the Series 2.25. I doubt much. The chassis is strong, like strong and will deal with a hell of a lot more power than what people put through them. The gearboxs also have reserve, the typical ZF 4HP22 takes up to abut 380Nm and the ZF4HP24 up to about 480Nm, but the old Torqueflite's apprently are good for high powered drag cars that are running ***well*** beyond that of any LandRover motor. The Salisbury diff is completely oversized and under half shafted but is more than strong enough, even the Rover axles can have a lot of power put through them as seen with the Bowlers etc, they just don't like to be shocked, especially if standard.

Especially with improved technology and materials and also aftermarket supplier, I don't belive that a lean mean powerful machine is a misleading notion.

I may be wrong about this but ... I think the V8 is actually lighter than a 2.25, (at around 375lb) because the V8 is aluminium, whereas the 2.25 (at around 450lb) is cast iron. Has anyone got any idea if this is right?

Originally Posted by Slunnie

I see how you are approaching this, but it isn't necessarily the case.

There is little weight difference between the 4.6 and the 3.5, likewise it would be interesting to know the difference in weight between the V8 and the Series 2.25. I doubt much. The chassis is strong, like strong and will deal with a hell of a lot more power than what people put through them. The gearboxs also have reserve, the typical ZF 4HP22 takes up to abut 380Nm and the ZF4HP24 up to about 480Nm, but the old Torqueflite's apprently are good for high powered drag cars that are running ***well*** beyond that of any LandRover motor. The Salisbury diff is completely oversized and under half shafted but is more than strong enough, even the Rover axles can have a lot of power put through them as seen with the Bowlers etc, they just don't like to be shocked, especially if standard.

Especially with improved technology and materials and also aftermarket supplier, I don't belive that a lean mean powerful machine is a misleading notion.

The only experience I've had is with 3.5 rovers and P76 engines, my 77 2 door went much better with the P76 in all conditions except for steep inclines due to the holley fitted. Towing was great because it had lots of torque, as was soft sand driving because it had plenty of torque to keep the wheels turning, although sometimes this just meant you dug in deeper, whereas the 3.5 would just run out of puff. The above were matched to the LT95, however with my fathers P76 powered rangie with the torqueflight just doesn't have the same output as the auto sucks too much from the engine.

1st low with the early LT95's with a P76 is next to useless on road

My current rebuild 3.9 goes very nicely although I haven't been through soft sand to be able to compare but would imagine it would be similar as it has a higher than standard compression and torque cam fitted - I asked one of our regular mechanics how it compared to other 3.9's - he thought it was a 4.6

At the end of the day it probably comes down to how healthy your engine is and in terms of breaking drive line I think driving styles has a lot to do with it as well as correct maintenance.

Originally Posted by Panda

I may be wrong about this but ... I think the V8 is actually lighter than a 2.25, (at around 375lb) because the V8 is aluminium, whereas the 2.25 (at around 450lb) is cast iron. Has anyone got any idea if this is right?

Ahhh, god bless Terriann
Power specs for engines commonly used in Series Land Rover engine conversion


LR 2.25 4cyl - 450lbs
LR 2.6 6cyl - approx 600lbs
LR 3.5 V8 - 318lbs (wiki has this at 375lb)
LR Isuzu 3.9 - 711lbs

full cast iron Chev 350 - 575lbs, the more alloy then the lighter it got
LS1 - 450lbs

Bloody hell, didn't realise there was such a difference between the 2.25 & the 2.6! And to think the SIII does so well hauling all that weight.

Originally Posted by Slunnie

Ahhh, god bless Terriann
Power specs for engines commonly used in Series Land Rover engine conversion


LR 2.25 4cyl - 450lbs
LR 2.6 6cyl - approx 600lbs
LR 3.5 V8 - 318lbs (wiki has this at 375lb)
LR Isuzu 3.9 - 711lbs

full cast iron Chev 350 - 575lbs, the more alloy then the lighter it got

Originally Posted by Panda

Bloody hell, didn't realise there was such a difference between the 2.25 & the 2.6! And to think the SIII does so well hauling all that weight.

What is surprising is the weight difference between the 6 and the full iron Chev.