3.9 Vs 3.5?

Well the 3.9 ive bought ahs done about 130,000 miles and has always been run on petrol so should be ok.....should be!

Ill get it checked out properly before i do anything then but looks like the 3.9 might be the way to go!

Wont give up onh the 3.5 though, may as well get it running sweet, no point in letting a perfectly good engine go to waste!

I may well be wrong wrong but also thinking of doing a 3.5 v8 rebuild on carbs and have been told that fitting a 3.9 cam is a cheap mans way of uprating a 3.5 engine?

Please correct me if im wrong as advice can vastly vary!?

the cracking behind liner is effected by heat ,if you over heat or nearly it can crack depending on your blocks original manufacture 3.9 is the same block as 3.5 but with 200 thou bored out leaving thinner ali bore to push liner in with 3-4 thou interferrence fit ,some are bored more central than others leaving weak point usualy near head bolt hole,liners sit on ledge so cant slip unless catastrophic seizure,or crack relieves pressure on linerleaving it relatively loose,i have 3.9 in my disco been no trouble in that way but had 2 that cracked before,3.5 high compression with 3.9 cam and 3.9 hotwire system (the later 3.5 had this anyhow )is the way to go for bullet proof engine,maybe not win races but how far to go the more power you can get the less reliable it becomes,in the long term

You can also stoke a 3.5 to 4.3L(?) which makes for a very torquey lump although I doubt it would take kindly to excessive revs. 'Real Steel' used to do a conversion kit.

norseman said:

You can also stoke a 3.5 to 4.3L(?) which makes for a very torquey lump although I doubt it would take kindly to excessive revs. 'Real Steel' used to do a conversion kit.

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V8 tuner do one also. the 86.26mm Stroke makes a 3.9 into a 4.8

norseman said:

I don't doubt it, but surely if you want your power at high revs you don't buy a 2 tonne 4x4 in the first place - esp. one with a slush-box

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Better keep an eye out for mine then very quick! updated engine and transmission and suspension and brakes beats most newer range rover and other makes off the line ask fett he has had a run in it my company specialises in uprated performance, upgrades for all Lr models including diesels
Just as perspective one of my customers has a updated rocketsled engine in a D2 manual get 24 mpg on a run
My classic does 22 mpg on a run 2 less and a auto!