v8 Upgrade?

[OTB]

G’day All,
Long time reader, first time writer. I apologise in advance if this information has already been posted – I am still hunting round the site catching up on old posts!
A quick background – I purchased a 1968 Series 2a LWB ute last year as a project and have been chipping away on it ever since. I have replaced a fair amount of gear to date but I am now interested in biting the bullet as the v8 bug has got me.
The ute currently has an old Holden 179 in it with what I assume to be all original running gear and diffs etc... I am not as up to speed on the intricate details as most of you seem to be so I thought it time to send a few queries your way.
My major concern is that the vehicle is very high revving and not the quickest thing on the road. Don’t get me wrong, I am not chasing a fast machine, just something which could do 100km/hr more comfortably. A recent trip north saw me shifting through the 4 gears in no time at all and sitting on 3,500-4,000rpm to attempt to keep with traffic. I estimate an absolute max speed of 80km/hr but given a recent rim and tyre change (33/12.50/R15) I am not certain of the exact speed. Long story short, I managed fuel economy of about 150km per tank and after getting through tank number two, arrangements were made to leave the Landy behind and proceed on the trip with something quicker and more fuel efficient.
So I understand there may be a few options. I understand overdrives can be fitted and alternatives diffs put on to increase road performance. I am at a stage now where I need to decide if I stick to the current engine and running gear I have and fit an overdrive/change diffs, or if I take the lot out and replace it with a suitable v8 option/combination.
Can someone indicate (ballpark) the size and expense of such a job? What will work? What won’t work? I understand the Rover 8s will fit relatively easily? Is there a more reliable 8 that would suit (perhaps a holden 253?).
Keen to hear your thoughts and a big thanks in advance for any help you send my way.
Cheers.

[Blknight.aus]

your going to be digging into a mine field with this one...

the 179 is sort of pushing the limits of the series gearbox and a v8 WILL lunch it.

The easiest solution that maintains the offroadability is to fit up an aftermarket Tcase with a better ratio in high maintaining the low range. a complete engine and box change is not to be undertaken lightly and including purchasing a second hand box/tcase and doing everything yourself I'd be very surprised if you got any change out of $5k.

[NiteMare]

triallers in the UK have been using the Rover 3.5 V8 for a considerable number of years in front of Series boxes and transfer cases without killing them every other weekend along with quite a few road going bitsas but i guess this depends as much on the driver and his compassion for the gearbox (i'd definitely fit one if i could afford the fuel), it is also suggested that a Suffix D gearbox from a 2A is most likely the strongest..

3.5 RV8 conversions can be sat on the original chassis mounts with the gearbox in the standard position using a joining adaptor, custom engine block mounts and a remote oil filter, the rear of the crank "may" need to be slightly modified and a spigot adaptor made up along with possibly the flywheel redrilling for the clutch cover depending on which engine it comes from..

there are some differences with timing covers and water pumps from the various donor cars/rangies/landies/discos making the job more difficult as they "can" push the front of the engine forward reducing the space for the radiator..

it is also usually suggested that you use the largest capacity rad' you can for the RV8 ...

you'll also need to cut the passenger footwell to make room for the lefthand bank

these are only bits of information i've gleaned from the web myself, they're not my own experiences so obviously they're only rough guidelines (i've only worked on getting my mates one back on the road after a 5 year lay up), i'm a 200tdi person, using in front of Series boxes and so far my daily driver (88" bitsa) has taken 2.5 years to kill an already tired suffix A series3 gearbox (it still works but howls like a banshee in all four gears) this was with an overdrive, 3.54 diffs and 7.50 tyres, this motor is used for everything, offroad playing, towing and redlight racing, plus i've sunk it a couple of times :eek: i am definitely a little cruel to it ...

i am experimenting with my new 109, 200tdi engine, 300tdi turbo, TD5 intercooler, series 2a gearbox (suffix unknown) overdrive and 4.3:1 diffs with 7.50 tyres, the idea of the 4.3 diffs is to up the final drive ratio but not as high as the 3.54 ones would, so hopefully increasing the economy/cruising speed some but without putting quite so much load through the gearbox in the lower gears, it's got 75mph on the speedo and with this engine/diff/overdrive i've seen the needle get way past the last marker, at a guess i cleared 90mph, i've really got to get a satnav to check my true speeds

p.s.
i'm also led to believe the 3.5 RV8 delivers it's power much smoother than the 200tdi so is kinder to the gearbox