I recently did a VL 4.9ltr V8 T5 manual conversion into my 1985 VK SL 6 cyl auto EST.
Engine bolted straight onto original k-member, I needed a "Dellows" bell housing (block is tri pattern & T5 was turbo), also required a new rear crossmember for the T5 transmission (bolted into original pick up points), shortened & balanced driveshaft (flywheel, clutch, T5 & driveshaft all from V8 VN) it bolted straight onto std BW 78 rear axle (Note: 6 cylinder diff only has 25 spline axles & V8's are 28 spline, I kept 3.23 ratio as with T5 gives me the best of both worlds with acceleration & cruise).
New speedo cable (had to change drive gear in transmission to get speedo 98% right), altered wiring on inhibitor switch loom (only required for manual conversions), lengthen the reverse light loom for the reverse switch now on the gearbox.
Upgraded the rear brakes to disc, all bolt on (does requires new spacers on the axles as end float different from drum to disc), they are provided in the wheel bearing kits. (I did the VT front brake conversion with VS booster also, they sure do make a difference).
V8 manual pedal set (they are different to 6 cyl ones DONT LET ANYONE TELL YOU DIFFERANT, harder to find & getting rather expensive) easy enough to fit.
HD clutch cable, insulator & cone spacer (to get clutch pedal throw, feel & height correct) all M21 optioned parts.
V8 radiator, hoses & shroud (Note: VK & VL shrouds are differant)
V8 accelerator cable
Made up a new flexible power-steer hose from the pump to the rack, return was fine.
Removed EST computer & loom, wired std 6 cylinder engine loom plug onto V8 engine loom.
Hooked up fuel & vacuum lines (including charcoal canister).
Renewed battery & fuel filter.
Built all new exhaust system with extractors.
The front springs need replacing as the V8 engine is heavier than the 6.
Just a word of advice, if possible ensure you get all the required ancillaries with the engine as buying a loom, alternator, starter, powersteer/aircon pumps etc separately can be a costly exercise. Or easier still purchase a complete donor.
I really wanted a carburetted Holden V8 engine for my project, however they are becoming a more expensive proposition than a fuel injected V8 Holden engine by the day, bang for buck the injected engine is superior in its standard form, but there is a lot you can do with cams, heads, comp ratios, stroking etc to get good reliable 300-350+hp (the VL 4.9l sourced engine has some good internals which to make hp is a little more cost effective, also runs on unleaded) and the exhaust sound from a cammed carburetted Holden V8 is priceless.
There is a very good & well detailed post by Scott aka "vkberlina" on this site, which is well worth a read on installing an injected V8 Holden engine into a VK (I found this site to be very beneficial to my build).
The LS engine option is also very popular, with a couple of different kit manufactures making fitting them rather simple these days at home in the shed. The bloke I bought my engine from did an LS conversion into his VL & is very happy with the outcome.
It's all about preference & budget at the end of the day! There is no right or wrong option when it comes to putting a V8 in a Commodore!
Good luck and enjoy the journey.
