hey all , i have a vl berlina 308 and am thinkin bout converting my 308 carb motor to an injected 5 litre (out of vn/vs)..how much power differnce i would gain and just wondering wat everyones thoughts r and how much i can get one of these motors for? how easy is the conversion ? ( considering mine is a v8 already, surely it couldnt b that hard?)

Apparently it's a reasonably easy swap. I'm considering buying a VL 5L Calais and am considering the same. Do a search, there's a few threads on here, one with a good write up on the job. Not too sure whether it's better to do a full engine swap or get VN heads and fit the injection gear to that, I'm still researching it all.

Actually easier starting with a 3L because they are factory injected and the battery is on the correct side. The power difference is massive from a factory 5L carby to injected 5L. Plus you go from 3sp auto to 4sp auto which helps

Yeah you have to move the battery, fit an external fuel pump, and a bigger fuel return line I think.

to throw another spanner in the works, have you considered a gas reseach system? or even gas injection could be an option now, i havent really researched.. a LOT less hassle than efi (no harness wiring or need for efi parts) will run as smooth and will be a hell of a lot cheaper to run

Quote: Originally Posted by NZ EVLHSV Actually easier starting with a 3L because they are factory injected and the battery is on the correct side. The power difference is massive from a factory 5L carby to injected 5L. Plus you go from 3sp auto to 4sp auto which helps It doesnt matter which side the battery tray is on you can soon cut it out move it to the other side or boot. Starting with a 3L you have to change to many things spring brakes booster k frame ect... so in my opinion its easier starting with the car you all ready got its already a V8 its already got k frame brakes ect.. just need to get a fuel tank from a efi 6 because of the fuel return to the tank and fuel lines and then bolt the basted in easy i did mine was carb V8 now injected 5.7ci just got the loom done to suit where i wanted it to go, get power steer lines from vn v8 thats it no changing springs shocks k frame ect...... dont forget need to get the tailshaft shortend to suit the T700 the yolk will fit the 4 speed box and you will have to bash the drivers floor in alittle for the auto lines and box to fit cheers m8 hope this help good luck with it

injection is nice but dont be fooled like lots of people are, not sure if any one remembers the Street Machine from a couple of months back, even Barry Grant himself says there is almost nothing between carb and injection, provided both are running 100%. The VL 304 is a good motor and has lots of potential, just needs to be opened up and have all the emission junk taken off and comp raised. That itself would get you the 140Kw mark, then you take into account bigger cam, better intake manifold, its allready got a top carb from factory, extractors, exhaust and also little bits like lifters/timing chain etc. I done this on mine which cost about 1500 and should see 200KW no problems. I know its no monster but working with what you got costs a hell of a lot less than buying a new motor plus accessories and having it put in your car, which at the end of the day would give you only 165KW

thanks for the comments guys, keep em coming, some very interesting points

Its worth doing as you dont have to touch the internals of a 5.0i to get 190kw or you can just HDT your carby donk with blueprinted rochestor,big aircleaner,match ported inlet manifold,cam,extractors etc if you dont want to spend up on a new donk.But it will use more fuel than 5.0i

just put a new cam, extractors and vn heads on your existing bottom end if its running ok.then choose a decent manifold and go with a hp holley or barry grant carb.

Dont underestimate the capabilty of the rochester, fantastic carb they are. Excellent allrounder, whereas the other types compromise on drivabillty to give the best performance for wide open throttle. thats not to say holleys or BG's are bad, they are excellent carbs but you could find a junk rochester, rebuild it, modify it for less then half the priceof other brands. As for carb motors using more fuel, once again Barry Grant states in his interview the reason EFI's use slightly less fuel in general over carb is because most EFI cars happen to come with gearboxes with overdrives, heads with more efficent flow characteristics etc etc. He conducted many tests with cars with the same specs, one EFI and one carbed, and found they were near identical with fuel consumption. Im not anti EFI but if you do some research you'll realise that you can get big things with what you allready have and save lots of time and $$$ from doing conversions. just somethings to think about

i have a rochestor on mine as i couldnt afford the carb... it made 196rwkw out of my 308. had 292 duration 498 lift hydraulic. it has great fuel economy for the power and i can still rev it 2 6600 before i change gear!! rochestors are pretty good. cant remember the flow figure is around 700 ish CFM??? someone correct me!?

yeah thats right, 750CFM for most models and 800CFM for the quaddies on chev big blocks. Chev used these carbs on nearly all there hi po models, even the 454. one great thing about the quaddie is the vac operated secondary flaps which only open as much as the motor needs them too.