The V8 Owners Forum -

Have just got the landy running sweet as - ignition sorted now revving well. Current set up is 5.0 RV8 in land rover 90, with megajolt wasted spark ignition with standard map (not rolling road yet) eddy 600 jetted using my welded in wideband sensor (still not happy 100% yet) and performer manifold. As always when things are going well I cant help but think of ways to improve/stuff it up:-) Does anybody think converting to EFI via a 4 barrel throttle body etc would be a good move - keeping original manifold etc and crossfire plate (nos not yet in)?? Anybody have any experience with these - seen loads online and on ebay from states. What do you think?? Im looking for mid range grunt - not low down or very high up 2500-5500 is my aim. Any thoughts ?? or should I just stick to my setup and get it Rolling roaded (emerald i think have a 4x4 roller

Hi
If you go efi then it will not have the issue of the 4 barrel flooding when at silly angles of lean, though you may be comp safari and this might not be suck an issue. With nitrous you will not need a seperate fuel supply, just big enough injectors and a second fuel map.
I can sell you a throttle body if you like?
Best regards
Mike

Would it help with performance?? Any experience with them?? How much??

It may help performance a little, but you'd have to weigh that up with the costs to change.

it would require a lot of work, and proper fuel tank etc especially if it's for off road use.

Is it really worth it ?

I know what you mean steve - I dont really think it is worth the money (I would use a swirl pot and keep the current tank) - the reason I ask is I know a set of individual throttle bodies would significantly improve things, but cost these would be in the thousands - a 4 barrel throttle EFI setup would be cheaper and retain a lot of what I have but I wondered if they really made that much difference - EaZy EFI, holley and now edelbrock do a conversion kit (I would do my own using megajolt or emerald ecu) - because the mode of induction is essentially the same I suppose (or is it) - the gas/vapor dynamics are essentially as previous (correct me if I am wrong) but fuel delivery changed - does it help the mid range where I want power?? And i wondered if anybody had tried it?

Carbs can still make good power and driveability and they are very versatile.

EFI can make more power and over a wider range, but it's biggest things are emissions and low rpm driveability, low rpm torque etc
Once over 2000rpm I'd say there really isnt a huge difference

If this isnt a road car and doesnt see a lot of road miles and road driving, then I would find it hard to justify costs to change.
Even more so within the rpm range you specify. A well set up carb will work very well there

Have a look on some of the US V8 forums as these devices are pretty thick on the ground over there.

I looked at the Edlebrock TBs but decided to stick with their 4 barrell carb instead which, once sorted, I have found is fit and forget and it delivers the power when needed. Maybe not as smooth, especially when cold, but IMO it's not worth the cost and hassell changing over on a road car that only comes out on nice days.

Interestingly, those big banger V8 NASCAR engines which make over 900 bhp all use 4 barrell carbs.

Robrover wrote: Interestingly, those big banger V8 NASCAR engines which make over 900 bhp all use 4 barrell carbs.

Only because they arent allowed to use fuel injection.

And for a Nascar it probabky wouldnt make a huge difference. They'd almost be like a boat engine, where they operate over a very small rpm range, as they are basically flat out the entire lap, and the entire race. So it's very easy to optimise the carb for those conditions.

It's a far cry from a road car or circuit racer where there would be large variations in rpm and throttle openings

I realise it's a lot of money- if money were no object I would go for it, went off roaring today, and on a slow climb of a steep hill I stalled and couldn't start 1 think the smoothness would be good for off road- but I think a spring for my floats may be cheaper!! Need to source one. I think I need performance in a wider range of revs then I initially thought!

Hi
If you are doing off road stuff you want either SUs or fuel injection, 4 barrels only really work as designed when stationary and horizontal because of the float bowl design (as you have proved over the week end). MAP sensor based 4 barrel EFI with a will give you good part throttle response and when set up right very good transition response, far superior to a 4 barrel carb, it would probably give very little more outright power over the 4 barrel carb.
Best regards
Mike

Where and for how much could i source a 4 barrel TB in the UK?? Are you sure the float bowl off road springs arent worth a try??

kiwicar wrote:Hi
If you are doing off road stuff you want either SUs or fuel injection, 4 barrels only really work as designed when stationary and horizontal because of the float bowl design (as you have proved over the week end). MAP sensor based 4 barrel EFI with a will give you good part throttle response and when set up right very good transition response, far superior to a 4 barrel carb, it would probably give very little more outright power over the 4 barrel carb.
Best regards
Mike

Any advantage over the standard RV8 injection set-up?

Hi
Not really, apart from you can get new 4 barrel dual plane inlet manifolds and new 4 barrel throttle bodies, and I think from his post he already has a manifold. All he has to get is the throttle body and ECU. Any standard rover manifold is going to be a bit old by now and will need a full overhaul.
Best regards
Mike

Right - not very much that wears on them, I'd have thought. And cheap used.