injection to carbs - help please

Hi chaps and chapesses
We have a mongrel 90 that was a diesel pick up and is now a v8 station wagon. Its got a single plenium fuel injection system and is starting to play up so was looking at fitted carbs (twin su's). Couple of questions really,

1. will it work and is there anything other than lowering the fuel pressure we need to watch out for (carbs from Rover SD1)

2. If we wanted to scrap the ECU and fit a dizzy with an internal aftermarket ignitor kit is there a specific dizzy we need to use.

We were told the engine come out of a Disco 1 but this is not backed up by any documentation.

3. is there a web site we can put an engine number into to see

Cheers
James

I like carbs. But I think it would be a huge backwards step to go from EFI to twin SU's.

Weber/Edlebrock 500 maybe or stick with the EFI and get it sorted, even if you switch to something like Megasquirt.

I also think that sticking with EFI is the better option, But its down to personal preference. Try this website for the origins of your engine:

Rover V8 Engine Numbers

Hope that helps, Dave.

I would also stick with efi if i could although currently running SU. Edlebrock and Webber both do inlet manifolds to suit the 3.5. I would rather have a webber or holley carb over the SU. Apparently the Webber produces better low down torque than the Holley which should mean it is better matched to the Land Rover. I am not sure what dizzy the injected disco has but lumenition do an electronic ignition kit for the Lucas 35d8 dizzy.

the dizzy is seperat to injection system so you can leave you old one in if it still works ok.

a lot of peeps fit them to replace earlier points dizzys

I have a 3.9 Disco engine with the carbs from an original 3.5 - I love it!

It always works, including being just fine with LPG.

To be fair to the other forum users, I'm sure that the power is down from the injection - but is really is great.

If you live anywhere near Weston Super Mare you are welcome to come and have a drive.

I've just taken the Efi off the 3.9 and replaced it with twin SUs from an SD1. Goes really well apart from the top end. I assume I need to replace the needles for something richer but does anyone know which needles I need?

give burlen fuel services a ring

Got twin SU's plus manifold if interested

fett said:

give burlen fuel services a ring

Click to expand...

I rang Burlen - very 'helpful' bloke said he could only advise on standard set ups, not a 3.9 with carbs. He did point me to a section of the website which enables you to compare up to five needles against each other Minty SU Needle Compare-o-rama which helped a little and I downloaded a nice little program which also helped in selecting some different needles SU Carburettor Links and Info Main Page
So far I've looked a couple of needles that might do the job including BAP and BCE but I think I'm stabbing in the dark. Hopefully someone who understands these things better than me can advise us some more

as far as I can tell not too many mechanics understand su's anymore. I had mine rebuilt by a specialist who fooked up so that one of the floats stuck after about 200 miles.

the guy that fitted them used the wrong choke cable and had no analyiser to set them. then the garage that tuned them with an analyiser , who did a fair job but didnt get them quite right so that when the car was really hot I had to run with the choke out.#

I gave up on them in the end, picked up a couple of clourtune kits very cheap at a car boot and got a ballencer from ebay. put the old correct choke cable back on as all it needed was a little metal collar.

set them up my self after refitting the carb with the sticky float and she runs a treat now- spot on!

Matt

do you by any chance have a photo of you engine bay you could post as I am going from Efi to SU carbs and am a bit stuck!

Thanks

Tony

if you want to see a normal carb set up look in my albums at the engine bay on my 72 rrc

cheers fett the fog is slowly clearing ...

dont worry , it gets easier after a little tinkering, then you realise just how simple they are and how mechanics who cant tune them must be brain dead!

all you need tot set up is a £35 carb balencer from ebay and on a v8 a paire of gunson colourtunes makes life nice and easy but one would do. they are only about £14 on ebay - normally ones the seller has never used either lol