Outer Limits 4x4 Board

I plan to replace my 3.5L injected motor on a 89 Rangie with a 3.9L with carbs. I think the AFM is playing up in the 3.5L.

So what do you guys think. Am I making the right decision? What are the advantages and disadvantages? It will be coupled with a ZF auto.

Shane

Why replace the efi ? Just fix the offending item and keep it. If it was an earlier flapper efi then i would say either replace the ecu or fit a 4brl quaddy.
Carbs are good for simplicity and power but efi is better for efficiency and smoothness ( when working correctly).

Thanks for the Response. I was feeling unloved.
I think the 3.9 is from a later model with carbs chucked on it.
My mechanic reckons my AFM prob is so common it isn't worth going 2nd hand. He reckons it would cost me $1800 for a new AFM. I would like to keep it injected for those reasons and you don't have tuning probs usually.
Thanks again
Shane

EFI is a lot better on angles offroed aswell compared to a carby.

For less than half that you can buy an aftermarket ecu and never have afm probs again, plus programmable to boot.

OK
Will the replaced ECU fix my AFM woes.
EDIT
Where do I get this aftermarket ECU?
How much is it?
Who can fit it for me?
Do Haultech boys do this?
Advantages and disavantages?

Keep it coming
Thanks
Shane

What are your afm woes ? A new programmable ecu will allow you to get rid of the afm , they use a vacumn sensor instead, it will then be fully programmable and most likely be able to control the ignition as well. Link below but there alot others as well including the diy megasquirt kit.

http://www.speed-technology.com/

You can "recondition" the Lucarse AFM's by popping the top and gently bending the wipers in a bit on the carbon tracks (you'll see what I mean when you're in there). Over the years the wiper wears a groove in the carbon, eventually it goes right through. If you bend the arm so it's wiping a fresh bit of track it'll work again.

My choice would be to junk the Lucas ECU and stick a MegaSquirt ECU on, but then I'm biased

EFi (when it's working properly, which is a big "IF" with Lucas) is better than carbs pretty much full stop. And it can be made to run underwater quite happily, too.

Thanks Fridgefreezer I will give it a go with the AFM.

I have been told that my AFM will most probably be made for other vehicles as well and a new one will be much cheaper.

Will consider megasquirt ECU depending on price

Thanks guys
Shane

The AFMs were indeed made for lots of other vehicles, but they are a bit different. Jaguar ones may work (the AFMs and ECUS are interoperable) but it's not as simple as all that.

Many people swap in Lucas/Bosch ECU's and AFMs and the vehicle will run, start, drive, etc. OK, being a MAF system they're pretty much going to whatever happens. BUT a Jag / BMW fuel map will be different to a Rover V8 one. So although it will cure the problem, you have a new and compltely unknown fuel map. Likwise the AFM - the carbon tracks aren't stright, they have strange shape to them, this is a sort of "hardware" fuel map, and again vehicles will differ.

The MegaSquirt ECU costs ukp 120 in kit form, ukp 170 built. I can supply a wiring "tail" that is as close as you can get to plug-n-play for the Rover V8 for ukp 50, and a plenum MAP sensor adapter and hose for ukp 25. There's all sorts of info, diagrams, etc. on my website and there are numerous RV8 fuel maps floating round the interweb.