Converting back from carbs to 14CU
Discussion
Hi everyone,
I'm Dimitri, I live in Belgium.
I'm looking into buying a 350i s2 wedge which has had the injection system thrown out (no parts have been kept) and has now twin su carbs installed. Seems to run quite well like this. So didn't really matter to me. But apparently the MOT stations in Belgium don't think like that.
For a car to be registered as a classic vehicle, it must be presented in original condition. As this is quite vague as a definition, I called and explained the situation, but they told me I wouldn't be able to put the car on the road because of the carbs (not original)...
So... Great... It was the car that I wanted, right colour, right interior, in pretty good condition... price within budget (just). I could take my chances and try to get it MOT'd and hope they don't notice it, but I believe I'll probably won't get away with it...
So, maybe it's easier for me to convert it back to EFI. I'm just wondering what parts that I need to do this:
- Inlet manifold (there is one on ebay from a range rover vogue 3.5 EFI)
- plenum (coming from that same vogue)
- 4CU ECU => where will I be able to find this?
- cabling => where will I find all this?
- injectors => there is a chapter of this in the bible, so will look into this...
- Flapper (AFM?)
- anything else?
Is this even do-able or should I just forget about it? Any other possibilities? Anyone else having a wedge for sale (<=5k pounds)? Do like blue ones...
Thanks a lot in advance guys!
I'm Dimitri, I live in Belgium.
I'm looking into buying a 350i s2 wedge which has had the injection system thrown out (no parts have been kept) and has now twin su carbs installed. Seems to run quite well like this. So didn't really matter to me. But apparently the MOT stations in Belgium don't think like that.
For a car to be registered as a classic vehicle, it must be presented in original condition. As this is quite vague as a definition, I called and explained the situation, but they told me I wouldn't be able to put the car on the road because of the carbs (not original)...
So... Great... It was the car that I wanted, right colour, right interior, in pretty good condition... price within budget (just). I could take my chances and try to get it MOT'd and hope they don't notice it, but I believe I'll probably won't get away with it...
So, maybe it's easier for me to convert it back to EFI. I'm just wondering what parts that I need to do this:
- Inlet manifold (there is one on ebay from a range rover vogue 3.5 EFI)
- plenum (coming from that same vogue)
- 4CU ECU => where will I be able to find this?
- cabling => where will I find all this?
- injectors => there is a chapter of this in the bible, so will look into this...
- Flapper (AFM?)
- anything else?
Is this even do-able or should I just forget about it? Any other possibilities? Anyone else having a wedge for sale (<=5k pounds)? Do like blue ones...
Thanks a lot in advance guys!
Edited by dimitrivdw on Wednesday 4th November 18:37
Hi Dimitri,
Personally, I don't understand why people revert from a (relatively) sophisticated fuel injection set-up to carbs, unless there is some sort of problem that they can't fix. If you really wanted the car, I would get something like Emerald put on it. I doubt the tester would know it was not original equipment, although having said that, it would be obvious to anyone familiar with the Lucas EFI stuff that the airflow meter was missing with an aftermarket system like Emerald. Still a relatively expensive conversion, although there's no guarantee that if you were to buy second-hand bits (ecu, loom, airflow meter, injectors etc. that they all worked properly.
My suggestion would be look for an alternative car - there must be more 350s out there that meet your requirements? Failing that, bid on the car sufficiently low to allow a conversion.
Personally, I don't understand why people revert from a (relatively) sophisticated fuel injection set-up to carbs, unless there is some sort of problem that they can't fix. If you really wanted the car, I would get something like Emerald put on it. I doubt the tester would know it was not original equipment, although having said that, it would be obvious to anyone familiar with the Lucas EFI stuff that the airflow meter was missing with an aftermarket system like Emerald. Still a relatively expensive conversion, although there's no guarantee that if you were to buy second-hand bits (ecu, loom, airflow meter, injectors etc. that they all worked properly.
My suggestion would be look for an alternative car - there must be more 350s out there that meet your requirements? Failing that, bid on the car sufficiently low to allow a conversion.
Edited by Number 7 on Wednesday 4th November 19:00
I'd be inclined to use the efi upper and lower manifold from either the 3.5 or 3.9 with the corresponding injectors, and use aftermarket engine management.
How much like original must it be? As you could always use an air flow meter off something newer/bigger that looks about right as well. Would mean making a new engine harness up but thats not a bad idea with the age of original efi harnesses now
How much like original must it be? As you could always use an air flow meter off something newer/bigger that looks about right as well. Would mean making a new engine harness up but thats not a bad idea with the age of original efi harnesses now
welcome to the madhouse...
I'm running megasquirt and it's way better than the Lucas flapper; however to get the full advantage you have to ditch the distributer and run coil packs, so your test inspector may not like that either!
On a more serious note if you want to return to a flapper I'd buy a running Range Rover/Discovery for peanuts and swap everything over. I struggled with my flapper system for ages and eventually gave up - if you buy bits piece by piece and then try and make them work together i suspect you'll travel a long and painful road. TVR even used the Land Rover engine wiring loom so a donor vehicle would have everything you need.
PS the pops and bangs are over-rated compared to the thump in the back when you floor a V8 with megasquirt!
I'm running megasquirt and it's way better than the Lucas flapper; however to get the full advantage you have to ditch the distributer and run coil packs, so your test inspector may not like that either!
On a more serious note if you want to return to a flapper I'd buy a running Range Rover/Discovery for peanuts and swap everything over. I struggled with my flapper system for ages and eventually gave up - if you buy bits piece by piece and then try and make them work together i suspect you'll travel a long and painful road. TVR even used the Land Rover engine wiring loom so a donor vehicle would have everything you need.
PS the pops and bangs are over-rated compared to the thump in the back when you floor a V8 with megasquirt!
Edited by The Hatter on Wednesday 4th November 19:57
maybe easier to find a Landrover 3.5i or 3.9i that's a MOT failure due to bodywork or other non engine problem. you can then swap the complete EFI and loom over. put the Carbs on the LR engine and sell that as a running engine. and scrap the rest.
Would most likely work out cheaper, plus your can make sure it's all working before you swap.
Would most likely work out cheaper, plus your can make sure it's all working before you swap.
The Hatter said:
PS the pops and bangs are over-rated compared to the thump in the back when you floor a V8 with megasquirt!
@: Martin...Id have two settings on a switch...The first one the thump in the back and then when the butt-hangers are on my bumper i can switch to massive over-fuel and de-accelerate...POP..Bang ...Flame....They soon back off....
@: OP
Some good advice here..Converting back will be costly and you will struggle finding the right parts so...A decent discovery 1 engine with a slightly profiled cam would be nice..
I run a carb setup with no complaints. The key thing is to ensure you have the correct jets to ensure max efficiency. However, there are some aftermarket Carb to Efi systems such as this one: http://www.ezefi.com/ez-efi/. Edelbrock have a system too.
I would like to buy a bigger V8 and if I do I would run it with a Carb setup for the bigger engine which is what they were designed for by those clever Yanks. IMO I would opt for a modern Efi replacement than go back to the original Lucas system which is easily surpassed by what's available today.
I would like to buy a bigger V8 and if I do I would run it with a Carb setup for the bigger engine which is what they were designed for by those clever Yanks. IMO I would opt for a modern Efi replacement than go back to the original Lucas system which is easily surpassed by what's available today.
TVRleigh_BBWR said:
As mark said, if you did get a complete replacement 3.9 LR, you could put a fast camshaft in, and swap the complete engine and ECU and have 220-240 BHP.
Like that idea too But for now just getting it through the test would be more than good enough. Engine swapping could be done later on 
Thanks for helping out guys. I really appreciate it!
Maybe you could get a dead AFM and then make a fibreglass plenum shaped cover to go over the carb..It could even have vents instead of fins concealed under wire mesh..Sprayed silver to look metal with some black misting for age...The plenum hose to AFM would just be an extension of the air intake....
I have a spare resistor pack and a fuel rail with some loom for effects.....
I have a spare resistor pack and a fuel rail with some loom for effects.....
There are more knowledgable folks on here that can talk about differences between the 350i and Range Rover EFi systems; but I think I'm right in saying that TVR used the SD1 Vitesse system with no modifications and the Land Rovers variants were only slightly different to the SD1. The SD1 had a different cam to the Land Rovers but I'm confident in saying that the Land Rover system would work very well on your engine if you consider the passage of time, variations in spare parts and the general vagueness of an aged 14CU system. It should get you past the Belgian certification tests and give you a car that runs pretty well.
The LR 3.5 uses all the same parts as a SD1 3.5i, only difference if camshaft and ECU tweaks, as its setup for about 160BPH compared to SD1 190 BHP, but with a but more torque due to camshaft.
The ECU does not have any rev map of sorts any works of set values, so should auto adjust to some degree.
You may need to get an adjustable fuel pressure regulator, to get the fueling right due to differences. its normally the simplest way to trick the system into giving the right fuel, or you can get the AFM re-calibrated.
The ECU does not have any rev map of sorts any works of set values, so should auto adjust to some degree.
You may need to get an adjustable fuel pressure regulator, to get the fueling right due to differences. its normally the simplest way to trick the system into giving the right fuel, or you can get the AFM re-calibrated.
Well, I've decided to go and see the car on saturday. I've heard from a lot of people that, since they don't have official documents about the car, they won't be able to disapprove the carbs, since that is nowhere mentioned on a V5 or MOT document. Lots of other cars seem to pass the tests, even though a lot has been changed. So if I decide to buy the car, I'll first have a go with the carbs. If that fails, start looking for an efi system...
The tester should have to be an obvious tvr lover to be able to tell that those cars only came with injection, I guess.
Just love the colour on the photos, love the interior. Would be a shame not to go and stand in front of it...
The tester should have to be an obvious tvr lover to be able to tell that those cars only came with injection, I guess.
Just love the colour on the photos, love the interior. Would be a shame not to go and stand in front of it...
dimitrivdw said:
Well, I've decided to go and see the car on saturday. I've heard from a lot of people that, since they don't have official documents about the car, they won't be able to disapprove the carbs, since that is nowhere mentioned on a V5 or MOT document. Lots of other cars seem to pass the tests, even though a lot has been changed. So if I decide to buy the car, I'll first have a go with the carbs. If that fails, start looking for an efi system...
The tester should have to be an obvious tvr lover to be able to tell that those cars only came with injection, I guess.
Just love the colour on the photos, love the interior. Would be a shame not to go and stand in front of it...
Unless the tester realises what the i in 350i stands for?The tester should have to be an obvious tvr lover to be able to tell that those cars only came with injection, I guess.
Just love the colour on the photos, love the interior. Would be a shame not to go and stand in front of it...
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