£120 Injectors: What are you paying for?
 

£120 Injectors: You can pay that fo one injector. Or £15 a go.

i suspect the only bloke qualified to answer this properly will be 'classic' but here goes...

You can get 5 injectors all done, on a rail for about £75. Or at the the other end, you won't see even one Keihn for that. I've heard grumblings that the bottom-market stuff isn't really worth touching.

I understand Keihn are top of the heap. At 4-5 times the price of say Valtek or OMVL, is their price warranted?

It gets worse because, it's so confusing.

There's orange dot, browns, yellow. I could go on.

For desireabilty which injectors are best for Volvo engines running LPG when..

1) Money is no object?
2) When you need something to work?
3) Where is the middle ground?
4) The flow-rate?

And the same again, which come good for Volvo engines running CNG when..

A) Money is no object?
B) When you need something to work?
C) Where is the middle ground here?
D) The flow-rate?

i see with Keihn they get rated by kW

Blue Injectors - 52 cc - min power 13 KW - max power 20 KW
Orange Injectors - 63 cc - min power 18 KW - max power 27 KW

But they have a minimum too, so in the above, the Blue just about makes enough for WOT, but Orange won't go below 18kW so won't let a stock V70 @ 103 kW (140 bhp) idle?

Surely, it matters not what the flow-rates are, the ECU will adjust it anyway. Clearly not. I'm confused.

I will be biased here as I used to work tech support for OMVL

Looking at brands that have been around for a long enough time to comment on.

Rail - most of these are copies of the old Valtek injectors. Work fine but short life. Don't bother is my advice
Valtek type30 - traditional injectors are not great. Work fine but as above short life.
Valtek type 34 - much better injector, look to be reliable but are they worth the extra?
OMVL/Valtek type 32 - Decent flow reliable but I do see failures. Good value for money
Matrix - great injector but they suffer with a build up of heavy ends. Must be serviced every 6-12 months (cleaned) to ensure decent life span
Magic Jet - good flow- good price but have been suffering with reliability problems.
Hana - need to choose correct flowing injector. Nice flow mostly reliable but more failure than I would expect for the money
BRC - OK flow, very noisy fairly reliable but way over priced
Keihin- considered the very best for many years. Nice flow, fairly reliable but expensive
AEB - in most cases I would say these are the best injectors. A little expensive but not silly money. Great flow pattern very reliable and will cope with high power engines well.

My current recomendations are OMVL for cheap and works well or for high end AEB is where it is at.


But good injectors are only good with a good ECU controller

As to what flow rate to choose it is not as simple as engine BHP but more down to flow rate of the petrol injectors.

Bear in mind the shortest opening time for most LPG injectors is between 2MS and 4MS depending on type so it needs to flow little enough fuel at idle to be above minimum injection time

Thank you for the chart count-down, classic.

If it wasn't for the fact that we're only talking really about 2-3 principal engines here, my next question could get silly very quickly, and perhaps in your answer you'll indicate that it still might be, yet in your ideal world what flow-rate does each want?

Flow rate selection only applies to Keihin BRC Hana and a couple of others. Hana Gold have adjustable flow as do most other makes


For the 140BHP Volvo engine the Orange injectors are the ones of choice

Gas pressure gives you some further adjustment of fuel delivery

Thank you classic.

On the strength of that, leaving me three as spare.I've just scored myself a set of eight used Keihin Orange for a new project.

Not sure they can ever warrant £7-800 when new, but have to be worth a punt at the £170 I paid. Injector cleaner thru' em and they'll be fine,

My lpg system is old and it doesn’t need injectors.
Is this solution still available on the market?

Mixer (carb) systems are still used for older cars that do not run EFI

Yes as far as I can make out, the wisdom is that anything with a carb will run a mixer system even today. Multi-point is the way to go for cars already running electronic injection, and a lambda. I've a 1960s Land rover, recently put a mixer system on it (with a BLOS). Works dandy.

Volvo's own system as fitted to factory cars is no longer the current tech, but works well enough. It's a half-way house closed-loop system. Does the job, I have it on mine, and whislt I'm sure there's better, they won't be 'conversion-to-latest-cost' better, so it stays put.