Fuel Injectors

CastleMGBV8 · Post by **CastleMGBV8** » Tue Mar 17, 2009 1:44 pm

I have a gems type manifold off a 4.0 Rover V8 and am wondering what the fuelling limit is of the standard injectors in respect of how much power they will support.

I am anticipating in the region of 270 BHP are they going to flow enough fuel?

Kevin.

Wotland · Post by **Wotland** » Tue Mar 17, 2009 3:29 pm

Kevin,

I use this calculator : http://www.z31.com/software/injector.pl

Green Lucas and Bleu Bosch injectors flow around 180CC. Not enough for 275BHP.

r2d2hp · Post by **r2d2hp** » Tue Mar 17, 2009 5:00 pm

I am using new low impedance 214cc injectors at 2.5 bar and am seeing 314bhp.

Am about to upgrade as duty cycle must be quite high.

CastleMGBV8 · Post by **CastleMGBV8** » Tue Mar 17, 2009 7:16 pm

Dimitri,

Thats a useful programme but am getting conflicting answers.

If i enter BSFC of 0.50 and duty cycle od 0.85 and injector flow rate of 180 it says they will only support 233 BHP

If I input the same figures but Power at 275 BHP it says the injectors are large enough unless I'm doing something wrong?

I have the green Lucas injectors.

Kevin.

Wotland · Post by **Wotland** » Tue Mar 17, 2009 8:19 pm

Kevin,

I entered same figures as you and I had this :

Power: 275 horespower
Number of injectors: 8
BSFC: 0.50
Duty cycle: 0.85
This combination will require 212 cc/min injector (20.2 lbs/hour)

For the choice of injectors I use this data base : http://users.erols.com/srweiss/tableifc.htm

This site gives also some indications about the BSFC figure to use.

CastleMGBV8 · Post by **CastleMGBV8** » Wed Mar 18, 2009 12:38 am

Dimitri,

My mistake forgot to change the number of injectors.

So what would you recommend as it's not going to be cheap to change 8 injectors.

Kevin.

Wotland · Post by **Wotland** » Wed Mar 18, 2009 7:21 am

Kevin,

I found more informations about genuine injectors : Standard spec is 185cc/min at 36PSI for 14CUX Lucas injectors. Bosch Thor injectors flow the same, but at 56PSI.

One option is to use Bosch 0280-150-561 rated at 230cc/min at 40 PSI.

Dimitri

CastleMGBV8 · Post by **CastleMGBV8** » Thu Mar 19, 2009 5:13 pm

Dimitri,

The green Lucas injectors I have are D1830GA buy I cannot find a spec for them are these the 14cux injectors you mentioned earlier rated at 185cc/min at 36PSI.

Bear in mind I'm a complete learner of EFI but if the standard injectors were run at a slightly higher pressure say 40lb ish would this help and increase flow rate pro rata by 10% as I would like to not have to buy a new set if possible?

I intend using a MS 1 V3 ECU does that allow adjustment of the duty cycle and could I realistically increase fuel pressure higher to say 43.5 PSI. I haven't bought a fuel pump yet as I want to be sure everything is compatable.

Kevin.

r2d2hp · Post by **r2d2hp** » Thu Mar 19, 2009 5:52 pm

Hi Kevin

I believe D1830GA are Lucas and flow is 185cc/min at 36PSI. Was told they do not like increased pressure, not sure how true that is.

If your interested in a brand new set of low impedance 214cc bosch injectors which is what I use let me know as I have a spare set. You do need to run them with ballast resistors that cost a couple of pounds from Maplin or RS

regards
Reg

Post by **Coops** » Thu Mar 19, 2009 5:57 pm

i was running my old hotwire ones at 40-45psi with no probs,
but now using bigger injectors turned down,.

CastleMGBV8 · Post by **CastleMGBV8** » Thu Mar 19, 2009 6:03 pm

Tony,

I remember you got some new ones from the US, whats the spec, price and supplier please?

Kevin.

Post by **Coops** » Thu Mar 19, 2009 6:28 pm

bosch greenmotorsport ones,
440cc/min
fiveO on ebay US

doubt if they will be any good on current exchange rate mate.

Post by **Coops** » Thu Mar 19, 2009 6:39 pm

http://stores.ebay.com/fiveomotorsport

Post by **Coops** » Thu Mar 19, 2009 6:46 pm

http://cgi.ebay.com/ebaymotors/Bosch-02 ... 0179003267

r2d2hp · Post by **r2d2hp** » Thu Mar 19, 2009 6:56 pm

42Ib injectors are good for best part of 600bhp

Think Kevin needs to be looking for injectors of around 20Ib

Read that over large injectors can cause all sort of running issues