Correct fitting of 850cc Primaries??

leeroy_25 · November 03, 2010, 09:32:55 PM

Should you use two lower sealing o-rings on each of the injector tips in the modified primary fuel rail? I think I read somewhere this is a good idea to prevent leakage past the seal? I know mine has not got this and I am wondering if I should hook them out and put another seal on the end or whether I would have serious running problems if I had a leak past? To be fair I have got a bit of a strange fueling problem going on!

Cheers
Lee

shaunwil · November 03, 2010, 10:10:44 PM

Are you using the original injector holder or an aftermarket one ?

With the aftermarket setup there is a turned part to take up the difference in the kgparts kit. I made my own on the lathe at work and just the oring between the injector and the adapter with some sealant between the adapter and injector hole. I had the original defused with the square seal as well under the adapter / injector.

Shaun

Used for quite a while.

leeroy_25 · November 04, 2010, 01:44:38 PM

Hi Shaun,
Not sure I followed most of that!? Maybe because I am using a stock primary fuel rail which I modified to fit a set of stock 850cc injectors into it? skim the top and ream the bore out a bit if I remember correctly. No additional seals or sealant in the make up of it and just checking to find out if I sure be putting another seal in at the tip of the injector?

Cheers
Lee

shaunwil · November 04, 2010, 06:08:17 PM

Sorry, I-pod typing ! I think I have seen people using a double seal on the modified primary fuel rail.

Just looked at my photo of the bits and the adapter was on the secondaries, It was a while ago !

Shaun

leeroy_25 · November 04, 2010, 06:27:49 PM

Thanks for looking.. Nice bit of kit there!
Lee

SmbFD3S · November 04, 2010, 06:58:52 PM

Not using 2 on my rail and seems fine, have no leaks and been like that for the past 4 months, 14 passes at Pod and a long long day at Pip\'s getting it mapped (secondary issues)....

Suppose it depends how much you took off the top of the original rail?? I didn\'t measure it, i just kept going until i was sure the o ring was sealing correctly. Although i did have a set of dead primaries and pressure tested it and it started leaking at 170Psi, so pretty sure it\'s never going to leak on my setup (40Psi base pressure)

HTH

leeroy_25 · November 04, 2010, 07:46:19 PM

Fair enough. I had mine up to 100psi by accident the other day ad it didn\'t leak out of the top or the rail. I was more concerned it could push past the bottom seal and make it run rich which would be harder to tell! Are you running 4x850 setup? How do you find it if so?

Cheers
Lee

turbotoaster · November 04, 2010, 11:25:36 PM

just take 3.1mm of the top of the rail, push the 850cc injectors in, then bolt up and your good to go, had no issues with mine like that

SmbFD3S · November 05, 2010, 12:02:14 AM

Quote from: leeroy_25;725037Fair enough. I had mine up to 100psi by accident the other day ad it didn\'t leak out of the top or the rail. I was more concerned it could push past the bottom seal and make it run rich which would be harder to tell! Are you running 4x850 setup? How do you find it if so?

Cheers
Lee

I tested mine from the top and bottom mate and the seals started to give at 170psi no matter which way round so fairly sure you wont have an issue there.....

Yeah am running 4 x 850\'s matey on 40Psi base pressure. To be honest i\'m tempted to go back to the 550\'s and put 1600\'s in the secondaries cos it\'s just costing too much in fuel and the idle is a bit crappy no matter what me or Pip tried to do to it, they are already at -0.22 lag, any further and the car dont like it, but it runs 12.1 AFR on idle at that which is the leanest we\'ve been able to get it without the engine bucking up.... I am still on standard ports though and this may have something to do with it...

leeroy_25 · November 05, 2010, 02:31:45 PM

Sounds like you got the exact setup and running issues I have! same -0.2 lag as well! Will have to check what the best AFR I got for idle was.. It does idle quite nice actually but low speed driving it is a bit rough. If I was to do it again I would go 1600cc and 550cc for sure.

Point of this post was to be sure I was not getting anymore excess fuel down the port as well!!

Cheers
Lee

SmbFD3S · November 05, 2010, 02:41:55 PM

Well mine does idle quite well but as you say low speed is a bit jerky sometimes due to the lag timing of the injectors.....

Anyway, i think the AFR\'s would show a lot richer if you were getting excess fuel through the ports, what exactly is your "strange fuelling problem"?

To be honest mine hasn\'t got any issues and she\'s fine running at 1 bar all day long at 85% max duty.... It\'s just expensive when on light load and cruising due to the 850\'s... 180 miles on 60 quid on a standard port engine aint exactly good and that aint booting it lol.....

leeroy_25 · November 05, 2010, 08:42:13 PM

Hi Mate, I think I have an FPR related problem to be honest. I have another thread about it. My fuel pressure drops very low at vaccum and then drops back quickly on 3/4 load.. have tested the pump. Found other reports of people using FSE regulators with exact same symptons, so hopefully that. I was thinking the fuel coud be leaking past the injector seal into the engine causing pressure drop but then as you point out the AFR would be high. I have never clocked mileage on mine. I dare not! other than that I only have exactly what you describe so it\'s nie to know it is just the injector setup and nothing else!!
One other thing I have which I do not know if you come accross. My knock light flashes when I am doing 2000-300rpm cruising? My tuner put it down to interefence with something, I did notice that when I turned the Fuel pressure down a bit the car is much smoother and the light doesn\'t flash but then you cannot get the fuel top end!? Clearly it cannot be knock under no load?!

Cheers
Lee