can any one tell me how to incrse the fuel pressure on my spi sei? cos its not runnin to well since putting a 40mm tb on and thinking that adjustin this would make it better.
Technical increasing fuel pressure?
- Thread starter Garf
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Technical increasing fuel pressure?
I would look into a re-map ratehr than increasing the fuel pressure. It also might help to replace the fuel filter.
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yeah remap is probably the way forward, but I have heard of people with other cars increasing the fuel pressure slightly as this overcomes any reduction in injector performance that it will have suffered over the years, tho getting eth injector properly sonically cleaned returns it to proper flow again, in tank stuff has limited ability to clean an injector no matter what teh claims made by them are.
This should really be done tho with a fuel pressure gauge on the return from the pressure regulator found inside the SPi throttle body top, its at the front of the unit and has a blue wax seal on it, think its a 3mm allen key to adjust, IIRC clockwise for more pressure anticlockwise for less, but with a gague in place then takes away guess work.
Aaron.
This should really be done tho with a fuel pressure gauge on the return from the pressure regulator found inside the SPi throttle body top, its at the front of the unit and has a blue wax seal on it, think its a 3mm allen key to adjust, IIRC clockwise for more pressure anticlockwise for less, but with a gague in place then takes away guess work.
Aaron.
timeless
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I'm runing with mckcrich chip, 40 mm tb, exhaust system, decat pipe and homemade induction kit.
I increased (not much) fuel pressure when i fitted 40 mm tb and it work well
I increased (not much) fuel pressure when i fitted 40 mm tb and it work well
Garf said:
mm this is strange when I fiitted mine it ran like a absolute honey from the moment I turned the key!
are you still using the std ECU? when was the last time you changed the Fuel filter? are you sure that it is fuel starvation that is causing the problem?
I clean the injectors on my Cavalier every spring by soaking them in neat STP injector cleaner for a few days works an absolute treat.
OP
OP
yeah still got the standard ecu but planning to get a mckrich chip. haven't changed the fuel filter but planning on do that soon. guna be getting a manifold and performance cam. does the chip wrk well with them?
it works, but you are entering the realms of needing a custom map to suit the engine.
OP
OP
Where cud i get one of them done?and how much wud it set me back?
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kritip said:http://www.angeltuning.co.uk/ is one that I know of
Depends on the year. Oldschool can sort you out IIRC if they cant!
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Looking at angel tuning, they can engine tune any Sei that is 1108cc, so should be ok.
Does oldschool have a website at all, or can't we list it? He makes/sells the GSR induction kit doesn't he??
Kristian
Does oldschool have a website at all, or can't we list it? He makes/sells the GSR induction kit doesn't he??
Kristian
website is in the process of being completed
J333EVO said:
Well i thought the Cinq was going well but the idea of a wax seal stopping me from doing something got me a bit miffed. so.. ... I scraped out the wax seal and gave the screw a half turn and my god the old girl exploded into life what a difference, obvously a bit of fuel starvation. I need a rr set up but the MOT is 9 months away so no rush?
I love this forum the more I read the more power I get
timeless
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I like your slogganallanhelen said:I love this forum the more I read the more power I get
gave mine half a turn.. and nuffink!
If you take apart the pressure regulator (front on throttle body 4 torx screws, spray WD4 underneath them first as can be seized if you want to look for yourself) like I have done its a spring on top of a rubber diaphragm, set at factory to open and let excess pressure be released and returned to the tank, once set its sealed by wax, the reason you have a regulator on a fuel injection system is that fuel pumps are voltage dependent so you can therefore gets spikes and drops due to voltage. The Allen bolt I would say would take a few turns to make a huge difference, I turned mine fully to get a rise from a measured on fuel pressure gauge standard 1.4bar to 1.5bar as I run a hi pressure, hi capacity fuel pump running 3 bar to my 2nd injector and 1.4bar to primary injector.
Although not needed by anyone other than turbo owners with 2nd injectors I will also be running a SARD rising rate fuel pressure regulator as I run my fuel line to 2nd injector first then regulate to 3bar, then run to primary injector regulated to 1.4bar as they have to be in series not parallel otherwise its will regulate to 1.4 bar all system as liquid under pressure will always take easiest route to return to tank.
Although not needed by anyone other than turbo owners with 2nd injectors I will also be running a SARD rising rate fuel pressure regulator as I run my fuel line to 2nd injector first then regulate to 3bar, then run to primary injector regulated to 1.4bar as they have to be in series not parallel otherwise its will regulate to 1.4 bar all system as liquid under pressure will always take easiest route to return to tank.
so im fine to keep on adjusting it? will take it all out and check it's not siezed up firs though. suppose i could fit my 3bar pump.. then the adjustments would do something eh!
arc said:
Yeah having the bigger pump on now in prep for MPi conversion & will not harm the car in any way as its will always regulate to what ever you set all excess being returned to tank, and running abit more pressure will give a better spray from the injector especially if its got inevitable dirt build up that in tank cleaners can't remove.
After taking apart two Cinq fuel pumps and replacing with two upgraded ones today, it got me thinking; is the Cinq pump is already a hi pressure but low capacity as both OE pumps I removed were made by Walbro and both pumps I fitted were made by Walbro, is it just the regulator in the throttle body that sets the pressure
Got to admit tho even tho I haven't got my car set up yet the difference with the new pump was fantastic, much cleaner pick up, felt sharper.
i can't see that being the case.. i mean why run a pump capabale of 3bar when it's never going to need anything more than 1 bar
might fit the 3bar pump this week then, itching to do something to the car (beside thrash the arse off the poor thing!). Are the fuel line clips on the tank reusable, or should i get some new ones before i start pulling it to bits?
might fit the 3bar pump this week then, itching to do something to the car (beside thrash the arse off the poor thing!). Are the fuel line clips on the tank reusable, or should i get some new ones before i start pulling it to bits?
