20 replies to this topic

[Scott MPI]

Ok so now you've changed something that improves the problem, since nothing else has id continue it that direction,

Cam timing

Im now thinking if you run an advanced cam in an injection engine you will create an retarded timing condition,

which in turn creates a false lean condition

Edited by Scott MPI, 07 June 2017 - 04:45 PM.

[mina08]

Have you tried fitting a new injector or having the old one properly cleaned and flow tested?

 

Most old injectors loose about 5-10% flow rate (sometimes more) as they age and get filled with crud.

People spend ages chasing fuelling issues, but never once think to look at the 20 year old injectors the car runs.

I have and have checked mine too, flow and spray seem to be right, although i find it hard to locate these injectors online.

[mina08]

Ok so now you've changed something that improves the problem, since nothing else has id continue it that direction,

Cam timing

Im now thinking if you run an advanced cam in an injection engine you will create an retarded timing condition,

which in turn creates a false lean condition

Yes i think so too, its only run 1000kms since rebuilding it too

[Scott MPI]

I also had injectors tested,

When I get time I'm going too play with the cam position for best running/power and not get hung up on what the actual timing is/should be

Then I'll check what the timing is

Just like you would do with a distributor, you have to alter its settings to suit the engine mods

[mina08]

so after many different test it is slightly better but still has a hesitation around 2000, so it must be lack of fuel at some point, i am also going to get the injector cleaned for good measure.

[mina08]

so after checking everything its still got a slight hesitation at 2000, took a long drive the other day at a steady 120kph and the temp gauge needle was ¾ running hot? it came down when i slowed down?

 

plugs still show running lean

can anyone recommend an injector cleaner company

also do they still sell injectors for these manifolds

should i look at upgrading the fuel pump