looking at the second drawing all cylinders will fire together so nominly every tdc and bdc which means it will attempt to fire the cylinder @ bdc of the induction stroke.which will cause a big bang through the inlet
an ingition amplifier desgined to run 1 coil could not run four for very long.
injector timing on petrol engine overall is altered buy changing the opening (MSPB) Micro second per bit, or injector offset as it is sometimes referded too it, will vary from engine to engine and injector types and makes.
Base fuel pulse width = raw (map) value x microsec/bit(mspb)
Fuel sync...
if you have a good ecu with idle strategies which have
target idle speed and also has high idle capture,tempreture offset and idle spark scatter.Also for the bypass valve
coolant duty table,rpm duty table and idle feedback loop.
The idle fuel table on tps load based engines do not measure the...
hi fi you use tps only forget maf it is too slugish in response use a good ecu with good idle speed control you can set your idle speed to suit your engine, for super smooth O E M style control use idle bypass valve.
Big vlad the base circle can be a problem we have seen as much as 12th rise on base circle caused by bad grinding, the effect is to close the tappet setting and leave the valve of the seat causing what looks like stand off. Opening the tappet clearance is a quick way of checking
if this is the...
Does this problem manifest itself when you drive the car,
we had similar poroblems with older 4 cylinder engines
when you hold the power on the rollers @ a costant
speed you get stand off. If you do a sweep off at least
300rpm per sec no problem. One other thing springs to mind
check camshaft...
the first thing to do is check that the manifold is passing
on the air flow to the head, we have done a fare amount on airflow work on plastic intake/plenum and found as much as
20% restiction to flow so it may pay to test yours before you get to plenum volume.or make any radical change
Hi four - stroke performance tuning libary of Congess card no 2006921754. page 286 to 289 covers optomising 4-1 then
optimises steped headers from dyno figgers next step would be transiant response.
you would be better advised to go to a shallow valve angle so,that you keep good combustion. Flater piston crowns should give much more compleate burn usless you have a bad short side radius which is giving you bad tumble you are better keeping the chamber flater relitive to the piston
and keep...
Hi although you state that you are using trimetal bearings,
I suspect as its MGB based that they are infact A material
sinterd ali, which have a much lower load abilty and poor imbedabilty. With lead overlay Bearings hard to find try one of the new matrials like aluglide 810 an aliminum silicon...
may be stating the obvious but do you have clearance on both
exhaust valves?. What kind of base circle radius are you using, do you know the lift per degree on profile, what have you set your seat pressure to and your over the nose rate, also what is your valve mass weight.
Clibration on low impeadance injectors at high duty cycles
is poor and influenced buy voltage change,injector offset
is also difficault to set accurately and as a consequence
when using large injectors at low duty cycles it becomes
a balancing act to keep it in tune over any peroid of time...
Hi talk to Del West for hardware. And we have used OMEX TECHNOIGLY 710 Ecu to control the hardware developed to control; latest Honda systems this is fully mapable not just an on off switch Contact there systems enginer Andy Cornock.
