420A too much fuel, done my research

[newdsmtnr96]

From innovate motor sports....
<br>

The measurement Lambda is the actual air fuel ratio over the stoichiometric ratio. A Lambda
measurement of "1" equates to the air fuel ratio of 14.7 (for gasoline engines). When Lambda is
less than 1 the engine runs "rich", i.e., unburned fuel exists in the exhaust stream. If lambda is
greater than 1 the engine runs lean, i.e., free oxygen (02) is present in the exhaust. Depending on
the engine, maximum power is typically delivered when the engine runs slightly rich (for example
at lambda values of 0.8 to 0.9 for most engines). This instrument provides a means to measure
the actual air fuel ratio or lambda in the engine in operation directly from the exhaust. For this a
special wide-band oxygen sensor is used to measure the lambda value derived from the oxygen
content (or lack thereof) of the exhaust gases.

 

[Car_guy_09]

From innovate motor sports....
<br>

The measurement Lambda is the actual air fuel ratio over the stoichiometric ratio. A Lambda
measurement of “1” equates to the air fuel ratio of 14.7 (for gasoline engines). When Lambda is
less than 1 the engine runs “rich”, i.e., unburned fuel exists in the exhaust stream. If lambda is
greater than 1 the engine runs lean, i.e., free oxygen (02) is present in the exhaust. Depending on
the engine, maximum power is typically delivered when the engine runs slightly rich (for example
at lambda values of 0.8 to 0.9 for most engines). This instrument provides a means to measure
the actual air fuel ratio or lambda in the engine in operation directly from the exhaust. For this a
special wide-band oxygen sensor is used to measure the lambda value derived from the oxygen
content (or lack thereof) of the exhaust gases.

And??.......

 

[newdsmtnr96]

just saying that 14.7 is suppose to be a stoichiometric ratio

 

[chris712vt]

yes at idle and cruising that may be optimal, but under heavy load when you're in boost you want it under 12.5

 

[Car_guy_09]

^^Exactly

 

[bullettdsm]

Paul/Mark/Car_Guy or whoever else - is there any difference between the blue top versus the black top 450cc DSM injectors other than they are from a 1g/2g? Isn't there a green top too or am I mistaken? Will any of them swap right in place of ours?

Sorry I forgot to get back to this.

Just talking to a DSM injector buddy of mine (he checks, cleans and resells injectors). He hasn't heard of a green top DSM injector either. The blacks and blues are both 450's. Don't forget there are 390's out there from the 1g auto's (these are I believe tan or grey).

MB

 

[chris712vt]

Thanks, I actually just bought a set of 450s so I'm looking forward to getting them installed with my SFMU and upping the boost a little.

I thing the green tops I was thinking of were ford injectors.

 

[Car_guy_09]

Thanks, I actually just bought a set of 450s so I'm looking forward to getting them installed with my SFMU and upping the boost a little.

I thing the green tops I was thinking of were ford injectors.

Yeah im pretty sure the green tops are for a mustang.

 

[turboglenn]

yes at idle and cruising that may be optimal, but under heavy load when you're in boost you want it under 12.5

ON an N/A engine you want between 12.5 and 13.2 during WOT.

ON a turbo car you only want to run as lean as 12.5 when you have race gas. On pump gas and anythign over 12 psi of boost you want to try and shoot for 11.5 at normal 16-20psi pressures and as far as going down to 11 or 10.5:1 for the higher boost levels of 20 and above...these are my general guidelines anyway which are derived from expoereince, other peoples expereience and a few more years of reading and studying other peoples setups ..not to mention ti's what most people run... I'm not trying to be a smart ass so don't take it that way, just trying to put the info out there for anyone who is reasing this and wondering a bit more aboutAFR's

 

[chris712vt]

thanks, yeah that's a better guide than what I said haha

 

[newdsmtnr96]

You must be logged in to view this image or video.

most recent vid.. at idle

 

[rstare]

What are those gauges?
The top one looks like AFR, second looks like vacumm/boost, and I cant tell third.
It looks a little lean at idle, what is your idle fuel pressure? I would bring it up some if I were you.
Looks good under boost though, might even be a little rich (that is if I am reading the numbers on the AFR gauge right, there really blurry)
How do you have your sfmu configured?

 

[newdsmtnr96]

Yeah first one is a/f 2 is boost 3rd is oil pressure. I did find out that my turbo downpipe keeps cracking because my stock cat cant handle the boost. So it provides so much pressure that it just cracks. Next im still trying to find out what to do about when it hits high rpms the valve cover breather pushes oil out. I also found out when taking my turbo off because seals are going bad that it wasnt making a full seal. 2 bolts were missing. Must have poped out. I want to really thank all the dsm people for helping me out. I had alot of questions here. Finaly i have the dream i always wanted. but i need to get a stiffer spring cause my car when fuel pressure is high it boggs it down a little then when 2800 rpms hit takes off like a bad outa hell..

 

[Blitzeclips]

\Next im still trying to find out what to do about when it hits high rpms the valve cover breather pushes oil out.

Try running an oil catch can. Might alleviate the additional pressure built up.