NVRAM 11p tuning discussion thread.

[Deuce]

of course, hit me up with whatever you need

You need to check your messages more often.
I sent you an idea 3 days ago.

 

[someguy360]

You need to check your messages more often.
I sent you an idea 3 days ago.

Hey I'm a pro at Whatsapp

Next thing I'm focusing on in the tune is the cold start. While it idles fine after getting the IAC to coolant temp offsets right etc it's still a pig in winter weather.

It idles fine on a cold start but if I touch the throttle it just splutters until it's up to about 45-50 degrees, which if I want to make a speedy getaway to a cars and coffee without waking the street up on a sunday morning I have to sit there for a good 3-4 mins warming the thing up in this winter chil or try and splutter it down the road until it wakes up.

AFR seems to sit at around 12.5ish on cold idle until it gets to around 30-40 degrees coolant temp. Theres not really too much else other than AFR/coolant offset and IAC for cold start parameters, not sure if I should be trying to go a little bit richer for the cold offset?

Not really sure where I should be looking at this point, the cams not that big that it should be such a pig when cold.

 

[Deuce]

Hey I'm a pro at Whatsapp

Next thing I'm focusing on in the tune is the cold start. While it idles fine after getting the IAC to coolant temp offsets right etc it's still a pig in winter weather.

It idles fine on a cold start but if I touch the throttle it just splutters until it's up to about 45-50 degrees, which if I want to make a speedy getaway to a cars and coffee without waking the street up on a sunday morning I have to sit there for a good 3-4 mins warming the thing up in this winter chil or try and splutter it down the road until it wakes up.

AFR seems to sit at around 12.5ish on cold idle until it gets to around 30-40 degrees coolant temp. Theres not really too much else other than AFR/coolant offset and IAC for cold start parameters, not sure if I should be trying to go a little bit richer for the cold offset?

Not really sure where I should be looking at this point, the cams not that big that it should be such a pig when cold.

Maybe try it leaner and see if it gets better/worse/no-change.
I've always wondered why mine is quite lean on warm up and if I should change it, but goes fine so hesitant to change it.

 

[someguy360]

Yeah I wasn't sure which way to tip the scales on rich or lean, as too lean when cold can cause it to struggle and so can too rich.

I've commanded 11.5 at cold start in the AFR to Coolant Temp table, which hasn't made much difference so I'll try leaner tomorrow and see what happens.

 

[Immortality]

I believe that comes back to the Charge Temp tables in the tune that adjust the fueling based on air temp and coolant temp.

edit:We put one in Duece's tune that should be more suitable to his COME intake manifold. I've not seen one to suit a dual plane manifold. I might have to have another search for a more suitable table as the factory banana's manifold was really a hot air stove type intake and the table will be way off for a more traditional dual plane one.

 

[someguy360]

I believe that comes back to the Charge Temp tables in the tune that adjust the fueling based on air temp and coolant temp.

edit:We put one in Duece's tune that should be more suitable to his COME intake manifold. I've not seen one to suit a dual plane manifold. I might have to have another search for a more suitable table as the factory banana's manifold was really a hot air stove type intake and the table will be way off for a more traditional dual plane one.

Awesome, thanks mate.

I'll have a bit of a play in the meantime and see if I can at least make it a little better.

It definately wasn't as much of an issue over summer/autumn but now winters hit it really hates load when cold.

 

[Immortality]

Grab a copy of Duece's tune and maybe try his charge Temp - %age of coolant temp table and see what that does.

Do you have an airgap style manifold?

 

[someguy360]

Grab a copy of Duece's tune and maybe try his charge Temp - %age of coolant temp table and see what that does.

Do you have an airgap style manifold?

Yeah I do have an air gap.

I'll shoot him a message, I'm haivng a look at a couple I have in my repository with decent sized cams and single planes and the difference between the two tables is insane.

Definatley where my problem lies I suspect.

 

[Deuce]

Yeah I do have an air gap.

I'll shoot him a message, I'm haivng a look at a couple I have in my repository with decent sized cams and single planes and the difference between the two tables is insane.

Definatley where my problem lies I suspect.

Info on its way to you.

 

[someguy360]

Ok ran Deuce's charge temp tables.

Didn't seem to make it any better, in fact it was slightly worse I feel. AFR's dipped down to the 10.0 with some throttle when the engine was dead cold. If I hold the car at around 1500RPM for 45-60 seconds or so it smooths out (reminds me of my Quadrajet days) and then it's all happy days, it's just that first couple of minutes of run time that sucks.


Just going to require some tweaking I guess, thats the worst start about cold start tuning, you only get one shot at it being cold each try.