'big cam' idle - is it latency

brett_32i · Post by **brett_32i** » Thu Jan 29, 2009 11:09 pm

after a switch to nistune ecu set for my new injector size, the engine idles great from cold but once it warms up it develops a 'large cam'

it still drives fine, just a crazy idle, which kind of sounds cool.

so should i start by increasing the latency

i have read a few posts about latency but didnt find a reference to my symptom

bemis · Post by **bemis** » Fri Jan 30, 2009 5:19 am

Sounds like your AFRs are very lean at idle which is probably because your k value is set improperly.

Do you have a wideband installed?

Are your upgraded fuel injectors impedance matched with the ECCS? And I don't mean the use of resistors . . .

Raise your K value by about 10% and see how your idle changes.

brett_32i · Post by **brett_32i** » Sun Feb 01, 2009 6:29 pm

when i purchased the board, i assume matt just altered the injector size to suit my new ones.

both new and old injectors were low impedance.

software is coming soon so i will be able to start playing, just wanted to get an idea where to start.

Matt · Post by **Matt** » Sun Feb 01, 2009 10:24 pm

I always put in a factory ROM image onto the board unless you've specifically asked me to adjust it for you

Software is available on the website so you should be able to plug in and adjust it now

brett_32i · Post by **brett_32i** » Mon Feb 02, 2009 11:00 am

thats cool matt, remember i specifically asked for the na maps instead of the turbo maps.

brett_32i · Post by **brett_32i** » Tue Feb 10, 2009 5:57 pm

so is there any detriment to running at idle with low latency values?

will my 'big cam' be so lean as to be causing damage?

i have heard of people with ls1 edit being able to dial in a cam at idle. is this how the do it?y

datsunboy · Post by **datsunboy** » Wed Feb 11, 2009 12:08 pm

you cannot dial in a cam with the engine running at any rpm.....unless you have some sort of awesome gadget that allows you to adjust the cam gears while running!

brett_32i · Post by **brett_32i** » Wed Feb 11, 2009 3:44 pm

sorry, you mis understood, my mistake.

apparently guys with ls1 edit are able to program a rough idle so it appears the car has a large cam.

this is what i meant by dialing in a cam (with the keyboard) knowing exactly what is required to dial in a cam shaft.

so, do they just adjust latency to achieve it??