Hey guys this only happens on cold start but as it warms up it'll balance out to a 14.8-15.3. Wot is at 13.0- 13.4.

On cold I know its suppose to run rich but is it suppose to run that rich and spit some I guess it's black extra fuel out the exhaust from running rich on cold start? but everything else is fine.

 

Oh and my motor is a complete gsr engine with

Usdm type r pistons
Sk2 manni
Blackworks cams
Supertech dual valve springs and retainers
Blox 2.5in velocity stack
Vms adjustable fpr
Accel high output ignition coil
Ngk spark plugs and wires

 

Is it tuned?

 

blackworks cams huh...?
What injectors?
What are the specs of those cams?
And as stated above, tuned?

 

Normal for cold start up

 

Oh sorry I meant cam gears but set to stock settings, just stock gsr cams. And it's only chipped from phearable on p72 ecu.

 

Oh and for injectors I am using stock gsr injectors.

 

Ditch the fpr. Post start and cranking trims could use a little work probably, if your issue only exists for the first 30-45 seconds the engine is running. Iat/ect offsets might need some work too, but honestly your manifolds are mostly stock and stock settings shouldn't be far off. Really it's all pretty normal on cold starts.

The dripping is more likely water re-condensation mixed with soot as the exhaust dries out and then cools on leaving the pipe. You would have to be richer than 11.9:1 before you start dripping raw fuel.

 

What about the raw fuel spitting out my exhaust but only if I rev on cold start?

Also I wanted to mention that my o2 has replace with my wideband o2 sensor. So I've rewired and soldered my o2 wiring on my ecu so it won't throw an cel. Could this b the cause of it?

 

Didn't really think about the condensation makes since though. So I should ditch the fpr? I had to adjust it up on fuel to make it run good on wideband.

 

so here is a slightly on topic comment: the ecu is running a ton of timing when it first cranks over when cold, does that help burn off that fuel better and make it a non issue?

i know my b20 with an integra ecu and factory o2 has the first 10 or so seconds afr around 11 then it comes into the mid 13's until it warms up and runs off the o2's. i need it to run at that fuel pressure or it is too lean at wot

 

Its not "raw" fuel, its condensation. Its Normal. Proper heating of an engine starts with cold starts, it'll be rich and gradually lean out, you don't want to heat the cyl too fast, otherwise **** expands faster then other parts and it can cause issues, down the line.

This is all normal.

 

Technically yes to your first part.

Using a FPR to control AFR is like 1990 old school style.

 

my cold start is 11.8-11.9 on 1000cc grams. my hot idle is 13.0 ish. If i try to idle what is said to be normal on the internet, i get lean pops. the amount of fuel it takes to change the afr at idle is very very low. so 12.0-14.7 isnt much of a difference in fuel consumption at idle. i will typically just listen to the engine and give it what it wants. not every engine is the same.

if you were spitting raw fuel out of the exhaust, the engine would run like crap.

 

^ Thx you~~

Btw, on E10, which is 93 pump gas, with 10% E, Stoich is 14.2, not 14.7, which would mean all the target AFRS would need to be adjusted. Just because 14.7 is the norm, doesn't mean its the exact point in which your motor likes it.

My big motor, big cams, likes 13.4-13.8 AFR at idle, with 19 degrees timing at idle. Anything leaner and it sounds like ****.

 

im curious, if your hot idle is in the 13s AFR ... do u aim for 13s in part throttle/cruising as well, or back to the 14.3-14.7 range? (in the particular setups you guys are talking about)

 

Cool good info guys. So is 14.7 too lean on 93 gas?

 

Also I wanted to add I do get a lil poopin noise kinda like my spark plugs is getting blown out ( or mayb could b the fpr) on low rpm gears at about 2k rpm to 3.5k rpm. No problems at high rpms though.

 

Obd2 car I need to pass inspection. Its just temporary


Op- its not that 14.7 is too lean I think its more that not wvery engine likes that afr at idle and its not the end of the world if its a bit richer

 

The general afr to aim for is(all motor)

14.7 idle
12.9-13.3 wot
14.7-15.5 cruising

normally cruising, you tend to put no load on the car.. these are just targets and aren't the end all be all. I've h22's I tune like 12.5 wot and make more power then @ 13.5 afr. I've had some cars that like 13.4 and make more power then running 12.9. Its all on what the motor wants, which is why a track and dyno are very important.

I normally shoot for a happy medium when tuning for partial throttle.. as long as the car isn't breaking up, its fine, you really have no load when cruising on the car.. on my personal cars I normally shoot for 15-15.8's cruising that's just me.. others stay around 14's or higher 14's


every car will idle differently, big cams with little vac will not like 14.7 afrs. you'll also need more timing at idle, 16 or 16.5 wont be the end all neither.

 

Lean, is a term.. 14.7's is stoich for idle, its fine.. don't get so caught up in numbers.. if it idles smooth and steady, I wont worry. worry about AFRS if the car is breaking up or at wot your in the 14's, then worry.

 

I also wanted to ask how psi can my stock injectors hold? I'm at 50 psi according to my fuel pressure ( mounted on my fuel filter ).

I honestly think this motor can push a lil more power out, but I don't won't to overdue it on my injectors. I also at 16* btc, I believe I can advance it more as long as I don't hear no pinging correct?

All this knowledge is very helpful for and other people
Thanks everyone

 

No.

 

yea thats what alot of the stockish setups shoot for. my question was more towards the specific setup that you have idling at 13.4-13.8. was that setup able to cruise on 15-15.8's? do u have columns 4-5 in the 15's as well?

 

When I was daily itbs, it was richer on cruising.

on a manifold it could be leaner, I believe that had something to do with fuel distribution.

My racecar, idles @ mid to high 13's. When I was daily driving it, yea it was cruising in mid 15's or so.. I have columns as they go up, start to go richer.. you'll find leaner will give more response, rather then dumping fuel on tip-in, you have to gradually get there, or I try to get there.

here's a pic of the low cam map for your question, the car is on c16 now, so the map is adjusted for such, the partial maps haven't been touched since the fuel change, some of the ign has been, but this car rarely sees below 5K anymore.. and I have a good bit of nitrous on it as well.