Need advice on my turbo air-fuel ratio's - are they safe?

[ON_N20]

Hey guys

I just got my DSM turbo set-up up and running in my Accord. Im running Crome Pro on a P06 ECU, and I also have an Innovate LC-1 wideband and XD-16 gauge for logging AFR's. I created my basemap and started doing some fine-tuning and got it to run great overall, but I'm still running rich when I'm off boost and at idle. I would make adjustments, but my laptop just crashed on me, so I'm unable to make any further adjustments at the moment, but my concern is driving the vehicle with it running really rich at idle/low-load crusing, if that will cause any long-term damages or issues?

Obviously I plan on getting the map finished up, but I just need to know if my AFR's are safe or not while driving in the mean time. My AFR's under boost are about 12.5:1, and idle/low-load AFR's range from as low as 11.5:1 to 12.5:1. I know the ideal AFR's at idle are about 14.7:1, and crusing about 14.7:1 or slightly richer to be safe, correct?

So what do you think, is an off-boost AFR of approx 12.0:1 going to cause any long term issues?

My main modifications are as follows:
F22A1 with Arias 8.2:1 CR pistons.
Little 14b turbo currently at about 6lbs boost (keeping a close eye on intake-air temps).
680cc Precision injectors.
Walbro 255lph fuel pump / stock fuel pressure regulator.
Front-mount intercooler, 2.5" charge pipes.
Chipped P06 / Crome Pro / Ostrich 2 emulator / USB datalog / Innovate wideband.

[Gtseviper]

hope this helps...was asking the questions...and these are the reponses I got

http://www.cb7tuner.com/vbb/showthread.php?t=159699

[ON_N20]

hope this helps...was asking the questions...and these are the reponses I got

http://www.cb7tuner.com/vbb/showthread.php?t=159699

Thanks I actually searched and read that thread before I posted

That confirms my knowledge about figuring out the correct AFR's for under boost as well as off-boost. However my original question was targeted more at what the possible side effects are of running an engine very rich in an off-boost section for an extended period of time.

I figured the plugs would foul out quickly, but I didnt care about that, theye're cheap to replace. Ive even heard things like an overly rich AFR can "wash" the oil off the cylinder walls. Another concern of mine is that the excess unburnt fuel could cause my catalytic converter to meltdown on a long highway drive or something. I was planning on about a 100 mile drive tommorow, but I dont want to do so if running that rich will cause any long term problems.

[rexload]

680cc injectors for a 14b? I hope you are planning on upgrading.

anyway, you are saying your idle/cruising AFRs are around 12.0? That is honestly not that rich, it won't cause any problems if you go on your 100mile trip.

just don't leave it that way, tune for 14.7-15.0 at idle/cruising, or you will be just wasting fuel.

also, what do your timing values look like?

[ON_N20]

680cc injectors for a 14b? I hope you are planning on upgrading...also, what do your timing values look like?

Update

Yes I do plan on upgrading the turbo, or at least the turbo compressor and housing. I used a fuel injector calculator and figured that the 680cc's will work fine now and still have enough left in them for my future power goals.

I cant remember my total timing values, but I do have it set to automatically retard by 1 degree per 1 pound of boost right now.

Anyway, I just got back from my little trip and didnt have any problems with the low air fuel ratio's, I just used a ton of gas.
The only real problem I had all night was the charge pipe blowing off at one spot because of a cheap charge-pipe clamp. As soon as I get my computer up and running again I'll work on leaning out the off-boost portion of the map, and get it running smooth and fuel efficient again, but with moar power!

[Ander]

Did it blow off again on the way home?

[ON_N20]

Did it blow off again on the way home?

Nope I didn't have a single problem the whole way home, and I went into boost plenty of times, go figure

[rexload]

Keep in mind that those fuel injector calculators tell you to enter a Fuel Consumption number of .60+ for turbocharged engines when in reality Honda engines are way more efficient.
In fact, small Honda turbocharged engines will have a Fuel Consumption number of .40 sometimes (which is less than whay they are telling you to use for naturally aspirated engines)

Your 680cc should be good for over 400hp at the wheels.

[Ghetto_CB7]

Short answer

A very short answer to your question is to pull a plug and look at it...

Any signs of preignition or detenation and you know you did something bad.


Also I should note, expecially when running on a not so good tune in low rpm's to not go into high load.

It is (from my understanding) actually more dangerous (combustion wise) to be at low rpm and high load then high rpm and high load.

So be carefull, one of my friends was doing pulls in his boosted teg that is currently running dirt rich, and I pulled a plug. It had signs os of both preignition and detonation on it.

Of course you said your idle was the only thing off, but I am just throwing this out there.

good luck

[h22sparkle]

get some real couplers and some real pipes with t-bolt clamps

[ON_N20]

Thanks for all the replies and advice, I did finally get the computer up and running again and was able to fine tune things. At first I couldnt figure out how to lean out the vacuum portion of the map without affecting the boost part of the map, but I ended up just tuning the vacuum part of the map with the charge pipe disconnected untill i got that all good, then added the boost part of the map again, and just played with the turbocharger efficiency section to get the AFR's right for everything.

So far so good and I finally have some sane mileage numbers once again

get some real couplers and some real pipes with t-bolt clamps

Yes I do have all reniforced charge pipe connections and t-bolt clamps now. I was one short at the time I first posted and of course that was the one to blow off and cause me problems.

[brsteinbach]

OT but we need to meet up again. That was pretty cool man. I still need a solo ride!

[ON_N20]

OT but we need to meet up again. That was pretty cool man. I still need a solo ride!

Yeah we'll definatly have to meet up again.. and I still have your friends ratchet in my car I'm sure he's waiting for me to give that back. Yeah i totally forgot I never gave just you a ride haha.

Im running about 10 lbs of boost now, and as soon as I get the GM 3 bar MAP sensor in I'll probably turn it up a bit more. I have to be carefull when Im turning up the boost now though, because that small turbo will start generating alot of heat at those higher boost levels. So far my intake temps have stayed less than 130 degrees at WOT, which I believe is still a safe level.

The car still has a pretty good shake at low RPM's though so I think im going to do a compression test and see what the numbers are before I turn the boost up any more. Ive checked the spark plugs and I dont have any signs of excessive heat or detonation . I know the downpipe is contacting the subframe in one spot due to clearance issues , and I dont have the torque mount anymore due to the turbo set-up, so hopefully thats the only reason I have excess vibrations, and not a more serious engine or tune problem.

EDIT (again!) - I just did a compression test, they were all at around 150 PSI and all four cylinders didnt vary by more than 4 PSI!! So apparently my bottom end is still rock solid . Keep in mind of course I have an 8.2:1 compression ratio so my low compression readings are right on in this case. More to come... I think i need a MRT

[brsteinbach]

Hell Yeah man! I'm glad everything is lookin/going good. What are you doing tommorow night? I know quiet a few of us are going to be out.

[ON_N20]

Hell Yeah man! I'm glad everything is lookin/going good. What are you doing tommorow night? I know quiet a few of us are going to be out.

Hmm I havent thought that far ahead yet . Im not sure if I feel like burning up premium gas for 110 miles to get me back and forth to work haha! I think I might wait just another week and play with the tune some more before I come down again- it wont be too long before i'll be taking that green Evo on a run for its money .

But yeah the AFR's are pretty good right now and my fuel mileage is pretty good again. I checked the plugs and did that compression test tonight and everything checked out good.