Wideband vs Spark Plugs??

[DrBrown]

I have not been on the dyno to check out my A/F lately and the car seems to be acting up a little bit. My plugs look nice and tan or even brown on some of them. I have 2 stages colder NGK plugs gapped at .034". When I hit about 8-9psi the car just feels like its dying or bogging down. Its not detonation because I have way more than enough fuel flowing and the plugs prove that. I just dont have a wideband on my car so Im a bit confused by the whole situation. So I was curious for those of you who do have a w/b what color are your plugs when running around 11-12:1? Last time I dynod I was at 10:1 hahaha and the plugs looked the same as they do now, BROWN! So if anyone knows what their plugs look like and know their correct a/f let me know what you think. Thanks!

-Dan

 

[gsxtacy]

Didn't notice you had a NON-DSM, what are you running specifically? Honda?
Check you factory specs and then understand that a Turbo car requires ALOT less gap to FIRE properly, because of the Forced Air.

Experiment until your flame doesn't blow out.
I have seen people run as little as .020", from your description of your problem, Gap definetly sounds like your problem. My plugs run Crisp White...to kinda Dull grey. Depending on when I pull them.

Here's another good tip: Do a really hard Full Boost pull in 3rd gear and turn the key off when you reach your shift point to 4th.
Pull your plugs and look at them. I gaurantee you can nearly guesstimate your A/F ratio based on this alone. Takes awhile to learn but over time you'll be a pro. Get a good magnifying glass to inspect with also.

Dsm's follow this:
If you look under your hood at factory specs on Plug Gap. Its NO WHERE near .034".

It says .028-.032

I get flame blow out with anything over .030

I run 18 psi (Big28) on my 98' GSX, and I have BR7ES NGK Copper plugs, try .026-028 and see if you lose your stuttering.

Good luck

Gsxtacy

 

[DrBrown]

I dont feel safe boosting to 80mph in 3rd and just shutting the car off and choking the oil supply feeding the turbo. I have not had very good luck with turbos the pat 2 years and Ive fried a few. I dont need help doing it again

My car is a 95 Probe GT which is a 2.5L V6 24-valve 9.2:1 compression. I am running about 10psi now on a smallish T04B and the plugs look like this:

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They seem to be burning nice and smooth. My stock spark plug specs are to gap at .044" for the N/A setup. Well obviously thats out the window and Im already running 2 stagees colder (7 range) and they plugs burn very clean. I have them set at the same .034" still and I dont think its having any major issues. I cant really understand how to read plugs I guess. The base is black like its not burning it all off, then one side of the elctrode is dark brown and the opposite side is barely tan like its lean. But I think Im in the ball park. I dont think I should go below .030" at all because Im not running enough boost to blow out the spark...but I dunno. Thats where Im at now and all seems well so far. The wideband will help the tuning process immensely!

 

[gsxtacy]

my car would stutter during the intial boost peak and then pull like crazy as the boost leveled off at the set point ( hehe I always have had 1-3 psi spike ), well I changed the gap to less than recommended and wha-laa, straight crisp spark.

Good luck to you.

Gsxtacy