Hello Everyone! I am new to LS engines and not all that knowledgeable about tuning. I put a brand new LQ9 Texas Speed built engine in my 56 Belair setup for Speed Density.. I have some mods to it, Cam 232/236 .600/.600 112LSA, Bored .030, PRC 225 Heads, Fast LSX 92mm Manifold. I have had a mailorder start up tune done at 2 different places (1st place went under) It is runnin extremely rich and fowling plugs after only 10 or 15 minutes of running the engine. I have not driven the car yet (still working on things) I have all the sensors hooked up and have checked for codes. So far there are none. I have long tube headers hooked up with the O2 sensors installed but i do not have mufflers and tailpipes installed. Could the exhaust not being installed be causing this issue? Here are some pics of plugs after only 15 minutes of running at idle. Should I bring it somewhere and have it tuned? Where do i start?

 

If you don't know how to tune an EFI engine, then you're better off taking it to a tuner.

 

Woah woah woah whatever happened to gotta start somewhere

If you don't care enough though yeah take it to a tuner

 

Right now i don't have the time to really dig into learning how to tune. It is definitely on my list of things to do but this has been a complete frame off restoration that has taking up what little free time i have. Just looking for advice until i learn enough to do it myself. Nearest engine tuner is about 1 1/2 hr away. Is a start up tune generally good enough for it to run, idle and drive it for test purposes?

 

I mean you can purchase a mail order tune and it will work 100%. Now keep in mind it won’t be completely min maxed but it will work and be good enough for almost every application. Most tuners will even work with you to get some logs done and try to tweak it a bit

 

Thanks Shakenfake I know that its not an optimal tune but was hoping for at least a test driveable tune. Again, new to the LS engines wasn't sure what to expect. I will call the company that tuned it and talk with them about checking it over again.

 

Didn’t read you had a mail order already done.

Yes I suggest take it back and say well wtf. Fouling my plugs man.

Now they may say you need to do some hard diagnostic and it might not be in the tune which is true and certainly could be the case. No it is not your exhaust causing fouled plugs though

 

I'm in no way a tuner but what plugs are you running and what's their gap? I'm curios if stepping up to a hotter plug would help and I assume you don't have a wideband sensor installed or any tuning software so you can log data?

 

01CamaroSSTx I have NGK TR55ix plugs gapped at .60 which is what they came gapped at. I have narrow band O2 sensors but i did put a bung in for wide band hook up. No tuning software yet..it is on the list for the future though.

 

Try TR6 plugs

 

I would try a TR6 or TR7IX plug and shorten the gap .035 -.040 to see if it helps but if the tune is way too rich it may not do any good.

 

Do all the plugs look like that? You didn't specify nor post a picture of all eight so I am assuming they do.

If they do I think it is more the tune than the plugs.

 

^^^^THIS. Plugs alone don't richen/lean the A/F.

 

Saying that though I still would recommend stepping down the TR6s. They will be the better plug for your application. If I hadn't spent $40 on my Iridium IXs I would have swapped them out for the TR6s when my tuner did a look over of my logs and told me to switch lol

 

You CANT run open headers with O2 sensor. It will read lean and max out your fuel trims dumping fuel. You will either have to install exhaust or unplug O2 sensors.

 

??? I am assuming his tuner tuned for no rear O2s. When he says he has his O2 sensors installed I am guessing he means his fronts.

If you are saying he can't run open headers with *any* O2s then I'd say you are wrong.

 

If you run an O2 sensor within a foot of the end of an open collector, it will give false readings EVERY TIME. And yes, this means the front, or in many cases, only sensors

 

So basically it is the tune.
Plenty of guys run open headers. I understand that yes the readings will be screwed but you can fix that in the tune.

 

G I’ve been thinking about what you said and I changed my mind only if he doesn’t have a y-pipe. If he has a y-pipe he should be fine and this should have no affect on him

 

Yes plenty of guys run open headers w/O2 sensors, but there is no ACCURATE way of compensating for the air reversion pulses hitting the sensors.
You need uncontaminated pure exhaust for O2 sensors to read properly. No other way. You're shooting in the dark, blindfolded otherwise.