F-Body Europe

SRZ · **Posted:** Thu May 30, 2002 8:01 am

Well after putting the cats back on 2 days ago I get the cherry glow effect. Tested my fp and it was @ 44 vac off. Reset and turned it down and managed to get one cat to stop glowing. Driver side still will glow after 10 mns of warmup. I'm thinking of swapping the cats around and see if it does on the other side. If so then I know it's clogged if not what could it be?

What I'm really trying to figure out is how lean can you go before detonation? Better yet what does detonation sound like so I know when I start dropping the fp? Couple of 93 guys are going as low as 33 w/ vac line on. I think I'm gonna shoot for 34.5/35 and see what happens. I just want to stop glowing so I can at least past visual. Audible is something different and not a real concern right now.

Hawk · **Posted:** Thu May 30, 2002 8:08 am

Pinging is how it starts. I run mine rich rather than lean give up some Hapees but much safer it is hard to blow a rich running engine however a lean engine will blow pretty quick. Glowing cats are normally plugged or defective and rob large amounts of power.

Roy · **Posted:** Thu May 30, 2002 9:24 am

John your mixture is still too rich . I know you that already.

I am gonna throw some stuff out there for you.
Have you set the FP to stock to see if that helps.
ARE you running MSD box ? If so is your plug gap wide enough to take advantage of the MSD (.050 gap).
Also have all cylinders been hooked to a oscilloscope to check on the misfires. I do know on a cam like yours you will have a few. But it shouldn't be from the secondary side of the optispark. Alot of misfires happen because of spark flameout. Plug cables all tight and the resistance in the cables is with in limits. If you are running resistor plugs check their resistance. It also might be one or two fuel injectors that are dribbling fuel when closed.
How are the O2 sensors doing ? Connections clean no burned wiring. Can test for 14.7 stoichmetric a/f ratio at an idle.
Got any intake manifold leaks ?
Do you have a MAF if so any air leaks on the back side of the MAF.

Do you have a way of pumping more air into the engine exhaust ? I donot know if your engine came with a air pump.

Cold start enrichment circuit. Is it operating properly. when looking at COLD start also check for open loop and closed loop operation. Cold start is always open loop. Closed loop happens when certain conditions and engine parameters are met. Dave (CK) dwelled on this earlier .

Just for giggles What size is the camshaft at
.050 lift
duration
lift
LSA
Intake LCA
exhaust LCA
degrees advance or retarded.

you may have to run hollowed cats because the overlap intake and exhaust valves is too great.

Any body else?

SRZ · **Posted:** Thu May 30, 2002 10:11 am

Quote:

John your mixture is still too rich . I know you that already. Yeah I know.

I am gonna throw some stuff out there for you.
Have you set the FP to stock to see if that helps.
Stock setting is too rich they'll glow in less than 5mns doing that.
ARE you running MSD box ?
Accel 300+
If so is your plug gap wide enough to take advantage of the MSD (.050 gap).

Gapped them @ .040 maybe should've left them at .050

Also have all cylinders been hooked to a oscilloscope to check on the misfires.

No misfires.

I do know on a cam like yours you will have a few. But it shouldn't be from the secondary side of the optispark. Alot of misfires happen because of spark flameout. Plug cables all tight and the resistance in the cables is with in limits.

Yes

If you are running resistor plugs check their resistance. It also might be one or two fuel injectors that are dribbling fuel when closed.

How are the O2 sensors doing ?
Last checked they were reading 128 blms w/ 39 psi. Then after tinkering I haven't had it scanned so maybe I'll go back to 37-39 to be safe.

Connections clean no burned wiring.
Nope.

Can test for 14.7 stoichmetric a/f ratio at an idle.
Not until next wk will be able to test that then.

Got any intake manifold leaks ? No leaks

Do you have a MAF if so any air leaks on the back side of the MAF. No maf speed density.

Do you have a way of pumping more air into the engine exhaust ? I donot know if your engine came with a air pump. air pump removed.

Cold start enrichment circuit. Is it operating properly. when looking at COLD start also check for open loop and closed loop operation. Cold start is always open loop. Closed loop happens when certain conditions and engine parameters are met. Dave (CK) dwelled on this earlier .

Just for giggles What size is the camshaft at
.050 lift
duration
lift 544/560
LSA 110
Intake LCA232
exhaust LCA 242
degrees advance or retarded. 4 advance

you may have to run hollowed cats because the overlap intake and exhaust valves is too great. Got guys running bigger w/ cats.

Any body else?

Thanks Roy and Bruce. But do you know a ball park figure what's considered leaned to induce detonation?
Must be 33 or under you think? How much abuse can a cat take? So when saying clogged does that mean fuel is building up down there and heating up. I don't have no headers glowing so I'm not lean that's for sure.

Roy · **Posted:** Thu May 30, 2002 10:39 am

Dam John

That is one healthy cam . That 110LSA combined withthat duration is killer. You will have your work cut out for you especially with sPeed Density. SD isnot as forgiving as a MAF when it comes to cams.

Now for a cat to get clogged it has to be superheated . The easiest way is a rich mixture. The second way is a Lean mixture . What usually happens is the platinium catalyst gets super heated and can actually melt when it starts to melt it will plug the honey comb structure of the catylyst. Then you get a blockage. Another way is that catylyst breaks up and creates and obstruction leaving the cat.

Connections clean no burned wiring.
Nope.
So does that mean the conections are dirty and the O2 wires are burned?

SRZ · **Posted:** Thu May 30, 2002 1:51 pm

Wire and plugs, connections in perfect working order. Superheated hu? Well guess I got a clogged cat then because I was super rich 80+ psi when I drove the car home after installing the flp's last yr. 20 min drive and cherry red. Not to mention the last couple of days trying to get the fp down and looking underneath only to see them start glowing again.

But like I said it's just one glowing now. 325 a pair from flp so I may go that route real soon. Like I said though I could see straight thru them before putting them on though. Maybe that doesn't matter and the honeycomb looked fine. I'm gonna cut it down today and and see what happens (fp), Thank goodness for the ORP's

Yeah it's a big cam but I've seen bigger believe it or not and hyd at that!
Thanks Roy.

Roy · **Posted:** Thu May 30, 2002 3:51 pm

If you can see through the honey combs then it more than likely good. I like to hold them up to a bright light to check.

Have you pulled the plugs on the glowing side and looked at them under a mag glass and light to see for any fuel washing.
Also if your privy to a pyrometer be it infared or contact you can check each header pipe and see what the temp is. The low temp would be the culprit cylinder . If there is no low temp check the other side and compare sides. A low compression cylinder will cause a rich mixture also. I hope it is not that.

SRZ · **Posted:** Thu May 30, 2002 4:56 pm

I've got access to a digital temp guage so I'll try that when I get home. Haven't checked the plugs since putting them in last wk. I'll pull a few out and see what they look like.

I'm pretty sure it's not a low compression cylinder at least I hope not. That would ultimately blow chunks aka suck major @$$!

Thanks.

ChickenKiller · **Posted:** Thu May 30, 2002 9:55 pm

Dude when you gonna bring that car in to see me ??? You're gonna blow it up !!!

Careful don't get too low on fuel pressure. Too low and the fuel won't atomize well enough and all the fuel won't burn. Come see me man.... I'll use my Ford tools to fix it for ya.

SRZ · **Posted:** Fri May 31, 2002 6:32 am

I'm coming by today. Not like you'll read this you'll be at work!

Well I took the cats off last night and double checked them and I can see right through both. The one that gets hot smells like a gas slightly. I did the temp reading and that cat got above 500 degrees! I thought normal op temp for those things was like 300-350? The other cat was like 300 and climbing but not to the point where it would glow I believe.

Then I did a reading on the primaries and the 1,7,2,8 read between 160-170 while 3,4,,5,6 read like 250. Why such a huge difference? Pulled 2 plugs on the driver side and the electrode on one was white or close too it. Meaning too hot while the other looked normal/tad rich. So I regapped them to .050 just those too and bumped the fp back to 41 vac off. I know I know. Didn't have time to do all 8 got to go to spang today.

I didn't get on it this morning for fear of screwing something up but it still smells like pure gas out the back w/ ORP pipes. She doesn't seem to be as responsive before playing w/ it all last wk. So I'll bump the fp another 2psi and see what happens. Next wk I'll redo all the plugs and swap the cats from side to side and see what happens.

Bruce if you read this how the hell you gonna pass insp w/out cats? I need the same hookup just in case!

sinistersi · **Posted:** Wed Aug 07, 2002 4:49 pm

And for the record, pinging sounds like someone throwing rocks into your intake. Listen for it and act quickly if you hear it! Is there any kind of a safeguard system for your car. It will detect pinging before you do and it will retard your engine to prevent it. If you wait to hear it you may have already blown your engine.

F-Body Europe

Glowing Cats.........help bitte'

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