Larocca's doesn't know how to fix my 93. WTF????

I will try and make this as short as possible. Larocca's still has, and have had my car for almost the entire summer. My problem being glowing catalytic converters.
I bought a used 306 shortblock without cam, Pro-M 75MAF, and 24# injectors from a dude in my town. Block had approx. 13,000 miles at the time. About a month later I bought his used Comp Cam that he had in the block before selling it to me. I bought a bare set of Roush 200 cylinder heads and had a machine shop assemble them to complete with all Manley parts. They ported/blended the bowls and chambers and milled them .040". They also assembled and installed the motor.
Prior to having this motor dropped in my 93 which was basically stock at the time, I put on MSD and a CAI. Keep in mind I had the stock converters on at the time. So far so good (no problems). Shortly before bringing my car to get the motor dropped in I swapped the the Hpipe for an offroad one.
I finally get the motor put in and eliminated the smog pump. My car exhaust smelled so bad that something had to be done. Timing was set at 14* and all tune up stuff was brand new. TPS voltage was good as well. So I decided to order a Mac 2 1/2" catted Hpipe. This cleaned up my smell alot but I then noticed massive amounts of heat being generated inside my car as well as underhood. I didn't know what to make of it so I left it until one night I saw my converters glowing. I knew I had a problem then. Not too long afterwards I brought my car to Larocca's to have my blower installed and I told them about the converters. They said it could be a number of things like MAF, injectors, CAI, improper A/F, ect. All of which will be eliminated when I go to the 42# injectors, Pro-M 80 MAF, eliminate the CAI, and have them tune it.
Needless to say all of that was done in February. I hardly drove the car at all but the time I did was enough to lift the heads (thus needing my head gasket replaced) and burn my clutch. After that was taken care of it brought me to about May and my glowing converters was still an issue.
At this time my EGR valve and O2 sensors were eliminated and I am tuned without needing a chip.
Please keep in mind that when I was naturally aspirated and after getting blown, the car drove fine. I decreased fuel pressure by 10# and also increased fuel pressure by 10# having no affect on my problem with the cats.

Back to Larocca's again to have them check it out. After about a month of it being there they said they have a gut feeling that my camshaft may not be installed correctly and they would like to swap it out with a "blower" grind. Before I decided to go with that expensive job I had Larocca hook the smog pump up to blow air downstream to the converters in hopes of fixing the problem. Let me tell you that only made it worse. Cats glowed faster and hotter by doing this.

Larocca's said they are about 90% sure the cam swap will fix my problem so I had them order one for me and have it installed by them. They replaced the cam along with timing chain and distributor. The cam that was already in there they said was installed "straight up" and after degreeing it saw it was in at a 105* as opposed to 108*. I called Comp Cams and asked if that would create my glowing coverter problem and they said "NO". If it were retarded too much maybe but not by being advanced and extra 3*. Needless to say, converters and now headers were glowing and I had lost 60 RWHP. They then proceeded to swap that cam with a known good cam that was smaller, which they had lying around the shop. Everything still glowing and horsepower was still down alot. They pulled my coverters off and put an offroad hpipe on an the headers were still glowing. They then did a "leak down" test and found one cylinder to be leaking a little through the intake valve and another to be leaking down from who knows where but not even nearly enough to explain the 60 RWHP loss. They tried another stock computer with no resolve. Then they install a stand alone computer. The EPEC. They got my horsepower back up to where it should be said somewhere between my stock wiring harness and EEC there is a problem and they don't know what it is. Larocca claimed they got a great tune and data logged everything and I should be all set with this EPEC ($1200). My headers were no longer glowing but now it was time to put the converters back on to see. Sure enough after putting the converters back on cats glowed again. They played with timing and bypassed my MSD and boost retard with no resolve. They through a set of stock converters on too see if it was a problem with my MAC converters, but they too got extremly hot so they assumed they were glowing as well. They also had dynoed the car with the offroad and with my MAC converters and the cats showed a 15 rwhp loss which they say was normal and not indicative of clogged converters.

So NOW they say that it is something with my motor and they don't know what it is. They lost confidence after the cam swap didn't fix my problem. I still have to pay for the cam and install anyway (approx $1000). They are leaning on it being something with my Roush 200 heads but are not positive. They are basically leaving it up to me to decide now if I want to swap my heads in hopes to fix the problem because they can't gauranty it will. THEY DON'T KNOW. WTF DO I DO???

I am already in the hole for 1G. Edelbrock heads will be approx $1100 plus installation and I don't even know if my problem will be fixed. SOMEBODY HELP ME PLEASE. THX

why not just gut the cats?? I've heard of that happening on Rx7s and 3000GTs but never a mustang. Main reason Rx7s have that problem is because the cats are too restrictive.

I need to run with converters to keep emissions down. It doesn't look like the converters are the root cause of the problem. A 15 rwhp loss between an offroad h-pipe and and converters shows them as not being too restrictive at all.

If i were you i would get your car back ASAP. If they can't fix it in three months and several thousand dollars, it's never going to happen. Personally, i'd take the car to a different shop with a dyno and wideband EGA. Either that, or take it somewhere that can give you a good exhaust gas rundown (an emissions shop, perhaps). Having the numbers for NOX, O2, etc should help you track down what's causing the problem. A dyno run or emissions test shouldn't cost you more than $75 or so. That's a LOT cheaper than throwing another $1K into it and knowing it's still not fixed.

Just remember, the hot cats are not the problem, they are the symptom. Fix the problem and the symptom will go away. My $0.02.

Well being that I am not using a stock cam the emissions levels are going to be higher regardless. So much for Larocca being one of the best.

Larocca's does use a dyno with wideband. They also were able get real time data log info with the EPEC hooked up.

now i normally wouldnt go out name calling... but laroccas has ******* up my car on more than one occcasion... let me tell you a story that really pissed me off...

i had a 1991, with TFS heads, GT40 intake, custom lunati cam, intake and heads had extensive porting... i ran a 12.5 with the car, it wasnt abeast but it was quick... now i got sick and tired of always tighting header bolts, this was a big problem... so first LaRoccas swaps them out for new shorties.. and runs new bolts... he says after one week retighten and it should be all good... hahahaha they leaked just as badas the first... Now im sure everyone has heard some leaking headers it doesnt sound pretty... so i go back again... and tell them im pissed... he says well its kinda notorius for shorties to do that a set of full length ones wont... so i set out an buy a set of Hooker full length headers, shorty H-pipe... they instal it... its all good... it sounds soooooo much better.. now it sounds liek a beast...i ask if any more tightning he says..NO... about 1 month later i start to hear a slight leakage... so first i go to chk my oil... and im like " whoops.. i pulled out the whole dipstick, housing and all!!!!" they never bolted it to the header!!! after closer inspection... i notice one bolt is missing btwn teh two last cylinders on teh drivers side... and teh header is cracked on the flange.... NOW IM FURIOUS!!!
I call up... i tell him what happened, he said well one of the bolts may have came loose and the dipstick fell off... i said "so the bolt came loose and retighted itself???" he was stumped... he said he could do nothing for me bout the cracked header.. and that was it...

as far as taht goes.... im doen with laroccas... bring it to Crazy horse... or Outrageous... or Ida hes right around the corner

also now that i coem to thinking bout ur main problem... wouldnt you suspect the car to be running overly lean when it gets red hot liek that...

IIRC.... since ur headers are glowing... ur EGT's must be through the roof.. so u could normally suspect it leaning out... but if its robbing horsepower it could be running overly rich and its actually burning up in the headers... now i have only heard this... never hands on... so dotn quote me on it... ill try to find the post that i remember seeing pertaining to this.

It is my understanding that a lean condition will cause combustion temperatures to rise thus leading to glowing headers. Unburned fuel or an problem of being too rich would cause the converters to go through what is known as "converter meltdown" due to the unburned fuel lighting off when it hits the hot converters causing temperatures to rise to high in the converters, causing them to melt (glow).
Remember I am not using my 02 sensors so I am always running in "open loop". Larocca's says this is a common way they tune blown motors and it shouldn't be a problem. They say there are plenty of set ups out there just like mine with no O2s and running converters.

dont you think that could be your problem... i really wish i can help... it always feels good to figure some **** out for urself... i remember bringing my car there one time because it was running weird... like hesatating... he said it needed an altenator... so i replace it t is stilll doin the same *****... i said could it be my MSD has gone bad... hes liek Nahhh... sure enough i wwnet home unplugged teh MSD and plugged the factory back in.. and that was it...

I dont think that not having the O2 sensors connected is my problem because they were connected before I went to Larocca I still had the problem. I do know that I didn't start having this problem until I swapped my stock motor for my built motor.

If your car's O2 Sensors are unplugged, then it will run RICH.

Now if your car is running RICH it will start dumping raw fuel into your exhaust.

If you do not have your Smog Pump connected, it's no longer blowing 1-2 pounds of air into your exhaust to help the catalytic converters work (And to cool them down).

Now added your custom camshaft. It's probably got a overlap so it's probably allowing raw fuel to go into the exhaust at idle anyways.

With all those complications, your catalytic converters are causing a backpressure and getting clogged. This causes extreme heat between the converters and your headers. In otherwords, your catalytic converters are melting on the inside. Do yourself a favor, PUT ON A OFF ROAD EXHAUST and your problem will probably go away.

thats one of the funnest things i ever heard, if laroccas has problems fixing a stang u think these jokes can do it. lmao.

slvr302

Hey i think u guys are being hard on larocca's its not as if they refused to try to fix ur car or do anything about it. What can u expect if your heads and cam were bought used they can't guarante the quality or operation on used products. when dealing with performance products diagnosing problems isn't as easy as just plugging the car into a computer and running codes, and say well replace this. sometimes there are no codes and u have to go with what u know from experience. they tried the cats, they tried the headers, different eec, tried the epec on the dyno, timing/fuel, cam. sometimes it takes just replacing to find the problem. Be patient laroccas are know as the best tuners on the east coast and they didn't get that title just by changing spark plugs.

I think thats the problem 2. why are u running with no o2's the car will run extremely rich, plus the deleted smog like stated above will cause the cats to overheat along with the deleted egr ur car will run richer and hotter.

Actually, the cats will be cooler without the smog pump hooked up. The smog pumps purpose is to introduce oxygen into the cats to help the burning process.

I'm curious about the data logging and how the A/F looked on the wide band? Were the headers glowing at idle or only after a hard blast? My TT Capri glowed the headers once when the power valve on the carb stuck and dumped fuel through the engine. The motor ran poorly too (duh).

Seems like Larocca's was a little quick to add performance parts instead of troubleshooting the base motor. A guy here had a similiar problem a year or so ago and it never went away, he ended up getting rid of the car.

The epec throws a huge curve into the equation and I'm surprised they were unable to tune the problems out with it.

Jamie

you MILLED those heads .040, THAT IS A LOT OF MILLING...

are you sure your compression is SAFE for boost?

That sounds like a slight possibility...

I wish you luck...

I wasn't getting email notification so I will now respond since my last post.

forced88lx: I had O2 sensors connected when the motor was only n/a and I still had the glowing issue. The smog pump does not cool the converters. It's purpose is to help aid in the full oxidization process. BTW, when I had Larocca introduce the smog pump to blow air to the converters, they glowed much hotter and much quicker. The exhaust fumes are unbearable and that is why I can't run with an offroad hpipe. Eyes and nose burn like crazy. Fumes are way too abundant. Larocca has tried two different cams that have better emissions qualities with no resolve.

bmo37: You are absolutely right. I WILL NEVER TAKE MY CAR TO CRAZY HORSE. I'D SELL IT FIRST. I've delt with them in the past and not to my liking as well as heard many bad things with regards to that dude Chris.
Like I mentioned above. I had both, a brand new EGR, and the O2s were connected wehn n/a and the problem was there.

Ranchero5.0: I forgot at what point the headers were glowing but that has since benn resloved. The converters are still my problem now.
You are saying exactly what Larocca has stated to me with regards to the EPEC. For you guys that may not know, the EPEC was set up to run in standalone mode therefore the stock EEC is not even in the car. They were able to datalog everything and get the a/f ratio any way they want at idle, part throttle, W.O.T., and anywhere in between (thus not needing any feedback from the O2s with regards to a/f). The EPEC bypassed any emissions related components. With that said and everything else checking out with timing, ect. according to Larocca, there has to be something mechanically wrong with my motor. No computer is going to be able to compensate for that. If it were any sensors or a tuning issue, they would have seen it while datalogging and the EPEC would have been able to tune it out.

yellow5.0cobra: Larocca thought the same thing when I told them my heads were milled .040". The guy that built my motor said it was because I had very big valve reliefs and Larocca did confirm when they did my headgasket. My compression is supposed to be around 9:1. Otherwise it would have been around 8.5:1. I would have left it that way had I known I was going to get a blower.

For everyone that says 02 sensors need to be connected.....just remember they were connected when n/a and I had the problem. Also the EPEC doesn't need feedback from the O2s to adjust a/f because it can be adjusted throughout the entire rpm range. I appreciate all the responses and more would be appreciated as well. THX

I didn't read through the entire post because i'm too lazy. But if you want your car fixed right, take it to Dwayne at Outrageous mustangs in Jackson (where i live). The man knows his stuff, he might seem like he has a bad attitude but that's just him. I personally know him, and i don't usually let anyone touch my car other than him. My brother currently does some of his Public relations work. And don't call him, he sucks on the phone, take a visit to talk to him, the only issues i see is the extra bucks you'll have to pay for him to fix laroccas work, and it's race season and he's has alot of things going on.

One more thing, if you do decide to go, DO NOT go in there bad mouthing crazy horse, it's a bad idea trust me. (Say what ever you want about laroccas.

I have spent so much time and money on this car...the last thing I need to do is take my car somewhere where the dude has a bad attitude. They are usually the guys that don't listen to **it you have to say and talk as if you don't know anything because they are the so called "professionals". Everyone always thinks that the shop they deal with is the best and should be able to handle this problem. If my car was somewhere else besides Laroccas and I was still with my problem, then someone would be saying they are the place I need to get my car.
One of the main reasons my car is still at Larocca's is because they have communicated very well with me even though this problem has really tried their patience and killed alot of man hours I will not be paying for. And believe me....I have called there so many times it is unbelievable. They never blew me off yet...not once. That's way more than I could say for any other shops I've delt with in the past with regards to anything. Don't get me wrong..I do appreciate your response.
Maybe since he is not good on the phone, you could print this post out and let him take a look at it since you are friends with him and all. I can't miss work to go all the way down to Jackson to have someone brush me off in a matter of minutes.
BTW, my experience with Crazy Horse was many years ago so I would have no reason to bad mouth them unless of course he mentioned them as being an option.