Cracked headers, cylinder wash, how?

I'm hopeful with the lack of a muffler (and soon to be Hyper Flow CATS), that I'm pushing enough heat out and can maintain stock headers.....

 

Brian could you elaborate on the Ferrari headers. There were supposed to be some improvements on them but there was never any answer given on how they were improved or what material was used. Thanks.

 

Looks like they only offer aftermarket headers with no insultaion or repair (I guess, for the latter, outsourced to JP Exhausts)

 

I have a cracked LH manifold at 16,750 miles on my 1997 F 355. I am worried now that there might be damage to the motor since I prob put 50-100 miles on this header. Can anyone advise me to whether or not it is likely there is any damage?

Symptoms:
Insulation dust on the LH side of the engine bay.
SLIGHTLY louder on the left side.
I DO NOT hear anything different at idle, such as ticking or loud exhaust. It sounds basically the same as it always did.
I had throttle hesitatation/ flutter at 4500 rpms or so the last two times I drove.

I have not driven the car since I got it home after noticing the dust at a friends house, 5 miles away.

Can anyone help me get some peace of mind over this?
I did a compression test 500 miles ago and things looked good.

Thank you!

 

Take a deep breath. Your car isn't toast. Really

You need new headers. Most every 355 will.

Do what you need to do and get new headers. Do your own homework and figure out what you are comfortable with. There a dozens of threads on here on the subject and about a dozen vendors to choose from.

I just went throug new headers , new cats , new sensors and I just drove my car about 700 miles over two weekends and all is well.

Let me know if I can help. We are close.

 

thanks for the reassuring words. Did you put a lot of miles on your car after you realized your headers were cracked?I chose Nuvolari headers and they are being fabricated in England as we speak should be on the car within a week or so. Can't wait to meet up and take a drive around with another 355!

this may be a difficult question to answer but how long does it take for damage to be done to a motor when the car is driven with cracked manifolds? Seems some people suffer massive problems when this is done while others don't. I guess that just leaves me confused and a bit uncertain about the future of my motor

 

I don't know the answer to that and no one can give you the correct answer for your situation and specifics. The theory or mode of destruction is that the insulation gets reverted back into the cylinders and wreaks havoc.

I'm sure that if that is the case that the damage and amount of it are not absolute and certainly not uniform across the line.

Put your new headers on and have a compression test done. Hopefully you will be reassured and move on

 

I agree with much of what you say... but seriously, who the F cares if it is California legal. I don't live in California, don't plan to live in California, and likely wouldn't sell anything of value to anyone in California because of the politics there.

As far as insulating a header, that's trivial stuff.

If you want a decent header, you get yourself one fabricated by someone who has a clue of how to build real race headers, has access to a dyno, is willing to use 321 stainless or inconel, and is willing to put some development time into the project. Most people are not willing to do that, and generally speaking, even the fabspeed header is adequate provided you ditch those horrible catalytic converters which I am sure are 99.9% responsible for the problem in the first place. It would appear that they simply cannot flow enough gas to keep the EGT's under control, which results in header failure (usually on #2) and then results in the motor eating that cylinder in short order due to excessive EGT. The whole exhaust is a nightmare due to government regulations coupled with design restrictions imposed by Ferrari (Ferrari has culpability in this too).

If there was no catalytic converter, I am willing to bet that there would be few, if any exhaust failures. The whole Slow Down light non-sense is a clear indication that they knew the catalytic converters were the culprit.

Mark

 

I remember looking at an F355 once at a used dealership and the salesman told me it's running fine now but it's going to fail with something internal within 24 months. Then I would be in it with a repair bill for thousand's. Also mentioned doing the routine maintenance with fluids would put me back at least a thousand per year regardless if I drove the car 1 mile or 5K miles per annum.

That's when he steered me towards the used 996 GT3 on the lot telling me that the Porsche's in comparison are bullet proof. And that was the first and only time I had a salesman guide me away from a car that cost more, on the lot, to another that was about $5K cheaper. One of the rarest thing's in car sales is an honest salesman. One would think that they would want to flip the F355 just to get it off the lot. It only had 6K miles on it - and I thought it was a great value. Later I went home and read up on the car and all the potential issues.

I still love how it sounds and looks but just moved along.

 

I have more experience in the porsche 930 world, but for what its worth, I am not sure that running somewhat rich would damage the piston (quickly at least)...

With most cars, you shoot for an Air/Fuel ratio of 14.7 or so... Lower is richer, higher is leaner...

Due to concerns about grenading turbo motors, many/most folks run their 930 on boost at an AFR of 10-11... Thats RICH. These cars idle best at an AFR or 13 to 13.5... some what rich.

If my 930 is trying to run low RPM's at an AFR of 10-11 its pretty obvious, and it runs like crap. Exhaust smell would push you 20 feet away from the car. AFR's below that, the exhaust is smoking.

The point being, if a header (or other leak) caused your engine 02 sensor to run the motor rich, you would most likely know about it (whether through the CEL or other means). If it were slightly rich, it may not be noticeable, but then again it wouldnt be likely to damage your motor either. Extremely rich, is awefully noticeable...

Many/most 1970's muscle car owners seem to run their motors stupid rich. You can smell it two cars back going down the road. A porsche with a correctly set AFR, and no cats, doesn't give off the same "smell."

Bo

 

It would be nice if the slow down lights were in fact accurate. On a testarossa at least, often they just go on for no reason. I thought these were triggered by a heat thermocouple? If thats the case, they should never go off on a car without cats. And they should never go on when the car has just been started... Yet, they do...

Electrical gremlins...

 

The reality is that most 355s are relatively troublefree cars.

Obviously, the Porsche must have been his buddy's car.

 

FWIW and many months late .... I just saw this thread ..... and if it hasn't already been answered, the cat particulate reversion back into the cylinder/intake would happen during shifting .... right after acceleration and right into a shift ... the throttle butterflies close abrubtly and create a huge vacuum in the intake tract ..... then during overlap, that vacuum is transmitted through both exhaust and intake valves and pulls on the exhaust gases and whatever else is in the exhaust, then into the combustion chamber and even up to the intake tract.

 

This makes sense all the more reason for an F1. Shifting at over 7000 gives less time for the reversion. Ha ha

As for the post about all the problems the 355 has well i. Must have got a good one because none of those seem to have caught up to me yet.