Originally Posted by JVRMach (Post 1070677)

Ok, I have a 2003 which I though was built in July of 2003 but I have the 8-9 turn heads on my car. This I know because I just changed my plugs. Any thoughts on this?

Originally Posted by MachPowered96 (Post 1075267)

So....

That was a lot of info..lol

Dan, what would be the reason for the ticking noise staying around with the same set of heads on 3 different engines? I helped a buddy swap an Aviator engine in his 1999 GT. He ran Crower 3's and made great power N/A. He then built it with 03/04 Cobra rods, Probe SRS Pistons, and cast crank....engine (cylinder head) still ticked.

He then tore the engine apart, rebuilt it, and had some work done to the heads, still retaining the stock guides....but installed +1 valves and had some minor port/chamber work done. The head still ticks to this day.

Every mod motor has piston slap? You are basically stating that every shortblock has this problem. I personally have had about 10 different mod motor set-ups and I have never heard one bit of "irregular" noise come from the engine. Several of thoe 10 engines were 4V's. And my current car is a 4V.

Thoughts/opinions?

Originally Posted by Ben99GT (Post 1077644)

Probably because the tick was in the head like Ford says. How many 4Vs with bronze guides and good valve jobs tick?

Originally Posted by BluBlurr32V (Post 953762)

http://i133.photobucket.com/albums/q...1/fa5fc9c9.jpg

I borrowed this image from EPIKMACH, sorry I just needed a quick pic. Credit for the pic goes to him!

Originally Posted by DanB (Post 954529)

Look not trying to sound like an Richard but here are the facts!!!!!!



This is wrong!!!! Just to state the obvious here when you removed your heads and had bronze guides installed the machine shop also did a valve job to insure that the valve sealed after the new guides, when they tore in to the heads the also milled the bottom ( also known as the deck surface) in order to make it smooth enough for a MLS gasket to reseal when you mill a head you are making more cylinder pressured because the combustion part of the head is closer to the piston thus means less square area in turn adds more pressure to the piston thus stabilizing the piston to one side or the other (it Dampens to noise). The noise is actually still there it is just that you cant hear it due to added pressure. On a cobra it gets real bad because of the cylinder pressure they have due to the supercharger that is why it is more prone when idle and not under high boost. there is already enormous pressure on top of the piston so the clearance on a forced induction would have to be enormous for you to hear when the car is pullied and under pressure. That is why you hear it loudly when at idle due to less pressure

Originally Posted by Boss 330 (Post 1213157)

This thread makes my head hurt. The tick was/is caused by excessive stem to guide clearance, end of story. The guides had too much clearence right from the start. This allowed the valves to hammer back and forth in the same plane as the followers. The guides would wear into a oval shape. This movement scrubs the valve on the seat and the valves soon lose the ability to seal. Low compression is the result.

Most all of the new replacement heads sold over the counter had the same problem. Ford specification was .002 max stem to guide cl. the brand new heads were .004-.005+
Also..Piston slap gets worse as the pressure goes up. When the thrust transfers from one side of the skirt to the opposite side of tdc that is where the rattle comes from. This gets really ugly with the big piston to wall clearence some builders seem to like. We tore down a 4V this week and had a suprise.
The owner stated the oil fumes were making him sick. This thing had a few thousand miles on the rebuild. The engine had .020 over pistons in a .030 over bore.

Some pistons have pin bores offset to help reduce the slap on cold starts. Many new engine designs have the cylinder bores offset in relation to the crank centerline.

Originally Posted by Boss 330 (Post 1213157)

The owner stated the oil fumes were making him sick. This thing had a few thousand miles on the rebuild. The engine had .020 over pistons in a .030 over bore.

Originally Posted by DanB (Post 946968)

Here is the difference



02-03 mach 1 and cobra heads
this was the first run of the mach1 and cobra heads, after a million complaints about excessive noise in the valve train on the drivers side ford figured they had to do something so they revised the drivers head. When the car came on to the service drive the first thing the service writer does is run TSBs to find any open complaints and the drivers head had a TSB for noise so ford started replacing them well about 2-3 months in to this they found out that they were redoing some of the cars that had already been don’t so the change the head by having then painted with a blue strip. Now this has no reworking other than some different valve guides but in fords attempt to keep the technicians from double dipping they painted the service head blue so the service writer knows if the TSB had been done or not. This head was the first head and only has 4 spark plug threads


mid 03 to end of 03 cobra and mach 1 heads

This is the 4V head that has been painted with a blue strip to show this is what ford though would take care of the excessive noise from the valve train (little did ford know that the piston slap was the cause for this noise) way to go ford !!!
This head also possesses 4 sparkplug threads




11/15/2003- 4/2004
This was the first 9 thread head
this was the 2004 cobra and the mach 1 head for 2004 this head was completely different. This was the last revision head also known as the FR500 replacement head. This head was issued some time after 11/15/2004 I have confirmed this with every 2004 cobra and mach 1 I have ever touched (approximately 50-60 cobras and 20-30 mach1s ) this head has improved ports also the coolant passages have also been changed. The only way to tell what head you have is by the thread count in the head. 9 thread signifies you have the 2004 heads and 4 thread signifies you have the 2003 heads (while nonpainted 2003 heads notes early 2003 heads) Now there is an easy test to see what heads you have seeing as how all of the threads are at the bottom coming up you can perform a simple thread count test. Start from the tight position and count the number of turns it takes to remove the sparkplug 4-5 turns means you have 4 thread and 8-9 turns means you have the 9 thread heads. if you are buying heads keep this in mind or simply contact me to buy new heads 9 thread with the improved passages 1500 a set complete new

Originally Posted by highfigh (Post 1216025)

Interesting discussion. I have a question.

I just bought an 03. The sticker on the door says 6/03. So what heads should I have? The 4 thread ones, right?

But I count 8.5 turns when removing the spark plugs. So by your statement these are the newer heads? I have no blue stripe on my heads, just a yellow X, i think.

I'm not understanding the logic of your simple test. A spark plug for our cars has like 9 threads on it. How would it matter how many threads are in the heads? It still takes 9 full turns to fully seat a spark plug, whether there is 4 threads in the head, or 9 or 5 or 1....

Am i making sense or am i totally missing something?

Originally Posted by lxh89 (Post 1216041)

It doesnt matter if the head has 1 thread or 400 threads, the number of turns to remove the plug is determined by the spark plug thread count :)

Tony

Originally Posted by highfigh (Post 1216049)

Tony, I think we may be the only 2 here that understand that. At least I didn't see anyone else bring this up. So why is this a sticky anyways? I don't see how this is anything but confusing.

I have 92k on my engine, no ticking or odd noises whatsever. No blue stripe.