How to identify 2004 cobra 9 thread cylinder heads?

[89slowgt331]

I am going to look at a pair of 9 thread cylinder heads, the seller thinks they are from a 2004 cobra, are there casting# or build date's to verify what they are? they have valvetrain and cam's, what is the difference between the 2003-4 cobra and mach 1 besides cam profile? thank's for any help i just do not want to buy head's and find out they are older cobra or lincoln heads.

 

[Ironhand]

Umm count the threads in the spark plug holes....

I don't know why so many people make a big deal out of them. If you torque the spark plug down correctly 4 threads should be more then enough.

 

[Robertp]

I agree 4 threads I've been been running boost for years on 4 thread heads with no problem but I've always torqued them to 14 ftlbs, then I'll have customers come in with a blown out plug done at other shops and I'll check other plugs and their loose

Just what ive found

Robert

 

[TRBO VNM]

Yup, the trick is usually making sure they are tight. If loose at all, say bye bye to plug and COP. I saw this happen to a guy that used a well known shop and when he had the car towed to me, the damn COP cover wasn't even tightened down. Turned out all 4 plugs on that side were loose....well, 3 were. The 4th was blown out.

 

[Jomo1994z71]

I was amazed how easy my stockers after 36,000 came out...

 

[89slowgt331]

I understand 4 thread heads are fine, mine have been for 108k, I wanted to get a back up set and found a good deal, I just wanted to find a way to know if there is na way to identify our heads and valvetrain, I know the mach 1 and merc.muarader have different camshafts, what about cam followers and valve springs are they different?

 

[Jimmysidecarr]

I understand 4 thread heads are fine, mine have been for 108k, I wanted to get a back up set and found a good deal, I just wanted to find a way to know if there is na way to identify our heads and valvetrain, I know the mach 1 and merc.muarader have different camshafts, what about cam followers and valve springs are they different?

You know the Mach1 and Marauder have different cams?
How did you happen to come by that information? It is wrong.:nonono:

The heads are an assembly and everything on them including cams is identical on Mach 1, Marauder, Aviator.... and 03/04 Cobra.

The early ones had 4 threads the later ones had 9... on all of those vehicles.

Since the Aviator remained in production the longest it, was those revised heads that are used for the often talked about improved service part replacement heads.

If the heads you are looking at are from a 2004 Cobra you should be asking yourself WHY are these heads not still on the engine they were built on and are instead now up for sale? If they came off a HURT ENGINE check them out VERY carefully, if they are off an engine that isn't hurt, why are they being taken off and sold separately from the engine?(tick-tick-tick???)

To check for threads:
Pull one plug, roll up some clay in a small 3/16" roll and press it against the threads in the spark plug hole with a pen, pencil, screw driver or whatever.

Remove clay and count the threads.

Used heads could have replaced cams in them no matter what they cam off of.