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BlueOvalPower
03-01-2008, 09:20 AM
Is there a site or can anyone explain the difference between say the 96-98 and 99-01 Cobras I have read a few references about them and I am in the market for another Cobra and want to know if ones better than the other etc. Not so much the hp/tq but the mechanical abilities strengths/weaknesses, thanks.

cobrabitn
03-02-2008, 11:02 AM
96-98 had heads with IMRC plates and the 99-01 had tumble port heads.
96-98 had coil packs and the 99-01 had coil over plugs

I don't really know if you would say one was definitely better than the others...

BlueOvalPower
03-02-2008, 01:08 PM
Thats good I was thinking along the lines like the early 03's some have the "tic" now the next question how can you tell first if they are a real Cobra like is there a Vin digit or something of that nature and 2nd how do you know if the long block hasnt been changed out with like a Mark VIII motor or similar? thanks for the reply.

ProfChaos
03-03-2008, 11:26 PM
Is there a site or can anyone explain the difference between say the 96-98 and 99-01 Cobras I have read a few references about them and I am in the market for another Cobra and want to know if ones better than the other etc. Not so much the hp/tq but the mechanical abilities strengths/weaknesses, thanks.


Generally speaking, the '96-'99 Cobras have a Teksid aluminum block and Teksid aluminum heads, manufactured by an Italian company who also manufacture blocks for Ferrari and for Formula 1 race cars. The '01 Cobras have the Windsor aluminum block, manufactured at the Windsor Aluminum Plant, presumably in Windsor, Ontario, Canada. The Teksid blocks are supposedly of better quality, with the change to the Windsor block being largely a cost-saving measure. The '03-present Cobras have a cast iron block and aluminum heads that are ported to accommodate the Eaton supercharger. :)

The following link offers pretty good coverage of the differences between various 4.6 Liter Ford engines, including both SOHC and DOHC:

How to Build Max-Performance 4.6 Liter Ford Engines (http://www.mre-books.com/sa82/sa82_1.html)

According to Sean Hyland, the weak link in earlier Cobra 4.6L engines ('96-'99, and '01) is that they do not have the Manley forged steel connecting rods that '03-present Cobra engines contain. Hyland recommends that one "limit use of stock [connecting] rods [on '96-'99, and '01 Cobra engines] to [use in] engines of 450 hp or less." Otherwise, a broken connecting rod might lead to a horked engine block, as shown in the second b/w photo on the page "Connecting Rods."

cheers, :cheers:
--Professor Chaos

ProfChaos
03-03-2008, 11:44 PM
Thats good I was thinking along the lines like the early 03's some have the "tic" now the next question how can you tell first if they are a real Cobra like is there a Vin digit or something of that nature and 2nd how do you know if the long block hasnt been changed out with like a Mark VIII motor or similar? thanks for the reply.


The following Web page offers a detailed explanation of Cobra VIN nomenclature:

SVT Cobra VIN (http://www.carmemories.com/cgi-bin/viewexperience.cgi?experience_id=424)

The Ford part number stamped into the '96-'98 Teksid block is F6LZ-
6010-AB; the Ford part number stamped into the '99 Teksid block is XR3Z-6010-CA.

cheers, :cheers:
--Professor Chaos

BlueOvalPower
03-04-2008, 09:27 AM
Hey thanks that is what I was looking to know. I read about the Teksid block and I wasnt sure if that was a bad or a good thing. Thanks for the reply

Big Daddy
03-04-2008, 09:40 AM
Hey thanks that is what I was looking to know. I read about the Teksid block and I wasnt sure if that was a bad or a good thing. Thanks for the reply

Good thing! I replaced my '01 block with a '98 block when I hydro locked the engine and blew a huge hole in the block. Have had no problems with the block at all!

blueblazes
03-17-2008, 06:21 PM
the 96-98 cobras used whats called "b" heads, the 99-01 used "c" heads, and the 03-04 cobras use a variation of the c-head. All the intakes are interchangeable between the 99-01, 03-04, and the fr500's. Out of the box the fr500's have the highest flow but ported 03-04 cobras have highest flow of any 4v head with the exception of the gt40/gt500 heads which are a variation of the 2000 cobra r head.

These have a totally different design than the other heads requiring the use of special intakes when putting them on a cobra motor.

The other style of heads are the aviators which are a "c" head derivative as well as the navigator heads. These are close in port design to a "c" head but require either machining of an intake to fit or a specialized intake.

There were also differences in cams between the years thats a long story but know that there are lots of differences between the years. Even between the mach1's and 03/04 cobras which share the same heads.

As for blocks the 96-98 blocks are coveted among the cobra community they have the highest horsepower capability with some guys in the professional drag racing scene using these blocks up into the 1500+hp range. :eek::eek:
There were some leftover blocks that made it into the 99 model year and some have rumored that a few even made it into the 2001 model year. For most part these were phased out in 99 and moved over to the windsor style block. These are similar to the explorer blocks and were for the most part turds.

In 03/04 ford released the iron block for the terminators after the obvious failure of their attempts at making an aluminum block for the cobras. These blocks have been used in applications pushing 1000 hp and more. The downside to these is the weight where as a conversion to a teksid block is a weight savings of roughly 70lbs in an otherwise heavy pig.

Teksid blocks can be found in the mark8 lincolns from 94 up i believe as well as the 96-98 cobras! If you can get your hands on one then snatch it up as they are great pieces for a rebuild if you ever have a motor go poof