'03 Compression Test Results

[88foxbod]

8 - 180 4 - 175
7 - 190 3 - 185
6 - 190 2 - 159
5 - 190 1 - 155

34,000 miles
The motor was made in made back in August 2002 and hasn't developed the common *tick* in motors built before November 2002.
The previous owner failed to have the head replaced before the warranty expired so I went ahead and did a compression test to see how its looking.
And obviously the Drivers side head is doing worse off. None of which immediately concern me but the number 1 and 2 cylinders I may need to keep an eye on.

Any thoughts or concerns? I only did a dry test because I didn't have any extra oil laying around for once. Anyone recommend I do a leak down test?

 

[jumperjack]

Why would you think the head is the problem?

 

[NateTermi]

190 seems high for a low compression motor. I know my compression test was all at about 165 psi.

 

[Robertp]

Just for your info cylinders 1-4 are on passenger side not driver

 

[My96z]

Was it done cold or hot? I would definatley test it with oil.

 

[NateTermi]

I thought it was
Driver-passenger
1. 2
3. 4
5. 6
7. 8

 

[SVTDice]

190 seems high for a low compression motor. I know my compression test was all at about 165 psi.

Yeah mine is around 165 +/- 10 or so. I've seen alot of people on these forums with Compression of 180+ So...Whats the deal? My Engine is sound as a pound as far as I know.

 

[AlwaysBoosted]

I thought it was
Driver-passenger
1. 2
3. 4
5. 6
7. 8

I believe it is

4 8
3 7
2 6
1 5

 

[NateTermi]

Yeah mine is around 165 +/- 10 or so. I've seen alot of people on these forums with Compression of 180+ So...Whats the deal? My Engine is sound as a pound as far as I know.

Hmm.. Weird. Maybe they got theirs up to nearly 200* before they did it. 180+ seems high to me for a low compression motor but idk...

I believe it is

4 8
3 7
2 6
1 5

So it's not the same as GM?

 

[Blueline]

The cylinders are as follows:

Radiator

5 1
6 2
7 3
8 4


compression numbers can be effected by the gauge, what's important is the difference in the numbers. For example one gauge may read 180 and a different gauge on the same cylinder and car may read 150.

 

[TRBO VNM]

I believe it is

FIREWALL
4 8
3 7
2 6
1 5
RADIATOR

The cylinders are as follows:

Radiator

5 1
6 2
7 3
8 4

These are correct. Same as GM? Come on man oke:

Bold is just what I added for reference.

I have seen these motors range from everything in the 150's to low 160's to the same in the 160-170's and on up into the low 190's.

 

[NateTermi]

These are correct. Same as GM? Come on man oke:

Bold is just what I added for reference.

I have seen these motors range from everything in the 150's to low 160's to the same in the 160-170's and on up into the low 190's.

Alright, thanks for clearing that up. This cobra is my first ford.:rockon:

 

[Brutal Metal]

Uusually you see lower numbers on #7 and #8, back drivers side!

 

[88foxbod]

Why would you think the head is the problem?

Im not really troubleshooting a problem, it was more like preventative maintenance to see what kind of condition the motor is in.
I was just refering to the known issue with the cobra motors built before Nov. 2002 that the driver side head does not have a direct path of coolant through the head to efficiently cool it down, which leads to damaged valves/rings and the notorious *tick*

Was it done cold or hot? I would definatley test it with oil.

It was done cold, should I do this on a warm engine? Ill grab some oil tomorrow and redo the test, and hopefully post the correct cylinder order!

4 8
3 7
2 6
1 5

 

[My96z]

More just out of curisosity. I would do it warm and then with oil to see if the results change.

 

[byron m]

Mine were 163-165 lb's on cold engine with 30.000 miles+or-a few.Built Nov.12/02.Seems normal for 8.5-1 compression.I belive it's important how fast it gives peak #,3or4 compression hit's you should be at peak #.Oil added to plug hole is usually added to a low cylinder and if it raises # the rings aren't sealed,if it doesn't it's a valve not sealed.Rule of thumb on stock motor is they all should be with in 10% of each other.The closer together the better for sure.

 

[hotcobra03]

Yeah mine is around 165 +/- 10 or so. I've seen alot of people on these forums with Compression of 180+ So...Whats the deal? My Engine is sound as a pound as far as I know.

mine was just check ..cyl 1-5 read 180..6-8 read 195...i did this test engine hot,,no oil added...was done on 3 different days

engine is stock with 310k....:rockon:

 

[ImaginationLand]

mine was just check ..cyl 1-5 read 180..6-8 read 195...i did this test engine hot,,no oil added...was done on 3 different days

engine is stock with 310k....:rockon:

......

 

[my92gt]

Dumb question, where can I get a compression tester??

 

[TRBO VNM]

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