03 cobra compression as low as Oprah’s Testosterone

roy_1031

roy_1031

roy1031
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Maybe you should invest in a wide band. They’re relatively inexpensive and a great tool to have. Installation is pretty straightforward as well aside from have a bung welded into your mid pipe.


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PNWSVT

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roy_1031 said:
Maybe you should invest in a wide band. They’re relatively inexpensive and a great tool to have. Installation is pretty straightforward as well aside from have a bung welded into your mid pipe.


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Click to expand...
2 things.....
1. how do i get my signature to show up like yours lol
2. I have a wideband and under WOT its low 11's and at idle it bounces between 15.6 and 13.9
 
roy_1031

roy_1031

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PNWSVT said:
2 things.....
1. how do i get my signature to show up like yours lol
2. I have a wideband and under WOT its low 11's and at idle it bounces between 15.6 and 13.9
Click to expand...

Ummmm not sure about the signature, I edited through the website itself not on Tapatalk or the app.

Low 11’s isn’t bad. I believe mine was at 11.2 at WOT in 4th gear. Idle cruising and letting off rolling in gear etc, my afr was all over the place as well. Is this car your daily driver or a weekend bruiser?


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PNWSVT

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Okay here we go...

I pulled the plugs and coils, none of the coils were snapped back over the plugs like they should.

I did the compression test, here’s my numbers

1. 140
2. 130
3. 135
4. 136
5. 125
6. 80
7. 110
8. 120

Then I did a leakdown on number 6 and 7. Here are those results

6. 84psi and 90% leak. Air heard and felt flowing out exhaust and the breather tube going back into the intake. No air or bubbles in dipstick or radiator.

7. 89psi and 45% leak. Air heard and felt flowing out exhaust and breather tube going back into the intake. No air or bubbles in dipstick or radiator.

I also bore scoped my cylinders and they looked even as well as my plugs all looked good.


What’s the verdict ???
 
StrayBullitt

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Sorry about your exp. at TMS I warned you ;)

jk, sounds like they were mostly correct but maybe didn't take your repair as seriously as they should have... that said I'm not too sure I would fully trust them doing those repairs anyway.

I know Matt is typically scheduled out on the dyno @ Turbo Technology, but they might be able to get you in for a diagnosis and other repairs sooner though. I would trust them for that level of repair.. There is also Brad's Custom Auto up north you could consider for the full repair.

Might want to think about if you are willing to take on some of the work yourself, if you are willing to pull the heads, I have heard DG Machine shop in Auburn is solid. Good Luck!
 
PNWSVT

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StrayBullitt said:
Sorry about your exp. at TMS I warned you ;)

jk, sounds like they were mostly correct but maybe didn't take your repair as seriously as they should have... that said I'm not too sure I would fully trust them doing those repairs anyway.

I know Matt is typically scheduled out on the dyno @ Turbo Technology, but they might be able to get you in for a diagnosis and other repairs sooner though. I would trust them for that level of repair.. There is also Brad's Custom Auto up north you could consider for the full repair.

Might want to think about if you are willing to take on some of the work yourself, if you are willing to pull the heads, I have heard DG Machine shop in Auburn is solid. Good Luck!
Click to expand...

Oh trust me I’m not taking this car back there at all. I’m going to call turbo tech in a few min and let them know what’s going on and maybe like you said they can get me in sooner, especially since they went from getting money for just a tune to a rebuild.

Is there any particular type of oil to put in the cyl? Or just any oil.

D&G Has made some great motors up here as well as cope brothers. Have you heard much about blood enterprise ?
 
PNWSVT

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Lol I just called Blood Entereprises and they are booked till the end of winter! But this guy on the phone knew what’s up, offered a little more advice as well.

So I’m going to pull the valve covers, and repeat the test. I’ll be re doing the compression test with the oil as well as the leakdown but with the valve covers off so I can make sure the valves are seated 100% in the compression stroke at TDC. Then I’ll really know if I’m up shit creek without a paddle.

If the air is blowing by as much as it sounds, then I’m getting new valves as well, because the previous owner only did seals and springs but left the stock valves ! So it would be no surprise if it didn’t have an issue there. But if it’s my rings I’m pretty screwed. These motors don’t like going .30 over from what I read and I’m already at .20 and if that’s all true I’m getting an MMR long block (5.0 900hp)
 
PNWSVT

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Okay I did a wet and dry test right after driving the car (as long as it took to get my plugs and intake off etc) looks like my rings are bad in number 6 and 7. With the wet test my compression went up 30-40 for those two cyl.

Going to pull the engine and take it to the machine shop ASAP. At what point is it more worth it to purchase a long block vs a rebuild ?
 
Z

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you might be able to rering it, which is not going to be real expensive.

if you have to rebuild it you should be able to reuse your crank & rods, so the only parts you'll need are pistons, gaskets, bearings etc. that will also be less expensive than a short block.

if you want more displacement, just buy a stroker short block.

IMO
 
Shadow Grey 03

Shadow Grey 03

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The only way to know for sure what needs done is to pull it apart. Definitely needs rings. Outside of that is just speculation at this point.
 
T

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PNWSVT said:
I took my car in to “The Mustang Shop” in Auburn this afternoon to find out what the hell is going on with this overwhelming smell of gas, the rattle from my TOB or elsewhere. Turns out I have what he called “E85” fuel lines, no fuel leaks anywhere, and fuel smell only in the rear of the car still with the smell then making its way to the inside of the car. Either way the problem is still there. He told me how I basically needed a new transmission because of the TOB sleeve being crap and how it would be as expensive to change my sleeve. So he didn’t even look at the trans.
My car keeps hesitating and bucking at low rpm when I come out of a shift or if I let off the gas then slowly get back on it, so i thought maybe my fuel filter is clogged causing issues? So I had them pull the plugs and tell me what’s up. All the plugs looked good except one that was slightly and I mean SLIGHTLY darker, they asked if I wanted a compression test so I said sure why not. Here’s what I got:

4: 120 8: 120
3: 125 7: 110
2: 130 6: 90
1: 120 5: 120

Now I’m no expert but a 30 pt swing seems wrong. My numbers were all pretty close minus number 6. They all seem low compared to what I see so many people running on here. They told me this low of compression would make sense if the engine was set up around 8:1cr which he said was really low even if I have a 3.4L whipple.

Next step is obviously a leakdown test, which I’m not looking forward to.

Any advice ? I plan on doing my on compression test and leakdown test, after that I have no ****ing clue what sort of grenade I’m sitting on


Thoughts ?
Click to expand...
If things haven't changed because of the supercharger, your readings should be within 20% cylinder to cylinder. I am doing the TOB sleeve replacement mod. It has been a total PITA, especially for something so basic. As a matter of fact, I just posted a question for experts on T-56.

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Livernois Motorsports

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If you are in search for a replacement engine we can always help out and build you a custom one for you! Shoot us a pm or a call at 313-561-5500 extension 104 or ask for cody and ill be glad to assist you!
 

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