2007 Roush mustang with gouge in cylinder 7

[LkW222]

I have 2007 Roush Stage 2 mustang i have owned for 18 years. It is a beautiful red convertible with only 32000 miles on it now.. 14 years ago we had a roush certified mechanic add the roush chrome m90 supercharger and also had JDM engineering do some more engine upgrades and dyno tune it. For the last few years when it was cold it would run rough. I let it warm up in the driveway for 5 -10 minutes and it runs great. Lots of power. I took it to a garage a couple times. They put new coils in and a new maf sensor but that didn't help. I took it back again recently to see if new feul injectors would help and then got the devastating phone call saying that cylinder 7 compression is low. The borescoped the cylinder and found a fairly large gouge. They dont do work that extensive. I dont know what to do now. I have called around and being told it us going to cost me as much as 15k to fix. The car is nice - wins at car shows often. But 15k seems crazy. What should I do? I am sick over this. I live near Corning NY.

 

[Midlife Crises]

You didn’t say if it is burning oil or smoking. Just that it runs rough until it warms up. Cylinder 7 compression is “low”. How low? Compared to the rest of the jugs.
You might want a second opinion from a different shop before looking for an engine.

 

[whitmanink]

just as midlife said ,
id have a friend and you do a compression test and leak down yourself , or have the shop do it and record the numbers,
%10 difference is ideal,
but up to %30 is allowed ..

i doubt the numbers are that out of whack that it needs a new motor ,
if that one is low (between %35-40 difference in just thats one cylinder,,

well id just run it like it is ,, if she pulls hard when warm and no issues ,, then id just drive it until i felt like dropping all that cash for a block , and have the down time

 

[StockishS197]

Same comments as above. If it comes around as it warms up, I don’t think the walls could be that scored and may be just lazy rings, especially being low mileage.

I would also get a second opinion, and give it a few good Italian tuneups. Have had good luck with Valvoline Restore and Protect too to unstick rings.