What is stock compession on 1991 5.0
#1
What is stock compession on 1991 5.0
Hey everyone well I was wondering what the stock psi compression was on a 1991 5.0 mustang, so in a short while when i run a compression test ill know whats good and whats not. Also just saying i dont need to know it's 8:5:1 or whatever i mean like should it be around 170psi, or what?
Ok then i would like to know what range is still considered good and isnt bad enough to cause poor performance compared to stock, thanks sooo much guys.
Also im wondering because the 1991 mustang i bought seems to have no ***** compared to the last one i had, and it is bad comp or it needs a tune up bad because my 84 c20 with a stock 454 is faster then it and its a 16-17 sec 1/4 mile truck lol.
Ok then i would like to know what range is still considered good and isnt bad enough to cause poor performance compared to stock, thanks sooo much guys.
Also im wondering because the 1991 mustang i bought seems to have no ***** compared to the last one i had, and it is bad comp or it needs a tune up bad because my 84 c20 with a stock 454 is faster then it and its a 16-17 sec 1/4 mile truck lol.
#3
WELL there was one cylinder that wouldnt go above 10psi, so im guessing the motor is junk since i cant tear into it to replace the picton or rings.
Anyways my freind says it might have a hole in the piston, but i know ill be stoping by the last owners house and getting some money back for it.
Anyways my freind says it might have a hole in the piston, but i know ill be stoping by the last owners house and getting some money back for it.
#4
WELL there was one cylinder that wouldnt go above 10psi, so im guessing the motor is junk since i cant tear into it to replace the picton or rings.
Anyways my freind says it might have a hole in the piston, but i know ill be stoping by the last owners house and getting some money back for it.
Anyways my freind says it might have a hole in the piston, but i know ill be stoping by the last owners house and getting some money back for it.
So all i need to know rite now is because the last owner let it sit for 2years and says that it probably dumped fuel into cylinder because spark plug wires are old that the oil should work and restore compression, so can someone tell me exactly how i should do this and how long untill re checking compression agin?
#6
Well i tried the trick with filling the cylinder up with 15-40 heavy duty desiel motor oil and let it run for 2 minutes then got the same 10psi, then tried agin and same 10psi compression so i dont think it's the valves being stuck or bad gasket because it would have more then 10psi and it would most likely just leak out pressure.
#9
Wait but if it was a bad head gasket then chances are that it would have more then one cylinder lose compression, and they should have more then 10psi on them sill lol they would have kinda average compression then just leak out pretty fast if its bad. But i dont think the cylinder with 10psi lost and compression or at least know from when i looked so does that say anything.
#10
Wait but if it was a bad head gasket then chances are that it would have more then one cylinder lose compression, and they should have more then 10psi on them sill lol they would have kinda average compression then just leak out pretty fast if its bad. But i dont think the cylinder with 10psi lost and compression or at least know from when i looked so does that say anything.
Just pull the heads and get a visual , one of the valves could have a burn spot on it. Seen it in my old f150 started running like poop with no power, pulled the heads and one of the valves had a pencil lead sized hole on the edge where it meets the head.
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