Just did a compression test last night all cylinders 160+ would a stock 134,000 mile motor have this compression?? From what i understand the motor is stock...the heads still have stock head bolts i want to know if that compression is normal for a 24 yr old higher mileage motor has the motor been ran threw or atleast up top on valvetrain or could it be still OEM... i would think after 100+ thousand miles the rings/cylinder or springs would be a bit on the used side?? i wanted to take motor out and build it because didn't know what was in it but seems like i have pretty good compression, would the compression test show if a cam lobe is worn? just want to make sure the engine is tip top i read horrror story's of wiped cam lobe's.
Engine Compression #'s
- Thread starter 87chrisss
- Start date
Welcome!
By registering with us, you'll be able to discuss, share and private message with other members of our community.
Turbo-Archie
Active Member
- Joined
- Oct 8, 2002
- Messages
- 1,529
How many strokes to get those numbers??
..
..
im glad you asked !! it seems Mechanics have different opinions on this?... i honestly used the instructions on the compression tester gauge it said 3-5 compression strokes, But i have 3 buddies that own shops here in Miami they do good work.. and funny they all answered different?
One of them said by the 3rd compression stroke it should show the compression on that cylinder..
My other buddy said 5+ compression strokes OR keep going until the needle stops advancing..i tried this one last night and my psi went up to just below of 180psi??
The last buddy agreed 5+ strokes or until the needle stops advancing, the reason HE said why it's better to 5+ strokes or until the needle doesnt advance on the gauge is some engines could/might have a sticky valve or gunk/ carbon build up in the engine.. i took a video last night of me testing the compression at night with a light so if you would like to see this archie i can post it up ? i tested 3 stokes oppose to 5+ strokes and seem to get a slightly higher rdg on 5+ compression strokes. Any comments on what they said or on my test? ?
One of them said by the 3rd compression stroke it should show the compression on that cylinder..
My other buddy said 5+ compression strokes OR keep going until the needle stops advancing..i tried this one last night and my psi went up to just below of 180psi??
The last buddy agreed 5+ strokes or until the needle stops advancing, the reason HE said why it's better to 5+ strokes or until the needle doesnt advance on the gauge is some engines could/might have a sticky valve or gunk/ carbon build up in the engine.. i took a video last night of me testing the compression at night with a light so if you would like to see this archie i can post it up ? i tested 3 stokes oppose to 5+ strokes and seem to get a slightly higher rdg on 5+ compression strokes. Any comments on what they said or on my test? ?
Also to clarify.. i had no reason to do a compression test.. i was looking for a reason to take heads off and port them and go roller but my engine seems to be pretty healthy i dont go to the track very often now that im a dad so i'll just keep the money in the bank for now...i would have thought my motor might have been on the used side because it seems 100% stock and its around 128k miles but maybe a previous owner did a head job or might have an engine swap? or even a stock rebuilt or might be 100% stock...either way compression seems great on all cylinders...fyi these were dry test's no oil added to cylinders, and it engine was cold
Don't touch it!
You don't ever want to break the seal on those factory head gaskets and factory torqued head bolts if you can help it.
These motors will go low 11's on completely stock long blocks and live for a long time if you don't detonate it.
I would highly recommend putting a new timing set on it though. Don't ask me why I would recommend that......
I'd also recommend a valve spring change. Comp 980's are pretty much the norm for a good replacement spring that is a slight bit stiffer.
You don't ever want to break the seal on those factory head gaskets and factory torqued head bolts if you can help it.
These motors will go low 11's on completely stock long blocks and live for a long time if you don't detonate it.
I would highly recommend putting a new timing set on it though. Don't ask me why I would recommend that......
I'd also recommend a valve spring change. Comp 980's are pretty much the norm for a good replacement spring that is a slight bit stiffer.Turbo-Archie
Active Member
- Joined
- Oct 8, 2002
- Messages
- 1,529
Post up what you get with three strokes...
..
..
Should be no problems with your cam when changing the valve springs, I changed mine out and put in the LT1's and haven't had a problem. Most of the storys about wiping the cam are from people wiping out new cams on installation I bet, the majority of them. Your cam and lifters are well hardened in now, I wouldn't worry about wiping the cam.
Turbo-Archie
Active Member
- Joined
- Oct 8, 2002
- Messages
- 1,529
On the three strokes, were they all the same as Bison says above?
I only had 65psi but it would catch up the more I stroked it..
..
I only had 65psi but it would catch up the more I stroked it..
..
same psi all the way around..so, Bison/Archie what do you look for when looking to get status of engine health? ok..the first stroke goes up to about 90 2nd stroke about 120+ then 160 ..if i go up to 5 strokes she will near 180 on the gauge i'll post the vid give me a sec but regardless how can i check engine health everyone points to compression test?
COMPRESSION TEST TB.COM - YouTube
I SOUND WEIRD ON THE VIDEO W/E I KINDA PAUSED A HOT PACK OF LADY WERE JOGGING BEHIND ME AND I TOOK A GLANCE KINDA CAUGHT ME OFFGUARD DOING THE VID LAST NIGHT....ANYWAYS THIS IS THE VID WITH 5 COMPRESSION STROKES THE ONE WITH 3 STROKES IM DOWNLOADING NOW
I SOUND WEIRD ON THE VIDEO W/E I KINDA PAUSED A HOT PACK OF LADY WERE JOGGING BEHIND ME AND I TOOK A GLANCE KINDA CAUGHT ME OFFGUARD DOING THE VID LAST NIGHT....ANYWAYS THIS IS THE VID WITH 5 COMPRESSION STROKES THE ONE WITH 3 STROKES IM DOWNLOADING NOW
94z286speed
Member
- Joined
- May 17, 2004
- Messages
- 99
be careful doing compression strokes with a pack of hot joggers around!:biggrin:
I can tell just by cranking the engine if the cylinders are ok. I know the health of it based on the parts in the combo and the performance. The one I was running last summer had 110-120 on all cyls with no plugs in the other cyls. It made 700hp without trying too hard. You could have a lot if leakage and still not lose power.
Similar threads
