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Compression test results..you tell me

  • Thread starter Thread starter xexitenglishx
  • Start date Start date Oct 22, 2005
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xexitenglishx

Member
Jun 27, 2004
153
0
16
Oct 22, 2005
#1
  • Oct 22, 2005
  • #1
I did a compression test today and these are my rough results.
1 - 145
2 - 140
3 - 145
4 - 145
5 - 155
6 - 155
7 - 155
8 - 160

I did a cylinder balance test and it came out code 99 which means all is good.
I havent bought a leakdown tester yet. When i tested the drivers side compression the psi on the gauge held close to the number that it was jumping to..when the passanger side was tested the needle sweeped the whole gauge every time. I looked like it didnt hold the compression aswell. I dont know if it was just me or if that is something to be concerned with. The reason i am doing these tests is because im planning on turboing my car and i wanted to know it these results are good enough? Any advice would be great

Thank you
 

Dean85GT

New Member
Nov 27, 2004
502
1
0
Thorold, Ontario, Canada
Oct 22, 2005
#2
  • Oct 22, 2005
  • #2
compression looks good...all numbers are within 15% Happy modding.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Oct 23, 2005
#3
  • Oct 23, 2005
  • #3
One can have decent compression test results but bad leakdown results (important for forced induction). The numbers look fine here but I like your idea to do the leakdown first.

Good luck - sounds like a cool project.
 
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xexitenglishx

Member
Jun 27, 2004
153
0
16
Oct 23, 2005
#4
  • Oct 23, 2005
  • #4
thanks i gotta look into that. How long does it toke to do one of them? it seems teadious to have to bring each cylinder to tdc. How much would a shop charge for it? Thanks
 

Foxfan88

My Grandpa has great wood.
Sep 13, 2004
2,487
4
0
Miami, Ok
Oct 23, 2005
#5
  • Oct 23, 2005
  • #5
whats a leakdown test??
 
X

xexitenglishx

Member
Jun 27, 2004
153
0
16
Oct 23, 2005
#6
  • Oct 23, 2005
  • #6
You ened a special device adn a compressor. You use it to test the amount of pressure that is leaking pass the cylinder walls. Thus if alot of pressure liek a supercharger or turbo is added there will be either consuption of oil or other problems when you dont have a tight piston seal. Or well atleast tahts what i get out of my research.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Oct 23, 2005
#7
  • Oct 23, 2005
  • #7
Yep. The leakdown test helps isolate where compression is being lost. IIRC Tom Moss has a write-up on making a tester on his site (or he wrote an article on S+2B's site).

Good luck.
 
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