Leak Down and Compression Questions

[voidfinger]

Ok guys i know someone in here knows a little about what numbers these things suppose to be at. I've looked over some search engines and picked up nothing but questions...

1) What are the compression readings suppose to be on these motors? Like in lbs like the gauges read.

2) What is the acceptable leak down rate of these motors? I've found like 4 different answers on the web.

Thanks guys

Mitchell

 

[Jrgunn5150]

1. Around 170, but you are really looking more to see if there is a huge variance.

2. No more than 15%.

 

[voidfinger]

ok i did a cr check like 5 months ago and it was like 160 on all the passengers side and the drivers side was like 165-170-165-165 from front to back. or it might have been closer to 170 but one was 165. I was told a while back that if one side was way off and around the same numbers then it could be a miss timed cam... ?

and 15% thats hot right?

 

[Jrgunn5150]

If there's a side to side difference, but the number's are consistent on each side, then it could be a cam, or you have a head milled more than another, or something goofy like that.

15% is cold, but that would be like rebuild now time.

 

[voidfinger]

hmmm, everyplace i saw on the net said that it was like 25% and that it.. even one said that he checked a couple new cars with less than 10k on it and 20/25 was the standard number... hmmm

 

[Jrgunn5150]

Wow, lol.