Super Jet Put in new rings and a higher comp head, comp seems low?

So my 62t only had about 130psi, so i decided to get the head milled by #zero and do some new rings and a light hone (pistons still were in great shape) got it all together today and just ran it in the water on the trailer for a few min to make sure it was working ok and there were no leaks, wich there wasnt, so i did a comp test to see how it was. it was 155/154, which seemed a little low to me being that its a 185psi head?

i know untill the rings seat that it will be a little low i just thought it would be higher than that?
Just wondering what you guys think?

-Jesse
 
Is there anything else you did you did but did not tell us about. Did the cylinder really need honing. How much material did they take? Did you home port? I like stock milled heads but not as much as ones with changeable domes
 
Break it in.... And Make sure you use a good comp tester. I had to rent one from autozone once When I forgot mine and it was reading 30 psi lower than my craftsman one.
 
ok. i thought it was a pretty nice craftsman guage, ill try my buddys snap-on to see if its any different.

it wasnt a hone really it was more less just a re-cross hatching of the cylinders. i set the ring gap to .022", and put it together. nothing else i did.

thanks for the help though guys. ill let you know what the other guage says.

-Jesse
 

OCD Solutions

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ok. i thought it was a pretty nice craftsman guage, ill try my buddys snap-on to see if its any different.

it wasnt a hone really it was more less just a re-cross hatching of the cylinders. i set the ring gap to .022", and put it together. nothing else i did.

thanks for the help though guys. ill let you know what the other guage says.

-Jesse

I agree with others about using the right gauge but I'm more interested in your ring gap. .022" seems pretty high for end gap. Out of spec on a stock bore 62T is .017" with ideal being something like .014".
 
you only had 130 PSi to start with, the head is milled to add 25 to 30 to 150 PSI right ?? I have same type of head and threw that on our ski 150/150 ended up having 180/180....
 
Tested it with my buddys snap on guage and is was exactly the same, 155.

Everything i could find said the ring gap was .022" for stock pistons/rings. my stock rings were also set at .022, maybe thats my problem all along? anybody can you confrim what the ring gap is saposed to be? I want to say the rings when i got them were at like .018" though.

I know the comp was a low before i re-ringed it, thats what i was hoping to fix with the rings.

thanks for the help guys!
-Jesse
 
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OCD Solutions

Original, Clean and Dependable Solutions
Location
Rentz, GA
Tested it with my buddys snap on guage and is was exactly the same, 155.

Everything i could find said the ring gap was .022" for stock pistons/rings. my stock rings were also set at .022, maybe thats my problem all along? anybody can you confrim what the ring gap is saposed to be? I want to say the rings when i got them were at like .018" though.

I know the comp was a low before i re-ringed it, thats what i was hoping to fix with the rings.

thanks for the help guys!
-Jesse

I just double checked 2 different manuals and both confirmed installed end gap to be .008 to .016".

Download this and see for yourself,
http://www.mediafire.com/view/?wn2njdykkyy
 

OCD Solutions

Original, Clean and Dependable Solutions
Location
Rentz, GA
Yup, I've made much, much more expensive mistakes...recently.

Now, you can still run it the way it is, it will just have slightly less compression until it warms up.

There was a thread a few years back that was nearly identical to this one, I searched last night but was never able to find it.
 
Went out and tested it today, went through about 1/4 tank in it, trying to dial in the fuel sum, it was better than it was for sure as far as throttle response anyway.

thanks for the help!

-Jesse
 
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