just did a compression test. what do you think?

[cenok is family]

ok, i just did a dry compression test a few hours ago and here's what i got:

#1: 152
#2: 165
#3: 160
#4: 165
#5: 162
#6: 160
#7: 160
#8: 150

when i did this, i disconnected the the harness going into the enertia switch as well as some other harness going into some other thing in the same place as the enertia switch except on the opposite (right) side. didn't know what it is but wanted to make sure no fuel was getting to my motor durring testing. also, i pulled the coil wire and all the plugs. motor was warmed up but it took me so long to get everything ready that it cooled down some by the time i started. and i had a battery charger hooked up to make sure it was turning over the same each time. i'm gonna try and get a leak down test done on her this coming weekend hopefully. also my car's really leaned out, fp is at 32 w/vac line connected. no oil on my plugs except a little bit on the threads on a few of them. they're just white. if i turn my fp up any more, my car falls on its face at wot. timing is at 13* or 14*, dont remember exactly. what do you guys think?

for more info, here's my other thread about my problems:
http://forums.stangnet.com/showthread.php?t=720416

thanks a ton to all that have helped.

 

[cenok is family]

ttt

 

[blackened88lx]

Sounds alright. 1 & 8 are a little lower than the others, but not terrible. Did you do the test at WOT? Also, how long did it take for them to reach full compression?

 

[Freak Stang]

Those readings are fine. As long as the highest and lowest are within 10 percent you are OK.

 

[cenok is family]

Sounds alright. 1 & 8 are a little lower than the others, but not terrible. Did you do the test at WOT? Also, how long did it take for them to reach full compression?

yeah i did it at WOT. they took about 2 or 3 strokes before they were full compression. is that normal?

 

[rj95svt]

After reading your other thread I think that your valve stem seals need replacing. Compression looks to be good.

 

[SVT32VDOHC]

If it ain't broke, don't fix it!!!

Numbers look close enough. How's it run?

 

[blackened88lx]

yeah i did it at WOT. they took about 2 or 3 strokes before they were full compression. is that normal?

Yeah, sounds good.

 

[65ShelbyClone]

Those readings are fine. As long as the highest and lowest are within 10 percent you are OK.

That's only half of it; the compression also has to be above a minimum pressure. I forgot what the manual says, but I thinks it's in the 120 range.

150psi+ and a 9% spread isn't bad, but I agree that #s 1 & 8 are a little low.

What kind of rings did you get? I got standard Hastings iron rings when I put together my roller 302(in the '68) and they mostly seated before I ever got the car out for a test drive. I never checked the compression on it, though.

By the way, flooring the gas before and during cranking will tell the ECU to enter flood clear mode where it shuts off the injectors. It's common to forget you can do that without unplugging half the fuel system. If the car starts up when trying that, the TPS needs adjustment. (don't blow it up or anything)

 

[cenok is family]

If it ain't broke, don't fix it!!!

Numbers look close enough. How's it run?

it runs good, but not as good as it should be. especially after it warms up. but i can't tell if it's just a tuning issue, or something is actually wrong. btw, how's the mod swap going?

After reading your other thread I think that your valve stem seals need replacing. Compression looks to be good.

how much do valve stem seals normally cost to get replaced?

That's only half of it; the compression also has to be above a minimum pressure. I forgot what the manual says, but I thinks it's in the 120 range.

150psi+ and a 9% spread isn't bad, but I agree that #s 1 & 8 are a little low.

What kind of rings did you get? I got standard Hastings iron rings when I put together my roller 302(in the '68) and they mostly seated before I ever got the car out for a test drive. I never checked the compression on it, though.

By the way, flooring the gas before and during cranking will tell the ECU to enter flood clear mode where it shuts off the injectors. It's common to forget you can do that without unplugging half the fuel system. If the car starts up when trying that, the TPS needs adjustment. (don't blow it up or anything)

i have moly Power Seal rings. they're 1/16, 1/16, 3/16 if that matters. man, i wish i knew about that flood clear mode thing before i rebuilt my motor...my car ran PIG rich because of some broke wires on the TPS and would flood itself out if i drove it for more than 20 mins. if i turned it off, i'd have to sit and wait another 30 mins to an hour before it would start again! very frustrating....i'm glad it doesn't do that anymore!

 

[rj95svt]

I am unsure as to the cost of replacing the valve stem seal with the heads on the car the seals themselves aren't very expensive but each cylinder will have to be filled compressed air to hold the valves closed and the valve springs will have to be pyulled one by one to replace the seals. Personally I would just install some aftermarket heads instead of going through the trouble.

 

[65ShelbyClone]

i have moly Power Seal rings. they're 1/16, 1/16, 3/16 if that matters. man, i wish i knew about that flood clear mode thing before i rebuilt my motor...my car ran PIG rich because of some broke wires on the TPS and would flood itself out if i drove it for more than 20 mins. if i turned it off, i'd have to sit and wait another 30 mins to an hour before it would start again! very frustrating....i'm glad it doesn't do that anymore!

It does matter; moly rings supposedly take longer to break in than iron. How much longer I don't know. I hear that the honing has to be more agressive too, but I also can't verify that. That might have something to do with the compression numbers. Not they're bad, a few are just a hair lower than I'd expect for a fresh engine.

It's actually good you didn't try the flood clear mode when your TPS had broken wires. Since the ECU couldn't know when you were flooring the gas, it would have gunned the engine instead of shutting off the fuel. Like I said, the TPS has to be adjusted and working properly for flood clear to work.

 

[rj95svt]

It does matter; moly rings supposedly take longer to break in than iron. How much longer I don't know. I hear that the honing has to be more agressive too, but I also can't verify that. That might have something to do with the compression numbers. Not they're bad, a few are just a hair lower than I'd expect for a fresh engine.

It's actually good you didn't try the flood clear mode when your TPS had broken wires. Since the ECU couldn't know when you were flooring the gas, it would have gunned the engine instead of shutting off the fuel. Like I said, the TPS has to be adjusted and working properly for flood clear to work.

I agree with this but he didn't replace the valve seals on stock e7 heads. He said in his other thread that the heads only had around 11,000 miles (some real low number) but since e7 heads haven't been made since 95 the valve seals are atleast 12 years old are more than likely atleast part of the problem.

 

[65ShelbyClone]

I was talking about the compression numbers in this thread, not the oil usage in the other thread.

 

[rj95svt]

Oh I was thinking the whole point of both threads was to figure out why his car was using oil.

 

[cenok is family]

Oh I was thinking the whole point of both threads was to figure out why his car was using oil.

yeah it is. but any other info or advice is gladly welcomed as well.

so the conclusion is i should get some baffled valve covers and have a leak down done?

thanks guys!