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Old 11-06-18, 07:51PM   #106
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Not doughting anybodys word here, thinking outside the box, i posted those once before and everyone seemed to say not to bad at all, 10-1 compression the things ive read if its within 20% of each other its ok. So may i ask should they all be close to 190 then?? You mentioned valve job. How can i tell if thats causing me the issue,s??
I don't think your numbers are bad at all Rich, my 400 is around 170-175psi per hole and it moves my 3950lb tank at 11.5 @ 118. The cam makes a difference in static compression too, you've changed that since your last comp test. A leak test would probably tell you more though.
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Old 11-06-18, 08:02PM   #107
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With a leak down test, youíll be able to tell if itís leaking by the valves or the rings. Dude you should have 190-185 in all cylinders. ring and valve seal is the key to making power. 165 in that one cylinders is bad. Iím actually surprised you pick up any ET at all.

With the new cam, your making more cylinder Pressure, usually if the rings are on their way out, the added cylinder pressure will make the issue worse.
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Old 11-06-18, 09:25PM   #108
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Asked about a compression test, I warmed up the Gt0 125 degree,s, All plugs removed , Q-jet throttle wide open and here are my results: Not bad after 8 seasons: No1 180 No8 190 No4 180 No3 165 No6 170 No5 175 No7 170 & no 2 190 No 3 is questionable but really not that bad. I believe motor is coming out this winter. Its been a great ride, no complaints. Tons of fun. Hay ill need something else to fool around with next year.
KrisR did you read this? No-8 is 190...No.-2 190. But No.-3 is only 165. So this tells me they all should be around 185-190. The companion cylinder No-6 is only 170.

5-10 lb drop is exceptable. But 20-25 in 4 cylinders...not good.
If he hasnít touched it in 8 years my guess itís ring seal gone away.

I think the heads were freshly done last year, when he put the longer valves in.
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Old 11-06-18, 09:32PM   #109
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If he didnít care and was just bracket raceing wouldnít be a big deal, but heís got his heart set on running solid 11ís.
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Old 11-06-18, 09:55PM   #110
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KrisR did you read this? No-8 is 190...No.-2 190. But No.-3 is only 165. So this tells me they all should be around 185-190. The companion cylinder No-6 is only 170.

5-10 lb drop is exceptable. But 20-25 in 4 cylinders...not good.
If he hasnít touched it in 8 years my guess itís ring seal gone away.

I think the heads were freshly done last year, when he put the longer valves in.
Yep no doubt it's a little worn. I just don't get too hung up on static cyl pressure when so many things can affect it and whether each cylinder was tested more than once (i.e. repeatable). It's his car/money/time/effort/problem in the end.
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Old 11-07-18, 01:42AM   #111
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Correct...he’s looking for answers.
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Old 11-07-18, 12:05PM   #112
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The 165 psi number is low when you think about Rich let the car warm up to 120 deg Why I don’t no. But with a warm engine rich should had a higher reading on #3 and others. He can do a wet test on #3 and see if the compression improves. But I think is not the rings. Remember last year when Rich was trying to do a leakdown test he said he removed all rockers ( that’s when he found 5 upside down ) and removed his intake then pressurized the cylinders and did hear air coming out one or more cylinders. Air coming out the intake port makes me think intake valve or valves. Rich try putting a little oil in #3 and do a compression test see if it inproves.
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Old 11-07-18, 01:07PM   #113
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I remember that, but thought that issue had been resolved. Donít know who told him 20%, it should never be more then 10%.
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Old 11-07-18, 01:24PM   #114
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You should run the engine up to temperature then let it cool for a hour before you do compression test.

Put like a teaspoon of oil in number 3. Then retest, see if compression comes up, if it does then itís rings. If not itís valves.
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Old 11-07-18, 10:07PM   #115
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Heís a low budget racer just having fun. I doubt heíd want to spend the money.
How much was spent on those edelbrock heads?
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Old 11-08-18, 12:26AM   #116
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Enough...lol heís retiring 400, not that it wouldnít do the trick, just going to build a good short block with steel rods. Iím just curious whatís causing low compression, valves or rings.
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Old 11-08-18, 07:44AM   #117
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Lou I may have to rethink the valve or valves leaking. Rich replaced his spring with the cam change I’m thinking rich replaced them with the heads on the engine which would have him the need to presurize the cylinders for some time for each cylinder..I beleave he would of hear something in all that time. So I don’t know ?
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Old 11-09-18, 05:57PM   #118
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Fella,s your making to much out of this little 400 motor bracket car, just something to go out and run every weekend if needed and not break anything. I have done just that , If i was retired i would be out alot more. Its been a blast, Side beam polished rods held up better than all the motors ive seen scattered down a Normal Pontiac Sunday afternoon. Rpm intake with a rebuilt q-jet going 11.90,s while the guys next to me are bragging about there Roller cammed motors going 11.70,s. I have a Crower Hydraulic cam keeping almost up with the best of the guys. Do i personally fill there,s more here. sure i do just my opinion thats does not mean a thing. Would i like to see 11.70,s sure but my goal has been reached.
During the upcoming months there will be a motor change & i can tear old faithfull down and take a look at her. any regrets NOT a one. Thanks everyone for your input.
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Old 11-09-18, 07:33PM   #119
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Fella,s your making to much out of this little 400 motor bracket car
Can’t stop laughing, your the one who post up, when your having issues. Now your kind of Marking those trying to help.

Rich, I wouldn’t be bragging if I were you ( at least in my mind ) that’s how you come off. Kind of like belittling those who make suggestions about the issues your having
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Old 11-09-18, 07:48PM   #120
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They donít call you Mr Pontiac for nothing...LOL As long as your having fun thatís all that counts.
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