Compression test results

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TT5.9mag said:
How do the valve seals look? Are they umbrella type or positive locking type? Are they sitting down on the head or riding up at the keepers? Do they look ripped or torn?
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Ugh, got pulled away and didn't take the rockers off yet. Hopefully gonna pull within the next hour
 
You don’t have to pull the rockers. Just get a flashlight and look inside the springs.
 
TT5.9mag said:
You don’t have to pull the rockers. Just get a flashlight and look inside the springs.
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I can't make out the condition through the spring but did get a small glimpse. They look to be the same as the new ones I purchased from speedmaster
20211228_184617.jpg
 
The forum members are correct when they are telling you that throwing parts at it wont fix it. Hell 12 year old parts does not mean they are automaticly bad, my 67 Barracuda still has the original fuel tank.
One thing you may want to replace is that old 750cfm carb. I ran a 850 cfm carb on my BBM stroker and often thought it could have needed more cfm.
The correct size carb will make it easier to tune and better driving manners.
Food for thought.
If it is not blue smoking out the exhaust on a cold start up I would be reluctant to mess with the valve stem seals.
Clean up your fuel problem first to where you can get a good reading on fresh plugs and go from there, dont fix it if it aint broke.
 
GREEN GHOST said:
I can't make out the condition through the spring but did get a small glimpse. They look to be the same as the new ones I purchased from speedmaster View attachment 1715843790
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Unless they are trashed, which you’d be able to see, they are likely not a problem. Those are positive locking type seals. And if they’re torn during assembly they will leak oil past but they’re pretty durable. If they are all down on the guide boss and not visibly torn I’d not mess with em.
 
512Stroker said:
The forum members are correct when they are telling you that throwing parts at it wont fix it. Hell 12 year old parts does not mean they are automaticly bad, my 67 Barracuda still has the original fuel tank.
One thing you may want to replace is that old 750cfm carb. I ran a 850 cfm carb on my BBM stroker and often thought it could have needed more cfm.
The correct size carb will make it easier to tune and better driving manners.
Food for thought.
If it is not blue smoking out the exhaust on a cold start up I would be reluctant to mess with the valve stem seals.
Clean up your fuel problem first to where you can get a good reading on fresh plugs and go from there, dont fix it if it aint broke.
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Good advice. . .the 750 on it now is pretty trashed
 
TT5.9mag said:
Unless they are trashed, which you’d be able to see, they are likely not a problem. Those are positive locking type seals. And if they’re torn during assembly they will leak oil past but they’re pretty durable. If they are all down on the guide boss and not visibly torn I’d not mess with em.
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Think I should venture into taking a spring off to look or just leave it as is and move onto new plugs / fuel / timing . . .I can just see the red rubber part through spring but can't make out much else
 
If it means anything the guy that built the engines name is Dan herda from Florida. All I can find on the internet is that he ran a quick dakota. I spoke with some Florida's who apparently say he's well known ? Not sure
 
Carb looks so nasty. Previous owner said originally the engine was built with a 950 but he took it off for better fuel milage. He threw on this probably hand me down 750
20211228_195357.jpg
 
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I'd replace the plug wires, plugs and set the timing at 15 initial as a starting point.
Set mixture screws at a turn and half. fire it up
Then I would check for vacuum leaks and rule that out.
 
GREEN GHOST said:
Think I should venture into taking a spring off to look or just leave it as is and move onto new plugs / fuel / timing . . .I can just see the red rubber part through spring but can't make out much else
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My “opinion” is no. You dont know for a fact they are leaking. You do know for a fact that the carb is a problem. Rebuild carb, install new plugs, plug wires if the boots tore on disassembly, build a decent tune up in the carb and ignition timing. Drive and continue diagnostics
 
Really appreciate all the advice from everyone on this forum. . . Gonna work on tunning this thing up to try and get a decent baseline
 
Is the carb trashed or just ugly. It could be cleaned up good and a kit installed and be just fine. Much cheaper than a new carb. Go back with stock jets and go from there.
 
[1] Unfortunately, unlike Covid, no vaccine for Holleyitis. Best way to fix it is an Edel 800 AVS. Think about why an Edel/Carter carb is a mech sec carb, just like a DP, but does NOT need an acc pump on the secondaries to avoid bogging....
[2] Return spring routing as shown in post 84 is a reallllllly good way to wear out the pri throttle shaft. Return spring should hook to top of carb linkage & be anchored forward of the carb to equalise the 'pull'.
[3] I have a NGK catalog. The correct heat range plug is a 5, not a 6. You would only use a 6 or colder if you had very high CR, car was at WOT for sustained periods of time, was turboed/blown or used nitrous.
 
RustyRatRod said:
Simple trick to get hard to get to plugs out and in. Break them loose with "whatever" you can first, then get a length of fuel hose and slide over the end and turn them out. Reinstall them the same way. You can work right around header tubes like that. This is why it pays to put some kind of high temperature lubricant on the threads, so they will be easy to remove.
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You're the Real Deal RustyRatRod! Always a Slick Trick
 
aaronk785 said:
Is the carb trashed or just ugly. It could be cleaned up good and a kit installed and be just fine. Much cheaper than a new carb. Go back with stock jets and go from there.
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visibly is leaking and feels wet
 
aaronk785 said:
Street car or street strip or drag. Any thing above street I'd go 850
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Street 90% of the time. Probably make it to the strip a handful of times per year. . . Stop light to stop light fun
 
GREEN GHOST said:
Rather than mess around with the old carb I'm going to buy a new one and start fresh . After being on the phone with holley for 30min we narrowed it down to the two linked below. . What's everyone think ?

Quick Fuel BR-67331: Brawler Race Carburetor 750 CFM Mechanical Secondary / 4150 - Black/Red - JEGS High Performance

Quick Fuel BR-67201 Quick Fuel Brawler Race Series Carburetors | Summit Racing
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If you’re just dying to spend money get the 850. You already have a 750. But you will have learned nothing. What happens when you have to tune the new carb? (Hint, you will have to tune the new carb).
 
Bewy said:
[1] Unfortunately, unlike Covid, no vaccine for Holleyitis. Best way to fix it is an Edel 800 AVS. Think about why an Edel/Carter carb is a mech sec carb, just like a DP, but does NOT need an acc pump on the secondaries to avoid bogging....
[2] Return spring routing as shown in post 84 is a reallllllly good way to wear out the pri throttle shaft. Return spring should hook to top of carb linkage & be anchored forward of the carb to equalise the 'pull'.
[3] I have a NGK catalog. The correct heat range plug is a 5, not a 6. You would only use a 6 or colder if you had very high CR, car was at WOT for sustained periods of time, was turboed/blown or used nitrous.
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1.Nope
2. Valid point
3. His cranking compression suggests he is at the point of using a plug colder than the recommended plug for a stock engine.
 
GREEN GHOST said:
Rather than mess around with the old carb I'm going to buy a new one and start fresh . After being on the phone with holley for 30min we narrowed it down to the two linked below. . What's everyone think ?

Quick Fuel BR-67331: Brawler Race Carburetor 750 CFM Mechanical Secondary / 4150 - Black/Red - JEGS High Performance

Quick Fuel BR-67201 Quick Fuel Brawler Race Series Carburetors | Summit Racing
Click to expand...
Go with the 850, IMHO you are staving that engine for are air with anything smaller.
Hell I run an 800cfm carb on my 340 street engine.
 
TT5.9mag said:
If you’re just dying to spend money get the 850. You already have a 750. But you will have learned nothing. What happens when you have to tune the new carb? (Hint, you will have to tune the new carb).
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I hear ya, maybe I can run it quick with the 750 when the plugs / wires are back on to diagnose. The throw the 850 on & tune it. . .just not into trying to rebuild the 750 . ..it look pretty trashed
 
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