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Advance springs issue...

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Old Nov 2, 2005 | 11:21 PM
  #21  
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From: pr, frederick md.
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IMHO, i think we are all missing the real problem here. he stated he used GOLD springs. these are NOT the " strongest " or " heaviest spring " . the black ones are. every kit ive ever seen anywhere, goes 1. black 2. silver 3. gold. heavy to light. so he's using the lightest spring. moroso has a kit with more colors, and spring rates, but the black is still the " strongest" and " heaviest". just my .02
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Old Nov 3, 2005 | 10:47 AM
  #22  
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Actually, I'm not sure what cam I am using, but as far as I can see,
it seems to be the stock cam for a L-82 350CI : I've got stock rockers,
hydraulic lifters ( I saw them when I dismounted the intake manifold )
and pushrods, so it should also be stock camshaft ?
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Old Nov 3, 2005 | 10:15 PM
  #23  
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Originally Posted by 73StreetRace
Actually, I'm not sure what cam I am using, but as far as I can see,
it seems to be the stock cam for a L-82 350CI : I've got stock rockers,
hydraulic lifters ( I saw them when I dismounted the intake manifold )
and pushrods, so it should also be stock camshaft ?
If it is the stock cam, you have problems if you only have about 13" vacuum. Healthy engine with stock cam should be about 19-20". Vacuum leak, worn engine, ?. What is your cranking compression?
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Old Nov 4, 2005 | 11:59 AM
  #24  
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No, glen242 !
I get low manifold vacuum at idle because I have a single plane manifold ( Holley street dominator ), which gives torque and power over 3500 RPM ( as Lars told me ).
With single plane manifolds, it is normal to get less vacuum than with dual plane manifolds.
I already posted about this point, and some other people used to get the same results with approximately the same configuration.
I changed all the manifold gaskets last year, and trust me, I don't have any vacuum leak between manifold and headers/engine.
My PCV valve is new and works correctly. All engine hoses are new. ( included vacuum hoses )
The headlight panels can still be open 2 days after the last use of the car, so there is no leak at the vacuum tank too.
For information, I get between 160 PSI and 165 PSI compression on all cylinders ( 11.0 to 11.5 Kg/cm2 ).
I don't think I have a worn engine, as it burns absolutely no oil at all, and I never get blue smoke at exhaust...
The color of all 8 spark plugs is perfect ( so no worn rings signs ).
If you insist, I will post a picture of my engine, but don't forget to wear your sunglasses
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Old Nov 4, 2005 | 03:26 PM
  #25  
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Originally Posted by lars
122-71 and 122-78


Yes


Remove the bowl, unscrews the jets, install new ones, install the bowl.


You may need a new float bowl gasket if the old one tears upon disassembly. Good to have a few spares on hand if you're going to be doing tuning.
Wouldn't you just love to have, Lars, as a neighbor. He's already forgotten more than I'll ever know. Larry
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Old Nov 5, 2005 | 12:26 AM
  #26  
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Originally Posted by 73StreetRace
No, glen242 !
I get low manifold vacuum at idle because I have a single plane manifold ( Holley street dominator ), which gives torque and power over 3500 RPM ( as Lars told me ).
With single plane manifolds, it is normal to get less vacuum than with dual plane manifolds.
I already posted about this point, and some other people used to get the same results with approximately the same configuration.
I changed all the manifold gaskets last year, and trust me, I don't have any vacuum leak between manifold and headers/engine.
My PCV valve is new and works correctly. All engine hoses are new. ( included vacuum hoses )
The headlight panels can still be open 2 days after the last use of the car, so there is no leak at the vacuum tank too.
For information, I get between 160 PSI and 165 PSI compression on all cylinders ( 11.0 to 11.5 Kg/cm2 ).
I don't think I have a worn engine, as it burns absolutely no oil at all, and I never get blue smoke at exhaust...
The color of all 8 spark plugs is perfect ( so no worn rings signs ).
If you insist, I will post a picture of my engine, but don't forget to wear your sunglasses
I did not know the intake manifold design, single or dual plane, affected the manifold vacuum at idle. I thought manifold vacuum was only related to engine internals. I got my info from reading the instructions that came with the vacuum gauge. I guess if Lars confirmed this, I'll take it as gospel, but I don't understand the mechanics of it.

BTW, Holley.com only lists the Street Dominator as a dual plane not a single plane.
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