post your gas saving tips
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Race Director
Joined: Oct 2000
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From: central FL, near the beach.
anyone that "tests" this should plan on a tig weld if their combo like it.
there are tremendous sonic shocks that i suspect would spit out silicone in a much shorter time than epoxy. i've used jbweld inside my manifold for 5+ years. it will fail someday
but is great for testing ideas.
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Race Director
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From: central FL, near the beach.
watch out for carb ports! the holley power valve has a 1/8" hole and must not get blocked.
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From: Dayton, Ohio
Another thought-If some mesh or screen was cut and put in the epoxy it might stay together if it ever cracked.
Burning Brakes
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From: Sarasota Florida
i have an edelbrock 1406 600 cfm, and the design is a little different underneath. wouldn't you lose power or wouldn't it be bad for the motor if the power steering or PCV takes an unequal amount of vacuum from both sides of the engine?
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Race Director
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From: central FL, near the beach.
on my 61 i just epoxied over that screw. epoxy can be removed with heat, a match or a small torch will soften it. JB Weld claims it takes 600F. Easily exceeded with a match 
.
i went thru my junk carb pile, and some leak LOTS -holley 4011 awful.
others are not too bad.
But, they all get worse with a 2 hole manifold. They appear to be designed for a stock 4 holer.
I used to blame poor mpg on the cam, now i'd say much of the loss was the 2 hole manifold! So, guys, depending on your carb, a 4 hole plate could stop about half the internal leakage, without any epoxy. Post pics of what u have.
.
i went thru my junk carb pile, and some leak LOTS -holley 4011 awful.
others are not too bad.
But, they all get worse with a 2 hole manifold. They appear to be designed for a stock 4 holer.
I used to blame poor mpg on the cam, now i'd say much of the loss was the 2 hole manifold! So, guys, depending on your carb, a 4 hole plate could stop about half the internal leakage, without any epoxy. Post pics of what u have.
Thread Starter
Race Director
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From: central FL, near the beach.
This is not an ALL or NONE mod.
u could reduce the leakage to say, 1/4" or so, and still get most of the improvement, while maintaining 8cyl brakes/pcv
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Thread Starter
Race Director
Joined: Oct 2000
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From: central FL, near the beach.
Thread Starter
Race Director
Joined: Oct 2000
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From: central FL, near the beach.
so tell me why they made it the way they did?
Would this mod help that car? How could it? It had a stock 4 hole manifold. it got 17.6. That is good.
This topic is about a c3 that once got 17, was modded, and now gets 9-12. what went wrong? Sure the owner has a job and can afford it. But, he is dumping gas down the sewer for no reason.
Last edited by Matt Gruber; Nov 11, 2007 at 01:36 PM.
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
With an LM-1 wideband O2 sensor and a overdrive tranny I get over 25MPG on the highway with a 550HP small block. The only way you are going to get your motor tuned correctly is with a wideband 
Last edited by MotorHead; Nov 11, 2007 at 04:55 PM.
Burning Brakes
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From: Sherwood Park AB
Where are these ports on a Q-Jet? Can the mod be done for a Performer dual plane intake?
Does the O2 sensor go in the collector of the header or can it go in the exhaust pipe? My headers are ceramic coated.
Does the O2 sensor go in the collector of the header or can it go in the exhaust pipe? My headers are ceramic coated.
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Former Vendor
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From: walpole ma
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Drifting
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What does an O2 sensor do to a motor with no computer?
Do you have to have fuel injection or something?
You have me very interested...
I might believe the 25mpg with the overdrive tranny, but I don't get the O2 sensor.
Burning Brakes
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From: Sherwood Park AB
Race Director
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
No I am not joking and 25mpg @ 80mph too, engine is turning 2000RPM's
With a wideband O2 sensor you can adjust you fuel mixture correctly for idle, cruise and WOT, and get pretty much the same results as fuel injection. Without a wideband you can't tune correctly and you are probably getting crappy gas mileage
With a wideband O2 sensor you can adjust you fuel mixture correctly for idle, cruise and WOT, and get pretty much the same results as fuel injection. Without a wideband you can't tune correctly and you are probably getting crappy gas mileage