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Rechecked I'm running a strong 9g at idle .Who would have guessed.?11° to 12° initial at about 650-700..How many teeth on a FE distributor gear? I'll order more powervalves tomorrow in 6.5g and 7.5g . Right now it looks like a 6.5G valve would work better.testing will tell more later.
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Mike,
Hook up your vacuum guage so you can see it when you drive. Drive the car and observe the lowest vacuum reading at cruise. That is where you get the number that determines the power valve spec. now subtract 2 from that number. that gives you the power valve number. I'm not sure just checking the idle reading will give you the whole story. Steve |
Quick Fuel techknowogy said in gear .I wasn't sure what they ment.
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Mike,
They are talking about a car with an automatic transmission. You are so close to getting that car running right, I can smell the burning rubber from Texas. :3DSMILE: |
I took the car for a ride vacum hose from under the rear carb ,over the windsheild and vacum gauge hanging form passenger grab handle.With engine running the lowest vacumwas 9 any thing like maintaining speed ,was even higher.But as you said I had a rich idle or something .You could tell it was starting to miss a little and even when we got home and it was running ruff it could hold 8.I called Quick Fuel Techknology and they insist that maybe a 4.5,Not to go any higher.But it is running rich enough to foul plugs.It just took longer this time.And that is another thing.What plugs are you using ? Mine came with Boush Platinums.When I tried these years ago in a Land Cruiser they fouled faster than any plugs I had tried before or since.For the Land Cruiser I ended up with NGKs.I may end up drilling the throttle plates yet.I'm wondering about the jets .As I remember I'm running 68s, the carbs were to have come from the factory with 67s When I brought it from Reno it had 64s But emmissions said it had a lean misfire resulting in high unburnt hydocarbons.I'm almost lost .what direction to go next and I have to put every thing away ,empty and clean the garage for canning next weekend.Had a tree cut down ,Got all the woodmsplit and hauled tp camping lot. not I have to remove the stump next to the hot tub gazebo.The roots are as big as the tree.And I have to help my son roof and side his new garage.No moss on this rolling stone.
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Mike,
TELL YOU SON TO ROOF IS OWN D#$M GARAGE. GET A HOLD OF YOURSELF MAN! Anyways, yesterday, after reading your vacuum results I checked my vacuum. At idle it was around 9.5. Cruising down the flat road at 45 or 50 it was around 8 or so. Light to moderate accelerations reveiled readings down to 5 or 6. I have had great luck with Autolite plugs. For some reason, they have been less prone to fouling on engines I have owned. As for that stump, find some termites and let 'em do their thing :p Mike, Go here http://www.bob2000.com/carb.htm and print out the entire article. Now locate it next to your favorite crapper. Every time nature calls, (#2) read it, love it, live it. It will expand your head so much it will barely fit throught the door frame. Below is an excerpt out of it about drilling those holes in the throttle flys: "Another common cause of non-responsive idle mixture screws is having too much (more than .040 inch) of the idle transfer circuit exposed. The idle circuit allows a very small amount of finely metered fuel into the engine. By exposing the transfer circuit too much, the gross feed of fuel coming out of the transfer circuit overpowers the fine amount coming out of the idle ports. This is akin to adding a squirt gun's flow into a garden hose's flow...the fine amount of the squirt gun is so insignificant compared to the garden hose, that there is no way that adjusting the flow of the squirt gun will make any difference. There are several ways to fix this problem: 1. If your engine is worn, or has a big vacuum leak, you should fix those problems before trying to crutch your carb. Sometimes, with worn engines or one with a vacuum leak, the carb must be opened quite a bit just to get the engine to run. 2. Buy the right sized carb! If you're trying to use a 600 cfm carb on a lopey-cammed 460, then you must open the primaries too far into the transfer slots just to get enough air into the engine to get it to idle. A larger carb on this example would have a larger throttle plate, which would need to opened less to allow the engine to idle. 3. Open the secondaries a bit, and close the primaries a like amount. This will allow more air in, without exposing quite so much of either primary or secondary transfer slots. 4. If opening the secondaries doesn't work, then you may have to drill small holes (1 per plate) in the primary throttle plates to allow air in while the plates cover the transfer slots. This is a trial and error procedure, so start small, about 1/16 inch. You should not have to go much larger than 3/16 inch. Drill on the side opposite of the transfer slots, to help keep this added airflow away from the idle ports and transfer slots. " |
I have a fresh 427 .020 "over, Dove alluminum replica of Canandian Super Cobra Jet heads and A Dove alluminum tunnel wedge 2x4 intake manifold.Two 600 cfm Holley 4160 carbs.No holes drilled yet.
I installed a pair of 50cc accelerater pumps while thing were appart. They appeared to have the same levers as originals so they would accept larger accelerater cams with more travel.I haven't changed any cams yet so that should be the same. The Cam shaft is close to what I had before .It is Comp Cams solid lifter 242° intake 252° exhaust .598" lift It had 4 °advance built in so It was timed straight up. I changed the Ignition Box because the older Mallory unit didn't have any rev limiting capability.The new Mallory VI has Two programable rpm limiters and the second lower rpm can be turned on with a switch.Also I can program in an automatic start retard.I programed in 8° that it holds out under 500 rpm. When its started and ideling inital timing is set at 12°. |
FOCUS! MIKE, FOCUS! THINK THROTTLE PLATES AND 3.5 POWER VALVES!!!!! :CRY:
ps While cruising around today I noted my vacuum at 5 when running down the highway (no hills) in 5th gear @ 1800rpm. Do you have a 4 spd or a 5 spd? Steve |
4spd, 3.56 gear
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Maybe the 4.5's would be better in your case.
Steve |
Question .Without changing any of the plastic accelerater pump cams ,would the 50 cc accelerater pump kit change the volume? I changed over to the 50 cc kits when the engine was down. It appeared that the new levers had the same lengths and that the new housing and diaphram would accomodate more travel if I were to replace the plastic accelersater cams with some of the larger ones later .
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I'm wondering where to start.Gerald mentions removing carb, screwing nuts back on studs and setting the carb on the studs with a space underneath to view. and rehooking up fuel supply and looking under carb to see if fuel is running.He mentions opening secondaries a little to feed a little air through their idle circuit. I know there is an idle circuit that is sopposed to be taking fuel out of the seconary fuel bowl so it doesn't get stale.I wonder if he ment on a 4160 series without secondary metering plate, no adjustments? He didn't mention dual carbs. and didn't mention any drilling.It worked before.What did I do to screw it up.
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The secondaries should be open just a touch. I just went through all this on a 521 I just built. It wouldn't idle well until I opened the secondaries a bit. Just make sure the transfer slot is not uncovered. If it is, then drill the throttle blades. Very rarely do they need the holes drilled. Usually only on engines with a lot of cam overlap. I can't see any use for the 50cc pumps on your carbs. Remember, there are two pumps feeding your engine, not one like most. Go back and try the std pumps, but be sure they are properly adjusted and don't bottom out. Try jets around #60 to #68
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Mike,
Quote: "FOCUS! MIKE, FOCUS! THINK THROTTLE PLATES AND 3.5 POWER VALVES!!!!! "... I'm the one who needs to focus! :o I didn't see that you already installed 3.5's... my name is "DuMass":eek: I'm with David on the acceleraor pumps. I don't think you need the big ones. He is right, a better approach to messing with the idle would be to adjust the 2ndary throttle plates to see if that will achieve the desired effect before drilling. Removing the carb and looking for leaks is to check for a blown power valve. I doubt your new valves are blown, but that check couldn't hurt. You say you got the idle down to 600 RPM? Is it a smooth or rough idle? |
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