Where to buy an Anti-pullover diaphram?

[SHARPY27]

Can someone please tell me where to get one of these? Is Joe still making them? Anybody have a phone #?????? HELP, PLEASE!!! LOL

[500BOMBER]

They have those at Auto Zone, right next to the Yugo muffler bearings.

[TR32]

And the piston kick back springs............

[return to dirt]

sharpy, i think joe has retired. after work tonight i will post how i make mine using an umbrella valve stem seal.

olin

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sorry, got busy last night and didn't get back here. the pump diaphrams joe made had a valve stem seal glued to the diaphram. it was a small positive type seal. i use an umbrella seal, the type with a smooth curve and not a sharp curve. take and cut about half off the bottom and place it on top of the diaphram with the stem hole towards the orange flapper valve. you may have to make a few until get the size correct. you don't want it to touch the flapper valve when you are off the throttle so the pump housing can fill with fuel. when you step on the gas and the diaphram is moved up towards the bowl the valve seal will contact the flapper valve and hold it closed sealing the refill holes. this will stop all vibration induced pullover from half throttle on. you can adjust the point of contact by changing the thickness of the valve seal. you may have to change the flapper valve every year but i have ran them for up to 2 years without a problem. the ones joe made were high tech. i had 2 or 3 and one finally failed after 3 years but the others still work although i had to replace the flapper valves on them. hope this helps.

olin

[return to dirt]

They have those at Auto Zone, right next to the Yugo muffler bearings.

that's good, those are next to the diesel exhaust fluid and the stretchy belt installer. wait, these two are real just like the anti-pullover diaphram.

olin

[RACEMAN]

sorry, got busy last night and didn't get back here. the pump diaphrams joe made had a valve stem seal glued to the diaphram. it was a small positive type seal. i use an umbrella seal, the type with a smooth curve and not a sharp curve. take and cut about half off the bottom and place it on top of the diaphram with the stem hole towards the orange flapper valve. you may have to make a few until get the size correct. you don't want it to touch the flapper valve when you are off the throttle so the pump housing can fill with fuel. when you step on the gas and the diaphram is moved up towards the bowl the valve seal will contact the flapper valve and hold it closed sealing the refill holes. this will stop all vibration induced pullover from half throttle on. you can adjust the point of contact by changing the thickness of the valve seal. you may have to change the flapper valve every year but i have ran them for up to 2 years without a problem. the ones joe made were high tech. i had 2 or 3 and one finally failed after 3 years but the others still work although i had to replace the flapper valves on them. hope this helps.

olin

Olin,

Any chance of you posting or sending some pics of what you created. Thanks.

Mike

[1195]

Jet size

Olin
After you get the vibration induced pullover stopped how many jet sizes do you need to incease.
Thanks Steve

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mike,
i'll try to get some pictures on here if i can. give me a day or two as i have racing tonight and i'm the tech man so i have to be there. would rather be racing but am helping the track to try to stay open.

steve,
i usually go by what holley posts on their site and then go up a couple of sizes. be sure to read your plugs. my toyota mods 500 had pullover so bad i plugged off the pv and went down to 65s to keep it from blubbering until i got one of joe's diaphrams.

olin

[return to dirt]

i have never tried this to correct vacuum induced pullover which is more of a v8 problem but i would believe it would work for that as well. when i switched my toyota mod over to a 390 double pumper i used this in both bowls and never had a problem. i've ran this on both ford and toyotas. my fords have used both jbv intake and adaptor and stock carbed intakes with 350 and 500 carbs with no problems. my 20r/22r hybred mod has used both ported stock intakes and holley street dominator intakes with 500 2bbl and 390dp 4bbl carbs with no problems.

olin

[SHARPY27]

Thanks for the info, Olin. Will give that a try.

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still working on pictures. went to the computor expert in the house, my wife. we all know how that turns out.

olin

[wil8115]

http://www.stockcarracing.com/techarticles/scrp_0508_carburetor_cures/

like this?

[return to dirt]

same basic idea. instead of using a hard rubber coated steel washer i used the umbrella seai. it's softer and is easy to use. i'm still trying to get some pictures.

olin

[Racedad]

Another way with no glue.

I use the 7mm umbrella seal without the glue.I machine a flat groove in the bowl with the OD just inside the spring pocket but with the ID big enough to clear the checkvalve(mine has a checkball not a red flapper type).Then I shorten the valve seal so it is just tall enough for the top to be even with the gasket surface.Cut it off with a razor blade bit you need to sand it flat on a disk sander after cutting it off.

Gas can get in when off the gas and it seals after you get on it. It always goes back to center when it closes no problem.You will need to adjust it so you get a pump shot and yet it shuts down the pullover after 1/2 throttle or so.

These will take away a lot of your 35cc or whatever pump capacity but it still seems enough.I suppose if you had a single pumper V8 application you would need the 50cc unit for sure.

I run a 4412 with a power valve block off with 74 jets on a 2.5.