351w engine
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New User
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351w engine
Recently installed a rebuilt NAPA 351w engine in a 1985 F250. First I had a tap in the motor, thought it was a loose valve, turned out to be the fuel pump, the rebuilder put the wrong fuel pump cam on the timing chain gear, watch out guys! the cam should be a full circle!!
Took the cam off and used an electric fuel pump.
Motor starts fine, idles fine but seems sluggish climbing a hill or snow plowing.
The electric pump should have enough pressure (4-7 lbs) for an Edelbrock 4 barrel carb.
Played with the timing, new plugs, new air filter, new fuel filters.
No vacuum leaks.
By the way if using an Edelbrock carb, the left hand vacuum port on the carb
(facing the carb) is more responsive than the right hand port and seems better for distributor vacuum advance. Oh, also installed a rebuilt distributor.
Any suggestions?
Thanks
Took the cam off and used an electric fuel pump.
Motor starts fine, idles fine but seems sluggish climbing a hill or snow plowing.
The electric pump should have enough pressure (4-7 lbs) for an Edelbrock 4 barrel carb.
Played with the timing, new plugs, new air filter, new fuel filters.
No vacuum leaks.
By the way if using an Edelbrock carb, the left hand vacuum port on the carb
(facing the carb) is more responsive than the right hand port and seems better for distributor vacuum advance. Oh, also installed a rebuilt distributor.
Any suggestions?
Thanks
Postmaster
Joined: Jun 2005
Posts: 2,656
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how does it idle.... I'll say it again.... try the 302 firing order..... a lot of times they just throw what ever they have on the shelf or what is cheaper... same cam just different firing order. worth a try.....seen it fix a few of them....
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Thanks for the replys.
The motor starts and idles fine.
Actually with the electric fuel pump, it starts much easier in cold weather, even at 5 degrees, don' have to pump the accelerator about 20 times anymore.
Installed new autolite plugs and checked the gap.
May try the 302 firing order, can't say that I have ever heard of that happening, but it's worth a try.
Plan to put a fuel pressure regulator on. Don't smell gas at the carb or nor is it flooding.
Thanks again.
The motor starts and idles fine.
Actually with the electric fuel pump, it starts much easier in cold weather, even at 5 degrees, don' have to pump the accelerator about 20 times anymore.
Installed new autolite plugs and checked the gap.
May try the 302 firing order, can't say that I have ever heard of that happening, but it's worth a try.
Plan to put a fuel pressure regulator on. Don't smell gas at the carb or nor is it flooding.
Thanks again.
New User
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Originally Posted by HemiEater
how does it idle.... I'll say it again.... try the 302 firing order..... a lot of times they just throw what ever they have on the shelf or what is cheaper... same cam just different firing order. worth a try.....seen it fix a few of them....
ok you do realize that the cam and crank both dictate the firring order? if the crank is right and the cam isnt no matter what order you fire the plugs in it's going to be screwwed. the crank and cam both have to be for the same firring order, if they are not the same i bet it wouldnt even run
the 351w HAS the same firring order as a HO 302, the regualar 302 has a different firring order
Lead Driver
Joined: Aug 2002
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From: Saskatoon SK Canada
Just the crankshaft is the same for the HO and regular 302s. The camshaft just dictates what cycle the piston is on. So in one firing order number 3 could be on compression and on another firing order number 3 could be on exhaust.
Postmaster
Joined: Jun 2005
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Originally Posted by red89notch
mmmmm...
ok you do realize that the cam and crank both dictate the firring order? if the crank is right and the cam isnt no matter what order you fire the plugs in it's going to be screwwed. the crank and cam both have to be for the same firring order, if they are not the same i bet it wouldnt even run
the 351w HAS the same firring order as a HO 302, the regualar 302 has a different firring order
ok you do realize that the cam and crank both dictate the firring order? if the crank is right and the cam isnt no matter what order you fire the plugs in it's going to be screwwed. the crank and cam both have to be for the same firring order, if they are not the same i bet it wouldnt even run
the 351w HAS the same firring order as a HO 302, the regualar 302 has a different firring order
Nope... it's just the cam... you can run the same cam in any 260 289 302 5.0 or 351W ..... All they do is change the valve timing so what was TDC on the compression stroke is now TDC of the exaust stroke. Just like when you install the cam gears and you have #1 at TDC there is no compression or exhaust stroke it don't matter they are the same thing at this stage of the game.
just seen a few guys here have problems with new re-man 351W that had the older 302 firing order and they didn't now it.
