New Carb

[78F250]

I really need a new carb for this truck. It sticks in high rev. All I was doing was backing it in the driveway and it was kicking at leat 50000 rpms. I wasn't touching the pedal at all. What CFM carb would work best on a strong 400 engine?

 

[DNFXDLI]

Sounds like a sticking linkage perhaps.
No bigger than a 650...with a 600 Vac secondary being your best bet.

 

[UNRULEE]

I went with a Holley 670 Truck Avenger due to the off camber abilities of it. No complaints since it went on a few years back.

 

[LEB Ben]

Sounds like a sticking linkage perhaps.
No bigger than a 650...with a 600 Vac secondary being your best bet.

That gets my vote. I prefer Holley's and the 4150 series for street friendliness and ultimate tunability.

 

[78F250]

So I would be strangling the motor if I went with a two barrell?

 

[DNFXDLI]

So I would be strangling the motor if I went with a two barrell?

Not necessarily..but a 500 cfm 2bbl would have 2 fairly good sized bores and you would see better overall performance and efficiency with a 4 bbl with smaller bores...you would create better over vacuum and a/f atomization.

 

[cipsmithers]

and it was kicking at leat 50000 rpms.?

now thats my kind of rpms. built ford tough!!!!!!

 

[78F250]

Yeah, I tried to edit but the button wasn't there.

 

[rickpilgrim]

On my 'scapers 77 F250 4x4 with 400 c-6 we added cam, headers, accell ign and a weiand intake with a Holley 0-80457S 600 cfm carb and he says its way way better in performance and economy.

 

[73F100Shortbed]

Wow are you sure someone didn't put Toyota parts on there?

Seriously though I would have to agree with sticky linkage.

 

[gsxr1238]

X2 on the linkage and the 600cfm replacement.

 

[78F250]

Wow are you sure someone didn't put Toyota parts on there?

Seriously though I would have to agree with sticky linkage.

Well, once the carb is replaced, the sticking problem should be ok.

 

[Jolly Green]

You sure it isn't a choke issue? Maybe just out of adjustment and sticking on fast idle? Are you up to operating temp when this happens?

 

[Truckin4life]

i won ftf with this post...
Lame post pad, but i win.

 

[78F250]

It wasn't to operating temperature. I was just backing from the street into my driveway. I thought the electric choke would take care of that.

 

[LEB Ben]

It wasn't to operating temperature. I was just backing from the street into my driveway. I thought the electric choke would take care of that.

How many times has this happened? Was it just that one time? Have you lubed down the linkage so it can move freely and eliminate that as a problem.

i won ftf with this post...
Lame post pad, but i win.

What the eff are you talking about?

 

[Jolly Green]

It wasn't to operating temperature. I was just backing from the street into my driveway. I thought the electric choke would take care of that.

The electric choke will automatically set to curb idle when the truck is warmed up (once you hit the gas)--until then it will want to stay on fast idle. There are two settings on the cam. Hit the gas once knocks it down to lower rpms--hit it a second time to drop to curb idle. It won't drop until it's warm though.

 

[Jotun]

I am partial to 600cfm Carter AFBs they are much easier to work on that Holleys IMO. My motto "Keep it simple Stupid"

 

[1985 Ford F-150]

I hate electric chokes. I disconntected the linkage on my edelbrock and twisted the plastic cap till the choke butterfly opened up all the way. Never had a cold start problem just gotta pump it a couple times and then rev it to 1000 for a little bit till it warms up then its fine.

 

[cipsmithers]

I hate electric chokes. I disconntected the linkage on my edelbrock and twisted the plastic cap till the choke butterfly opened up all the way. Never had a cold start problem just gotta pump it a couple times and then rev it to 1000 for a little bit till it warms up then its fine.

i had an electric choke on the old motor in the blue ford. i hated it. i could never get it to work. when i would go outside in the morning, i would pump it a couple times, start it, it would try to work, then die, repeat process, it would fire, and hold at 2000 rpms till i kicked it down. never could get it to work. new motor has manual choke. lots better. dont even need it this time of year, but did use it this winter