Need holley help...

[The_Dealer]

well i change from #61 jets to #53 jets in my holley 350 cfm 2bbl, and im getting some off idle hesitation. not WOT, its fine. but when i take off easy it kinda hesitates then goes. also if im cruising in gear and let off and give it gas again it hesitates a little bit. any ideas on what it could be? brand new carb. about 1k miles on it. im 100% positive i did everything right when i changed the jets. its not rocket science and i didnt get any crud where it shouldnt be. ive never messed with idle mixture, and the float is just a hair under the sight(for offroad purposes). fuel filter brand new, timing ok

 

[doorgunner]

that's a BIG decrease in hole size...try increasing the jet to a # 55...if things improve, but there's still a little hesitation....go to a #57 jet...

being a machinist...I drilled #50jets out .002" at a time until the stumble wasn't noticeable....I ended up with modifed jets 5 sizes smaller that the jets that came installed in the carb....


and it'll still smoke the tires on take-off (350cu. in. 4-barrel)

 

[mn_smokeater]

that's a BIG decrease in hole size...try increasing the jet to a # 55...if things improve, but there's still a little hesitation....go to a #57 jet...

being a machinist...I drilled #50jets out .002" at a time until the stumble wasn't noticeable....I ended up with modifed jets 5 sizes smaller that the jets that came installed in the carb....


and it'll still smoke the tires on take-off (350cu. in. 4-barrel)

this.

when it comes to the stuff like this DG knows his stuff

 

[The_Dealer]

i was under the inpression that the stock holley jets were way to big for the 2.8. at least thats what my searching turned up. most are running #52-#55 jets. i was getting shitty gas mileage with the #61's. also my when cold it bogs like a bitch on take off. i have to keep feathering the gas to get it to go. the stock 2150 didnt do that. i never had a choke hooked on that carb and it was fine. this holley does not like cold starts

 

[mhughes165]

throw a vaccum gauge on it and tune the carb.....

 

[doorgunner]

this.

when it comes to the stuff like this DG knows his stuff

thanks.....but not really...I just try things until it works better------or is destroyed!

throw a vaccum gauge on it and tune the carb.....

I fergot about that--- vacuum gauge is a neccesity on a carb.....

 

[mhughes165]

thanks.....but not really...I just try things until it works better------or is destroyed!






I fergot about that--- vacuum gauge is a neccesity on a carb.....

its allright, well just write it off as old timers disorder

 

[Mark_88]

throw a vaccum gauge on it and tune the carb.....

I was just going to post this myself...if you have hesitation there is a possible vac leak...

 

[The_Dealer]

pretty sure its not a vac leak. im durasparkd so the only vac lines i have is pcv, brake, trans and disty. btw im getting mixed opinions on where to put the disty line, some say manifold tee...others and holley instructions say ported vac on the carb...i need a straight answer

 

[Psychopete]

pretty sure its not a vac leak. im durasparkd so the only vac lines i have is pcv, brake, trans and disty. btw im getting mixed opinions on where to put the disty line, some say manifold tee...others and holley instructions say ported vac on the carb...i need a straight answer

Follow Holley's insrt. Don't want it hooked up to manifold vacuum. +1 on vacuum gauge. I would recommend reading through a good book on the carb itself.

 

[TwoWhels]

I think you need to make an adjustment to your accelerator pump.
Try increasing the amount of fuel it puts out.

 

[Mark_88]

I would have to suggest the manifold on the distributor vac...I tried mine on the original carb on a lower connection that was part of the emission setup and it didn't give me the advance on the timing needed...but if you've got a T or some other arrangement that is off the manifold that would work too...

As for vac leak...I found my 5200 was not sealed properly at the base of the carb...so it was a vac leak, but not from any vac lines...it made a huge difference...are your brakes OK? That might give you an idea if it is a vac leak or not...the booster looses power...mine was and I thought I had a leak (which I did, incidentally)...

Otherwise...could just be the carb itself and in that case I'm not familiar enough to advise...

 

[The_Dealer]

carbs brand new, i used the fel pro gasket everyone said to get, carb bolts are tight, i dont think that its a base leak, brakes and everything works fine...maybe a bad pcv valve? im kinda scared to start messing around not really knowing what im doing

 

[gwaii]

distributer needs to be hooked to the venturi vacuum port on the carb.

the manifold vacuum decreases when the throttle is openned,and this is exactly when the advance is needed.the venturi vacuum increases when the throttle is openned,pulling more advance onto the distributer.

 

[The_Dealer]

I would have to suggest the manifold on the distributor vac...I tried mine on the original carb on a lower connection that was part of the emission setup and it didn't give me the advance on the timing needed...but if you've got a T or some other arrangement that is off the manifold that would work too...

As for vac leak...I found my 5200 was not sealed properly at the base of the carb...so it was a vac leak, but not from any vac lines...it made a huge difference...are your brakes OK? That might give you an idea if it is a vac leak or not...the booster looses power...mine was and I thought I had a leak (which I did, incidentally)...

Otherwise...could just be the carb itself and in that case I'm not familiar enough to advise...

the vac nipple that holley recommends is actually a ported vacuum just for distys