Need holley help...

[John Smith]

It's been neat to listen in on your discussion..

The carb stuff definatley takes a guy way back...
I remember working on my "55" Ford..16 at the time...fuel injection u only read about...I happen to have a cple duraspark dizzys from the 70's..i just can't throw them away...i still have motors they fit..

chances of me making it over there are pretty slim......i've never been east of alberta in my life.

but once it warms up i'll be happy to walk you through the process.

while there's always been some confusion over vac source for advance,i think it's even worse now as it hasn't been used in 25 years(which also makes finding good stuff at the wreckers near impossible-it's all 25+ years old too)so most mechanics aren't familliar with it unless they're old farts like me.

all this computer gobeldeygook is great for making engines run nice,but there's a certain satisfaction dealing with stuff where you can actually see what's doing what.

 

[The_Dealer]

yea definately happy with how its running. about to swap in an fm146, do a top end refresh with p&p'd heads and port matched I/M and all new gaskets. gonna use some 2.9 valves with the heads machined for them to fit, and a cam, edelbrock headers, and thats about it. not trying to get major power i just figured while im in there getting rid of some lifter tick i might as well throw a few things on it. gonna be 100,000x better when i get the fm146.

 

[kimcrwbr1]

I think where the main problem is those older dampers due to time and pressure lie. I know with HEI ignitons on a 302 your best to time it with total advance I believe it is 38 degrees at around 2500 rpm or until it pings and back off a little. The thing with the 2.8 you cant hear the ping and I am posative those 28 yrs old harmonic balancers are not giving you proper tdc. I have tried every way imaginable to get ported vacuum to work correct on my 2.8 but I get the best performance using manifold vacuum. The last time I adjusted the timing and idle air, first I hooked up a vacuum guage and set the timing at 10 dbtdc and adjusted the idle air for the highest vacuum 18hg and then retarded the timing until I got 16hg in vacuum. The timing according to the damper is at 15 dbtdc with the vacuun advance plugged into manifold vacuum. with zero hesitation at any throttle position and was able to pull tiger mountain pass at 60+ mph for the first time since I got the truck. With the advance hooked up to ported vacuum You have to open the butterflys up to get it to idle proper right at the point it advances it giving a real erratic idle. At least that is how mine runs best 15dbtc and the idle jets about 3 turns out I am sure it has everything to do with the damper and total timing. The advance only counts for 10 degrees so at higher rpms with the throttle plates so far open ported or manifold are virtually the same it is in the lower end you need to retard the timing for torque and idles alot better when it is advanced. At around 2500 rpm my total advance is about 42 dbtdc at 20hg in vacuum. I am just guessing here but actual total advance is around 46-47 btdc. Does anyone here know where I can get a new harmonic balancer for A 2.8. I have to prove my theory and the only way to do it would be with a new oem part. I dont trust a reconditioned ones for accuracy

 

[gwaii]

I think where the main problem is those older dampers due to time and pressure lie. I know with HEI ignitons on a 302 your best to time it with total advance I believe it is 38 degrees at around 2500 rpm or until it pings and back off a little. The thing with the 2.8 you cant hear the ping and I am posative those 28 yrs old harmonic balancers are not giving you proper tdc. I have tried every way imaginable to get ported vacuum to work correct on my 2.8 but I get the best performance using manifold vacuum. The last time I adjusted the timing and idle air, first I hooked up a vacuum guage and set the timing at 10 dbtdc and adjusted the idle air for the highest vacuum 18hg and then retarded the timing until I got 16hg in vacuum. The timing according to the damper is at 15 dbtdc with the vacuun advance plugged into manifold vacuum. with zero hesitation at any throttle position and was able to pull tiger mountain pass at 60+ mph for the first time since I got the truck. With the advance hooked up to ported vacuum You have to open the butterflys up to get it to idle proper right at the point it advances it giving a real erratic idle. At least that is how mine runs best 15dbtc and the idle jets about 3 turns out I am sure it has everything to do with the damper and total timing. The advance only counts for 10 degrees so at higher rpms with the throttle plates so far open ported or manifold are virtually the same it is in the lower end you need to retard the timing for torque and idles alot better when it is advanced. At around 2500 rpm my total advance is about 42 dbtdc at 20hg in vacuum. I am just guessing here but actual total advance is around 46-47 btdc. Does anyone here know where I can get a new harmonic balancer for A 2.8. I have to prove my theory and the only way to do it would be with a new oem part. I dont trust a reconditioned ones for accuracy

ya,that's the thing about dealing with something that is that old,in your case 28 years.the way that the engineers designed the system to work may need to be tweaked to compensate for wear and other age related factors such as the balancer shift you mentioned.

as for the balancer,you can get around some of that issue by making a tdc mark on the pulley,which is bolted directly to the hub,and therefore keyed to the crank.this will at least take one variable out of the system,and give accurate timing for the engine.

from what has been described in this thread,it sounds like there is not enough advance dialed into the base timing,i wonder if the balancer could be responsible for that.

i kind of liken this to driving a fuel injected car with the cel on...it may seem to run fine,but you know something is wrong.in this case,there's no light,but having it work better with the advance hooked to manifold vacuum tells me something is wrong,whether it's general wear,or some misadjusted component.

 

[kimcrwbr1]

Sorry I meant MSD ignition not HEI

 

[kimcrwbr1]

I think the 2.8 is just a different animal all together the richer you adjust the idle air the better the gas mileage also you need a minumum of three turns out on the idle air needles. At least that is what I have found with the 2150 carbs right now I am running #46 jets with a 1,08 venturi. I keep threatening to switch to #50s and see if it makes a difference on the upper end but she`s running pretty good right now. That is another one of my theories that the idle jets supplement the mains until the butterflys are open far enough to pull fuel through the venturies. If you set the idle air too lean it will stumble every time I`m talking less than three turns out. Im sure age has alot to do with that also.

 

[Mutant Pony]

Gwaii is right, I've seen all kinds of engines with the vacuum advance hooked to manifold vacuum and I've always wondered why anyone would think that was right. I've amazed people by just connecting the vacuum right. Most times, someone has spent a lot of time adjusting timing and carb settings for the improper vacuum connection. Much of the Original posters problems sounds like timing to me. Just because a distributor is new doesn't mean much. As Gwaii said, make sure the Mechanical advance is actually advancing the timing as you bring up the RPMs.
I almost lost a truck to fire because of an improperly assembled "new" distributor. True story!
You can also "view" the vacuum advances function with a timing light, just to make sure it is functioning properly.

 

[The_Dealer]

checked it tonight 12* with vac unplugged. didnt get a chance to check it with advance hooked up on the carbs port. started raining on me. anyone know about the ford kickdown adjustment?

 

[gwaii]

anyone know about the ford kickdown adjustment?

my best suggestion is to tweak it till you're happy with it.if it's downshifting too soon,back off the screw.

 

[Mutant Pony]

Make sure the rod is allowing the lever on the trans to go all the way up, it may need to be bent a little. With the rod pushed all the way up, the carb should just hit it at full throttle.

 

[kimcrwbr1]

checked it tonight 12* with vac unplugged. didnt get a chance to check it with advance hooked up on the carbs port. started raining on me. anyone know about the ford kickdown adjustment?

I can tell you without looking with the vacuum unplugged you get 12 degrees then on ported you get 12 degrees there is no vacuum at an idle. How far is it advanced at 2500 rpm or total advance with everything hooked up.

 

[gwaii]

Make sure the rod is allowing the lever on the trans to go all the way up, it may need to be bent a little. With the rod pushed all the way up, the carb should just hit it at full throttle.

good point.....btw,cool car.i've always liked the pinto,right back to gapp&roush.

always thought it got a bad rapp.