Hey everyone! I’m James. New to the forum, but have been doing bits of research on here for a while. I have a ‘74 factory v8 2 door. It was my dads project car, and I just recently got it running and driving in December. Dad passed away a little over a year ago. He was a ford parts guy since the early 70’s, and had tons of knowledge. All the lines and wires with markings were in ford part numbers, so that’s been an adventure. . The car has a rebuilt 302 and C4. I don’t know a bunch about what was done other than it was a pretty mild build, geared towards being a reliable daily. At one point we had a 73 sedan as a parts car, so I’m not sure if the motor and trans. are from that car, or a mix of the two. What I do know: Hypereutectic pistons, and I think dad had the engine balanced, and probably bored a little over. I remember dad saying the cam was mild, not Quite an RV cam. Ford racing manifold, and edelbrock 1406. Pulls about 16 inches mercury at idle, which I have set to about 800 rpm, otherwise it’s not very smooth. ( I’m at sea level if that matters) but I can get it to idle lower. It’s running a duraspark ignition, with an old NAPA brain box. It’s got a decent coil and wires. New gas tank! I had someone do that for me, the old one was Full of some BAD stuff. Rear end according to the door panel sticker is a 3, so I think that’s 2.79, which explains why it’s not impressive off the line, but cruises 70 at about 2000 rpm’s. Timing is a little over 10 degrees at current, provided it’s marked correctly ( somehow he had the firing order totally wrong, so I’m double checking everything I can. ) CVF pulley system, 1 wire alt. And Saginaw PS pump. Lokar throttle and kick down cables ( but I’m not convinced the kickdown is working because it rarely downshifts even at WOT) Factory exhaust manifolds, to 3 inch h pipe exhaust. I have headers for it, but not sure if / when I will install ( or if they’re even correct) Front discs, which I just had gone thru. Car had factory AC removed, and I need to put a new heater core in. There are some vacuum questions I’m chasing. There’s a line that travels toward the transmission that’s capped, in addition to the one I’ve got hooked to manifold vacuum. I read that EGR cars had something like this, but I can’t find any good drawings, and I do have EGR on the car. Also the canisters / etc for the heater controls need to get re-plumbed. I’m learning quick! I used to wrench a lot when I was younger, but it’s been a long time since I had anything with v8 and a carb. It’s been a lot of fun slowly getting things finished. My sons enjoy going for rides, and I’m starting to really enjoy a hobby I took a 15 year break from. Sorry for the long post!
"There’s a line that travels toward the transmission that’s capped." if the modulator vac line isn't hooked up that could be a shift problem...JMO
Welcome. If vacuum line to transmission modulator valve is disconnected/capped a C4 will not upshift(at least before 5000 RPM). Kick down is 95% controlled by cable. If modulator valve is adj for late upshift, a quick blip of throttle below 35/40mph will usually produce a 3rd to 2nd shift. Line that's blocked is probably vent from gas tank to charcoal canister. Only 16" vac at 800 RPM isn't great, if you don't have leaks, cam is likely a little more than a RV grind. Single plane intake will give sluggish performance at low speed, especially with stock converter & 3.00 gear. Disconnect vacuum advance and plug, total time engine for 35* at 3500 RPM. Unless initial setting is over 16*, don't worry about base timing, should give more vacuum & better throttle response. What's the firing order, 13726548 or 15426378?
And, that other tube being for the charcoal canister makes perfect sense based on its location on the far passenger side of the firewall.
Yup, that's the tank vent line... It really should remain open, assuming the gas cap seals properly, as fuel decreases a vacuum is created in tank. Sometimes collapses tank or at least prevents pump from drawing fuel. If you would like to know if engine is orig, look at stamp on top of block behind intake. First digit will be year of car, last six should match consecutive unit number of VIN(also last six).
Tom- That being the tank vent makes total sense. I fueled up the other day and was amazed how much vacuum there was in the tank. I just thought new cap, new tank, funky weather. Now it’s clear what was happening. Should I put a charcoal canister back in to the car? Also, It’s a brand new tank, so if I can keep it from sucking in gunk that would be awesome!
The charcoal canister is a good device. Vapors collected are routed to air cleaner to be pulled into carb & burned. Connecting hose was 1" or so paper/foil flexible line(I dunno if those are available). Basically relied on a slight negative pressure(vacuum) to draw vapor from canister. With most of us ditching the factory air cleaner, many decided tossing the canister was also a good idea. Above said, the canister wasn't among parts included with my car, line is open. I do now have one but needs a good detailing before install. My Fairlanes are pre charcoal canister. Vent line extends from tank, across back panel, loops over tail light assembly. Finally exits through floor into frame rail where it is open. Around three years ago one on Cobra plugged, big ole Carter fuel pump sucked the rubber seal out of gas cap. Began dumping fuel out filler on acceleration. Line clogged at 90* bend where it transitioned over tail lamp. Never really found anything and it laughed at a blast from air hose. A little gouging with core from a old speedometer cable cleared problem.
Thanks for the info, guys! I made some more adjustments, and got the car running better. Got the timing set to a little over 10 initial, apparently there’s a before and after TDC on the balancer Now this bad boy jumps from the stop light! Now I’m really noticing a surge on idle though. I sprayed some carb cleaner around the carb, and no issue, so I’m not thinking it’s a vacuum leak from that area. I think I might start all over with the idle adjustment on the carb. Could be a spark issue also, so I might chase that a little further, as it seems to miss occasionally at speed. Ugh. It seems like It’s running rich, or maybe one hole isn’t firing consistently. Good times! But, I jumped it from a