360 Rebuild for 1974 Swinger

-
furrystump said:
So you are going to prelube this with a drill to make sure you have oil to both heads and to see that it has oil pressure. I would mark each pushrod with a sharpie. Then as you prelube it and turn it over by hand, I would want to see that each pushrod is turning. I would usually do this before the intake was on and make sure each lifter is rotating as you turn it over by hand. If not I find out why the lifter isn’t spinning. A little late to the party, but if they don’t spin I don’t run it. You can probably look through the head and see if the lifter is rotating.
Click to expand...
Yes, I have the tool already to pre-lube the engine. Very important, I agree, though I'm not sure about turning it over. Won't that wipe off all the cam lube before it fires up the first time?
 
Making sure they spin is so much more important than the lube on the lobe. They die because the don’t spin.
 
Well, wish us luck. She's ready for first start. Oil pump primed, both upper ends got oil, sitting at 40psi with the drill running at full speed. Timing set to 12 degrees to start with, battery charged, fresh gas in the carbs, the tank has the gas from September in it but I stabilized it so it should be ok to use for break-in. Coolant all topped up, belts tight, all bolts checked and double-checked. I think we are ready.
 
Bl1zzard said:
Well, wish us luck. She's ready for first start. Oil pump primed, both upper ends got oil, sitting at 40psi with the drill running at full speed. Timing set to 12 degrees to start with, battery charged, fresh gas in the carbs, the tank has the gas from September in it but I stabilized it so it should be ok to use for break-in. Coolant all topped up, belts tight, all bolts checked and double-checked. I think we are ready.
Click to expand...
Fingers crossed good luck, RJ
 
No go. Lots of backfiring out the intake including a big one out the exhaust that sounded like a canon. I'm thinking after reading other forums that it might be a 180 degree dizzy problem. I sure hope so, because I don't relish pulling everything off the front end to check my timing chain. So tomorrow, I'll crank and check for pressure on #1 to be sure I'm on the compression stroke and see where the distributor is pointing. One thing I know for sure, I have fuel and spark and compression, gotta be timing.
 


It's running! Thanks to all FABO for helping. JustMoparJoe for all the tips on building a 360 on his YouTube channel. After break-in, took her for a spin before the next snowstorm is supposed to hit. Still gotta set the timing, tune the carb, flush the coolant, and bleed the brakes.
 
DJC said:
Yeah, I did the same thing. I'm sure my cam is a sh%^tty choice, I'm still running my ORIGINAL 7.25 rear end and stock converter that came with the used engine/trans from a 1973 motorhome. Oh, and a lousy Torker intake too. I bought what I could get my hands on because 1) parts are expensive, 2) parts are harder to get in Canada, and 3) parts are even MORE expensive in Canada.

But every time I go for a drive, I'm happy and I get lotsa nods. So build what you want.
Click to expand...
There’s nothing lousy about a Torker
In a shootout the torker was the best
For street
 
Bl1zzard said:


It's running! Thanks to all FABO for helping. JustMoparJoe for all the tips on building a 360 on his YouTube channel. After break-in, took her for a spin before the next snowstorm is supposed to hit. Still gotta set the timing, tune the carb, flush the coolant, and bleed the brakes.
Click to expand...


Congratulations... Freaking awesome!

I like JustMoparJoe, but his audio is lacking. Lol
 
Been tuning it up and fixing leaks, etc. Went for a couple of boots down the back roads, nothing over 55mph or 3000RPM lots of RPM changes.

I've never had a Holley 750 DP to tune before, but it seems weird. It has 4 idle mixture screws. Best idle with maximum vacuum has the front 2 screws turned almost all the way in, maybe a 1/16th of a turn out. The back 2 screws are ~1 turn each. Seems a little counterintuitive, but that where the idle is highest and vacuum is 15 and steady.

Question about timing. Running real nicely @ 15 degrees initial and 32 degrees all in @ 2800 RPM. Is there any recommendations based on the cam? It's a mild performance cam. Specs are below;

Cam Type Hydraulic
Exhaust Duration 224 Deg
Exhaust Lift (Inches) .310 in.
Exhaust Valve Lift 1 (Inches) .465 in.
Intake Duration 214 Deg
Intake Lift (Inches) .295 in.
Intake Valve Lift 1 (Inches) .443 in.
Lobe Centerline (Exhaust) 117 Deg
Lobe Centerline (Intake) 107 Deg
Lope Separation 112 Deg
Overlap 61 Deg
 
Congrats, I finally got mine going last weekend. It's a huge weight off your shoulders hearing it run again, and definitely gives you that boost to keep going!
 
Bl1zzard said:
Been tuning it up and fixing leaks, etc. Went for a couple of boots down the back roads, nothing over 55mph or 3000RPM lots of RPM changes.

I've never had a Holley 750 DP to tune before, but it seems weird. It has 4 idle mixture screws. Best idle with maximum vacuum has the front 2 screws turned almost all the way in, maybe a 1/16th of a turn out. The back 2 screws are ~1 turn each. Seems a little counterintuitive, but that where the idle is highest and vacuum is 15 and steady....
Click to expand...

That doesn't sound right. I'm no carb expert, and never had a double pumper either, but you're basically idling on the secondary circuits, which sounds like you have an internal leak or something out of whack. Was it rebuilt, or is it new, or...? You should be able to get them somewhat balanced.

Check this:

"If your car or truck has a camshaft with considerable duration (and as a result, a very lumpy idle), adjusting the idle mixture screws may not help very much. There’s an easy fix: adjust the secondary throttle stop screw. Holley four barrels like this 750 cfm 0-3310C have a small set screw located beside the passenger side throttle bore shaft bore (on the base plate of the carburetor, so you’ll have to flip it over). By turning the screw clockwise approximately 1-1/2 turns, the throttle blade on the secondary will open slightly. This allows a rather large amount of airflow through the carburetor without increasing the “window” seen by the idle transfer slot. At this time, the primary throttle blades can be closed, which tends to enhance the sensitivity of the idle mixture control."

from Quick Tech: How to Properly Set up the Idle on Holley Carburetors - OnAllCylinders
 
Last edited:
Also how much are the primary throttle blades open. It could be pulling fuel from the transition slot. That seems pretty far in to me. You could try and set it at the base setting and start backing out on the idle speed screw. Which would cover more of the transition slot=less fuel. See what that does to idle vacuum/quality.
 
IIRC The idle mixture screws add fuel throughout the engines entire operating range, however the transition slot only adds fuel during the transition. So you might be able to get the idle the same with little idle mixture fuel and more transition slot or more idle mixture fuel and less slot. But those two situations result in differences off idle.
 
Brooks James said:
There’s nothing lousy about a Torker
In a shootout the torker was the best
For street
Click to expand...

Not sure where you get your info, but the Torker would be at the bottom of the list for best street intake.
Its a dinosaur. There is much better choices out there for the street and the track. I would use it for a door stop, if I had one. Back to our regularly scheduled broadcast.
 
DJC said:
That doesn't sound right. I'm no carb expert, and never had a double pumper either, but you're basically idling on the secondary circuits, which sounds like you have an internal leak or something out of whack. Was it rebuilt, or is it new, or...? You should be able to get them somewhat balanced.

Check this:

"If your car or truck has a camshaft with considerable duration (and as a result, a very lumpy idle), adjusting the idle mixture screws may not help very much. There’s an easy fix: adjust the secondary throttle stop screw. Holley four barrels like this 750 cfm 0-3310C have a small set screw located beside the passenger side throttle bore shaft bore (on the base plate of the carburetor, so you’ll have to flip it over). By turning the screw clockwise approximately 1-1/2 turns, the throttle blade on the secondary will open slightly. This allows a rather large amount of airflow through the carburetor without increasing the “window” seen by the idle transfer slot. At this time, the primary throttle blades can be closed, which tends to enhance the sensitivity of the idle mixture control."

from Quick Tech: How to Properly Set up the Idle on Holley Carburetors - OnAllCylinders
Click to expand...


Thanks for this. I took the time and reset all the screws back to 1 turn out from fully closed. Hooked up the vacuum gauge and warmed it up, set idle to 750RPM, timing 15 degrees at that idle speed. Then I slowly turned each screw a little bit at a time for best vacuum. They are all now ~half turn out from fully closed, vacuum is solid at 15 ??? (whatever the measurement is) and idle is steady at 750 RPM and timing is still 15 degrees. I think she's dialed in. As a matter of fact she squeaked the tires at the lights with just a little too much gas pedal, so I know she's happy with that configuration.

Now, on the the ever growing list of things I want to do. Replace seatbelts, find sail panels, track down missing interior screws, get a nice stereo, replace the wheels and tires, you know, it never ends.
 
You must log in or register to reply here.
-

Back
Top