440 HP cam shaft specs

[451Mopar]

When I work on AFB type carbs, one of the first things I check is the float/fuel level. It is a pain because you have to pull the top of the carb off (after running the fuel pump) to check how much fuel is in the bowls. I like to see fuel even with the notch in the separator plates in the bowls.

 

[junkpile]

o.k. I got around to do something on the car this weekend, not a lot but something.

I checked the floats in the carb, all is spot on. I did a smoke check to the intake, with a homemade smoke machine. I capped the vacuum line for the brake booster and put smoke in the vacuum tree on the intake where the headlight doors plug in. The only smoke that I could find came out around the rag I stuffed in the carb at the stud for the air cleaner. I could not find any smoke coming out anywhere else. I may have to try again and build more pressure to force the smoke out but I had that intake full of smoke and a lot came out after removing the rag from the top of the carb.

I still have not tried running a straight mechanical advance by disconnecting the vacuum line and setting the base timing to 13. Does anyone think it could be a fuel pump issue? I have no other issues except WOT from a stop then it bogs and sputters out in any gear. could the fuel pump not supply enough fuel on the low end but enough to keep it running fine everywhere else?
oh checked the PVC valve, and all vacuum lines nothing was bad.

 

[lewtot184]

a stock magnum cam is 213@.050", 121@.200", on the intake; 225@.050", 131@.200" on the exhaust. they are not 268/284 duration, and they are not the .050" numbers that mopar advertises. they're ground on a 115LSA with 2 degrees of advance.

the 750 carb has too much primary jetting. step down to .104 or .106. ditch the .043" squirter, for a .028". the 284 cam isn't ideal for an 8:1 compression engine. i'd take at least one step down in camshaft; two steps would be better.

 

[junkpile]

Just and FYI
althought I do not have the exact stats on my compression. the motor is .030 over with dome top pistons that are notch cut for valve clearance. I did not build the short block. I bought it from a guy who wrecked a 69 RR. I had a stock 69 440 that after a "professional" rebuild, shattered a cam shaft cruising to a show in April of 2000, I bought the short block and added my stock 440 heads and M1 intake. along with the new 484/284 cam. I am not sure on the compression ratio, but I know for a fact it ran great back then with no issues. the distributor was run with vacuum advance disconnected and the carb was a total gas dumper with all the choke and accessories stripped off of it. I changed to a Eddy 750 with electric choke its been gone thru to its best running, just this wot bog has been killing me. I need to fix this problem once and for all and not just limp the car thru the season.

 

[oldbee]

Move ur acc.pump linkage to outermost hope to lessen the pump shot a little & try it. Cheap&easy. F.pump can’t cause an instant bog, there’s no time for you to empty the float bowls.

 

[junkpile]

ok everyone here is the update.
1st I found my new distributor does not have an adjustable vacuum advance, that will come into play later.

After my smoke test show no leaks that I could find, I went back to basics and a new approach. I decided to time the engine using a vacuum gauge. I disconnected the vacuum advance hooked the gauge into manifold vacuum. after the car warmed up I got a reading of 7"vacuum. I slowly moved the distributor increasing the vacuum it maxed at 13", from there I backed it off 1.5" to account for any engine ping so that would leave the total at 11.5". Then I put a timing light on the car, it was reading 18btdc that was way above what I was told to do with the 484/284 cam but I said what the hell lets give it a try. I reconnect the vacuum advance, rest the idle and took it out.

Car ran normal nothing unusual. took the car to my "spot" to give it a real test, and my jaw dropped. The damn thing pulled hard no bog in drive at WOT. I did 4 tests all great, then did 2nd gear starts, lot more tire spin but no bog and then a flat out burnout and lift off the brake pedal full pull no bog. I have never been so happy with this car.

I do have some siginificant engine ping but I feel if I had an adjustable vacuum advance I could take care of that without changing the base timing which works and fixed the WOT bog.

 

[junkpile]

oh if anyone can make a suggestion on a good distributor to fit stock electronic ignition wiring I would be glad to here it so long as it has adjustable vacuum advance.

thanks and thanks for all the help

 

[HALIFAXHOPS]

I could prob set yours up any way you would want it.