|05-20-2002 03:05 PM|
Well, after trying all the suggestions I got from everyone, I figured out my problem.
The timing set was aligned wrong, I was looking at the zero on the crank sprocket as the alignment circle. It was not the right cicle, the actual circle was offset by 3 or 4 teeth. Aligned it correctly and now this baby runs great!
Thanks for all the input.
|05-17-2002 05:37 PM|
Man, I'm totally stumped.
My floats are fine, pressure isn't too high, just over 5 lbs. I even took the carb off my ford, it's also a edelbrock electric choke #1406, and it does the same exact thing. The thing is dead and gargles gas.
The distributor is working right, I put the heavy springs on and then the light springs and didn't make much difference.
I talked to the edelbrock tech and he was going to fax me the timing set specs( diagram ), to make sure I lined up properly, but never heard from them. Figures!
Anybody got the timing alignment for the edl-7800 timing set? The keyway is different from the OEM sprocket, the keyway is lined up directly with th e circle mark. The OEM sprocket is a few degrees from the circle on the sprocket. They say this is so the cam will rum "straight up".
|05-16-2002 01:25 AM|
well the basics of ignition timeing the way i see it is there is three types of ignition timeing (i'm only familair with points type ignition tho),1st is initial timeing thats the one you set with timeing light ..lets say 10* advance at idle with vacuum hose from dizy disconnected. 2nd is machanical advance and that is likely to be a set of machanical weights under your points plate or rotor inside the dizy, and as the engine spins them faster the centrifical forces make them open out which advances the points plate or rotor, lets say about another 26* at around 2800 engine rpm. 3rd type is vacuum advance which is normally connected from dizy to manifold vacuum and its the vaccum that pulls on the points plate to advance it,lets say the vaccum advances it another 4*. lets add this all up and we get 10*+26*+4*=40* of total advance but since there is bugger all vacuum when you stamp on the gas you can forget the 4* and make it 36* total.this is why its important to disconnect the vacuum hose when you do your initial 10* timeing because there is alot of vacuum at idle and that gives ya a false reading .some ppl have there vacuum advance connected to ported vacuum on the carb so it is pulling a vacuum when the gas is on and probably have less machanical advance to compensate.....confused ?...me too maybe someone else can explain it a bit better . this setup works really good for my 350 tho.
of course this has nothing to do with cam timeing which is a diferent fish altogether ...
|05-15-2002 04:07 PM|
Well...thanks for the suggestions everyone, I will try them and see what happens (or doesn't).
I'm going to remove the timing cover, again, and double check that, I know its lined up right, but will do this to be absolutely sure.
Another question, I'm getting a lot of input about the mechanical timing, advance timing, what is the difference and what is the best way to set mechanical timing. Most people I speak too, say 36 degrees at 2500 RPM or so, is this advance or retard....(or am I not advanced).
|05-15-2002 08:04 AM|
|middspecauto||change your timing to ten degrees b.t.d.c. and turn your carb adjusting screws in until it barely runs by itself(chugging and popping) and then turn them out by one fourths until it smooths out. take it for a test drive and just move the distributor a couple degrees at a time until it starts losing power again and then set it back to your last setting. seen this problem a million times. when you change one variable they are all affected. try it, what do you have to lose?|
|05-15-2002 03:06 AM|
|HQ Pete||hello furfman, when you changed the cam are you absolutely positively double triple sure that you got the CAM timeing right and not a tooth out ?sounds like it may be a bit retarded.you can quadroople check it by "degreeing" the cam if you have the cam spec's.since it is a new cam you will have new lifters i hope. i would take the valve covers off and start her up and make sure the pushrods are rotateing ,i like to mark them with a white pen so its easy to see them rotateing,if there not rotateing it could mean the lifters are'nt rotateing (bad if hydralic flat tapet cam)also double check your valve ajustment. pull the plugs and inspect them they sometimes are a good indication of problems.your cam seems of average lift/duration and i run the same cam with a 600 holly with no problems i had to rejet it cause it was poping and farting up top from being to lean tho.these are a couple of possible answers but it could be something else totally unrelated.hopefully its something simple like a kid put a bannana up the tail pipe or something ,good luck and keep us posted|
|05-15-2002 02:48 AM|
|roys63||You my have a fuel pressure problem or low floats in carb.|
|05-15-2002 02:34 AM|
Thanks for the reply, I changed my metering to step 23 in my manual, per edelbrock tech support, but didn't change anything.
I said in my first post that the motor lacks power, I mean gutless, it was a rod, now it's a go-cart, can't accelerate or even make it up a hill. If I give it any more than 1/3 throttle under load, it would bog out real bad. I wonder if the timing set is wrong, I got the edelbrock set reccomended for the cam and such.
I have the exact same setup in my 351m, and never had any problems like this.
|05-14-2002 05:34 PM|
|Steve karch||I kind of had the same problem with my motor after I rebuilt it. I have a 355 sbc with a 214-224 cam, weiand stealth intake, headers etc. I played around with the carb and timing. With the carb (same as yours) I changed the step up springs to the stiffer ones (or it could be lighter, cant remember). Basically the metering rods open quicker on full throttle. This cured a big hesitation when the throttle was floored. I went to the next bigger jet and the next smaller metering rod. Bigger cam and intake equals more fuel required. I set the accelerator pump rod to the top setting. This made a major difference in performance. As far as the timing goes, I thought I had it set good at 12 deg but I advanced to to 18 degrees at idle and 32 degrees mechanical at 2600 rpm . The mechanical advance is still a little low but thats as far as my distributor will go. Its a Hei. The power is strong on the low end and pulls hard to 5500 rpm. I also installed a MDS ign module. I think your problem is more tune related and it just take some fiddling to get it right. Also make sure there are no vacuum leaks.|
|05-14-2002 04:30 PM|
My 350 Chokes!
I'm writing in search of possible answers to a problem I have with a camshaft change.
I have a 1975 350 4 bolt I rebuilt 2 years ago, I have a 600 cfm edelbrock carb, performer intake, 214 degree duration camshaft with about .450 lift on each valve.
I have this terrible lack of power, I mean it gargles when I get on the throttle and just stumbles over itself.
I am at wits end trying to figure this problem out, I have replaced the plugs, wires, cap, and rotor, the distributor is in and timed correctly, the engine timing is close to perfect, but I still haven't any power at all.
I have a nearly new Pertronics coil and module that I have been using. All worked very well until I did this cam swap.
If you can provide me with some suggestions, I would be grateful.