I've talked quite a bit with orich so if you're out there - i've got this on going issue with my 70 F250 - 360 Edelbrock Performer aluminum manifold,Motorcraft rebuilt 600 carb,headers,MSD disto & 6A box,new Taylor wires, 2 different sets of new plugs - some platinum Autolites and some NGK'S with some new "v" technology crap that only the japs know what they're going to do - new gas tank,fresh 89 gas with Lucas cylinder lube,all new lines,new fuel pump and filters - when i set the new disto in or more how i'm going about it now is to turn the engine over by hand to TDC # 1 with the valve cover off to be sure both valves are closed - holding the body of the disto with the notches for the cap clips as parallel with the front of the truck as possible setting it into the hole putting the cap on and using a screwdriver as a straight edge thru the coil wire thru # 1 and marking that spot on the valve cover for reference and trying to drop the disto down with the rotor pointing towards that mark - the disto does one of 3 things either it does'nt go down at all,it goes down but does'nt seem to seat and i'm assuming this is not engaged with the oil pump shaft,or it seats completely now this is how it acts thru many trial and error sessions.I had originally made my first mark just thru eyeballing without using a straight edge and this was my first mark.I can't get the disto to drop all the down using my 2nd mark which to me would be right on - it goes all the way down with the locale of the first mark - in using that mark lighting the engine off it barely idles and backfires out of the carb if i advance it using a timing light it smooths out at around what seems to be 12 btdc and idles great - give 1/3 - 1/2 throttle and it backfires and pops out of the exhaustn alot - i've gone thru numerous sessions of trying to retime it and this seems to be the best it gets any ideas? compression is good 145 in 5,140 in 2 & 135 in 1 thats not a wet test only dry - I don't want to get into changing a timing chain unless i'm sure thats the problem -

 

Which msd dizzy do you have, did you replace any of the advance springs or bushings. I would not worry much about making marks and trying to get them to line up.

If the motor is on TDC stab the dizzy, which ever post the rotor is pointing at is your number one and wire the cap accordingly.

We need to know which springs and bushing you have in the dizzy to help set a base timing, but 18 BTDC is pretty close. One thing to look at is if the wires coming from the MSD box are switched going to the Dizzy. (green and purple I believe) Motor will run if switched but not good, I had them switched on my 7 box and the car backfired a lot at idle, switched the fires and it cleared right up.

 

You'll have to most likely turn the engine over to correctly set the dizzy.

 

Disto is the 8594 which is what MSD calls for for FE big blocks apparently from the 360 all the way to the 428 - everything is as it came outa the box so the stock setup from the factory i'll go back thru the literature as i know i saw it somewhere as for wiring its according to their diagrams - but its something i can check.Power for the box comes off the battery so pertaining to switching i'd imagine its got to go thru the ignition switch otherwise it'd be hot all the time I'm using a regular igntion coil actually a Pertronix Flamethrower so its what 44k off the secondary windings i believe - i did'nt get bit with that side but tapped the primary side which is only 12 dc but i still felt it - 44? YIPES - So you've had similar problems?

 

I see in regards to green & purple you meant swapped around i'll check if i get home in time tomorrow from work -

 

I turn it over every time to TDC # 1 by hand -

 

Nor should you re-enact scenes from Platoon with Charlie Sheen or for that matter have anything else to do with him -

 

springs are the heaviest - silver - bushings are the blue ones -

 

Msd makes a few dizzy's for the fe just wanted to make shure what it was.

If it were me I would throw the heavy springs away, but they are the safest to tune.
If you set initial timing at 15 btdc at 2000 rpm you will have 28 degrees of total timing at 4000 rpm.

 

As far as just getting the oil pump shaft to line up where you want it, you can turn it by itself with a 1/4" drive socket of right size taped to an extention. May take a couple tries to get in exactly right for distributor to drop in where you want it.

 

Being you why would you throw the springs away? quicker wind-up but then you may also have a tendency to ping? Now the blue bushing limits total advance - its going to be very close to 15 as it sits so i've obviously got something else going on - You can't swap the green and purple they fit into a quick release connector just 1 way and actually change color there to a black with an orange stripe and a black with a purple stripe - I'm all ears hows about some more things to go on sooner or later we'll hit it.Right nows not that big of a deal as i've got to get rims and tires for it - its got some slop in the steering and hopefuly i can adjust it out at the steering box - then i have to somewhere along in here get tires and some new steering brakes for the buggy - but when the 2 start coming together -

 

I myself would toss the springs because you got to put so much initial advance in the motor to get the total advance you want. In your case total advance of 28 will rarely ever be seen. how often do you think you will make pulls past 4000 rpm. also a lighter spring and smaller bushing will allow for a lot less initial timing which is easier on starters with higher compression motors. Really its just a tuning issue it should run fine the way you have it.

The wires going from the msd box to the dizzy should be right if you are using msd p/n 8860. I would make sure that the solid purple wire matches up with the orange/black wire on the dizzy and the green wire matches up with the purple/black wire on the dizzy.

If that all checks out make sure the firing order is correct, 1-5-4-2-6-3-7-8 and the rotor turns counter clock wise. I know its trivial but, I see it get messed up all the time, did you number the cylinders correctly. 1-2-3-4 passenger side and 5-6-7-8 drivers side.

even know the carb is rebuilt are the floats set too high, this could cause excess fuel to overflow into the motor causing raw fuel to possibly be dumped into the exhaust causing a backfire.

If this is a new build I would pull both valve covers and see if any rockers are loose, I have seen cams go flat and cause back firing issues wile going down the road but idle like a top. If its a new build hopefully you used a zink additive on the initial brake in of the motor, If not very possibly the cam has gone flat.

 

First off no its not a new build i'm postive the engines never been apart - i'd be willing to bet its all original.At least they must've changed the oil and filter fairly regularly as there was very little sludge in the valve train.With a lighter spring you'd get your advance in quicker hence more punch which is fine as long as i can do it with no knocking/pinging,and not having to run Premo. Now the smaller bushing would actually allow more advance which i'm not sure would necessarily be all that good with a relatively stock motor.I will check how those wires match up tomorrow when i can see my hand in front of my face i know thats why God created flashlights if it were the weekend sure - Tues? naw, i'm planted.It could conceivably be a flat cam lobe - in one of my investigative sessions i'd actually popped one of the lifters out and i was amazed the damn thing looked brand new - not any sign of wear no pitting no slight indentation where the lobe was running - nothing and clean nice and shiny - It could also be a worn chain and gears but you'd see a fluctuation with the mark on the damper would you not? Or if it was just slight enough to cause it to do what its doing but not enough to show up that way? - thats why i'm talking to you guys as you've got that ton of experience.The carb i'm not sure i did'nt do it and am not set up to properly rebuild carbs at this time.I don't notice what seems to be an adverse amount of gas - any stains on the side of the bowl or anything gaskets get moist but thats normal.Now the plugs thats a real sticker some will look right-on a nice chocolate brown on the porcelain with a dark grey outer ring on the plug ring - and some will look soaked almost fouled like they had'nt been firing at all - and its random it does'nt follow any order like all on one side or the other some on one some on the other.I will go back and check the wires yes # 1 the first plug to the front on the pass side increasing as you go back 2,3,4 - #5 first all the way forward on the drivers side i'll check again i know sometimes its the most obvious things.Guy who did the carb thats all he does is fuel systems and diagnostic tune-ups.I've never registered the truck in my name yet i've had it probably 8 months and its been an ongoing pile of work had ALOT of surface rust which has been a bitch but i think i've got it under control and fiddling with the engine.This is my first foray into really working on my own v-8 as i've owned mostly small sporty cars or hot rod air cooled VW's so its a real learning curve where i'll get pissed off and walk away from it for a week or so - don't do that anymore as its starting to come together - So i can't take it down to him and say WTF is it the carb? I don't have any kind of measurement that i could do in regards to float level as they will usually give you something in a rebuild kit i've just never rebuilt a 4 barrel before so i don't have any of the little do-dads that you might acquire.I will check the ignition stuff tomorrow is there any way to definatively check the condition of the cam? I do know this in that when i first dropped the disto in it would run like crap at idle doing what it does now at partial throttle the popping and backfiring right at idle so i fiddled with and tried to dial it in better and now it runs great at idle once its warmed up but the **** is a little further up in the band now - Talk to ya' thanks for your help - We would'nt do it if we did'nt enjoy it right? Oh yeah,rotor turning counter clockwise? it would have to otherwise the engine would be dieseling would'nt it?

 

Ok,compression is 145 in 5 cyl's,140 in 2 & 135 in the lone remainder - not bad at all for a 42 year old truck ! and i know it was used with a camper on it and towing god only knows what - I have not gone thru the entire motor bringing each cyl up to tdc and checking rockers - as of yet..Tomorrows a new day.Now i have many times with # 1 and there is no slop.As far as miles? again god only knows i do know the dufus i bought it from had'nt registered it in 5 years,and apparently he knew the people he bought it from who lived in Az where it sat for a while as well so he may not be to blame for all those years of non registration now why those clowns could'nt have non-opped it is beyond me - and that was LAST year which is the main reason its not registered and transfered into my name yet as the dmv wants $500 + so i need to go in and counter that - which i want to get it all back together.The guy who did the carb will stand behind his work in that you need to bring the vehicle in - well his shop has got to be the better part of 35 freeway miles away one way so i'm in between our friend the pet rock and his buddy hard place on that for the moment.I'd thought burned valve almost immediately too but it idles perfect you cap each pipe and it blows your hand off as it ticks em' off theres not really any hint of anything that sounds outa whack in the exhaust note right there,and if you had a bad exhaust valve i'm thinking you'd also hear it there as well.How can you check a timing chains condition? reliably?

 

Ok i have to keep going back rereading and posting more info - it ran somewhat up until around 50-55-60 and then would start crapping out like it had a fuel delivery issue - which given sitting for a couple a hundred years should'nt be a surprise,right? So i changed the fuel filter and good lord there was about an 1 " of crud in the bottom of the canister - no real difference.Put some STP fuel system cleaner in it - big,BIG mistake it really ran like **** then.I think thats when it really started - Shoulda known anything made by STP is worthless - So i said well i'll get the tank cleaned i started looking and it was almost as much as what a new tank would cost so i bought a new tank and fuel lines when i got under there and started seeing what re-placing the original steel line would've entailed i said screw that and ran 3/8's fuel hose all the way up to the pump.Its also got a new pump not rebuilt - Its got the 600 carb - originally it had an Edelbrock 750 Performer on it which if i put a garden hose in there i probably would've gotten better mileage - That was rebuilt as well but it still ran ****ty not doing what it is now but just not running well,still had the issue where it almost seemed like it was starving for fuel - It had a stock 390 4 barrel iron manifold so i took that off with a crane and put an aluminum Edelbrock manifold on it as well - The headers were on it with funky glasspacks as thats all that would fit with the saddle tank which i ripped outa there so i can redo the exhaust right - but it still has the packs on there.The MSD stuff box & disto mild hot rod stuff nothing outlandish i gave up with the stock disto and trying to get a Pertronix module to run right in it thats when i said the hell with it and got the MSD one - Getting it started has always been a bitch this is the best its run in that regards i can almost just tap the key with a single little blip on the throttle and it fires right away and once it warms up it idles great its just at partial throttle so its making progress but its obviously got something amiss somewhere -