Car stutters at 4000rpm+

Boss 351

Here sthhhhhhhheeeve take a picthh of my man flowe
Jul 13, 2003
2,433
23
48
Canada
At first I thought it was my old stock fuel pump so I put in a new 190lph but the problem is still there.

It feels as if the timing is WAY off. I set the timing at 14 with the bypass unplugged but as soon as I plug it in, the computer will advance the timing to 20 something at idle and will go up to 42 at 3000rpm??? WTF. I put it at 10 degrees for now. HOWEVER that could be my timing marks, I may have missed TDC because spark timing problems would show when the engine is cold too.

The kicker is that when the engine is warm, it will be VERY hard to start as if the starter is having a hard time to turn the engine, it will start at 1/4 turn just the same but it feels like the engine is siezed. Starter is NEW, battery is new and I have a new 3G alternator. That 1/4 turn is a very slow turn.

I'm starting to think it's a bigger problem like my lifters collapsing when the oil gets hot, not enough pressure in there to open the valves like they should. I made the mistake of not getting NEW lifters when I put the engine back together. :rolleyes: That would explain the hard to start thing because it really feels like the starter is having trouble to turn the engine (anyone experience hydrolock, it feels like this almost).

It doesn't help that I have dual valve springs good for up to 560 of lift and I still have the darn stock cam and old lifters. :bang: I adjusted my rockers about 5 times on this using all the tricks, I even used a dial gauge to set the lifter pre-load properly... I noticed that, while doing this, a couple of lifters would NOT hold any charge even at 0.010 load. Adjusting by sound would work but by the time I do one side, the other will start to tick LOUD...

DO you think the high spring rate + low cam + old high mileage lifters + real thin and warm engine oil could cause the valves to not open fully and more importantly on time? :bang: I guess I sort of answered my own question with my rant/question lol I'll replace the thin 10w30 with some 20w50 and see if the situation improves a little...
 
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All these symptoms sound like mine. Hard start when warm, no power over 3k rpms, etc.. I've changed cap, rotor, wires, plugs, and the fuel filter. To make it even more fun, after I got done checking fuel pressure(41 psi with vaccum line off, 29-31 with it on) and timing(bumped it up to 14) last night, I went for a ride and the car ran perfectly. Only code is an EGR code. I don't have the timing going crazy like yours tho.
 
my cap, rotor, wires, plugs are all new... although I have "gulp" crappy Champion (champ-pee-on) plugs on there... I'm going to recheck my timing marks at TDC, if the timing is retarded too much, I could see that sort of problem I'm describing... I hope it's a simple fix.
 
Well if you're running a 351W with a Ford starter, you can get used to it lol... I.m not sure why either but every one I've had over 9:1 compression has done the same hard start thing and I've found absolutely no cure for it. I have one right now with 8.5:1 and the timing is set at 33 degrees total advance and this one will turn fine for about 3 cranks before it gets slow, also with a new starter and battery. As far as your crazy timing marks go, I had the same problem with my current Windsor. To even get it to run, according to the balancer, I was at like 72 degrees! I readjusted the valves and put in a new set of plugs gapped to .045 and it popped right off and read 46 degrees....... WTF!... So I checked my TDC again using tho old spark plug and a bolt method and I ended up bieng 10 degrees off on the TDC mark... I re- marked it and set it to 33 and it goes like a raped ape AND it even starts when it's warm...
 
Well I put in a higher grade oil (20w50) and I advanced the timing (without a timing light) and the stuttering went away. So it's a timing issue, I'm going to remove the dizzy and find TDC so I can put my timing marks at the right place and time her properly. Oil pressure goes up to 60 cold and will go between 20 and 50 depending on RPM at 180 degrees. :D

pheww it was only a stupid problem... haha I was the problem :rolleyes: