Timing issue
#1
Timing issue
I have a weird timing issue with my 88 5.0. The engine in the car is a 96 Explorer engine with 4K miles since overhauled. It has the iron GT40 heads milled .010 with some bowl work and a nice port job. They have CompCams springs and such on them. It has a TrickFlow Stage one camshaft. The thing runs great but has always felt a bit sluggish at part throttle so I started advancing the timing.
Anyway, the issue is that the car runs best with the timing set at 25* BTDC. It doesn't drag the starter when hot and has not detonation. Not even with the a/c on and temps in the mid 90's.
My though was that the balancer had slipped. No big deal, ordered a new Professional Products steel balancer and spacer. Put it on earlier, shecke the timing again, it is at 28*. And before anyone ask, yes this is with the spout connector unplugged. I backed it back to 25*. Turned it off, reinstalled the spout plug and started it up. It now reads between 30* and 40* depending on throttle position. About 30* at idle. It runs strong with no detonation. I'm just baffled as to why it is so high? My original 5.0 that is sitting in the garage ran best at about 14*. C&L said with my 24# injectors and a brown sample tube in my 73mm MAF that 15* made the most power in their dyno test. I'm 10* off, anybody got a clue?
Anyway, the issue is that the car runs best with the timing set at 25* BTDC. It doesn't drag the starter when hot and has not detonation. Not even with the a/c on and temps in the mid 90's.
My though was that the balancer had slipped. No big deal, ordered a new Professional Products steel balancer and spacer. Put it on earlier, shecke the timing again, it is at 28*. And before anyone ask, yes this is with the spout connector unplugged. I backed it back to 25*. Turned it off, reinstalled the spout plug and started it up. It now reads between 30* and 40* depending on throttle position. About 30* at idle. It runs strong with no detonation. I'm just baffled as to why it is so high? My original 5.0 that is sitting in the garage ran best at about 14*. C&L said with my 24# injectors and a brown sample tube in my 73mm MAF that 15* made the most power in their dyno test. I'm 10* off, anybody got a clue?
#3
I would if I has one. I'm not going to buy one just to test it. I already blew $100 on the balancer which is a nice upgrade, even though it didn't fix my issue. It runs fine, as is, I just have never run into this issue before in my 27+ years of working on cars.
#4
If you have been working on them for that long, you know that you can build 2 motors exactly the same and they will run the best at different timing. Granted I have never seen one do that either besides one that had a distributor going bad and it wasn't a ford. With the timing being the same every time you check it, I would just run it as it is until it starts to give me problems or at least think of something else it could be. I would think with lower compression you could run more timing but, since you claimed you raised it, I don't know.
#5
Yeah, Maybe the crank was machined just a bit off for the balancer key when it was made or something crazy like that. As long as it runs good, I'm just going to let it ride. The timing stays very consistent so I don't think it's the dizzy. and yeah, the heads were milled .010 so I don't think I'm running 7.0:1 compression
#8
Have you got this figured out yet? I am in the same boat. I have a 65 mustang I put a 2000 explorer engine in and converted it back to distributer instead of the crank angle sensor and coils. If i set the timing by ear i can get it to run decent but its too advanced to turn over when it gets hot. If i set it with a timing light its way off, probably like you said 30+ to advnced. Ive screwed around with it for years on and off, im sick of the thing
#10
Just an update, the guy that I bought the engine from had put the cam in 4* advanced and it was off a tooth from that. Installed a new CompCams double roller timing set straight up and it is back to where it should be. Runs better now too Imagine that!!