[Nova_MRP]

Ok so for starters I have a 95 mustang cobra with a on3 turbo kit. For a while now the car has basically been undrivable at speeds due to timing being retarded starting from about 1800 rpm and progressively getting worse till around 4krpm. This issue is still present whether the spout connector is in place or not, the only difference is that with the spout in the computer advances about 3-5 degrees but then starts retarding around 2k rpm till it finally won't rev anymore after pulling around 20+ degrees.
I have tested spout voltage at the tfi module and with spout OUT voltage sits around 5.1- 5.3V. At idle spout connector IN voltage raises to around 8.8-9V but as I raise rpm voltage drops to 3.3volts and stays there. Could someone tell me if this is a normal reading or what could be causing timing to be pulled with/without spout?

 

[Ilusivefox]

What tuning software or chip are you using? What injectors what fuel pump? Need more info.

 

[BDFG]

When was the engine last built, or when was the timing chain last replaced, then what timing chain set was used? I used to run into this problem a lot, for multiple years, most every car I worked on, that had a freshly built engine, had this same problem. I kept finding the Chinese made cam sprockets were eating up the cam thrust plate, causing the timing to retard. It would do this, inside of 1000 miles, often at 500 miles after a fresh build, I would be getting 20 to 25 degrees of timing retard. Engines that had 1000 to 2000 miles on them were retarding the timing more like 30 to 35 degrees.
I replaced a lot of timing chain sets, that had less than 2000 miles on them.

 

[HYBRED]

It’s supposed to retard the timing when you go WOT, then bring it back in.

so what are the timing values you are seeing, and at what rpm / load?

what is being demanded?

sounds like you just have a terrible tune or none at all.

 

[Nova_MRP]

It’s supposed to retard the timing when you go WOT, then bring it back in.

Well the base tune was working fine for the 1000 previous miles and nothing was changed when it started to act up. I don't have any aftermarket ecu/piggyback yet so I'm not positive on the load maps.

 

[Ilusivefox]

How was the base tune done? Chip? How are you turning the timing down? Msd BTM?

 

[Ilusivefox]

Trying to figure out what exactly you mean by a base tune because a base tune should only be used to get it started get it running idling maybe a quick small test drive/shake down run test drive at part throttle then take to dyno or dyno tune to be custom tuned and or have a tuner involved that knows what he is doing. Putting 1000 miles on a base tune with a turbo is asking for problems.

 

[Dwain]

When your car has the suspected timing issues, what is the tach doing?

 

[HYBRED]

So you have no tune.

with a turbo, (or any forced induction), the timing needs to be addressed, especially in the mid range rpm, because Load values quickly surpass 100% even as low as 2500-3000 rpm.

If you’re lucky, it’s just “spark blowout” but it’s more than likely detonation that you are experiencing. Or lack of fuel, who knows.

cheap turbo kit + no tune = kaboom

 

[HYBRED]

The J4J1 is on the stock tune if it doesn’t have a chip, …. So too much timing and probably not enough fuel.

does he have a FMU?
Does the have any sort of BTM?
A sufficient size injector & fuel pump?

OR just a “calibrated” MAF? 🧐

 

[Riverwabbit703]

Ok so for starters I have a 95 mustang cobra with a on3 turbo kit. For a while now the car has basically been undrivable at speeds due to timing being retarded starting from about 1800 rpm and progressively getting worse till around 4krpm. This issue is still present whether the spout connector is in place or not, the only difference is that with the spout in the computer advances about 3-5 degrees but then starts retarding around 2k rpm till it finally won't rev anymore after pulling around 20+ degrees.
I have tested spout voltage at the tfi module and with spout OUT voltage sits around 5.1- 5.3V. At idle spout connector IN voltage raises to around 8.8-9V but as I raise rpm voltage drops to 3.3volts and stays there. Could someone tell me if this is a normal reading or what could be causing timing to be pulled with/without spout?

I had a 94 Cobra with P1 super charger, besides the blower, the speed shop told me in order to run boost, I had to get a bigger fuel pump, blow through MAF, injectors, colder plugs, intercooler, computer chip and dyno tune to get correct timing and fuel curve through out the RPM band or I would end up with holes in my engine. If you‘re throwing boost without correct fuel or timing with supported mods, it’s ticking time bomb.