460 engine failure 800 miles street use

We disassembled it per the machine shop instructions so they were involved every step of the way. The head gasket was NOT installed backwards because we matched up a new one to the old one and everything is exactly as it should be (blocked in the front and open in the back). The theory the machine shop had it that there may possibly be something off with the time advance curve in the SD computer itself or a problem in the new distributor causing the same problem. They thought predetonation was the culprit. I'm confused at to why only 3 cylinders were affected in the whole motor (all the rest were carboned up due to too much fuel and no enough air).This motor takes the place of exactly the same build 7 years ago. The old motor broke the camshaft teeth and the distributor teeth beyond repair. The SD computer is the same exact one. The only other difference between the old motor build and the new one were the installation of 30lb injectors to try to get more pick up out of the new motor.

Like Randy said, you took it apart. Good luck. Even though they are at fault. It will be a BIG headache getting anything out of them. Probably cheeaper to chalk it up to lessons learned than take them to court......
For a civil case suit around here, the lawyer retainer fee is $5,000.

Just salvage the ole girl. Plenty of good help here as well as reasonable parts.

Best wishes.
Al

7 and 8 fire in sequence.  Cheap wires can induce a spark in 8 way before you want it.  If inductive induced detonation was the cause then once the gasket was blown between 7 and 8. The intake charge gets all messed up with cross feed pressures etc.  Can then sequence out other cylinders due to lean conditions.  Just the issue with being excessivly rich can cause the rings to wash out and let oil get into combustion chamber.  Oil contaminated fuel detonates at a very low pressure.

When using an OEM computer calibrated for THAT same vehicle, do not increase the injector size but, simply get an ADJUSTABLE fuel pressure regulator to increase pressure a bit and therefore a richer air/fuel ratio at Wide Open Throttle.

No need to even do that if everything else is as OEM delivered because it is about 4% to 7% rich from the factory ...  I suspect it is not as it was delivered new.

how does an adjustable fuel regulator get mounted to a triangle plate as comes with an oem fuel regulator?

Problem with these threads is all the important information needs to be pulled out of the poster. Wastes a lot of time and of course the OP gets annoyed.

Now that we established the head gasket was on right looking at the big burn out between 7 & 8 would say is safe that the spark plug wires were touching and was cross talk. Is easy enough to verify. Look at the wires for any burn marks. Failure started at 7 & 8 and was just progressing to 5 IMO.

They sell adjustable fuel pressure regulators that bolt to the stock fuel rail. Running a 30# injector on something calibrated for a 24# injector will not work. That is a 20% increase in fuel. Engine must have been pig rich.

mgawat wrote:how does an adjustable fuel regulator get mounted to a triangle plate as comes with an oem fuel regulator?

Three bolts

the aftermarket adjustable fuel regulators I've seen come with a nipple not a plate and I can't see where there is any nipple associated with the OEM ones. Also;.l 7 and 8 spark plug wires were completely seperated and have no burn marks on them.

I melted up a sbc head and burnt the gasket EXACTLY how you did years ago as a novice on an aggressive NOS tune. Car was pulling like f__k before it no pulled no more. lol. Lean and too much advance as was previously said. Good luck with the reassembly.

The other head was ready to let go also and rods showed predotanation signs on the bearings...Pretty much convinced faulty ECM did this

mgawat wrote:the aftermarket adjustable fuel regulators I've seen come with a nipple not a plate and I can't see where there is any nipple associated with the OEM ones. Also;.l 7 and 8 spark plug wires were completely seperated and have no burn marks on them.

Then you haven't seen enough of them. I know that BBK sells one and there are others.

One of these?

thank you...what is the manufacturer and number ?

Lastly, How does one install a fuel gauge into the stock fuel rail circa 1995 7.5?

Most simply use the shrader valve on the fuel rail. Otherwise you have to put a T in the delivery side before the fuel rail, wich involves cutting the stock braided steel Teflon lined fuel line. Using AN adapters and a T and then another AN adapter to factory rail.

thank you

mgawat wrote:thank you...what is the manufacturer and  number ?

http://www.kirbanperformance.com/product/776/Mustang+BILLET+ALUMINUM+ADJUSTABLE+FUEL+PRESSURE+REGULATOR+%235005.html

thank you...part ordered. I appreciate the help...especially when some folks just want to give attitudes.

Problem isn't the fuel pressure regulator. EFI is going to use the O2 output and cut injector pulse to keep it at 13-1 or as close as it can. Adjustable pressure regulators are very bad crutches for people who don't buy a large enough injector. 38 psi is common ford base fuel pressure, no vacuum. When you hook up vacuum then the pressure feed will reduce at idle and ramp back up to 38 psi at WOT or low vacuum