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Input on 363ci Fueling Issue - Headgasket checked out

4K views 69 replies 9 participants last post by  Macd7919 
#1 · (Edited)
Hey guys, I’m looking for a bit of input from people with similar experiences on a fueling issue I’m having. Once again this car is testing my patience to the max. Here’s a few relevant details on my build:

FordStrokers Dart 363
Custom cam from Woody
11R 190 heads
Billet 7875 Turbo Setup
Glenn’s Performance 1000hp Fox Fuel Kit
- I went with an Holley 525lph pump assembly (complete drop in assembly with billet hanger) instead of the Glenn’s Walbro 450 pump. Lines are -8 supply and -6 return from Glenn’s along with a -12 in/out fuel filter and Glenn’s FPR.
Deka 80lb injectors (authentic, not knockoff stuff)
BBRC Rails
Terminator X for tuning
Fel-Pro MLS head gaskets
92 octane fuel
I have an upgraded alternator and voltage stays steady near 13.6-14.2 volts at rpm.
No leaks have been found or evidence of fuel leaking under pressure.
Feel free to let me know if I left anything else that’s pertinent out.

We were on the dyno tuning the car, data logging each pull, and progressively raising boost via the Hallman manual boost controller. All was well and the car was making solid power. We were nearing our target boost level and at roughly 5500 rpm the head gasket blew with the expected coolant everywhere and billowing white smoke from the exhaust. Based on pulling the plugs it looks like cylinder 5 let go, which is fueled by the first rail on the supply feed from the pump (I feed the driver side rail, from driver to passenger rail, then from back of pass rail to FPR). At the time of the failure the car was making 640whp (5500rpm) and 670wtq (4300rpm) on a Mustang dyno with past runs showing peak hp at 6300rpm so we weren’t even at max power output when it let go. Timing was at 12 degrees and AFR was 11.2-11.5 up to the point where the pressure fell off a cliff. The tuner let off as quickly as possible but the head gasket went almost instantly. We went back and looked at the logs and at the time of failure we were at roughly 16lbs (1-2psi over our target but shouldn’t have been enough to blow the gasket) of boost and injectors were flowing a bit over 500lbh. Fuel pressure was at 60psi and then dropped like a rock to about 40psi (I will confirm exact on data log) and pop went the head gasket. When the fuel pressure started the drop the Holley did try to compensate and the injector rate rose to 80% but it wasn’t enough. Luckily it doesn’t seem like the block was hurt and there is no coolant in the oil.

Everything in the fuel system is brand new and has roughly 200mi on it. The fuel pump is powered by dedicated 10ga power and ground wires and is fused through a 40A circuit breaker. The breaker did not trip. As there are only so many components in the fuel system, I’m leaning towards this being a pump failure to perform in some manner. Maybe it got hot from repeated pulls and couldn’t keep up? Aeromotive specifically tells you to place the return line in the baffle box of the tank where the pickup is, could that have caused aeration and led to a failure? Seems like the car would be using more fuel under boost and returning less? The FPR seemed to be doing its thing as it was seeing 60psi and rising as expected.

Has any one had a similar issue? Are these Holley pumps junk or maybe I just have terrible luck? I had a Aeromotive 340 pump fail on me before (it was just completely dead as where my current pump still primes up to static pressure). I’m frustrated with the car and now I’m going to be replacing head gaskets and I sure as hell don’t want to retain the fuel system as is if it’s insufficient, but I’d also like to not just throw parts at it. Any input would be great from people who have experienced similar issues or if there’s something I’m missing with the fuel system.

Here is a link to the exact pump I’m using:

 
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#60 ·
Might be the safest thing.. Some people are putting a psi sensor in the radiator to monitor coolant pressure and use as a fail safe sensor. If a gasket starts leaking into the coolant, even slightly, the pressure goes up and can be seen as something changing then replace the gasket before a major blow. If the gasket completely goes the sudden pressure read by the ECU can shut the motor down faster than we can lift off the gas.

ks
 
#61 ·
Got the driver side head off. Nothing jumping out at me on headgasket damage. Many I’m not looking for the right thing. The hot side crossover pipe from the driver side to the turbo manifold is full of coolant. I cleaned the pistons and they look good. No evidence of dull spots or damage. A couple pics below.
 
#65 ·
The guy tuning it said Cyl 5 had coolant on the plug, and when I pulled the plug in Cyl 8 it also looked “wet” but in hindsight I’m wondering if that was residual as there was quite the explosion of coolant when the gasket(s) went. I was standing on the pass side of the car when it went and to me it looked like it came from the driver side. That side of the car engine was also pretty well coated in coolant as where the driver side and head looked pretty much dry. Cyl 1 was def full of coolant though. When I pulled the plug a bunch came rushing out, and then when I turned the motor to TDC to pull the distributor more came out. My hot side crossover piping also has a decent amount of coolant in it. Haven’t gotten to draining that yet. Hoping to have the pass side head off within the hour.
 
#66 ·
Update:

I’ve found the issue. The passenger head gasket was blown on Cyl 1. Both into the cooling port and at the top of the gasket. I was also politely notified that I am an idiot (my words, not theirs, they were very polite about it) that I put the head gasket on backwards on the driver side when I installed the heads. It looks like this oriented the “large” coolant ports in the gasket to the front of the head and the ports with the 1/4” ports to the back of the head when the gasket should have been reversed. Apparently the “front” stamped on the gasket didn’t register with me at the time (working on it late/tired), so that’s one thing that probably didn’t help things. Oddly enough the car always ran cool (180f stat, high flow water pump, large radiator, good electric fans) but that doesn’t mean that head wasn’t hot or cyl 1 wasn’t hot. Luckily the pistons look fine and everything is shiny after a wipe down with carb cleaner.

I also cleaned up the heads and found that the head with the blown gasket has a gouge in it right about the spot where the gasket ended its life. I measured the gouge as best I could with my calipers and it’s about 0.01” deep so it’s looking like I’m in for a new head or a repair. My concern with the repair is that the motor is built for 9.5:1 compression on 58cc heads and I’m already on 56cc heads. I don’t know if I have much leeway with welding and then removing material while maintaining any room for error on a turbo car running 92 octane. Planning on calling Woody tomm for some advice and also the head repair shop to see how much such things run these days.

Anyways, what looked to be a relatively relieving day of no major damage outside of gaskets has turned into head damage. Not much I can do about it at this point but swallow the pill and move on/look at some options to get back on the road that will fit my long ago dwindled budget for this build.

Automotive tire Synthetic rubber Rim Automotive exterior Automotive wheel system

Sleeve Bag Personal protective equipment Pattern Luggage and bags
 
#68 ·
Thanks for the input, Jim. There is a shop about an hour from me that supposedly does good work and specializes in aluminum heads. Going to give them a ring tomorrow and see what they can do. Hopefully cost wise it’s significantly less than a new head.
 
#70 ·
To anyone reading the down the road, I dropped the heads off at the shop mentioned above before leaving town for a couple weeks. Came back to the heads being done (small gouge welded, heads decked 0.003” each, and valves checked for leakage). Total cost was $285 out the door and you couldn’t tell they’d ever been touched.

The heads are back on the car now. I took the car for a light spin with boost turned down (mostly just to burn some fuel off before dropping the tank) as I knew from the dyno runs (prior to the HG going) at low boost everything was far into the safe zone. For fun I took a data log and made a short pull on the highway.The pump isn’t keeping up even at low boost. On the log the pressure had dropped as low as 23psi. I had a few minutes of great concern as the car ran very lean for a few moments (14:1+). Crap! I pulled the plugs and checked them all and they looked OK. No shiny specs, melting, or otherwise. No smoke from the car or funny sounds so it would seem things are good and I got lucky (timing was also low).

Got to work dropping the stock tank on Sunday, got that out, prepped the new BBRC tank and Fuelab pump and am working through the last bits of that install and then contorting myself to get a set of fresh plugs installed. Then once fuel pressure is confirmed as holding its back to the dyno to finish the tune and start making some power.
 
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