351W stroked to 408, overheating
 

Gentlemen:

While searching the internet for other people with my same problem I came across this www site for Cobra enthusiasts and thought I might partake of your knowlege..

I own a full size Ford Bronco that was born with a 302 in it.
Several years ago I pulled out the 302 and put in a 351-Windsor stroked to 408. The engine is as follows.

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351W EFI Bored & Stroked to 408
Accel Fuel Pump
Automotive Racing Products (154-3603) Cylinder Head Bolts
Clevite Engine Parts, Main Bearings, LE-MS1432P
Clevite H-series Connecting Rob Bearings, CLE-CB663H
Cloyes Timing Chain
Competition Cams Hydraulic Roller Pushrods
Eagle Specialty Products 3-D Rods
Eagle Specialty Products Forged 4340 Steel Crank
Edelbrock (3838) 61mm Twin Throttle Body
Edelbrock (3881) Performer Truck Aluminum Upper & Lower intake manifold
Edlebrock Plenum Chamber Gasket, EDL 3832
Edelbrock Performer 6037 Aluminum Cylinder Heads
Felpro Intake Gasket, 1250FEL
Felpro Oil Pan Gasket, 1810
Ford SVO M-6250-E303 Hydraulic Roller Tappet Camshaft
Ford SVO Hydraulic Roller Lifters
Ford SVO Aluminum M-6582-B351 Valve Covers
Ford SVO F3ZZ12-A-650-FB EEC-IV Mass Air Computer
Ford SVO M-12071-C302 Multiport EFI Wiring Harness
Ford SVO M-12071-D302 Sensor and Relay Package
Ford CVO M-12071-E302 Engine Harness & Controls
Ford SVO M-9593-B302 EFI Hi-Flo 30lb Injectors
Jacobs Ultra Team Ignition
Jacobs Opto-Timer Deluxe
JBA Shorty Headers
JE Forged Pistons, 9.6:1 compression
JE Plasma Ceramic Rings
Melling (83) Hi Volume Oil Pump
Michigan 77 Bearings
Michigan Cam Bearings
Mr. Gasket Intake Manifold Bolts
Napa Aux Oil Cooler
Napa Starter
Superchip Custom EEC chip
Vortech Mass Air sensor
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The first build on this engine suffered the following fate
3 pistons had rolled skirts and the other 5 pistons were scored from excessive heat. Cylinder heads were warped, the head gasget blew out, Rings and main bearings were toasted.

In short the first engine melted.

That engine was stripped down and completely rebuilt and a new 3 core aluminum radiator was installed which seemed to help quite a bit.
BUT...

Right now, on long uphill grades, the oil temp gauge pegs the needle past 250, and thats WITH an Aux. Oil Cooler running Mobil One synthetic Oil.

Normal midsummer driving around town the

Outside Air = 110 degrees
Water Temp = 210
Tranny Temp = 180
Oil Temp = 230

Under any real load the Oil temps shoots up, the water temp follows very quickly and there is detonation to be heard in the engine.

Where should I be looking for the source of all this heat ???
Bad Chip?
Bad Cooling System?
???

lean mixture
 

This sounds like your engine is running very lean. I would not run it any more until you find out why it is running so lean. Bring it to a tuning expert. It could be as simple as increasing your fuel presure or swapping out some bad o-2 sensors.

I would tend to agree with you but for the fact that I have an air/fuel mixture gauge on the dash and it suggests that this is not the problem right now.

But, lets say that it was.
WHO in southern California could burn me a new custom EEC chip while running the engine live on a Dyno ??

I would be more than willing to give that a try.

Hi,
Right off the bat you're water temp is at 210 ?
That's too high, put in a 180 thermostat and drill a small 1/8" hole in it so air will bleed out. While your at it make sure you have the correct water pump, they can rotate in either direction, depending on year. Take the rad cap off when engine is cold and start it. the water should flow from the top hose and go down through the rad.
Take a timing light and check the static timing of the engine. Pull out the small black shorting plug in the distributor wiring first or the computer will advance the timing and give you a wrong reading. The static timing should be at 10 degrees BTDC. Your superchip should give you all the advance you need so don't advance the initial timing to 14 or 16 degrees like some guys do.
If you still have a catalytic converter on your truck, it could be plugged or collapsed inside, if it has more than 50 k on it -replace it with a high flow one.
You will need to check these things 1st or have someone check them before you spend money on a dyno or engine analyser.
Good Luck,
Perry.
:cool:

Perry:

I have a counter rotating water pump on the engine.
I have a 180 degree thermostat or LESS currently installed.
I will have to check on the timing, but as I recall, it is retared back off TDC.
I have a High Flow Catalytic converter with less than 5,000 miles on it.

Hi,
I would have bet a water pump problem seeing as your air/fuel ratio was ok, you sure it's pumping the right direction?
How about the radiator fan shroud, I put one from a 88 lincoln on my cobra rad, it dropped the temp 20 degrees. A large flex fan would also help move some air.
Do you have a vacuum or mechanical shut off in the heater hose line, if not hot water will bypass the rad ,just goes from intake to water pump and can raise the engine temp when hot out.
** If you can hear detonation, it's damaging to the engine. I would recheck the initial timing, in some cases the marks on the harmonic balancer are not correct and can throw off setting the timing. Try finding top dead center,pull pass front plug #1 and move to top on compression stroke. Then check marks on balancer.
Not much else to check except for the chip?
Perry.:cool:

maybe comp ratio
 

I was thinking about your problem and I wondered if you ever CC'ed the cylinder heads and acurately measured what the compression ratio was when the motor was built. If its more than 10.8 to 1 this would cause this type of problem. Have you tried making the motor run rich to see if the temp comes down. It could be timing as was mentioned earlier.

I just checked an edelbrock site and it lists the heads you are using as having a 60cc volume. I plugged in 4.030 bore 4 inch stroke .040 gasket thickness 4.030 gasket bore with zero deck height and came out with 13.235 compression ratio. Unless these heads are bigger or your pistons are dished this could be the issue. Of course the deck height will be a few thousands.

HighPlainsDrifter:

I do not know for a "fact" which direction the water is flowing.
But this evening I will open it up and take a look to confirm.
With a reverse rotation pump, should the flow be going from TOP to BOTTOM or from BOTTOM to TOP ??

OEM Fan shroud is in place, with a new fan and fan clutch.
Its moving a LOT of hot air.

The heater hose line is mechanical from the dashboard.
When the engine gets HOT, I run the heater wide open for extra cooling. What your saying sounds like that might be counter productive???

The detonation ONLY occurs when the engine is HOT.
Under all normal conditions the engine runs great with no problems. I just drove it to Las Vegas and back 300 miles with NO problems at all, but right now the ambient temp is down in the 70s where as in the summer its in the 110s.

The CHIP is my current target.

Looking for someone who can burn me a custom chip with some LIVE DYNO input....

408cobra:

Its an interesting thought.
I don't know if we have run a compression check on the new engine or not. I do know I was told to never run less than 91 octane in it after we started trouble shooting it.

How do I make this engine run RICH when it is computer controlled????


The original spec on the engine was to be...
9.7 compression running 85 octane pump gas.
1500rpm = 352hp
2000rpm = 376hp
2500rpm = 396hp
3000rpm = 421hp
3500rpm = 423hp
4000rpm = 423hp

408cobra:

DAMN!
If there is any possibility that I am running that kind of compression, that would explain everything in a heartbeat.
I really can't imagine they would have let it go out the door with that though. That would be just gross negligence.
But I can sure get it checked easy enough to know for certain.

Turn up your fuel pressure (I assume your running an adjustable Fuel Pressure Regulator). The computer assumes that the injectors are getting fuel at 38 psi (the stock FPR setting). If you adjust the fuel pressure above 38 psi, the injectors will be spraying more fuel per pulse than the computer thinks, thus making the mixture richer. Of course this will only make small changes to the mixture as the computer is basing the amount of fuel on the 02 sensor readings.

About your chip - I have read a lot of good things about
Johnson Motorsports chips, and some not so good things about Superchips for highly modified engines.

You might ask for some advice at The Corral . Lots of knowledge there about stroked Windsors and Ford EFI.


Pete

PSB:

Johnson Motorsports is in Alabama.
That would be a pretty fair drive from Arizona to get some Dyno Time.

Any idea of a similar shop in ...
Las Vegas?
Southern California ?
Phoenix ?

I am up for a 4 hour drive.
But not several days...

compression
 

I checked the je web site and they have one piston that will work with your combo. I assume it is a 4.030 bore with 4 inch stroke and a 6.2 inch rod. It is listed as a 9.6 comp ratio with 58 cc heads and has a negative dome of 30 cc's with this piston your comp ratio would be 9.503 using a zero deck height and a .040 thick gasket with a bore odf 4.030. This would work fine in your setup here is the part number 170393. Keep us posted on your findings. Good luck this is a weird one

Thanks.
I went over to corral.net and joined there and have reposted the same questions to see if anyone there has a different take on this beast.

There are a lot of guys at the Corral that have had good luck with JMS ships via mail-order. No dyno time required.

Pete

You appear to be willing to try just about anything.

You may or can try a thermal imaging system.

Can't help you on who or where, but a PM380 or better camera will allow you to record on video tape the engine from cold to hot.

You might be amazed at what you find.

If you can find a person in your area that will video it for you, have it stored on video tape. then you can go back and look at the engine in time.

I use one on an engine once to find that there was a chunk of metal in a cylinder head. I don't have access to the camera any more.

Just my $0.02
:3DSMILE:

PSB:

Could well be.
But after 3 chips I really want to be 100% CERTAIN the next time around that the chip is simply not part of the overheating equation. Thus far no one has had a near by location suggestion.

trularin:

Now that is what I call OUT OF THE BOX thinking !
Thats a darn interesting idea.
Not a snowballs chance in hell of finding that kind of technology in this town though. At least I sure wouldn't think so.

The one comment they have come back with over on corral.net is that the radiator may just be too damn small.

Even though it is an upgrade to the OEM unit, it is still fitting within the OEM Dementions of the truck, and thus they are suggesting that its just to small for what is now a big block engine.

Could it be that simple?
Would that in any way account for the HIGH Oil Temps I see ??