slate blue

Guys long article well worth the read, has many aspects that relate to 928 engine modification, such as cams, oiling, piston squirters, tri-y headers, head flow etc. It really has huge headflow, fairly similar to my 4V port work but theirs is bit better despite slightly less flow because their valves are smaller, 37 mm just like the 928. As the engine is 5.0 liters in size it is a good comparison and after reading about the trouble the engineers had, no wonder we have had teething problems along the way. Here is the basic spec of the engine.

http://www.mustang50magazine.com/tec...ine/index.html


2011 Ford Mustang GT 5.0 Coyote Engine
5.0 Tech Specs
5.0 4V TiVCT V-8

First Model Year 2011
Engine Family Modular
Code Name Coyote
Displacement 4957cc (302 ci)
Bore x Stroke 92.2 x 92.8mm (3.263 x 3.647 inch)
Horsepower

412 hp @ 6,500 rpm, 91 octane
402 hp @ 6,500 rpm, 87 octane
Torque
390 lb-ft @ 4,250 rpm, 91 octane
377 lb-ft @ 4,250 rpm, 87 octane
Shipping Weight 430 pounds, includes water pump
Block Low-pressure cast 319 aluminum, pressed-in thin-wall iron liners
Bore Spacing 100mm (3.937-inch)
Deck Height 227mm (8.937-inch)
Deck Thickness 13mm (0.510-inch)
Cylinder Head Retention 12mm bolts, 4 per cylinder, 10 bolts total per bank
Oil 5W/20 weight, mineral
Oil Pan Stamped steel, 8 quarts
Windage Tray Integral w/oil pan gasket
Oil Pump Gerotor
Pistons Hypereutectic, short-skirt, flat-top w/four equal valve reliefs; moly friction-reducing coating; oil-jet cooled
Piston weight 500 grams
Piston Pin Full-floating, 22mm diameter
Piston Pin Retention Wire lock
Piston Rings 1.2 x 1.2 x 2.5 mm, moly top ring
Connecting Rod Powered metal forging, I-beam, no balance pad
Connecting Rod Length 150.7mm (5.933-inch)
Rod/Stroke Ratio 1.62
Crankshaft Forged steel, fully counterweighted, induction hardened
Main Journal 67.5mm (2.652-inch) diameter
Rod Journal 53.0mm (2.082-inch) diameter

Flywheel Retention Eight-bolt
Cylinder Heads Aluminum, four-valve per cylinder
Head Bolts 12mm, four per cylinder
Valve Covers Composite
Compression ratio 11.0:1
Valves 37 x 31mm (1.454 x 1.218-inch), four per cylinder
Camshafts DOHC, four camshafts, independently adjustable timing
Camshaft Timing Twin independent variable
Duration 260 degrees intake, 263 degrees exhaust
Lift 12mm (0.472-inch) intake, 11mm (0.432-inch) exhaust
Lift Limit 13mm (0.510-inch) physical limit in head
Valve Followers Roller-finger follower
Lash Adjusters Hydraulic
Coolant Organic (red)

Exhaust Manifold Short-tube, S44100 stainless-steel Tri-Y tubular headers; 10mm mounting studs w/prevailing torque nuts
Intake Manifold Constant cross section, long-runner single-plane (single-scroll); molded composite w/upper section colored; front throttle body mount
Throttle Body Single-blade, 80mm, e-throttle
Engine Management Software Copperhead
Mass Air Meter 86mm, digital
Oxygen Sensors Universal Exhaust Gas
Knock Sensors Two, in block valley
Ignition Timing Crank trigger, rear of crankshaft
Ignition Coil-on plug
Spark Plug NGK Iridium
Firing Order 1 5 4 8 6 3 7 2
Cylinder Numbering

Right bank: 1, 2, 3, 4
Left bank: 5, 6, 7, 8
Fuel System Port fuel injection, returnless
Fuel Injectors 32.8-lb/hr
Fuel Pressure 55 psi
Fuel Requirement 87 octane minimum, 91 octane best/rated power

Enjoy

Greg

RyanPerrella

Greg,

Good lookup here

I came across the article recently too but i do all my internet reading on an iphone app called instapaper it just takes all the text and eliminates all the flash. But unfortunately this damn article is spread across like 15 pages. Is there a single page version of the story im missing?

I wanna read it but i dont wanna save 15 different pages to read the article....

I came across this because i was comparing V8 engine firing orders and looking for patterns. I found some interesting data, a few patterns emerged.

I was looking at Chevy LS engines, the 5.0L Lexus, 5.0L Coyote BMW S62 and N(whatever the new M3 engine code is) and our 928 and found the following patterns. I tried to find the firing order of the 6.2L exclusive to the Merc SLS but finding a firing order for that thing had been impossible. Sometimes these patterns must be seen over multiple revolutions to get it but in short i found the following.

V8's fire on a bank by bank order in the area of 2 1 1 2 1 1 What that means is that the left bank fires consecutive like cylinder 2 cylinder 1 then the opposite bank once then the opposite once then the opposite twice then once and once.

I also found a pattern in outer cylinders and inner cylinders. Outer on the 928 would be cylinders 1 4 5 8 and inner cylinders would be 2 3 6 7. The pattern that here is that inner inner inner inner outer outer outer outer of I I I I O O O O

I found this fascinating because ive had some people I respect tell me that the 928 firing order is unique, and unlike any other V8. This came up because Im designing something and wanted to see if this odd bank firing was unique or not. The fact that cylinders fire consecutively on each bank and that the firing is NEVER Left right left right. Flat plane cranks are likely different but I wasnt looking at Ferrari's here as there not comparable.

Now i havent noticed patterns between left and right banks and inner and outer cylinders, perhaps there is a pattern there too but I havent spent the time to figure it out. The patterns I do mention however come about because opposing cylinders can cancel out vibrations and flat 4's and 6's and 90 degree V8's are the smoothest there are.

Im rambling here, but I wanted to post this and figured this thread on a Ford engine was just as good as any other thread to mention this because i used this new Coyote engine in my data and mapping.

I dont know how else to end this than simply.... THOUGHTS on the inner outer cylinder pattern and the left to right bank pattern?

RyanPerrella

I also noticed that ideally with 4 2 1 headers that ideally having non consecutive cylinders linked is ideal.

Now depending on different engines the arrangement may swap side to side but i noticed that an ideal layout for 4 2 1 headers is to have cylinders 1-2 paired and 3-4 paired and on the other side have 5 and 7 paired and 6 and 8 paired. Or vise versa bank to bank depending on which engine were talking about. In short the header from one side would look different than the header on the opposite bank. If they are mirrored then one side's exhaust scavenging is compromised.

on a merge collector this is a non issue because if they are all equal length there is no difference.

Had anyone else also noticed the same pattern? I wish i could diagram it but not sure how i can do that.

slate blue

Ryan, in regard to the pairing of the exhaust, that is the exact pairing I currently have.

You can see it here.

https://rennlist.com/forums/928-foru...r-model-2.html

I am going to further investigate a different pairings on the RHS i.e 1-4, 2-3, it is harder to make that fit though.

In the article they do talk about various factors affecting the linking up of various pipes. Anyway lots to digest in that article.

Greg

Rick Carter

How the cylinders are numbered has to be known to compare firing order the 928 and Ford small block number the cylinders the same way (see picture below for 928 cylinder numbering and firing order) but the Ford small firing order is 1 5 4 2 6 3 7 8 . SBC numbers the cylinders differently, even left, odd right looking from the front of the block, firing order is 1 8 4 3 6 5 7 2

James Bailey

nothing special about the 928 firing order and the V-8 design is NOT a smooth engine....straight 6 is far better One need only look at the big crank counter weights to understand how much it wants to shake. My 2.6 liter 911 boxer six ran a NONE COUNTER weighted crank spun up to 8,500 RPM no problem HAD SOME ISSUES ABOVE THAT !

Mark SF

"The patterns I do mention however come about because opposing cylinders can cancel out vibrations and flat 4's and 6's and 90 degree V8's are the smoothest there are. "

The smoothest engine is a straight 6, or multiples thereof (V12), as it is the only engine with perfect primary and secondary balance - the front half and rear half of an I6 mirror each other perfectly.

A flat six would also be perfect if it were not for the fact that you cannot connect the opposing cylinders to the same points on the crank, so there is some vibration induced by the offset weights of the con rods, and some torsion of the crankshaft. As soon as you start to incline the cylinders of an I6 to make a V6 or F6 the perfect balance is lost.

RyanPerrella

Rick,

YEs, I digested all that information, Chevy numbers their cylinders differently

BMW is the same, Ford is the same, Lexus is the same, i forget, but yes thats the first thing you do when making this comparison.

jpitman2

From some diagrams I did there is NO way to have a 2 plane crank V8 avoid 2 adjacent cylinders firing in sequence - all you can do is shuffle the pair around. The only solution AFAIK is to have asymmetric exhaust manifolds on the 2 banks, as mentioned above - one with adjacent ports paired, one with non-adjacents paired. Rover did this in the '80s with the BOP based V8 to good effect, with 4->2 cast iron manifolds, then 2->1 merges near the bell housing.
Greg B above is the first person I have heard of doing it on a 928.
jp 83 Euro S AT 53k