OK THE SHORT STORY, GOT A EF 5.0 THAT I AM NOT HAPPY WITH THE PERFORMANCE, IN MY BOOK, IT SHOULD CRACK A LOT HARDER THAN WHAT IT DOES, SOMETHING IS HOLDING IT BACK, WHAT IS IT?

THE LONG STORY, WHATS BEEN DONE TO THE DONK, AS FOLLOWS:

BORE AND HONE +30 THOU
2X FULL RECO HEADS (PORTED EXHAUST AND INLET)
NEW VALVES X 16
NEW OIL PUMP
LINISH CRANK
NEW ROLLMASTER TIMING GEARS
FULL GASKET SET
R&R ROD
PISTONS AND RINGS +30THOU
MAINS BIGENDS
R&R CAM BEARING
ACID CLEANED
200KW CROW CAM, ROLLER
CROW PUSH RODS
GENIE EXTRACTORS
HIGH FLOW CATS X 2
TWIN ALL THE WAY 2 1/4 INCH PIPES
2 STRAIGHT THROUGH 2 1/2 REDBACK MUFFLERS
INLET AIR PORT IS TE SERIES WITH K&N

NOW NOT SURE ABOUT IF ANY COMPUTER TWEEKS, AS ALL THIS WAS DONE BY PREVIOUS OWNER, WITH RECIEPTS, AND DOUBLE CHECKED BY PULLING THE ENGINE DOWN AND CHECKING, AND AS PER SALE AGREEMENT, IF IT AINT GOT WHAT YOUR RECIEPTS SAY ITS GOT MONEY BACK GARANTEE, SIGN HERE!
EVERYTHING WAS THERE AND IN MINT CONDITION!

CROW CAM IS PART NUMBER 629200

INLET IS STOCK EF 5.0
EVERYONE SAYS THAT IT IS THE DRAW BACK, HOLDING BACK FROM GOING HARD,
FRIEND SAYS HE CAN HAVE IT MACHINED AND IT WILL GO LIKE THE CLAPPERS? ANYONE HEARD OF THIS? CAUSE I AINT BUT OPEN TO TRUTH OR BULL s**t!
ANYONE KNOW WHAT I CAN DO TO GET IT GOING TO ITS POTENTIAL?
SOMETHINGS MISSING, I AM JUST NOT SURE WITH INJECTED MOTORS, BUT IT GETS OFF THE LINE WITH PLENTY OF URGE, BUT IS VERY FLAT IN THE TOURQUE CURVE, FLAT MID RANGE, DEAD TOP END.
ANY HELP MUCH APPRECIATED

Start from the beginning... and where the restrictions will most likely be..

Air Filter (stocky or K&N??)
MAF - stocky is like 55mm from memory... try for something bigger. I have a 75mm Chrome bullet Pro M Maf.
Throttle body - Another big restriction in stock form. You will need to machine out the opening on the manifold and the EGR to go bigger - but its worth it. I have a 65mm SVO Throttle body, but want to get a 75mm sometime soon.

OK... now we are up to the manifold.. You can either extrude hone it, or go aftermarket.

Heads - you say they have already been done, but E7's are pretty crap anyways.

Injectors... most likely you have 19's... Depending on what you want, go 24's or higher.

I could keep going, but its like 4:30am, and my brain isnt working too well. But that should give you something to think about (the car- not me being brain dead)

If you're serious, you'll dump the heads and intake for aftermarket items.

The heads, intake, throttle body and MAF would be big parts of your problem. What gears are you running? It's no good running a motor that can't get on cam due to tall gearing.
The E7 head is athsmatic at best. GT40P's are better but most performance rebuilds go for aluminium heads.
The HO manifold is woefully athsmatic - long runners and small ports don't help an engine built to rev. An AU/Explorer manifold will wake it up higher in the rev range but will trade off some torque. Same goes with most aftermarket manifolds.
The 65mm throttle body is a good general purpose unit for the 5.0 with revs under 6250. An AU one can be modified (the E series TPS actually) but you can get good ones from Professional products, MAC, Edelbrock, BBK, Ford racing and Accufab.
If you are still using the standard MAF - you are throwing a lot of your airflow out the window. An AU unit retrofitted with the E series electronics will be a cheap option (although it will run lean so check A/F ratios) but the best way is to go for a 70mm or 75mm Pro-M, Grannatelli or C&L meter.
Shane

Im all ears!

Hello XR8CHICK, long time no hear, hows the beast? Still in the club?

sounds like the top end fuel delivery is my dramas, everyone has done something different, with different results, i want a result that works, but still drivable and not to stupid on the fuel, and wont blow the budget out the window,
So an au explorer manifold the go is it? Same as EL series 2 are they not?
Just spent 6 years with an XR6 EF2 so the V8 game is a learning process for me, but at least the hard yards were done on my new baby, it just feels like a flat curve through the range, an increase in the mid and top, i will be happy as larry, it is very instant off the line, instand bag the tyres at will, then its all over, strange for an 8, improvment is a must LOL, im watching with interest!

regs from John....johnsxr6

Spot on mate

Just put it on the bottle, sorry but i am in love with the bottle
Lol