Parts and component findings for the Predator Ghost 212cc engine I have.
The engine was tore down just as if a 100% complete technical inspection was done. All parts were measured and weighed. All measurable timing events of the cam and valves were measured as well. This was done because I would like to start a data base on the parts we are going to see in these engines. And yes, we are going to see them. With the current Predator 212cc engine in use today, all across the country, in karting, we have seen that these engines vary so much from one to the other. This has made it very difficult for tech officials to find a common ground by which to have a common set of standards. Yes, it would be so simple to just run them straight out of the box. Reality is, that's not happening everywhere. Because of the vast inconsistencies it has caused a lot of variations in the rule sets from one track to another and from one region to the next. This creates large problems with racers not being able to travel to a variety of different tracks, without having multiple engines "built" to multiple different standards. My hope here is to find others, be it engine builders or DIY guys who go through their engines and spec them out before actually blueprinting them. If we can start now and form a data base of numbers, it should help lessen the learning curve of what we've went through with the current Predator 212 engine that's currently in use all over America.
As we know, kart racers, dirt kart racers in particular, ARE going to gravitate toward this engine. There will be resistance, as with every engine that comes about, but for those of us who've been around karting for 40 years, we already know what's about to happen. If you like it, good. If you don't, that's ok as well. I'm NOT looking for criticism of the engine. I'm not looking for arguments. I'm simply wanting to share what technical information I have gathered off the engine I have in my possession. I'm simply hoping to collect data from those willing to share what they find. PARTICULARLY from tech officials. If we wish to discuss things that would help bring consistency to the table, for this engine, please lets do so. By that I mean things that could help alleviate the pains in the tech room.
Things such as consistent crank strokes and centerlines. With consistent strokes, the deck heights could be managed for better in the hole measurements. Consistent cam grinds. Hardened cam lobes, to prolong cam wear. The list could go on but you all get the point. Lets discuss this AS IF we were talking to Harbor Freight and not arguing amongst ourselves based on different ideals. We all know what would help, so lets all try to get on the same page here before it gets so far gone that it's a lost cause. So without boring you all any more I will share with you all, the information I've gathered. If someone sees something I missed (because I'm pretty sure I did) please say so and I'll edit it into the post.
CAM BASIC PROFILE
Intake duration @ .050" lift = 212
Intake duration @ .200" lift = 98.5*
Intake centerline of 104*
Intake Max Lift .254"
Exhaust duration @ .050" lift = 212.5*
Exhaust duration @ .200" lift = 104*
Exhaust centerline of 110*
Exhaust Max Lift .255"
COMPLETE CAM PROFILE BY LO206 STANDARD
Intake opening
.006----58* BTDC
.020----19.5* BTDC
.050----0 TDC
.100----17.5* ATDC
.150----34.5* ATDC
.200----55* ATDC
.225----68.5* ATDC
Max Lift .254"
Intake Closing
.225----38.5* BBDC
.200----26* BBDC
.175----15.5* BBDC
.150----6* BBDC
.100----11* ABDC
.050----28* ABDC
.020----46* ABDC
.006----83.5* ABDC
Exhaust opening
.006----96* BBDC
.020----58* BBDC
.050---- 38* BBDC
.100----20.5* BBDC
.150----4* BBDC
.200----16.5* ABDC
.225----30* ABDC
Max Lift .255"
Exhaust Closing
.225----72* BTDC
.200----59* BTDC
.175----48.5* BTDC
.150----39* BTDC
.100----22.5* BTDC
.050----5* BTDC
.020----12.5* ATDC
.006----52.5* ATDC
HEAD
JT94 Head
Head thickness 2.9125"
Combustion Chamber Depth .488"
Intake Seat Diameter .972" (Single 45* Angle)
Exhaust Seat Diameter .849" (Single 45* Angle)
Intake Port Horizontal Opening .906"
Intake Port Vertical Opening .916"
Intake Bowl Depth to lowest point of recessed valve guide .1.197
Exhaust Port Horizontal Opening .945"
Exhaust Port Vertical Opening .941"
Head gasket thickness .051 (Taken From inside Cylinder Hole area)
INTAKE VALVE TRAIN COMPONENTS
Intake Valve Head Diameter 27.06 MM (1.065")
Intake Valve Length 3.016"
Intake Valve Stem Diameter 5.5 MM
Intake Valve Weight 27.48 Grams
Aprox Intake Valve Margin .026"
Intake Valve Seal Flange Thickness .023"
Intake Rocker Arm Length 2.646"
Intake Rocker Arm Weight 37.72 Grams
Intake Pushrod Length 5.785"
Intake Pushrod Weight 14.69 Grams
Intake Pushrod Diameter .160"
Intake Lifter Head Diameter .928"
Intake Lifter Length 1.436"
Intake Lifter Weight 20.15 Grams
EXHAUST VALVE TRAIN COMPONENTS
Exhaust Valve Head Diameter 24.07 MM (.948")
Exhaust Valve Length 3.017"
Exhaust Valve Stem Diameter 5.4 MM
Exhaust Valve Weight 26.45 Grams
Aprox Exhaust Valve Margin .045"
No exhaust Valve Seal
Exhaust Rocker Arm length 2.6465"
Exhaust Rocker Arm Weight 37.43 Grams
Exhaust Pushrod Length 5.782"
Exhaust Pushrod Weight 14.53 Grams
Exhaust Pushrod Diameter .160"
Exhaust Lifter Head Diameter .928"
Exhaust Lifter Length 1.437"
Exhaust Lifter Weight 20.07 Grams
INTAKE VALVE SPRING AND COMPONENTS
Intake Valve Spring Length 1.210"
Intake Valve Spring Wire Diameter .098"
Intake Valve Spring O.D. .841"
Intake Valve Spring I.D. .640-.645 (Measured at each end)
Intake Valve Spring Retainer Flange Thickness .061"
Intake Valve Spring Retainer Weight 6.73 Grams
Intake Lash Cap Diameter .3135"
Intake Lash Cap Thickness .139"
Intake Lash Cap Weight 1.04 Grams
EXHAUST VALVE SPRING AND COMPONENTS
Exhaust Valve Spring Length 1.196"
Exhaust Valve Spring Wire Diameter .0985"
Exhaust Valve Spring O.D. .843"
Exhaust Valve Spring I.D. .640 - .646 (Measured at each end)
Exhaust Valve Spring Retainer Flange Thickness .0605 - .0615 (.010 from one side to the other)
Exhaust Valve Spring Retainer Weight 6.72 Grams
Exhaust Lash Cap Diameter .3135"
Exhaust Lash Cap Thickness .138"
Exhaust Lash Cap Weight 1.03 Grams
BORE 69.99 MM (2.755")
STROKE 2.171" (Stock stroke says 2.165")
CRANKSHAFT JOURNAL 1.79"
CAM LOBE BASE CIRCLE
Intake .867"
Exhaust .868"
PISTON ASSEMBLY
Piston assembly weight with rings 169.70 Grams
Piston Diameter @ bottom of piston skirt 2.755" (This don't seem like it should right but I measured it repeatedly)
Piston Length 1.8335"
Top of wrist pin hole to the top of the piston .575"
Wrist Pin Length 2.1475"
Outside Diameter of Wrist Pin .716"
Inside Diameter of wrist pin .552"
Wrist Pin Weight 44.37 Grams
Connecting Rod Weight 118.26 Grams
Top of crank journal rod hole to bottom of wrist pin hole in rod 2.362"
CARBURATOR (PZ22)
Intake Manifold Length 2.194"
Intake Manifold Flange Thickness .160
Intake Manifold I.D. @ Head Gasket Surface .08635"
Intake Manifold I.D @ Carb Gasket Surface .08635"
Venturi Horizontal Measurement @ Center of Carb Just Before Slide Area Taken From AirHorn Side .609"
Venturi Vertical Measurement Taken Just Before Slide Area From Manifold Mounting Side .765"
Venturi Horizontal Measurement Taken In Bottom Half Of Venturi Opening From Manifold Mounting Side .6125"
Vertical I.D. Measurement Of Air horn @ Transition Into Venturi 1.121"
Horizontal I.D. Measurement Of Air horn @ Transition Into Venturi 1.117"
Horizontal I.D. Of 1st Step On Manifold Side Of Carb .861"
Vertical I.D Of 1st Step On Manifold Side Of carb .861"
Idle Jet 42 (.0165")
Small Holes In Idle Jet .033"
Main Jet 85 ( .033")
Main Nozzle .102"
Emulsion Tube Length 1.046"
Emulsion Tube Diameter .196"
Emulsion Tube Pass Through Hole .111"
Small Holes In Emulsion Tube .021"
Air Pick Off Hole .097"
Venturi Idle Air Hole .109"
Venturi Idle Fuel Hole .039"
Carb Slide Cutaway .081"
Phenolic Spacer Thickness Measured @ Front And Back Mating Surfaces .294-.296
Edit to add to post.......
The valve stem tips have been reduced to 5 MM, like a non hemi. 5mm retainers will be needed.