I am in need of blueprint specs for a 4G63. preferably the new engine but I will take what I get. Specifically, rod and piston weights, deck height, combustion chamber CC's, etc., etc. These are specs for a stock motor.

 

hrrrmmm......this isnt a small block chevy the 4g63 you know, what are you trying to accomplish?

 

Here are some specs for you for a stock engine:

Head Gasket: .005 Standard Value
Limit = .02mm

Grinding limit on gasket & head: .02 (Combined between gasket and head)
Cylinder Head Height: 131.9-132.1mm

Valves:
Face:
Standard - Intake - 1.00
Standard - Exhaust - 1.5

Limit:
Intake - 0.5mm
Exhaust - 1.0mm

Valve Length:
Standard - Intake - 109.50mm
Standard - Exhaust - 109.70mm

Limit:
Intake - 109.00mm
Exhaust - 109.20mm

Valve Springs:

Free Height - Standard - 50.40mm
Limit - 49.4mm

Squareness - Standard - 2 deg. or less
Limit - 4 deg.

Guides: Standard - Int - 0.02-0.05, Exhaust - 0.05-0.09mm
Limit - Int 0.10, Exhaust 0.15

Seats: Standard Intake - 49.29, Exhaust 48.40
Limit Intake 49.70, Exhaust 48.90

 

Intake Valve Hole Diameter:
0.3 Oversize: 35.30-35.33
0.6: 35.60-35.63
Exhaust Valve Seat Hole Diamter:
0.3 Oversize: 33.30-33.33
0.6 Oversize: 33.60-33.63

Valve Guide Hole Diameters:
0.05 Oversize: 12.05-12.07
0.25: 12.25-12.27
0.50: 12.50-12.52

Guides pressed fit until projection is: 19.5 Standard Value

Valve Guide Length:
Intake: 45.5
Exhaust: 50.5

 

Oil Pump Gear Side Clearance:

Standard Values
Drive Gear: 0.08-0.14mm
Driven Gear: 0.06-0.12mm


Here is some stock crank info also:

Crankshaft Pin Outside Diameter ident marks:

I = 44.995-45mm
II = 44.985-44.995
III = 44.980-44.985mm

Piston Size Match to Bore Size:

Cylinder Bore Size Mark:
I = Piston Size "a"
II = Piston Size "No mark"
III = Piston Size "C"

Connecting Rod Big End Side Clearance:
Standard: 0.10-.025mm
Limit: 0.4mm

Piston Ring Side Clearance:

Standard for "No. 1": 0.03-0.07mm
"No 2": 0.02-0.06mm

Limit for "No 1" and "No. 2": 0.1mm

With the piston ring in the bore forced down with the piston, the end gap of the ring is:

Standard for No. 1: 0.20-0.30
No. 2: 0.35-0.50
Oil Ring: 0.10-0.40

Limit: No. 1 & 2: 0.8
Oil Ring: 1.0mm

Crankshaft Pin Oil Clearance:

(Plastiguage) Standard: 0.03-0.05mm
Limit: 0.1mm

 

Crankshaft Journal OD (There is a table also to match to the correct cylinders, bearings, etc..):

Ident Mark: 0 = Size: 56.994-57.00
1: 56.988-56.994
2: 56.982-56.988


Bearing Cap Bolts:

Limit: 71.1mm

Crankshaft Endplay:
Standard Value: 0.05-0.25mm
Limit: 0.40mm (If past limit replace number 3 crank bearings)

Crankshaft Journal Oil Clearing (Plasti-Guage)
Standard: 0.02-0.04mm
Limit: 0.1mm

Cylinder Block Squareness/Warpage:
Standard: 0.05mm
Limit: 0.1mm
Grinding Limit: 0.2mm

Cylinder Block Height:
290mm

Bore Cylindricalness:
Inner Diameter: 85.0mm
Within: 0.01mm or less

Boring Finish Dimension = Piston OD + (Clearance betwwen piston OD and cylinder) - 0.02mm

Clearance between piston and chamber: 0.02-0.04mm

 

Cylinder Bore: 85.0
Piston Stroke: 88.0
Compression: 8.8
Intake Valves Open (BTDC) 21 deg.
Closes (ABDC) 59 deg.
Exhaust Valves Open (BBDC) 58 deg.
Closes (ATDC) 18 deg.

Timing Belt stuff:

Tensioner rod length: 4.8-6.0
rod production length: 12
Rod pushed in (22-44lb): 1.0

Rocker Arms / Camshaft:

Camshaft cam height:
Intake 35.79-35.29
Exhaust 35.49-34.99



I think this should all be right. I can double check and look up the rest of it later but I dont even know if this is what you were looking for.

 

That's the stuff., TrinaBabe. Thanks. Any other bits are appreciated.

 

Ill see if I can post it up a better format or something

 

Nice post on the specs. bump

 

where the crap did you get all those? lol

 

maybe he took the time and physically measured everything. Wow. . . thank you for the useful info.

 

some good info

 

Does this mean it is impossible to just replace the bearings with high performance bearings if any OEM parts are still used (i.e., rod, crank) since each engine has different tolerences from manufacture?

For instance, if you catch bearing wear at first stages - copper just starting to expose on bearing surfaces - and the main and rod journals are still good, you can't just order a kit of high load journals as a replacement, you have to individually order each OEM bearing ID size for each cyl, and each main. Right?

 

It's not the bearing ID, it's the thickness of the bearing itself to obtain a specified clearance.

If you are showing copper... find out what caused the wear, and insure that is resolved before completing the rebuild

"high performance bearings" are typically just a harder bearing that can withstand a bit more abuse... however these are of a standard thickness, and you cannot obtain as fine a clearance tolerance as with the stock bearings. So, there is a trade-off to using "high performance" bearings. Most builders stock 1 standard size of bearing, and ignore the fact that the clearances are slightly out of factory spec.

Just for a comparison:

Toyota uses 5 different bearing sizes for each the crankshaft journals, and 4 different sizes for the rods (as well as .5 os bearings). Meaning that there can be thousands of different combinations, and to have the right bearings on hand for a rebuild, you need to stock:
24 narrow Main journal bearings
6 wide journal bearings
20 rod bearings

I used to keep these on hand for the 3S-GE and the 4A-GE, and replinish my stock after each rebuild. at $3-$5 each, for each style engine I had about $200 worth of bearings in stock, just to have the right item on hand when I needed it.