Vanguard engine build Specs

Connecting rod torque for our rods is 20 foot pounds (not arc)
Engine pan 150 inch pounds
We torque our cylinder heads on our race engines to 200-220 inch pounds with studs
Flywheel torque 125 foot pounds
Valve lash .005’’
Ignition timing 30-32deg Before top dead center is a good place to start on gas for a race engine.
Coil air gap should be .050’’ for an ARC flywheel
We run .001’’ of cylinder to piston clearance per inch of piston diameter. Example a 3.000’’ piston has a 3.003’’ bore diameter
Always use torque plates when boring and engine
Valve springs should be shimmed to coil bind .060’’ further than max lift. example: running .500 valve lift springs should coil bind at .560’’ lift.
When you clearance a block make sure you have min .050’’ clearance between all moving parts (cam, crank, rods , retainers to guide etc)
Always run min .100’’ piston to valve clearance
Rod bearing to crank should be .002’’ . This can vary though we are running .004 on our engines currently with thicker oil and more oil pressure.
Crank side clearance should be .005-.010’’ (horizontal engines)
High lift cams require large diameter lifters to avoid flattening a cam
We use mls head gaskets on all our race engines. No need for copper
Horizontal race engines have an oil puking problem. To solve this block off the block vent between the cylinders if there is one (model 29-35) , then run a 1/2 inch diameter vent line from each valve cover to a baffled/vented catch can. See our photos
Stock head flow: - Model 30-35 67 cfm @.450’’ - Model 38 81 cfm @.450’’ Our ported model 38 heads with 33.8 intake valves flow 110 cfm.
-67 cfm can support max 30hp
-81 cfm can support max 37hp
-110 cfm can support max 53hp (ported 33.8mm cast heads)
-125 cfm can support max 63hp (non ported billet 1.41-1.2 heads)
-140 cfm can support max 70hp (ported billet 1.41-1.2 heads)

General Small Block Vanguard Specs

Model 29-30 vanguard oem bore is 2.677 model 35 is 2.835 model 38 is 2.972
Each model series has its own cylinder head casting but they are all interchangeable. Model 29-35 have the same valve size. Model 38 has larger valves (31mm-27.5), the chamber size goes as follows: model 29 (closed chamber) 16cc (not 100% sure going off memory) model 30 20cc and model 35-38 is 25cc. The model 38 head has a much better intake port .
Model 29-30 run a 2.6 stroke crank. Our billet pistons are not compatible with this stroke. Model 35-38s run a 2.75 stroke crank.
Model 29-30 engines have the same rod length as the 35-38s but have a taller compression height on their pistons. Their pistons also have a “hemi’’ sphere shape as a dish vs the 35-38s which have a square edge dish on their pistons
Model 38 engines do not have a block vent in between the cylinders, they vent through the valve covers.
Vertical engines have a thicker pan which means they use a longer journal crank. With some machining vertical cranks can be used in horizontal engines but not the other way around. There are different model cranks as well, the biggest difference between them is the block journal. All model 38s have a large journal crank. Model 35s can have large and small journal and as far as model 29-30s we don’t know (we don’t mess with those engines.) The block casting is different for each appropriate crank journal large and small.
Model 29-30 blocks have a lighter smaller block casting. It has less aluminum even if physically it is the same as the others.
Some model 29 engines have desirable large diameter lifters (.970)
There were many rockers that were used throughout the years, 8mm shaft, 6mm stud steel and aluminum. 8mm steel shaft mount rockers are garbage throw those away. 8mm shaft mount aluminum rockers are really good. There are a couple model 6mm stud mount steel rockers, dimple and non dimple. The dimple are on all engines manufactured today and are really good. They will hold up to our single spring kit (non beehive) to 7-7500 rpm approx. Our roller rockers are compatible with 6mm stud mount heads.

General Big Block Specs

Billet Big block Billet head information below

The following measurements may vary slightly, always blueprint your heads by an experienced engine builder before assembling.

We measure the oem combustion chamber to 42cc

These billet heads have a 38cc combustion chamber.

Our billet dished pistons have a 10cc dish and our milled billet pistons have a 3.5cc dish.

Here are some examples of possible compression ratios using a calculator, our billet heads and our billet pistons.

Stock heads, stock length rods, .050 gasket, 10cc dish pistons : 8.5:1

Billet heads, 5.490 rods , .050 gasket, 10cc dish piston: 10:1

Billet heads, 5.555 rods, .050 gasket, 3.5cc dish piston: 11.2:1

Billet heads, 5.555 rods, .020 gasket, 3.5cc dish piston: 12.2:1

Our billet heads flow @28’’:

Intake Exhaust

.100’’ 48 cfm 44 cfm

.150’’ 71 cfm 64 cfm

.200’’ 86 cfm 83 cfm

.250’’ 107 cfm 98 cfm

.300’’ 122 cfm 115 cfm

.350’’ 142 cfm 127 cfm

.400’’ 149 cfm 139 cfm

.450’’ 155 cfm 147 cfm

.500’’ 164 cfm 155 cfm

The valves billet heads have three locking grooves. Never use the bottom groove (closest to the valve face). The middle groove is the recommended groove to use. The middle groove allows for .510 clearance from the valve guide to the retainer. The middle groove has an installed height of 1.380, the same as our small block vanguards. This is perfect for .450 valve lift. The top groove (furthest from the valve face) allows for .100 more retainer to guide clearance, it also allows for a 1.480 install height. This allows for more lift, it will also however reduce spring pressure. The distance from the valve face to the deck surface is .350’’ (can vary slightly) which is the same as a stock head. If you run milled stock heads chances are you can mill these too to match what you have.

Here are the specs of the valve springs that come standard with the heads:

65 seat pounds @ 1.380 install height

130 pounds @ .500 lift (.800 height)

These heads have 7mm stem valves, they are larger and heavier than stock, more pressure is required than stock heads. These springs on our small blocks are good for 7500 rpm depending on the valve train setup. These billet heads are designed for 5500 rpm

Standard Big Block general info below

Stock heads, stock length rods, .050 gasket, 10cc dish pistons : 8.5:1

Stock heads, 5.490 length rods, .050 gasket, 10cc dish pistons : 9.7:1

Stock heads, 5.555 length rods, .050 gasket, 3.5cc dish pistons : 10.8:1

Stock heads, 5.555 length rods, .020 gasket, 3.5cc dish pistons : 11.7:1

On our flow bench stock heads flow @28’’ :

Intake Exhaust

.100- 39 cfm 37 cfm

.150- 60 cfm 57 cfm

.200- 77 cfm 72 cfm

.250- 86 cfm 78 cfm

.300- 93 cfm 80 cfm

.350- 97 cfm 82 cfm

.400- 100 cfm 84 cfm

.450- 103 cfm 86 cfm

.500- 106 cfm 88 cfm

Our billet heads flow @28’’:

Intake Exhaust

.100’’ 48 cfm 44 cfm

.150’’ 71 cfm 64 cfm

.200’’ 86 cfm 83 cfm

.250’’ 107 cfm 98 cfm

.300’’ 122 cfm 115 cfm

.350’’ 142 cfm 127 cfm

.400’’ 149 cfm 139 cfm

.450’’ 155 cfm 147 cfm

.500’’ 164 cfm 155 cfm