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Vanguard V twin

Billet vanguard cylinder heads IN STOCK

$1,660.00

Order 6 pairs for 20% discount. Discount refunded after purchase.

The only billet Briggs vanguard cylinder heads on the market. We were the very first to make billet vanguard cylinder heads back in 2018 and these are our latest and best version. These heads were based on oem design that was altered for racing. Large valves, better shaped/ deeper chamber, raised/ larger ports, proper short turn radius, added material under the seats and added material for the guides as well. This is our version 2.0, these heads now have a revised port and dual spark plug capability if desired for our aircraft clients. These heads were built for using computer engine software specs. Here are the specs:

1.41 intake valve

1.20 exhaust valve

25cc optimized chamber shape

1.250 intake port id

1.050 exhaust port id

stainless valves

bronze guides

.500 lift single springs with steel retainers

Reccomended spark plug: 1275 CR8E NGK

These heads use the same intake and exhaust flange pattern as oem heads. .040’’ was added to the chamber vs oem specs so it can be milled if needed. We run .550 lift on our engines with these heads and still have .125 piston to valve clearance unmilled. If you mill the heads .040’’ the stock intake can be used. They cannot be used on 12.5-16hp (model 29-30) blocks. Stock stamped steel (recent dimple model) rockers can be used. Tall valve covers required.

Out of the box these flow:

127 cfm @.500 lift intake . to compare a stock head flows 81 cfm

88 cfm @.500 lift exhaust .

We ported a set of heads on our model 35 shop mower engine:

140 cfm intake— supports 70 hp

110 cfm exhaust— supports 70 hp

These heads now have a revised port design. Previous billet head flow:

Lift Intake Exhaust cfm

.100 41 38

.150 60 54

.200 73 69

.250 88 80

.300 100 85

.350 110 86

.400 116 87

.450 119 88

.500 122 88

.550 124 90 **

**springs arent designed to run .550 lift. For informational purposes only

Lift Intake Exhaust cfm

.100 48 42

.150 64 57

.200 78 72

.250 94 85

.300 106 94

.350 114 97

.400 117 101

.450 121 105

.500 127 110

.550 130 113 **

**springs arent designed to run .550 lift. For informational purposes only

-lash caps are required

- as good as these ports are out of the box as stated above more gains can be made by professional porting. (we dont offer that service)

-these are generic heads and should not be treated as a bolt on part. Every head should be blueprinted for each specific engine. ( spring shimming , chamber shrouding, ports etc)

-The current batch of heads have a satin finish, not shiney

-shim springs .060’’ from max lift

-7500 max rpm with the included springs. purchase beehive springs for 10 000 rpm capability

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