Performance Manifold, Mikuni 45 & 48 Carbs Twin Cam & Evo Strokers 4.10″

Description

This 4.10″ wide manifold has been designed to position the carb back in at a stock Harley Davidson location when using both HSR45 and HSR48 carbs on large capacity Twin Cam and Evolution engines requiring differing manifold lengths. The manifold features a enlarged internal plenum area and oversize (1.880” O.D.) spigots on the ports for mating with both stock or oversize port heads, for improved performance without any adverse effects on air flow either way.

Mikunioz manufacture this manifold in lengths 4.05″, 4.10″, 4.17″ and 4.28″ where designed for use on both Evolution stroker engines and twin Cam engines, where if using the map sensor the blank hole requires the bottom to be drilled out to open it. There is an allowance in the external outlet port lengths for shortening a longer version manifold back to a mid-available options range length to match a motor not covered by the offered lengths..

The oval inlet port is designed for mating with Mikuni HS42/062-45 Rubber Flange for HSR45 carbs or the HS42/062-48 flange for 48mm carbs. This will position the HSR so as not to protrude out any further than stock with the benefit of better carburetor heat isolation and far more secure mounting using a hose clamp.

It is always recommended to replace your manifold to head O-ring band seals when fitting a new manifold.  You can use your stock plates with this manifold but will need the narrower rubber seals to suit the 1.880″ spigots. Sorry not available through Mikunioz.

This 410 (4.10″) manifold directly suits:  Applications shown assume stock case deck height and stock to moderate-cut cylinder head deck thickness.

1999-2005 TC Heads, Engine Size 88″ – 95″ – 103″ – 107″, Cyl Length: 4.937″

Stock cylinder length for EV Big Twin = 5.550″
Stock cylinder length for EV Sportster = 4.650″                                                                                                                                Stock cylinder length for TC 1999-2005 = 4.937″                                                                                                                      Stock cylinder length for TC 2006up = 4.937″

If prepared to slightly shorten the spigot lengths these will then also work with:

S&S EVO, Engine Size 113″ (4″ x 4 1/2″), Cyl Length: 4.995″, Manifold Width = 4.06″

S&S EVO, Engine Size 117″ (4 1/8″ x 4 3/8″), Cyl Length: 4.888″, Manifold Width = 4.08″

Also may suit other motors as shown in the S&S manifold chart in the pictures file and also motors from other engine building companies.

Depending on head, cylinder and or engine case decking heights plus also gasket thickness etc there can be slight variations in the port spacing where the manifold may be slightly too long. If a manifold doesn’t slip down into place, it cant be forced, you should run some tape around the two side ports for a witness line so as to keep it square, and then take a little material off one or each side. By a little I mean a little as its very surprising how much it takes to drop down into place. If you don’t have a bench mounted belt sander, wet and dry sand paper on a sheet of glass or other flat surface works well. keep test fitting so as not to go too far.