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Black Diamond Replacement Valves for Evolution (84-99)

$17.83 
SKU: 20-4171
  • Black Nitroneg stems
  • One piece forged stainless steel valves impregnated with a special German process to improve wear properties and reduce friction
  • Provide resistance to corrosion and wear superior to hard chromium and electrolysis nickel plating
  • Single Groove valves
  • See Specifications Below
  • Not sure which you need, view or download the chart from the Goodson catalog

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Order No. Description Price Quantity
20-4171 Intake | 1.840" Head Dia. | 0.3100" Stem Dia. | 0.236 Tulip Rad. | 23º Tulip Angle | 4.445" OAL $17.83
20-20905 Intake | 1.990" Head Dia. | 0.3108" Stem Dia. | 0.675 Tulip Rad. | 25º Tulip Angle | 4.440" OAL $24.60
20-20910 Intake | 1.940" Head Dia. | 0.3108" Stem Dia. | 0.675 Tulip Rad. | 25º Tulip Angle | 4.440" OAL $24.60
20-20915 Intake | 1.900" Head Dia. | 0.3108" Stem Dia. | 0.675 Tulip Rad. | 25º Tulip Angle | 4.440" OAL $24.60
20-4171R Intake (Racing) | 1.900" Head Dia. | 0.3100" Stem Dia. | 0.344 Tulip Rad. | 28º Tulip Angle | 4.420" OAL $17.83
20-20900 Intake) | 2.150" Head Dia. | 0.3108" Stem Dia. | 0.550 Tulip Rad. | 24º Tulip Angle | 4.480" OAL $24.60
20-4170 Exhaust | 1.615" Head Dia. | 0.3096" Stem Dia. | 0.236 Tulip Radius | 29º Tulip Angle | 4.525" OAL $17.83
20-4170R Exhaust (Racing) | 1.630" Head Dia. | 0.3096" Stem Dia. | 0.500 Tulip Radius | 40º Tulip Angle | 4.525" OAL $17.83
20-20920 Exhaust | 1.650" Head Dia. | 0.3106" Stem Dia. | 0.750 Tulip Radius | 25º Tulip Angle | 4.515" OAL $24.60
20-20925 Exhaust | 1.610" Head Dia. | 0.3106" Stem Dia. | 0.750 Tulip Radius | 25º Tulip Angle | 4.510" OAL $24.60
20-20930 Exhaust | 1.585" Head Dia. | 0.3106" Stem Dia. | 0.750 Tulip Radius | 25º Tulip Angle | 4.505" OAL $24.60

More information

Returns

To return an item:
1. Write a brief note describing the reason for the return. Please be sure to include your name or company name or account number.

2. Return the item freight prepaid within 60 days from the invoice date. For best results, please ship return merchandise by UPS or Federal Express. Please keep your receipt because it may be necessary to track the package if it is lost in transit.

3. A 10% restocking fee applies on all returns unless the problem was the fault of Goodson. If so, the restocking charge is waived and shipping costs are reimbursed. Credits will be made to the account originally billed.

Send the completed Product Return Form along with the product to:

Goodson Shop Supplies
ATTN: RETURNS
156 Galewski Drive
Winona, MN 55987

Read our complete return policy.

Shipping

Goodson strives to ship orders the same day they are recieved. In fact, we track this on a daily basis and we are currently shipping 99.97% of orders on the same day.

We use most major carriers including FedEx, UPS, USPS and regional carrier, SpeeDee.

For more information, check out our Shipping & Delievery page.

International Sales

Goodson ships F.O.B. Winona, Minnesota, USA to most countries around the world. To find a distributor near you visit our Distributor Listing.

If there is not a distributor in your area, you can contact Goodson by phone (1-507-452-1830) or order online. Please note some items (such as Sunnen) are not available for shipping outside of the United States & Canada. If you have these items in your shopping cart, your order cannot be processed. You must remove those items from the cart to continue.