Store wide fall 🍁 savings!

  • Expert Support 7 Days a Week

  • Unmatched Quality & Experience

🔥 Fall Sale — deals across diesel, truck, UTV and audio

SKU: 07-s-001 (premier) (drop)

Hamilton 12-valve Cummins Heavy Duty Conical Springs

Regular price $642.00
Shipping calculated at checkout.


Confirm vehicle fitment

Confirm fitment before ordering. Match the year, make, model, trim, engine, drivetrain and selected options shown on this page. If any detail is unclear, search your exact vehicle or contact us before checkout.

Shipping expectations

Availability and processing time can vary by manufacturer. Available shipping choices and charges appear at checkout. Tracking is emailed after shipment. Oversized, special-order and supplier-shipped items can require additional processing time.

Returns and cancellations

Please review eligibility before purchase. Installed, used, electronic, custom, special-order and clearance items may have return restrictions. Contact us promptly if you need to change or cancel an order.

What’s included

The product description and selected variant determine what is included. Items shown in lifestyle or installation photos are not included unless they are specifically listed in the description.

Before you add to cart ✓ Confirm year, make, model, trim and engine ✓ Check the selected variant and what’s included ✓ Review availability, shipping and return eligibility

Buy with confidence

Verify fitment, selected options, availability and included components before checkout. Secure payment options and order confirmation are provided at checkout.

Description

Fits: 89-98 12v Cummins & 4bt Cummins

Valve Springs, locks, retainers

Seat Pressure 165 lbs, comes with retainers and locks.

If you are over 30lbs of boost/drive pressure or over 3500rpm with your 12valve, you are experiencing a few negative things. First, valve float, which can cause serious damage to the valvetrain. Second, intake and exhaust valves can be blown open by boost and exhaust drive pressure which allows reversion. Reversion can hurt your power potential by allowing exhaust gasses to enter the cylinder on the intake stroke. Inert gasses in the exhaust, when re-introduced into the cylinder shield the fuel particles from oxygen in the cylinder. This does a few things that negatively affect power. It increases the time delay from the start of injection to start of combustion, it decreases the maximum pressure and maximum temperature reached in the cylinder and it increases the total time needed to completely burn the available fuel. Correct valve spring pressure is a very important piece of power production. We have seen 10-12 hp increases with customers changing their 60Lb. spring to our beehives. These springs will work well up to 4,500 rpm with moderate cams and OEM size valves. If you are spinning over 4,500RPM with a healthy cam, and/or larger valves, then you need to look at going to our dual spring for safety and valve control.

*We have just updated our spring to be a Conical spring

Payment & Security

Payment methods

  • Amazon
  • American Express
  • Apple Pay
  • Discover
  • Google Pay
  • Mastercard
  • PayPal
  • Shop Pay
  • Visa

Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.

Product features

Use this section to highlight specific product features to your customers.

Product comparison grid

Add content here to explain a bit about the range of products on offer and which ones may be most suitable for your customers.

A table comparing the facets of 4 products
Facet
Product title
View details
Product title
View details
Product title
View details
Product title
View details
By
ByProduct vendorProduct vendorProduct vendorProduct vendor
Price
Price
$99.99
$99.99
$99.99
$99.99
Description
DescriptionA description of the product, including details such as build quality, materials used and reasons to purchase.A description of the product, including details such as build quality, materials used and reasons to purchase.A description of the product, including details such as build quality, materials used and reasons to purchase.A description of the product, including details such as build quality, materials used and reasons to purchase.

Our Collections

Image banner

Share information about your brand with your customers. Describe a product, make announcements, or welcome customers to your store.