Air and Fuel› Fuel Cells, Tanks and Components

Pettit

AST-SP Air Separator Tank

$189.93

SKU: AST - SP Swirl Pot-1

In Stock
In Stock
Ships by Sep 13
Free Shipping over $200
$100 Minimum Order
30 Days Return
INSTALL DIFFICULTY
DIY PRO SHOP

Easy — 1–2 hours

Overview

The Pettit Racing AST-SP is an Air Separator Tank that incorporates swirl pot action. The inlet tube's position creates a swirling action, enhancing heat transfer.
Show original supplier description
The Pettit Racing Air Separator Tank (AST-SP) is engineered to enhance cooling system efficiency for the Mazda RX-7 FD (1992-2002). This redesigned component integrates swirl pot functionality, which improves the removal of entrained air circulating with the coolant. By repositioning the inlet tube, the design induces a swirling motion that promotes better heat transfer, particularly under demanding conditions like racing or spirited driving. Constructed from CNC-machined 6061 T6 aluminum with a durable black textured powder coat finish, the AST-SP is TIG welded in the USA to high standards. It features a billet cap neck and hose nubs for secure connections. The unit includes a 13lb lever vent safety cap, clamps, and fasteners for installation. Beyond improving heat transfer, the AST-SP offers added protection by minimizing oxidation and the formation of rust and corrosion. This helps maintain the integrity and efficiency of the cooling system over time. The product is specifically designed for the Mazda RX-7 FD models from 1992 to 2002.
Vehicle Symptoms
  • Overheating during hard driving or track days
  • Coolant temperature spikes after shutdown
  • Frequent need to bleed air from cooling system
  • Loss of coolant without visible leaks
  • Inconsistent heater performance due to air pockets
Relevant Conversations
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Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

Fitment

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Specifications

BrandPettit
Part NumberAST - SP Swirl Pot-1
CategoryAir and Fuel

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Returns & Fitment

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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Shipping

Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

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