top of page




In an effort to reduce the price, the heat shielding material has been eliminated. Please wrap your downpipe and use a turbine housing blanket if necessary to prevent contact with hot parts. Photos on this page may show older design features. 


Diaper design features:

The main material used is an expensive Kevlar/Nomex blend that is oil and water repellent and rated to approximately 600F. This material will not burn. Over 600F it can become distorted and eventually melt, but it will not hold a flame. It is made in a rip stop weave and is very strong. The stitching is a thick, pure Kevlar thread for strength and heat resistance. It is also rated to approximately 600F and is rated for minimum break strength, and is not cheap. These are MADE IN THE USA, right here in Marion County, Ohio.

The straps used are high strength nylon. All tabs, hooks, and adjusters are stainless steel. The hooks allow for quick removal when needed and are much stronger and more heat resistant than plastic buckles.

The included absorbent padding in the diaper will hold nearly 1 qt of oil or water per linear foot and is fire resistant.

These diapers are 1g/2g specific for the same of motor mount clearance. 1g diapers have cutouts for the two block mounted and mount brackets, 2g diapers do not have those for maximum coverage. All diapers will accommodate the stock dipstick tube and stock location turbo oil drain. Switching to an AN style oil drain fitting on the pan will make it much easier to remove and attach with the diaper in place. All diapers will accommodate front left axle carrier bearing and relocated alternators. Moroso pan diapers will also accommodate the additional turbo drain fitting those include. Openings in diaper for oil lines or dipstick tube have now been changed to button hole slits. In the event that they are not used, the opening is far smaller for better coverage.

Diaper vs Containment Pan:

  • An engine diaper protects the sides of the engine as well as the underside, up to within 1 inch of the deck surface per NHRA rules, preventing parts/oil from going over the sides of the pan.

  • The diaper contains oil even at high speed. With a pan, oil can be blown over the pan and under the tires.

  • A well fitted diaper doesn't restrict access to other items under the car.

  • A Diaper will contain all fluids in the bottom for easy removal. Removing a pan filled with fluids can end in an oil shower.


SST Diaper vs other diapers:

  • Custom diapers can be made for 550+ by custom diaper shops, but they will require a pattern. Which means you'll be doing all of the hard work, and still paying full price.

  • FWD diapers are available from 400 up that seem like a good start, but still have fitment issues with DSMs. These also do not cover the sides of the block, only the bottom, like a fabric pan.

  • Generic 4 cylinder diapers can be had for ~250, but they are very generic and will not fit a DSM well. Most people roll the sides down into the sump leaving the block uncovered and missing out on the main benefit of a diaper.

  • Generic V8 diapers can be had even cheaper, but will fit even worse.

  • Designed to fit 4g63 exactly. Clears dipstick tube, oil drain tube, motor mounts, axle carrier bearing, and relocated alternators and bolts right on.

  • Designed to work with turbos mounted close to the block (stock location), and down pipes running under the pan (like stock). Heat shielding has been added in those areas, which is rated to 1800 degrees F.

  • Designed to clear the AWD carrier bearing and sit inside axle for maximum containment. If the car is not using a relocated alternator, there is a flap of material there to cover the opening, for maximum containment.


The front side of the diaper is captured by the dipstick tube and oil drain, so some tools would be required to remove the front side. The rear side however is easily dropped down to access the oil pan drain plug. Simply unhook the rear two straps and slide the rear panel down between block and axle.

The material used in the construction of the diaper is oil/water repellent. Remove and discard the absorbent padding, and hose out the diaper with something like Simple Green.



While we have gone to great lengths to ensure a long life expectancy, it's ultimately up to the end user to be sure the diaper will not be damaged by hot parts, sharp edges, or parts rubbing against the diaper. Make sure your wastegate dump tube is not pointed at the diaper.

Do not over tighten the straps and put undue stress on the diaper. It only needs to be tight enough to ensure the hooks will not become detached in normal operation.

Due to the nature of the use of these diapers we can not offer any warranty. But in the event of a failure of any kind please contact us. We want you to be happy with your purchase, and will work with you on repair or replacement. With diapers in service for ~3 years I have not heard of any failures. If you have any issue, melt a strap, etc, or have a good containment result after an engine failure, please send an email, I'd love to hear about it.

1g & 2g DSM diapers are $395.00 

Moroso Pan diapers are $445.00


To order, or ask any questions:

bottom of page