Does anybody make them?
I have been thinking it might be a good idea to add one to my car.
Cracking an iron at 100+ MPH scares the hell out of me!

 

i think a undertray may be more beneficial, as a nappy is only designed to catch broken rods and crank parts in a piston engine,
where a undertray could be designed to catch random spraying oil an water .

I too would like to know what absorbent matt to use and how to fix it to the tray , sounds like a good idea

 

you need to make them custom.

 

I'm now in the market for one as well. Either a full undertray, a diaper, or a combination of the two. Another pro of the undertray is increased aerodynamic efficiency.

 

Guess that will be my Winter project. Design a tray out of aluminum that has deep wells in it to hold liquid.
It can fasten to the stock undertray holes in the front. Just need to figure out how to encase the whole drivetrain and fasten it in the back.

 

Pretty sure the NHRA rulebook has specs for containment trays.

Bruce, thought I saw your car for sale in the classifieds. Glad you're keeping it if it was.

 

Yup. Per 2011 Rule Book.

1:8 LOWER ENGINE CONTAINMENT DEVICE
In classes where specified, must utilize an NHRA-accepted lower
engine oil-retention device. SFI Spec 7.1 or 7.2 Lower Engine
Containment Device permitted. A properly fitting lower engine
ballistic/restraint device mandatory. The NHRA Technical staff can
accept or reject any device. Any device that fails to perform as
required must be replaced or repaired to the satisfaction of the
Technical staff prior to any furthur runs. When used, an SFI Spec
7.1 or 7.2 Lower Engine Containment Device must cover the sides
of the block and pan up to within one inch of the head mating
surface and extend to within 1 1/2 inches of the front and rear of the
cylinder case area. SFI Spec 7.1 devices must be
updated/recertified by the original manufacturer at one-year
intervals. In classes where specified, a belly pan may be used in
lieu of a device attached to the engine. The belly pan must extend
from framerail to framerail and extend forward of the harmonic
balancer and to the rear of the engine block and must incorporate a
minimum 2-inch-high lip on all sides unless specified in Class
Requirements. Minimum number of slots or holes in the walls to
clear frame, steering, or lines permitted. A nonflammable, oilabsorbent
liner mandatory inside of retention device.

 

Nobody wants to pay even a fraction of what it is worth. I won't give it away.

 

http://shop.holcombmotorsports.com/p...&categoryId=69

Check this out Beef. It still doesnt really say what its made out of. We have some oil/water absorbent pads here at work that look very similiar. I'll see if I can find out what they are made of or who makes them. I bet they are much less expensive than "race" diapers.

EDIT: Or check these out. We have the oil-only absorbent pads at work.

http://www.supplylinedirect.com/item...ersorbentpads/

 

yeh we got the same style pads in our oil spill kit at work, may do something with that .

And on the rule book, our ANDRA rule book only requires piston engines to need a diaper , and containment device is not needed but recommended.
Rotaries aint even on the radar for australian rule makers

 

Dude, Rotaries oiling tracks IS on Andra's radar.

 

its not a rule as of yet though but its gonna be needed anyway as it makes sense for safety sake, (dont get me started on how many guys run wastegates directly at the track too) , even our WA tech rep who races a rota gave the track a good spray a few weeks ago, hes now designing a better breather and containment for his car to be at the goldenstates soon, he skipped the opening meet becuase of not being happy with it oiling the track

 

Just happened to be re-reading Allen's thread below on oil system mods today and thought I'd bring it back to this thread. One of Allen's reasons to make all these changes was to keep the engine from losing oil if it split an iron at the dowel. Seems pretty relavent to what we're talking about here.

Saw your dyno post and your mention of Haltech engine management. Just wanted to let you know that we're one of the leading Haltech dealers in the US and have setup many Miata with various Haltech systems. We offer the basic Haltech packages as well as our own custom wiring solutions that are custom built for indivdual applications. We're enthusiasts that love to help the community and answer questions. If you have any questions, whether it involves a Haltech system, another type of engine management (we do deal in many types of systems), or general performance questions, feel free to ask.

https://www.rx7club.com/showthread.p...light=oil+mods

 

The easiest thing people can do to stop oil coming out of an engine is to run an external oiling system.
I have been doing this for the last 8 years. Basically i looked at how many rotors were oiling the track and thought 'how do i prevent this from happening with my own engine'.
I run a solid 1 piece dowel thru the top oil gallery. The rear plate is grub screwed where the dowel locates and the front plate has a long threaded plug with o-rings that stops oil getting to the dowel .
This will go along way to stopping oil from spraying out of a cracked plate. If the oil isn't there it can't be sprayed out.
Mods such as these may become mandatory in ANDRA drag racing in the not too distant future...as well as belly pans.

 

Oil mods would not have helped me.

 

nope, i certainly wouldn't focus on that top pin either because if the motor wants to twist it will. dowelling goes a bit further than that one simple area.

 

a rota oils down in so many ways, best bet is to help contain the after affect, sure prior mods to help stop the cause is good but you cant predict everything , and id hate to have a rule enforcing me on how i build my motor.

 

I am starting construction on a pan the covers half of the underside.
Making it out of old street signs and I will put absorbant material in the bottom of it.
Using the stock undertray as a template for part of it.
It's my understanding this will also help with trap speeds.

 

Used two 9$ oil pans from Wal-mart. covers from radiator to end of trans. I know you can make a nicer one but just a idea. Another thing to consider making is a shield around the front a rear dowel pin area. (i'll get some pics later) So if one of the plates cracks the oil will hit the shield first then drop strait down to the diaper. When I've cracked FC plates the oil gets squirted every where and I don't think the best diaper out there can contain it. 100psi oil pressure make a big *** mess.

Learning the laughing gas is deadly.

 

VERY good idea Chuck! I'm gonna go to Wally World! Better put my teeth in first!