Engine diaper?
#1
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Car: 91 Pontiac Firebird
Engine: Killer SBC, w/ RV cam
Transmission: AutoMatic, w/ shift kit
Axle/Gears: Posi-Traction
Engine diaper?
I understand the importance of an engine diaper, but when is it required and at what speed is it required to be SFI ?
#2
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Re: Engine diaper?
best i can tell, it's 7.50, but more and more tracks are mandating them at 9.99, some even slower. some tracks offer incentives for oil retention devices. an engine diaper isn't the only option. some guys are running catch pans with kevlar lining as well.
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Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
Re: Engine diaper?
I believe those are the rules as stated above. The IHRA track I race at wants 9.99 and quicker to have some sort of oil retention device. They're not forcing you to use one but if you oil the track down without one, there's a good chance you get banned from the track for a year.
I tried installing a diaper on my car. The headers come too close to the block and there was no way I could make it fit. I need to drop a couple of header tubes to get a starter bolt out so it's really tight. I fabricated a belly pan instead that exceeds the minimum requirements. I broke a rod a few years ago at the top end of the track and the majority of the oil was in the belly pan as well as a rod cap so it did it's job.
A belly pan is lined with spill pads (pig matting) which soak up the fluids. I use a screen and duct tape to hold them in place.
I tried installing a diaper on my car. The headers come too close to the block and there was no way I could make it fit. I need to drop a couple of header tubes to get a starter bolt out so it's really tight. I fabricated a belly pan instead that exceeds the minimum requirements. I broke a rod a few years ago at the top end of the track and the majority of the oil was in the belly pan as well as a rod cap so it did it's job.
A belly pan is lined with spill pads (pig matting) which soak up the fluids. I use a screen and duct tape to hold them in place.
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Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
Re: Engine diaper?
This is what it looked like when I first made it. I've extended the back and rear section sides since then. Minimum side height requirement is 2". Those are 3". The narrower back section now has 6" sides.
This is how it looks after doing a sky high wheelie. Just some bends and scuffs but reusable after a bit of straightening. I'm going to redesign the mounts so I can make removal and installation easier. Right now I have Dzus fasteners holding it on and the rear ones are real hard to get at.
This is what the pan looked like when I broke a con rod in 2011. I used my in car camera to take these pictures while sitting down at the end of the track waiting for the deck truck to come and pick me up. All that stuff normally would have ended up all over the track. It didn't catch all the oil but it caught a lot of it.
This is how it looks after doing a sky high wheelie. Just some bends and scuffs but reusable after a bit of straightening. I'm going to redesign the mounts so I can make removal and installation easier. Right now I have Dzus fasteners holding it on and the rear ones are real hard to get at.
This is what the pan looked like when I broke a con rod in 2011. I used my in car camera to take these pictures while sitting down at the end of the track waiting for the deck truck to come and pick me up. All that stuff normally would have ended up all over the track. It didn't catch all the oil but it caught a lot of it.
#6
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Car: 91 Pontiac Firebird
Engine: Killer SBC, w/ RV cam
Transmission: AutoMatic, w/ shift kit
Axle/Gears: Posi-Traction
Re: Engine diaper?
Belly pan looks good, ordered a RCI diaper, and it's way to bulky to fit, also needs cut outs sewn in for the solid motor mounts, and the nylon tethers will soon melt since too close to the headers. Pan looks simple and cheaper than the semi custom one at DRI.($400)
#7
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Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
Re: Engine diaper?
Since I had to buy aluminum to make the pan and wasn't able to use reclaimed stuff from work or at home, cost to make my pan was somewhere around $200. Having a metal brake at work made the job a little easier.
So far according to racers, the best fitting diaper is made by DRE
So far according to racers, the best fitting diaper is made by DRE
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