I have heard tales about Indys overheating on warm days. Owners feel their sled slowing down almost as if they had sticky hyfax. It generally isn’t a huge issue with stock hoods with lots of cooling slots but it’s a problem with my RXL hoods, primarily because the original RXLs had few cooling slots-just a big radiator up front.
There are several curative remedies. One is cutting cooling holes in the back of the hood as John Curtis (NY) has done here to allow cabin heat to escape rearward.
Two is to cut holes in the back of the air box so cool air goes directly into the carbs. If you do this, use inserts with a screen to keep the cattails out of the engine. One source for these is Lonn Peterson. Thunder Products. 21676 Deep Lake Rd, Richmond, MN 56368320-597-2700. Thunder Products.com. He has a bunch of other inexpensive performance products too. 76 Deep Lake Road.
Here’s a third way just in. Tom Osier from Colo, IA came up with this smashing idea to introduce a bunch of fresh air to the engine area. He chopped a hole under the upper lip of the nose-(note mesh screen). Incoming air comes into the nose cavity and normally is trapped. With Tom’s idea, that air will flood inside. The great thing about the tom-hole is that is hidden from the eye of a casual standing person. Hurray Tom
A fourth way is to coat your pipes with Swain Tech’s White Lightning. It’s a permanent ceramic thermal barrier coating .015” +/- thick. It controls radiated heat (power) by up to 50%. Coated exhausts drop radiant temperatures by 30-50%. (In the case of an Indy with an RXL hood, the temp drops by a hundred of degrees-which is huge). It contains heat inside the exhausts to make more power by increasing exhaust velocity and improve scavenging. The power gain isn’t huge but racing with your friends will prove out the increase. www.swaintech.com. 585-889-2790. Scottsville, NY 14546