Anyone know what size hole saw to use? I forgot to measure the hole in the old smashed hood before
I thru it away.

I can't remember off the top of my head, but I have the hole saw out in my garage. When I go out later, I'll check for you and get back to tou. Are you using the soft or hard sided flowrite? I found the soft sided one slightly smaller and the fit was better. There is not much room to work with. Jay.

I just checked. A 2 1/2 inch hole saw will give you a good fit with a tiny bit of wiggle room. You may be able to use something a 1/16th inch less, but I think you'd be cramming to get the flowrite in. The flowrite I used measures 2 11/16th inches across the total outside diameter. BTW if your not experienced at using hole cutters, like I am, you may want to practice on something first. I cut into a piece of luane plywood and when the outside portion of the cutter contacted the plywood, my 1/2 inch corded drill launched clear across the garage and into the wifes new Toyota Highlander!

Thanks, for the reply.
I have the snap in Flo rite. Your right on the 2 1/2 " hole saw. I looked it up on the SLP site.

Hopefully you didn't damage the truck too much, I had to laugh a little at the thought of seeing that
drill motor flying !

Didn't hurt the Toyota, but I thought it was going to break my wrist in half, and it scared the hell out of the dogs that where napping by the open bay door as the drill went skittering past them! Just take your time with it. BTW, I used only one small flowrite and cut the baffles behind the plenum foam. Seems to flow real good with not too much intake noise.