So, just started to install a new radiator and saw that it has two brass holes at the bottom, and it comes with brass nipples to install in the holes. The radiator is supposed to be for a manual transmission. Is this an A/T thing? Here's a photo of old and new.

Old and new radiator Any way to make this work?

Also, any suggestions for replacing the foam? The old foam is crumbling to dust...

 

Those fittings are for the trans cooler, it's for an automatic car. Or that company only makes one radiator that is supposed to fit the auto and the manual RX-8.

 

Nothing will leak out of those, you can just leave them open like that. Just make sure the core is the same size.

 

Awesome! Glad to know. The core is the same size, just a weird angle for the photo.

 

And for the foam, just buy the square foam at Home Depot or Lowe's and use double sided tape (or gorilla Glue gel works too) to attach to the new Radiator in the same pattern as the OEM foam.

 

Something attached to the plastic undertray to stop the foam blowing up is a good idea too

 

^ if there was a like button, I would like that post.

 

Went to Home Depot and all they had was rigid insulation foam sheets. On my way home I stopped at the local Ace hardware and found just the thing!

I'll glue it on and add some foil tape to maybe help it resist the heat from the engine bay.

Thick foam weatherstripping

 

They have that at HD and a lot of variations, you probably weren't on the aisle where they keep it. That's way big, too.

 

The HD aisle where the weatherstripping, door seals, window insulation, etc. had nothing wide enough for this application. Easy enough to cut down. Locktite glue and some metal tape and I'll be ready to install that sucker tomorrow.

 

I'd recommend removing some of that, unless you like to cook steaks in your engine bay Ruths Chris style. It's a common misconception to seal the radiator off completely. You actually want it to seal at low speed and then at higher speed to fold back and let some air pass. Blocking it like that doesn't force more air through. It backs up and forms a pressure wave at the bumper instead while stressing the undercover attachments.

 

Dang! Glad you said something. The material isn't stiff. I just thought it might melt. I'll see what I can do about loosening it up a bit

 

I was saying it for a long time and someone finally tried it, but note he didn't experiment with removing more, the combustion side of the engine generates a lot of heat too ...

https://www.rx8club.com/series-ii-af...4/#post4769098

 

He did say "went crazy with the foam" implying he had it sealed up as tight as a nuns .

On the flip side , removing all the foam is a great way to overheat your engine . The point being , "have enough but don't overdo it " . Something that can be said about just about anything

My pick is leaving it similar to oem but stopping the underfoam blowing away at speed as mentioned previously.

 

Yeah and that tape will likely just fall off with the heat. And that is exactly what I used.

 

I wonder how much pressure the AT cooler system can handle. Like, could you pipe the oil cooler loop through it? Would that even help?

 

I doubt it would help at all but I am sure it would handle the pressure fine, it's just pipe that runs in and out of the lower tank.

I have added a cooler to that circuit on a buddies 2007 AT RX-8 that sees a good deal of track use. It helped a lot, he hasn't blown any more transmissions.