For you guys that have the RX6 kit (and those with other kits, for that matter), does it get EXTREMELY hot over your wastegate and downpipe? On a 70 degree day, if I sit in traffic or let the car idle, my air intake temps get as high as 80 degrees, even with the FMIC, and if you pop the hood the heat under there is unbelievable. The downpipe glows visibly orange, and it got so hot that it melted the Profec B vacuum lines as well as those little plastic covers that you can put over wires. It even boiled the washer fluid and made it spurt out onto my windshield! And I don't have to boost for this to happen. If you start the car and let it idle for long enough it'll get this hot. If I can ever get moving at all, everything cools down quickly again. Water temps are staying low, 88-92 or so.

The O2 sensor is reading rich at idle, 0.85 - 0.9 or so. I know, I know, it's not accurate, but I'm just saying it reads rich enough that the heat shouldn't be coming from leanness. Any ideas? I'm assuming this isn't normal.

If this keeps up, I'm going to have to get a vented hood out of true necessity! I thought one of the benefits of a single was reducing your heat!

Thanks

 

That exact thing happened with my twin turbos when my cat clogged. Please let me know what you find out because I am getting the rx6 put on next week.Good luck
Kevin

 

It does get hot, but what you are experiencing is much more extreme than I get. I recently replaced the O2 sensor because the wires melted (just the insulation) right where they come out of the sensor. But it doesn't get anywhere near glowing at idle. I was driving the car hard the other night and was hoping to see it glowing when I parked, but it was not glowing at all. Perhaps your timing is retarded or you have a really lean idle.

The super-thin downpipe makes for a lot of noise. It seems like a ceramic coating would be a good idea for noise and heat, and maybe even some header wrap on top of that for good measure.

-Max

 

I never got that hot ever on my car. My air intake temps never go above around 60 since I switched to single turbo. Of course I have the newer version of this turbo kit and the design is different so I don't know

if anything you could try using heat wrap around parts of your engine bay.

 

Thanks for the replies. I can't imagine this is normal, but I don't understand what could be wrong either. My idle is overly rich. I just bought the Bonez cat about 6 months ago, although I guess that doesn't mean it isn't clogged. The timing maps are slightly retarded at the highest numbers of the maps (I believe he capped everything off at about 17 degrees, if I'm not mistaken).

I've been adding high quality carbon fiber or aluminum wraps to everything I can, but I don't see how I can protect everything from that degree of heat. Unfortunately the wiring harness is right in this same area, and I DON'T want that harmed!!!! Seems like I need to get to the source rather than fix the symptoms, anyway. I asked about wrapping the exhaust and was told that they had seen instances where the downpipe actually melts as a result of doing that! The ceramic coating could be nice though.

Just to clarify, the super high intake temps are only when sitting still or nearly still for about more than 10 minutes.

Well, I'm still pretty perplexed on this one. Guess the cat is about the only thing I know of to check at this point. Thanks again and let me know if anyone has any other ideas.

 

Are you running an airpump? I'm not neccesarily in the camp that thinks not using an airpump automatically means cat melt down, but there are different quality of cats, just like anything else. I've heard some say Bonex cats are the best, and I've heard some say they melt quickly...

All parts on my kit are ceramic coated, and the highest I've seen is 64C intake w/no SMIC duct, no airpump w/ Random Tech hiflow cat.

 

if you have a cat with no airpump that can be the cause of your problems. I know that if you have no airpump the cat usually get caught on fire and gets super hot. When did you buy your turbo kit? I know my version allows retention of the airpump, but if you have the earlier version and have a cat then that can be the cause of your problems

 

tailhappy, did you also manage to fit the heat shield for the turbine? I remember it beign a pain in the **** to get that thing to fit, and I know a lot of people neglect to actually fit that, but that in itself can make a big difference.

 

I thought air made the cat run hotter as it fuels the fire in there? I guess the other argument is that it doesn't get hot enough and oil and crap collects on the element because it isn't hot enough to burn off. I am not sure if either argument is true. I suspect that you can run the car with a cat and no air pump without a problem, but there doesn't seem to be much information one way or the other.

-Max

 

Good thoughts guys! Unfortunately I am running the airpump, and when I had it on the lift I verified that the hose was actually still connected to the cat. And the heat shield is on there.

OK, so let's step back and look at the whole picture again. The source of this really has to be two things so far as I can tell. Either the mixture is wrong which is causing high exhaust temps, or the cat's clogged? Any way to test a cat, or do you just have to buy a new one? I hate to do that since these things are so expensive! And what does your O2 sensor read at idle? I was thinking before this whole engine/turbo swap, my idle was nearly completely lean, like less than 0.1V. Now they're hovering at high 0.8 - 0.9. This can't be that difficult...must be obvious!

Thanks again!

 

Since you have a FMIC, do you also have the fan mod switch installed and keep it on in stop and go driving.

I live in Houston and keep my fans on all the time in summer while in stop and go driving or when I plan to race. Keeps my Blitz FMIC outlet temps cool all the time plus keeps the engine bay also cooler.

I agree that it appears your cat is clogged.

 

I don't have the fan mod, but on one particular day it was raining out and I had the headlights and AC on, so the fans should have been on high as a result of that. Plus my PFC is remapped to have them come on at 92C. Everything still got superheated (but water temps were below 90).

So it sounds like the cat's the most likely culprit. I still have my old stock cat, although I think it's clogged too. Guess I could put it on to see if there's any difference.

 

What was told to me by Random Tech is that the airpump is not to cool the cat down (though with a very restrictive OEM cat, overheating may happen), but to aid in the chemical reaction that occurs inside the cat.

But in either case, running a different configuration other then stock opens up all sort of possibilities, whether stock cat/no pump, after market/no pump, etc. Like you said, no conclusive data either way.

 

Running that rich at idle could be the cause - the excess fuel is still burning in the DP, Figure out why you are getting so much fuel at IDLE and that should cure your HEAT problem.

 

Thanks maxpesce! I knew a lean condition could cause hot exhaust but I had wondered about rich doing as you described. That's why I kept throwing that out there to see if anyone would jump on it!

My maps definitely need tuning. They're just the usual safe/rich ones right now. Looks like that'll be the first thing I should check.

Thanks again for everyone's input!

 

I doubt it's your air pump. You probably don't need the heat shield as it retains heat around the downpipe/pre-cat area.

Correct, the air pump supplies air (mainly oxygen being the catalyst) to the catalytic converter and when the excess fuel hits the monolythic brick, it'll burn. So, you have cleaner emissions.

You are probably running extremely rich or your timing is off. I'd check the maps. I've leaned out a 62-1 turbo set-up such that the turbine would stop glowing (10psi-12psi runs) and I didn't have to mess with timing at all (it was spot on during idle).

The concept behind very rich conditions causing the downpipe and midpipe (or cats) to be very hot is that excess fuel (lots of it!) is getting by the turbine and igniting down the exhaust.

How does the exhaust smell during idle? Is it rich enough to make your eyes water?

J

 

Good post, J. The exhaust is stinky. I haven't gotten close enough to get it in my eyes, but it definitely smells rich. In fact, while we were messing with the datalogit one day and letting it idle for an extended period of time, it apparently fouled the O2 sensor. The sensor started reading in the 1 - 1.1V range. Never seen it do that before....

 

Pull your cat and let it run idle. If it heats up just as much as when you had the cat on then it is not the cat.