Okay so Im having problems with my exhaust system>> specifically with it putting out too much heat. My current set up from the block back is stock headers into Crawford high flows and then into a Stillen catback.
I thought the excess heat could be due to a leak in one of the connections, either between header and cat or catback and cat, but when I turned the car on and revved there was no heat and/or pressure coming out at any of the joints.
However, after any decent length drive, Id say anything more than 5-10 miles, when I exit my car I can smell something burning. I thought it was my zero gauge power line, but the fuse on it never blew, and when I jacked my car up and inspected the zero gauge inch by inch it was still intact. Also, when I look under the car IMMEDIATELY after shutting the car off after a 5-10 mile or more drive I car visibly SEE heat under the car. If you dont know what I mean by seeing heat, its like waves in the air, like you see at the back end of a jet by the engine, and its concentrated around the cats. Also, my center console plastics, the ones around my shifter all the way down to the one with the two center cupholders, all heat up a lot while the car is driving, but all the other panels stay cool, even in the sun.

What adds more complication to this is that I just had a major transmission problem in that area of my car that actually involved my driveshaft snapping in two and my ebrake wires melting. Nissan covered it under warranty but they told me they thought it was caused by excessive heat coming from my exhaust system. Originally, I thought they were full of it, but now more and more things are making me think that they could have been right.

Anyone ever heard of ANYTHING like this before?? Im afraid of snapping another driveshaft or melting anything else under my car so I wanna find out what the problem is and get it fixed asap.

 

Your car may be running excessively lean, I can tell my car puts out more heat than before, but that is because I have headers and no heat shields. Before I had headers, when I just had the borla exhaust on, I never noticed any difference in heat output. Are there any heat shields on the cats?

 

First, if you suspect any problem whatsoever with a Crawford product, CALL DOUG and ask before you do anything! He knows his, and most others', products better than the vast majority of mod dealers/suppliers.

To protect his good name, Doug has replaced several sets of headers and cats, and plenums over the last 6 mo. or so, even though there wasn't anything wrong with his products. For example, while just about all those complaining about his cats with the Nismo cat-back had a defective NISMO, most folks' knee jerk reaction was that the Crawfords were the problem (after all, we all KNOW Nissan would NEVER screw up, right, guys? ), Doug went ahead and replaced the cats of everyone who griped, even when there was no evidence whatsoever that HIS product was the problem.

Make no mistake about it, Crawford's and Doug don't claim to be perfect, and if you DO have a fitment problem with your cats due to a defect in the cats, they'll make it right: period. Again, call Doug and ask.

Second, do NOT automatically assume that heat shields are needed for Crawford headers and/or cats. For most people, it's a waste of money at best, and at worst, it may even cause problems. If you are running the type of N/A setup for which all Crawford products are specifically designed, you may experience slightly more heat (I've got the entire Crawford product line on my car, along w/a Borla TD, and all I experienced was an increase in the temp of the hood if you feel of it immediately after turning the car off). I had no discernible increase in water temp whatsoever, and the hood is still MUCH cooler than it gets just sitting in the sun on a hot day.

As for the potential problems of heat coating, one customer recently had Doug send his headers off to be heat shield coated, and after the coating company (I won't mention their name) sent the headers to the customer, a call to Doug shortly followed complaining that the headers leaked/wouldn't fit. Doug had them shipped back to him so he could fix the "problem," and when they arrived, it quickly became apparent that the problem was that the bozos at the heat coating business had coated the freakin' flanges of the headers with the rough, grainy textured coating. I know next to nothing about these cars compared to many folks (a fact which Doug, Adam and Randy w/Crawford's would quickly confirm ), and that's why I'm a member of this forum--to learn, but even I was able to figure out the problem after looking at the headers for about two seconds.

In any event, good luck w/the prob., and let us know what happened.

 

yeah Im way ahead of you
I called up Crawford the same day as I posted up this thread. I didnt ask who I spoke with, but it might have been doug. He did tell me though that it was the strangest story he has ever heard.

To wrap up the phone call in the least amount of words-
things that I had been suspecting and the call with crawford confirmed:
-my driveshaft snapping could have been due to a faultly driveshaft from the factory
-Nissan techs were blaming aftermarket parts to cover their own @ss.
-carbon fiber (the driveshaft) is cooked in 2000 degree temp so I doubt exhaust heat would cause it to crack

things I learned from the call:
-even if the cats were installed improperly that wouldnt cause too much heat
-an exhaust blockage is a possibility that could cause me to pump out too much heat, which I would notice by very bad performance in my car.... but I havent noticed that in mine.
-crawford cats put out the same amount of heat as regular cats
-seeing heat under the car after a decent length drive is normal, as well as the plastics getting warm

My main concern about having all that heat under my car was that I was afraid to snap another driveshaft. I figured, whatever snapped it the first time, if it was never fixed, will just snap the new one. If the first one was faultly from the factory than I dont have to worry about that.
Although the call has explained some more things to me, Im still a little nervous about it. I guess its just fear of paying 4000 bucks for a new driveshaft if another one snaps, cause I know Nissan wont cover it, HA.
I was thinking maybe installing some kind of heat shields would make me feel safer or more comfortable??

I still think the comment the guy at Nissan gave me was great though. "Honestly, I would be nervous about parking this car in the grass in the summer". Haha.

 

How about an EGT gauge?

Usually it's rare for a mildly modified car to have a wide variation in exhaust temperature (over stock). Even when this does occur, your first indication will usually be a CEL as your 02 sensors would be the first to break down.

Cheers,

Gary