Need Quick Help-Side Sill Insulation Removal or Not

[Tomer]

My side sills on my 96 RT/10 are no more than a day away from being painted (business day that is) and I would like to know if anyone has successfully drilled out the rivets, removed the insulation, then sprayed the inside of the sill with the VHT-1500 paint, then managed to re rivet the insulation back onto the inside of the sill...

I installed HF cats and Corsa cat back system, but my sills were starting to yellow a bit, and the paint is bubbling around most of the rivets...

My confustion is that in previous posts someone said the insulation is only near the cat (not correct, my insulation runs the entire length of the sill) and that its easily removable from the inside with some sort of clip (again, not correct).

I am wondering if one drills out the rivets, will the holes in the insulation get enlarged and then you really can't get a good hold again? Also, the factory rivets have a little washer on the inside holding the insulation to the sill...Is this anything special or can one install a washer on any generic rivet and that will provide all the hold you need...

Sorry for the hurry up, my snake is almost ready!!!

Tomer
96 RT/10
Northern California

 

[varanus]

Hi Tom, I know this doesn't answer your question, but the hi flow cats are so much cooler than stock that i wonder if the sills will turn yellow still without all the heat you used to have.

Kevin

 

[Tomer]

Kevin, thats a good point...I should have added that to my post...

The question is, with the high flow cats, should I even bother with the VHT-1500 paing and removing the insulation?

Tomer

 

[Ulysses]

Let me get this straight, you have HF cats and it was still yellowing? Or was the yellowing already occurring?

I can see the urgency. If you carefully drill out the rivets, you shouldn't have a problem. The washers you are talking about sound like a rivet washer. They are bought separately from the rivet, but made for rivets.

Seems to me, with the HF cats, you shouldn't have to worry about spraying VHT in there. Can you put your hand on the sill and keep it there after a long drive?

Ahhh! Saw your post above. Yeah, after installing HF cats, you shouldn't worry about VHT1500.

 

[Tomer]

Ulyssess, thanks! I guess you don't have the HF cats?

Yah, you got it, but my sills were yellowing a little with the
stock cats...

SOunds like with the HF cats I will forget the VHT-1500 paint.

If anyone else can confirm that they have put in the HF cats without the VHT-1500 paint, and seem to be having a good resuls, please advise!

Tomer

 

[Jack B]

I measured temp with stock cats and with the Roe high flow cats. I used the elliptical cat which is in very close proximity to the sill. The highest temp I could get with the high flow cats was 90-100, versus approx 130 with stock cats. These were taken with an ambient of 70-80. There is no heat problem with the right cats.

These readings were on a Gen 1. Please noted the elliptical cat is also impossible to mount to the front of the muffler on the Gen 1. I reversed the positions, because, the sill widens to the rear and thus has more room to mount the larger cat. I just bought a Gen 2, this exhaust system is for sale.

 

[shifter]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>
I measured temp with stock cats and with the Roe high flow cats. I used the elliptical cat which is in very close proximity to the sill. The highest temp I could get with the high flow cats was 90-100, versus approx 130 with stock cats. These were taken with an ambient of 70-80. There is no heat problem with the right cats.
<HR></BLOCKQUOTE>

I have a Thermal gun, and even with Roe's hi flow elliptical cats myself, I get temperatures in the 130 - 140 range. Stock I used to get 160. I even have the collector to Cat inlet wrapped with Thermal Exhaust wrap.

Maybe the difference is the Gen I vs Gen II, but I have a hard time visualizing 95 degrees on the sill in an ambient of about 75 degrees.

 

[Jack B]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by shifter:
I have a Thermal gun, and even with Roe's hi flow elliptical cats myself, I get temperatures in the 130 - 140 range. Stock I used to get 160. I even have the collector to Cat inlet wrapped with Thermal Exhaust wrap.

Maybe the difference is the Gen I vs Gen II, but I have a hard time visualizing 95 degrees on the sill in an ambient of about 75 degrees.

<HR></BLOCKQUOTE>
The temp readings were with the Balenger headers installed. Per haps the better flow was part of the temp reduction. I have checked it several times. Remember, the reading is a temperature rise, if you start in a high ambient such as 90-100, your reading is probably right. Immediately after cruising speed the temp would always be cool enough to hold your hand on any part of the sill. I also used an infrared (3M) gun.

I just purchased a Gen 2, I have not measured it yet, however, the sills seem to run hotter than the Gen 1. It seems as though it should be the opposite, there is a lot of restriction in the sill of a Gen 1. I will be putting the Balengers on the Gen 2 and removing the cats. I will do a before and after at the same ambient and post it later in the month.

 

[shifter]

After some thought, the key to cool temps in the sills is getting some airflow. I wonder if a couple holes, say 1.5" diameter in the fiberglass front wheel well, directly in front of the sill would allow for some airflow? It seems there is an exit through the back of the sill where the cat back pipe comes out, to allow the sir to escape. I suppose the downside would be some aerodynamic lift. Though you could always plug the holes with grommets or cover with tape if it made that much of a difference on the track - however I'm not convinced that it would.

Conversely, that might just be a low pressure zone, so hot air from in the sills might be drawn out? Could probably test with a small hole and some machine oil, or some string.

Maybe a spring experiment?

Jack B,
My sills must be hotter then yours because after a hard run, I have a difficult time keeping my hand on them in places. I can, but it's quite hot.

 

[Ulysses]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>After some thought, the key to cool temps in the sills is getting some airflow. I wonder if a couple holes, say 1.5" diameter in the fiberglass front wheel well, directly in front of the sill would allow for some airflow? It seems
there is an exit through the back of the sill where the cat back pipe comes out, to allow the sir to escape. I suppose the downside would be some aerodynamic lift. Though you could always plug the holes with grommets or cover
with tape if it made that much of a difference on the track - however I'm not convinced that it would.<HR></BLOCKQUOTE>

JonB at Parts Rack sells louvres that mount in the front of the sill and will improve air flow. The real down side would be if flammable debris got in there somehow.

 

[Tomer]

Ok, so if there aren't any last minute additions, I am going to just have the shop re-paint my side sills, and I won't bother removing the insulation and spraying the inside of the sills with the VHT-1500...

Thanks for all the advice, wish me luck....

In general, I think the paint is going to bubble around the rivets eventually (I imagine the rivets themselves conduct the heat since one end is inside the insulation, with direct exposure to the cat heat)...However, without inspecting the underside of the car, me thinks there are only the 2 rivets visible when the hood us up...

Tomer
96 RT/10 white with blue stripes