heat blankets on cats?

How do you like them on the headers? My indy says they’ve had people take them back off because of the smell.

 

well the factory cats already have a layer of heat insulation around them

 

Ive had blankets on my cats for a few months now. Im glad i put them on. Temp of cats are about 500 to 600. With blankets on its greatly reduced. Less heat radiating in the engine bay

 

Actually the temp of the cats has increased with the blankets, which, depending on the increase, could lead to cat failure.

 

Capristo offer theirs with or without blankets

 

The actual temp of the exhaust going through the cat is the same with or without blankets, only difference is less radiated heat with the blankets on. Cant see they are going to increase the chance of a failure.

 

With your aftermarket headers and stock cats, are you getting CELs?

 

Be careful, you will drive some heat back into the heads,

you will also get more performance however

 

I agree. I would not install blanks for this reason and for the reason that they look horrible.

 

The OP quoted putting blankets on OEM cats, which I believe are 400 cell. Capristo cats are 200 cell, thus less restrictive and less prone to heat build-up and failure.

 

Its still the same exhaust going through them at the same temp or am i missing a point here

 

To say the blankets look horrible is ridiculous.... you can't even see the cats on a 360 or 430

 

It is quite easy to change the fwd lambda sensor on a 360, which means the cat is visible.

If the cat (or header) is no longer allowed to radiate heat then the cat (or header) material and the downstream exhaust will both have increased temp.

 

The increased Heat is debatable. And you may be able to see the cats a little bit on the 360 but on a 430 there is a heat shield over top of them. To say a heat blanket would look horrible is ridiculous. I guess heat blankets look horrible on headers too. Like as if everybody's going to look down at your cats and say how horrible your cats look.

 

They do That's my opinion of course

 

I have Capristo cats with blankets, but I have wrapped over them. I wasn't happy with the engine bay temperature after a hard run.

New exhaust fabrication
The previous exhaust I'd made was nearly whisper quiet with the standard manifolds and cats, but as I came to find out, too loud at low RPM with the Capristo manifolds and cats. This was a silenced X-pipe so I cannot imagine how awful an un-silenced version must be for regular use.

- I had to find a solution - cue more cutting, measuring, and welding!

- I wanted to retain the X-Pipe because it sounds good, but add a silencer like the IPE and Kline system. I'm viewing this as a test because if I like how it turns out I will buy the Inconel Kline system. I started with two large radius U bends in 2.5" stainless. The radius was too large so I cut them in half and welded them back together.

- I then cut off the ends of the modified U bends and welded the two together.

- I've cut up my original F430 tailpipes to make use of the valves and the various bends.

- Photo to show the finished valved X-Pipe section. I also cut up my previous exhaust to use the bends to the cats.

- I need to upload some more photos, but I used the standard F430 silencer but modified to remove the heavy heat shielding and mounting flange. I have replaced the mounting flange with quick release V Clamps.

Heat management
After a few good runs through the Alps and in 40 degree ambient temps through Italy I had noticed that the car suffered from heat soak if driven at slower speeds for a short period after a blast - this is when the engine bay does not have the benefit of the various air feeds. The main cause will be the air box, which despite having two cold air feeds, is mounted directly in front of the exhaust silencer, and on top of the cats. Not ideal.

- I've insulated the air box with Thermo Tec Heat Barrier. It's not cheap for what it is but makes a decent difference.

- The top of the engine lid used to get very hot above the exhaust, so I've added Heat Barrier directly above the silencer.

- The visible parts of the cats glow cherry red after a good blast, and despite having Capristo blankets fitted - which do a good job - there was room for improvement. I have applied heat wrap over the Capristo blankets which has worked a treat: I can now hold the cats after a good drive.

- Cats and finished rear exhaust lower section wrapped.

- New rear exhaust lower section installed. I'm really pleased with how this turned out: I designed it to be removable in-situ without the need to remove under trays or move the cats.

New exhaust mounting system
I have taken the opportunity to simplify and lighten v1 of my mounting system. The premise is to make the rear most mount more sturdy and do away with the cat mounts on each side. This is the same approach used on the Scuderia.

- I've used three Powerflex poly isolators and some custom made hangars that were originally designed for the rear of a Metro!

- Mounting assembly completed and the first of three mounting rods.

- The assembly incorporates mounts for a Nimbus heat shield that I made to protect the isolators.

- View from the rear - the arms on each side are movement limiters to prevent lateral movement in the exhaust during hard cornering.

- Here are the three mounting bars I fabricated - one for the X-Pipe section and two for the silencer - one on each side. The total weight is less than that of the old version.

- Now I've done away with the cat mounts - a la Scuderia - I could swap all of the rear gearbox mounting studs for the plain bolts from a Scuderia. I could also replace the heavy U clamps with Mikalor clamps, saving more weight.

Weight savings to follow in a future update, and more adventures with the car.

 

Great job Mark! Looks really professional!

 

That looks great

 

Thank you! Engine bay temperatures are noticeably lower when I open the lid. I will take some readings.