Hi all I've just brought a decat downpipe and centre for my wagon..I was thinking about wrapping the downpipe because i can but just wanna check if there's anyone looking atthis who's done this and did they feel any benefits.
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thanks

 

It IS worth doing. Best to do the headers and uppipe too, though.

With all three done, the hotter gasses move faster and aid turbo spool up. Up to around 150-300rpm sooner!

 

Just a thought, (sorry to hijack the thread) but does wrapping the headers/up pipe/down pipe make the exhaust louder?

 

Not directly, but it does significantly reduce noise radiated into the engine bay, which in turn makes the exhaust noise seem louder and more "focussed".

 

Thanks for the heads up joz and no probs jamz you leap in there...this presses for another question how much is one going to need...found a nice web site that give a choice of different wraps..last thing i need is choices of wrapping cos it asks more questions which one is best or maybe who cares there all going to do the job...

Dust Buster, Air Precleaners, Spark Arrestors, Engine protection and ancillary products, for the earthmoving, agricultural, truck, bus and the automotive markets.

 

I think one roll of 50ft is enough to do all three(?). I think decent stuff (e.g. DEI) is around £70 IIRC(?)

 

Seems or does make it louder? I have a track car you see and tracks are strict on noise... I have not got any of my exhaust wrapped, although i want to do my headers to reduce heat getting in the oil filter, but if it makes it louder, i may only do a little section.

 

Couldn't answer that question affirmatively without doing a before 'n' after with a sound pressure level meter.

I would suspect the answer is "seems", purely because wrapped exhaust manifold and downpipe are so much quieter than standard ones. You only realise how much the press steel shields "ring" when you get rid of them.

 

A 3" open neck downpipe will take three quarters of a roll 2" x 50 foot. A set of tubular headers with the runners wrapped individually will take the best part of a 50 foot roll when you include the uppipe.
With whatever is left over you could wrap the hot side of your turbo which also helps.
The advantages of wrapping are a reduction in under bonnet temperatures and the gas is kept hot promoting easy gas flow, earlier spool and quicker turbo warm up when applying power.
Having tried all the wraps I stick with DEI exhaust wrap which I sell at £55 a roll.
If you look at the Titanium wrap in your photograph you will see that the weave is relatively open and I don't see how an open weave can restrict heat loss as well as a closed weave.
I did try wrapping a whole exhaust system to reduce in cabin noise but it had no effect and I did not notice any difference to the outside noise.

 

this is the wrap i used, fairly cheap from this place compared to others,

http://www.lister.co.uk/Uploads/prod.../Thermotec.pdf

 

Valuable information thanks for the post...you say you sell it..yuo have a location for that please..many thanks

 

I have used all the heat wraps I have come across over many years but so far I am settled on DEI wrap because the thermal properties are as good as anything else I have found and better than most. It is close weave so there are no holes when streached. It has a stitch down each side to act as a guide to overlap so it is easy to use and because there is less excessive wrapping, economical.

Here are the instructions I have made up for this wrap which I sell at £55 per 50' X 2" roll.

Heat wrapping is not difficult if you follow these instructions but you cannot expect to achieve a professional standard on your first heat wrap operation unless you follow these instructions exactly.
Because of the cost of heat wrap ties I only use stainless steel tie wire and generally the more ties the better the job.
To use tie wire it is best to have a set of tie wire pliers/ lock wire pliers which makes twisting the tie wire that much easier.

The DEI heat wrap has a stitching down each side to show the amount of overlap required and you should follow the overlap guide stitching where possible. This is not possible on the inside of tight bends.
The wrap should be applied damp but not wet. There are chemicals in the wrap to help it bind and these should not be diluted out. You can use a house plant leaf sprayer or any other water aerosol/spray to dampen the wrap or set the tap to a very fine trickle and run the wrap through the trickle quite quickly. In a few minutes the water will have spread evenly throughout the fabric to dampen it. Do not let the impregnated chemicals run out.
Wrap from the bottom to the top with the appropriate overlay.
Keep the wrap as tight as possible.
Remember that the wrap on the outside of a bend requires more material and therefore the corresponding inside of the bend will have big overlaps and on a tight bend this can be almost 100%.
Do not cut the wrap in to short lengths but try to apply in continuous lengths and certainly 15 feet at a time.
The rolls come in 50 foot by 2" .
A 3" open neck downpipe wll generally take three quarters of a roll of wrap done properly.
Remember. Keep it tight.
Tie at the end and then every 3 or 4 inches but on curves or corners you can increase the number of ties.
The tie must be applied while the wrap is still damp.
Cut off any strands and loose ends.
When put on the car first there will be a lot of moisture released from the wrap. Do not be alarmed.
On damp and humid days the wrap will absorb moisture so again there will be a lot of steam.
It is quite normal for the wrap to smell for three weeks after applying as it dries through thoroughly.
Happy wrapping.
If you need further assistance please do not hesitate to contact me.
Regards,
Harvey Smith.

We have just removed a set of headers and uppipe from a car that we wrapped over three years ago. The wrap is in very good condition. Two small areas need touched up where there has been some physical damage from road debris, a lump of wood or a bolder perhaps. So wrapped properly it can last for years.