exhaust wraps.

Hey guys.I wanted to find out if it is neccessary to fit exhaust wraps to a stainless steel exhaust system?

 

[old-git]

Hey guys.I wanted to find out if it is necessary to fit exhaust wraps to a stainless steel exhaust system?

It is not necessary on any exhaust system, unless you have heat that you wish to keep in the pipes

The type of metal used for the exhaust is irrelevant, they all get bloody hot!

 

[weber44idf]

its common practice to wrap exhaust extractors / headers etc as an alternative to ceramic coating / flow coating the internal passages . the theory is that the exhaust gasses flow easier when hot / thinner , cold exhaust being thicker and in turn gives more backpressure / resistance to flow and drop in performance .
the gain is very small , but in class raceing EVERY LITTLE BIT COUNTS

 

[thexav]

It keeps underbonnet temperatures down so if you have an open induction kit fitted you might actually see a power increase unless you have a cold air feed pipe.

 

[Dumfriesman2]

It keeps the heat in the exhaust...better exhaust flow...cooler engine compartment...ECU senses cooler temp and gives the engine more fuel with the cooler air.

 

[lutonmatt]

why doo you want to do it
think you can get the wrap off ebay

i have read ina few places it does not really do much for the price you pay for the wrap it does not do much

but i have never done it on one of my cars and dont think i will

 

[Dumfriesman2]

I have only seen it on competition cars...and it is usually on the cars that
are doing best...but for a road car,don't bother...

 

[ez64]

I am thinking on doing this for my V12 as the cooling is always an issue in every climate, exhaust wraps though tend to keep the gaskets hotter and there was a study showing increased wear on exhaust gaskets at the head and the first U clamp.

 

[coupe]

done it on my xjs.

blooming fiddly job.

got some left over.

 

[ez64]

I'll do it when the heads come off so it will be a bit easier as the exhaust manifolds will have to come off anyway, makes me tired just thinking about that job

 

[Dumfriesman2]

Good lord,yes! I would never attempt it while the manifold was still on the car! I have just taken delivery of my exhaust wrap,along with fast road cams,alloy throttle body,vernier pulleys and new laminated head gasket for my Rover 25 that I am tweeking for the Scottish Sprint CHampionship next year.
Does anybody else wonder what purpose the flimsy bit of aliminium serves in front of the exhaust manifold...mine is going on the tip.
What about a good exhaust setup that doesn't cost the earth?
The local Rover guru has told me to change the manifold for a 214 manifold to get rid of the pre-cat on the R25.

 

[ez64]

I am pretty sure that will be your exhaust heatshield, if rover thought it was needed I would replace it rather than chuck it.

 

[Dumfriesman2]

But I am now wrapping my exhaust.....and it is all rusty and looks disgusting...and Rover thought the car needed a pre-cat too.

 

[MasterAuron]

I am pretty sure that will be your exhaust heatshield, if rover thought it was needed I would replace it rather than chuck it.

Since when did Rover know anything about making cars? Surprising they lasted as long as they did.

Unless there's any wiring or anything in the direct path of the heat, bin it imo! They don't actually do much shielding of heat anyways.

 

[Dumfriesman2]

Exactly....their head gaskets weren't very good...

 

[dpsubaru]

Where is the manifold located at the front end, (just behind the radiator (then the heatshield may protect the radiator from overheating?) or the back of the engine?

 

[Country Bumpkin]

Here's a couple of phots of my front and rear manifolds with/without heat shields and with wrapping.
We made the heat shields from stainless purely for looks, aluminium would dissipate heat quicker but these do look good.
I have kept the images small just for the site space usage.
If you want to see them in full size, there's a few phots HERE

 

[Dumfriesman2]

yes,I see you wapped the exhaust so didnt put a heat shield there...

 

[Country Bumpkin]

Yes, there's a heatshield, look at the third phot. The first phot was whilst we were making the front i.c. pipe.

 

[Dumfriesman2]

Since we are talking about exhausts....does anybody know if the R214 exhaust manifold can be a straight replacement for the R25 mainfold?
I want to get rid of the R25 pre-cat that is built in to the exhaust by putting in a 200 manifold.

 

[dimes1827]

aside from keeping the pipes hot with the exhaust wraps, what about taking out a heat shield and just exposing the exhaust pipes?
is there a significant effect in engine performance if the heat shield is removed from the stock engine?

 

[Dumfriesman2]

The general consensus in the paddock is that exhaust wraps:
A.) Keep the heat in the exhaust and encourage better flow of the
exhaust gases
B.) Keep the engine bay cooler,thus allowing cooler air into the induction
system and giving more power.
C.) Keeps the heat from the exhaust manifold away from the radiator thus
helping to make the engine run cooler.

The heat shield in the Rover 25 is actually placed in front of the exhaust manifold,a few inches away,between the manifold and the radiator,and in my opinion only keeps the heat IN the engine bay and away from the radiator.