I've a new downpipe on order for my sti v5 and was wondering if it's worth the effort of lagging it before I fit it?

The car is still fitted with the standard sti tmic so I guess heatsoke could be an issue. Obviously it'll be much easier to do it before it goes on the car but is there any real benefit?

Any pearls of wisdom on this one anyone?

Cheers

 

Playsatan - opinions are mixed about this. Some say yay, some say it's not worth the bother.

I've had a decat Scoobysport downpipe fitted to my 00MY Turbo for a month or so. ALL the heatshields came off during fitting, the new d/pipe hasn't been lagged, and I can't say I've noticed any negative effects (despite several good raggings).

Still early days, I know.

Try doing a search.

Kev

 

I fitted a full Revolution system and had to remove all the heatshields except the one above the Turbo that needed "trimming" to fit. I was a little worried about the heat from the dp causing problems with the power steering and braking fluid which lives close to it. I decided to lag the dp just to be safe.....I suppose it also helps keep the underbonnet temps down and reduce heat soak to the i/c.

 

I would not lag it all the way down but 3/4 's of it Etc, It will help reduce underbonnet temps on standstill Etc & channel more heat out of the backbox (More pops & bangs ) plus for every 5 Degs reduction in underbonnet temps = 1Bhp or something like that

Dean

 

i think it's a must really, it also lives very close to the steering rack. Magnex had to redesign theirs because the twin dump pipe was too close and was drying the grease out in the steering rack, plus it's been said above, the more heat you can cut out of the engine bay the better the car will go

 

Looks like I'll be lagging it then. I've not heard any downsides to it so I guess it couldn't hurt.

Those of you that have done it, where did you get the material from and is there any brands that are better then others?

Thanks again.

 

As it happens I am getting some from http://www.agriemach.com/default.php...sort=1a&page=2

2 of 50' x 2" rolls ... + some straps to hold it down! Dunno about quality etc compared to other sources ...

 

If you only have a top mount I would have thought it a 'must'

There are no downsides, as long as its not already ceramically coated?

I've heard some comments about temps and the speed of gas flow, etc, etc but its all crap

Reduce the underbonnet temps will reduce temps and give more power............

 

i thought if you lagged it the heat built up more and if the downpipe wasnt GOOD quality could cause it to overheat and crack??

or am i talking sh@te ?

 

helps keep the heat away from the turbo

 

no poo

 

how about lagging the turbo too? Any risks/downsides?

Bob

 

Its just more hassle to wrap the Turbo

High end spec apps do this - i.e. high power Skylines

Again its all about keeping the temps in teh engine bay down...... especially near intercooler pipes, air filters, etc

Re cracking - why would you put a crap quality downpipe on? in the 1st place - it should not crack unless its already ceremically coated then it probably would......

 

Exhaust wrap is an insulator and keeps the heat in the exhaust gas for that much longer. This aids flow. Because it`s an insulator it also helps to reduce under bonnet temperatures and protects items in close proximity to the up pipe, headers or what ever else you have wrapped. Headers and turbos are provided with heat shields and if these are removed for any reason then it is advisable to wrap the components with exhaust wrap.
Personally I run with wrapped headers, up pipe, down pipe and turbo and I know it adds some power but I am unable to determine how much.
What is for sure is that for me spool is greatly improved by wrapping.
There is a little experiment you can do for yourself. With the oil at operating temperature but the engine not very hot, 4th gear, 1700 rpm. Now roll the throttle on to flat on the floor and note the revs at which you have 1 bar. Now do a bit of spirited driving to get the whole set up hot throughout and repeat the experiment.
The spool on a hot exhaust system and engine will be 2-400 rpm earlier and this leads me to believe there are benefits from wrapping the exhaust and turbo.

 

Sounds worthwhile to lag the turbo too while I'm at it. Whats best to use for downpipe and turbo....I assume its the weave type wrap and not alu mats?

Also is it worthwhile leaving the plastic shield beneath the engine off? On MY99 it has 'vents' to direct air upwards so I left it on as I was unsure of benefits.

What sort of length is needed fot turbo/downpipe? Somebody mentions 2 rolls of 50ft 2".

Bob

 

2 rolls of 50 foot x 2 inch wide is I think for headers.

Downpipe is ok with 10 metres of 2 inch wide. Depends how tight you wrap / over lay it.

Rally Design supplied mine, and get some stainless jubilee clips too!

 

No difference on spool up between semi warm and hot for me........

 

I've just bought some from a place called Nimbus Motorsport in Yorkshire:
2" * 1/16" * 15' to cover the downpipe along with a stainless "snap strap" kit...cost just under 35 quid including p&p.
Also recommend picking up some "Hi Heat coating" - basically a spray that seals eveything once wrapped up.

Not sure if they have a website but I can PM you their phone number if you want?

Nick

 

scoobyclinic told me not too bother so i didn't.

 

10 meters?????

that seams like a lot of wrap

how many foot is in 1 meter?

 

Harvey - while I also wrap my downpipe, there is a certain logic to saying you only want heat in exhaust gases when it can be turned into power (ie; before turbo). Once it has done this job, you want the heat out ASAP to reduce the volume of the gases and thereby the back pressure presented by your exhaust system.

Of course, I'd rather suffer this penalty than have all that heat in my engine bay, but if you could reduce EGT's significantly directly after turbo (without transferring it to the engine bay) wouldn't this improve power?

Richard