Jump to content
Smokydiesel

Straight Pipe Instead Of Middle Silencer

Recommended Posts

Spent the best part of the evening, replacing the middle exhaust silencer with one of those straight through-pipes I bought at the Scorpion stand in Malvern last weekend.

Must say I’m a bit disappointed by the result: <_<

More BHP ?...well could be that it pulls just a bit better low in rev’s

Great sound ?..what great sound ???? when I try real hard I can hear a distant dark-ish rumble, but that’s it. No burbling V8-sound, no exiting turbo whistle.

(makes you wonder why Land Rover fitted that huge silencer in the first place..)

Anyone fitted one of these…was I expecting too much ?

Cheers,

Edwin.

Share this post


Link to post
Share on other sites
makes you wonder why Land Rover fitted that huge silencer in de the first place..

I reckon they were just being lazy - the exhaust setup didn't change from the n/a diesel and petrol to the turbodiesels which hardly need silencing because the turbo takes most of the energy out of the exhaust.

When (?) my exhaust goes I will replace the middle silencer with a straight pipe, though not one from ScrapIron. Any of our local exhaust guys will make one for cheap.

I say when because it has now lasted 10 years and shows no sign of corrosion. It's the climate that does it, of course.

Share this post


Link to post
Share on other sites

I did it some years ago,not a SR nor Eq*uip*4x4 but made by a mechanic here,

cos I had chopped the o.e. one and it was a bit rotten and had holes...

No rpm/torque improvement (as far as I feel) but a louder sound and turbo whistle...

:)

I'm used now,but I had the chance to try another Tdi of a friend some time ago (stock exaust) and I got shocked...

:blink:

Damn,so my truck too was so quiet before..?!?

:lol:

P.S.

I'm tempted to fit the straight pipe which goes where the cat is now,

but it's the only barrier which could keep some water out now...

Share this post


Link to post
Share on other sites
had the chance to try another Tdi and I got shocked...

Mmmmmm...mine's a TD5, yours a Tdi, could be a difference there...perhaps.

Edwin

Share this post


Link to post
Share on other sites

In theory, you will not get more power out of a wastegated tdi or TD5, but the lower back pressure should allow the turbo to spin up faster and reduce 'turbo lag'. Did either of you notice a difference?

Share this post


Link to post
Share on other sites

I removed mine from the 110, 2.5 petrol for a short while.......i feel i had a tad more power but the noise and strange harmonic vibrations had me putting it back in :)

We have a glass packed, straight thru silencer over here called a Cherry Bomb, they have a wicked sound on NA automobiles no matter what the engine........... :)

Share this post


Link to post
Share on other sites

I know of a 200tdi running with a Janspeed exhaust, not a single silencer along its whole length, and it sounds like a tank, much nicer than any silly V8! :P

Share this post


Link to post
Share on other sites
the lower back pressure should allow the turbo to spin up faster and reduce 'turbo lag'.

I'm not sure about the turbo lag, I'm under the impression that it pulls a bit better low in rev's....but that could also be me imagining things ! (and hoping that I didn't burn 44 pounds for nothing....)

I only drove the car for a few miles this morning, will take it on a longer trip tonight, let's see how it feels ! :unsure:

Share this post


Link to post
Share on other sites

You can hear the turbo whistling on almost every Eq*uiPPPPed Rover around here.

A friend of mine had the exaust cutted a bit in his Disco and you hear it easily.

Mind if you're "in" the cab and not outside it could be less easy.

Ask a mate to stomp on the pedal while you're out...

:)

Me I thrown more than 44 pounds away IIRC...but,oh,it was ruined anyway...

Share this post


Link to post
Share on other sites

Hi all

On my 300 Tdi I have only got a single box and a short exhaust system. The silencer is next to my transfer box and the whole thing finishes short of the rear axle with a nice bend so it points at the road. The silencer I am using is a competition straight through one I brought from Burtons performance many years ago that had been lying round for ages waiting for a use to appear & it did. I have not done any instrumented test or anything but I would say that the turbo spins up faster & is moving more air because I no longer get a lot of black smoke in the midrange. This could also be attributed to the fact I also have a decent sized airbox fitted where my heater used to be that has a pressure drop 6 times lower than the std item bolted to the cylinder head bracket & fitted with a K & N filter !

With a turbocharged diesel you do not need heavy levels of exhaust silencing as noise is not a big issue. Short systems using at least 70 mm bore pipe will allow the turbo to spin up more freely simply because you are increasing the pressure differential across the exhaust turbine.

I will say that I do produce a strange noise when going through a tunnel, this I believe is a reverberation of the exhaust gas hitting

the floor and bouncing around the tunnel as the outlet is pointing down and is close to the road in comparison to a normal rear outlet.

Share this post


Link to post
Share on other sites

Very nice, Spectric. Your e-mail address is "co.uk" so you will be OK with the K&N filter. But if you ever consider going to a country with a dusty climate, you must change it for a paper filter or pay the consequences, as I did.

It hasn't rained here since April, and it is very dusty, even in town. In the UK the rain takes all the dust out of the air, a sort of pre-cleaner :)

Share this post


Link to post
Share on other sites

I’ve got a straight pipe in place of my mid box on my TD5, it is louder, and you can hear a strange whistle when the thing is on tick over (from outside only), but as for more power/less lag, cant say I’ve noticed. It is strangely reminiscent of a chieftain tank when pulling away. One thing that did come to light was that it was over-boosting after fitted with a Jeremy Fearn intercooler and chip, which he did say was not something that happens with a stock exhaust system, so must be doing something.

Share this post


Link to post
Share on other sites

Forgot to add, the ramp-over clearance is better, which, after all is the main reason for fitting it. And the old bus has just passed her MOT with it with flying colours.

Share this post


Link to post
Share on other sites
............ It is strangely reminiscent of a chieftain tank when pulling away..................

As in choking clouds of blue smoke ? :):):)

Share this post


Link to post
Share on other sites

i've got one on order from Allisport so will comment when it arrives on mpg, sound etc.

main reason is that the gkn overdrive only has mm clearence from the mid silencer which i had to drop 2" on fitting the GKN anyway, so it also hangs down alot and catches going over mole hills!!!

a friend recently fitted on to his td5 90 and remarked what a difference his amd on low down pick up (its already chipped) hence the other reason for going for it!!!!!!

will keep you posted.

yes big moles around these parts!!!

as for turbo whisltle, its noce to hear the turbo is still going having just trashed my last one!

Share this post


Link to post
Share on other sites
Guest diesel_jim

on my 300Tdi 90 i had a hand made 3" stainless "straight through" system, the engine revved very well,but i used to get a headache after several hours of driving it, so i sold the system and fitted a "standard" (ish) system back in its place...

standard downpipe from the turbo,connected to a Rimmer Brothers V8 sports silencer left over from my 3.9 90, and utilising the rimmers tail pipe (which is more or less the same as a stock item but in stainless), so the engine now breathes as it did with the 3" straight through pipe, there is a little turbo whistle, but not much, and i don't get a headache or sound like a chavved up boy racer! B)

Share this post


Link to post
Share on other sites

I have to say that I thought straight through pipe definitely widened power band noticably on my TD5.Also increased noiselevels inside.Am interested that it should pass emissions test without cat silencer.

Share this post


Link to post
Share on other sites

My experience is the same as that of 'eyore'. Taking out the middle box has given my Td5 a definate boost in torque.

Passed the NCT without a problem.

Modified 2001 Td5 with 90,000 miles on the clock.

Share this post


Link to post
Share on other sites

I understand that a 110 and 130 exhaust is just a short piece of exhaust pipe that is coincidentally the same length as the first silencer on a 90 or 110. £37 for this bit of pipe, and I always thought that there was a noise and small performance improvement.

Les.

Share this post


Link to post
Share on other sites

I bought a s/s side exit exhaust kit from Gwyn Lewis. Now I get a lovely turbo whistle, but the increase in noise is taking some getting used to. I have just got to finish it by triming the exit hole in the panel. The exhaust is just catching on start up and at low rev's

Dave

Share this post


Link to post
Share on other sites

Dave do you have any contact details for the guy you got your side exit from? i am thinking of going this route with a 200tdi to stop the exhuast getting repeatedly squashed on events. what did you apy for it?

fitted the Allisport straight through pipe today. as normal a simple exchange job took ages 2.5hrs!!! the old , well not that old 6 yrs, exhaust was corroded together and two of the three rear nuts had to be ground off. then i didnt have any 17mm nuts to put it back together (screwfix lost the order.) so decided to go 19mm instead, bolts fitted the Allisport flanges although the existing exhaust needed the clamping holes enlarging slightly. so one knackered (burnt out i think) 850W Bosch drill later and bruised knuckles and sore arms from filing the holes out its all together. except i couldnt find the exhuast compund to reseal the rear connection so used the old LR supplied gasket - and its blowing!!! typical. front one is tight as a dream.

start her up and yep def louder ( not something i was particularly after) short 10miles test run and it certainly picks up quicker, that is the turbo is spinning up quicker, to be expected as less resistance to the exhasut gases so they flow faster spinning the exhaust impellar enroute.

so pickup def alot better at low grount and much louder when under load around max torque 2100rpm it seems loudest. i will have to see if mog changes and what the noise is like at cruising speeds. hopefully mpg will improve a little, when not pushed, and as long as its not too loud at 60/70mph then it will stay on.

so far impressed with it, however still alot of money for a bit of pipe.

Share this post


Link to post
Share on other sites

Mike D fitted one from Twisted performance £55 at Billing IIRC

it sounds like a V8 on tickover.

on the way to Slindon this year he was pushing my 300TDI up the hills nearly

no big suprise I hear you thinking....

he was towing another V8 90TC on a trailer at the same time...

we had a small trailer with 5 wheels onboard....

Share this post


Link to post
Share on other sites

my conversation with Mike went along way to convincing me it was the way forward.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×

Important Information

We use cookies to ensure you get the best experience. By using our website you agree to our Cookie Policy