Tim4x4

Well-Known Member
Is removing the centre silencer box and replacing it with a straight through pipe (ON A TD5 110)
1/ good for performance?
2/ bad for performance?
3/ no difference on performance just more noise?
I have given my centre box a good bashing and in need of a replacement, I see that a straight through pipe is available and having done a search some say good some say bad.
I have been specific that I am asking about the effect on a TD5 engine because the effect may be different dependent on the engine.
Any TD5 owners who have replaced their centre box with a straight through pipe able to give feedback on the results?
 
The engine breaths slightly better, slightly better performance, makss a lovely noise! However can get a little loud on the motorway but you do get used to it.

I had a mild steel one fitted to my 90 for about 4 years, wouldnt have changed it. Couple with a Decat pipe for maximum benifit.

If youre worried about it being too loud Allisport do a "bullet" mid box, almost straight thru but less 'booming' / more quiet.

There where zero ill effects.
 
The engine breaths slightly better, slightly better performance, makss a lovely noise! However can get a little loud on the motorway but you do get used to it.

I had a mild steel one fitted to my 90 for about 4 years, wouldnt have changed it. Couple with a Decat pipe for maximum benifit.

If youre worried about it being too loud Allisport do a "bullet" mid box, almost straight thru but less 'booming' / more quiet.

There where zero ill effects.

Thank you for the reply, the booming noise you talk about is that caused by long pipe under the vehicle (I will be fitting it to a 110 so 20 inches longer than a 90) or just the extra noise from the back of the vehicle? Could rapping the pipe with exhaust tape stop it? http://www.demon-tweeks.co.uk/perfo...on/design-engineering-exo-series-exhaust-wrap
 
Deleted centre silencer and decatted several years ago. Some booming in the cab, lovely turbo whistle, and engine seems to rev freer. No difference to MPG, though.
 
The 5 cyl engine does have a lovely note even if it is an oil burner. I have a straight pipe to fit on my D2.
Some say better MPG, some dont notice a difference but all seem to agree that it revs easier / quicker, and it sounds better.

I can't wait to get mine on, mine probably won't be as loud in side, as I expect the disco has more sound deadening than a defender
 
Does anyone know where you can get a mild steel straight through pipe?

All the ones I can find are stainless and £40 and upwards, some are silly money. Stainless is wasted on my landy. Surely someone makes a mild steel pipe?
 
I fitted a decat pipe to my 110 TD5 and it did rev up quicker with the decat pipe fitted.
However the droning at motorway speeds (particularly bad at 65-70mph) was wearing, and not a nice noise at all.
Eventually l fitted an aftermarket replacement CAT and the droning was gone.
And l am back to the slower engine response.
What l need is a CAT replacement pipe with a silencer fitted instead, but that does not appear to exist.
 
I fitted a decat pipe to my 110 TD5 and it did rev up quicker with the decat pipe fitted.
However the droning at motorway speeds (particularly bad at 65-70mph) was wearing, and not a nice noise at all.
Eventually l fitted an aftermarket replacement CAT and the droning was gone.
And l am back to the slower engine response.
What l need is a CAT replacement pipe with a silencer fitted instead, but that does not appear to exist.

Was it just the cat you removed or the cat and the centre silencer which induced the droning.
 
Just the CAT.
Does make me wonder if my centre exhaust box is knackered? As l was told that fitting a decat pipe would hardly make any difference to the exhaust noise levels....after all the CAT was only fitted to the Defender TD5 from 2002.
 
Just the CAT.
Does make me wonder if my centre exhaust box is knackered? As l was told that fitting a decat pipe would hardly make any difference to the exhaust noise levels....after all the CAT was only fitted to the Defender TD5 from 2002.

Yes early TD5 defenders had no cat fitted as they met the emission regs. I have no cat fitted and I don't suffer with droning from the exhaust.
I am looking to replace the centre section with a straight through pipe as my center silencer has taken a good bashing at the weekend and has started to leak.
It is a big old chunk of metal having a large flat surface facing forward just waiting to be hit by rocks. I am hoping that a plain pipe will help to reduce this risk without making too much noise both inside the cab and outside. Improved turbo response will be a bonus Ho and the cost of the straight through pipe is also making it more tempting.
 
Just the CAT.
Does make me wonder if my centre exhaust box is knackered? As l was told that fitting a decat pipe would hardly make any difference to the exhaust noise levels....after all the CAT was only fitted to the Defender TD5 from 2002.

Still no clue what this droning noise is your on about. Just decatted my 110 and theres no drone, same on the 90. Just louder exhaust caused by the straight thru. Tho the 110 has a bullet silencer fitted now which is much better than a standard straight thru imo

Im thinking your center box is nakered
 
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Still no clue what this droning noise is your on about. Just decatted my 110 and theres no drone, same on the 90. Just louder exhaust caused by the straight thru. Tho the 110 has a bullet silencer fitted now which is much better than a standard straight thru imo

Im thinking your center box is nakered
Do you have the bullet silencer replacing the centre box and the tail end silencer still fitted or just the bullet silencer at the tail end?
 
Decat - Bullet midbox - standard rear box.

Still throaty when you want it to be but quieter when cruising
 
Does it give any more power? I pull a big ifor williams trailer with my 110 td5 and find i need to give her welly all the time with the trailer and can almost watch the fuel guage drop, i was looking at decat and straight through at the back box to give her a bit more pull so i dont need to have throttle pressed flat all the time. Next stop after this job is a bigger cooler then the stage 2 or 3 remap. The growly sound doesnt bother me, im after more grunt, but if it does sound good then thats a bonus!!!!!
 
Does it give any more power? I pull a big ifor williams trailer with my 110 td5 and find i need to give her welly all the time with the trailer and can almost watch the fuel guage drop, i was looking at decat and straight through at the back box to give her a bit more pull so i dont need to have throttle pressed flat all the time. Next stop after this job is a bigger cooler then the stage 2 or 3 remap. The growly sound doesnt bother me, im after more grunt, but if it does sound good then thats a bonus!!!!!
I can’t give you power figures, but it seems more free-revving to me.

I’d say try the decat, centre silencer delete and EGR blank, then a stage 1 remap (inc. bigger cooler) and see where it gets you.
 
My 110 TD5 goes very well with a basic remap, and it’s been turned down due to too much smoke.
That must be some trailer you are hauling to hold a TD5 back with a stage two remap in it.
Is it full of cows?
 
i dont have a remap yet, just standard, already blanked the egr, not a huge improvement but certainly feels better. I took a discovery to the local specialist the other week on the trailer and she worked her a*** off setting off, which is understandable, but general pulling just seems underpowered, almost stopping to drop into first on hills. Going to order the pipes, will do a full tank mileage and do one after fitted the pipes and post them here, hopefully help people out on economy. What do you mean it has been turned down because of too much smoke?
 
Mapping means adjusting the air to fuel ratio. Too much fuel or not enough air leads to black smoke (unburnt fuel)

Other types of mapping involve telling the ECU to inject more fuel, same as above.

Look up the TD5 air box mod, it should let your turbo spool a touch faster, you can also turn the boost up a couple turns on the wastegate actuator for a little more power.
 

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