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Power Gain
speedyxjs - 14/2/08 at 08:30 PM

Not locost but this was a reply from the jec forum.

quote:

JaguarXP claim 12-15 HP at the wheels for their nice shiny back boxes. However, if you want a power gain and would be happly with a more 'sporty' tone then you could just replace the rear boxes with a plain tube. I am considering doing this with my '95 XJR, if you use the same diameter pipe you could swap the original trims over for a nice standard look. Smile As the original system was designed for silent crusing there is probably a lot to be gained in terms of power and economy.


How much power could be gained from removing the rear silencers (my car has 5) and what would it do (if anything) to the emissions?

iank - 14/2/08 at 08:38 PM

Wouldn't do anything to the emissions (unless you remove a cat).

How much power depends on a lot of variables, it will need retuning to get any real benefit I suspect.

It will get a LOT noisier though.

RazMan - 14/2/08 at 10:35 PM

I think it is a common dodge with some TVRs - removing the back boxes releases a few more ponies (doubt if it is more than 10bhp though) and makes it sound lovely too.

Dangle_kt - 14/2/08 at 10:41 PM

On bikes back pressure is important, so it aint just a case of bolting on a peice of scaffold pole. I guess it is the same in cars to get maximum BHP.

britishtrident - 15/2/08 at 08:04 AM

The cats are the main source of back pressure ---