Exhaust Mod-Which One?

[latebreaker]

Hi All,

I'm very tempted to make my V8 more vocal...especially after hearing the lads exhausts at Weston for the STR 10th Anniversary.

It seems its a choice between the Milltek Full Cat Back System and Adamesh Rear exhausts.

Has anyone fitted either of these and can provide some feedback. Ideally I'd like to hear some more noise when accelerating and at startup(but ot essential), but would like to maintain the serenity at cruising speed.

[jBlackwell]

Hi Late,
Dont forget the Club offers a fantastic system for the S-Type. My brother has one on his 3.0 V6, and Graham Searle has one on his 4.2 V8, the noise is simply wonderful. Not over bearing, but it makes people notice.
Having recently had the pleasure of using Graham's V8 I can confirm you get noticed and you can see their quizical look of "thats an S-Type Jag, but it sounds good". Oh and if you are a little more enthusiastic with the throttle, you are well rewarded.

£160 is bargain price too considering how much they were for sale.

http://www.jec.org.uk/shop/112648/speci ... ystem.html

James

[latebreaker]

Hi James,

Thanks for your feedback.

I hadnt thought of looking on the clubs tool & spares offers. £160 is a bargain when compared to the Adamesh or Milltek system.

I assume the clubs exhaust would also fit an STR?

Would you happen to have or know where I could find if available any sound/video clips of either your brothers V6 or Graham's V8 exhaust in action?
I'm trying to work out what benefit you would get from potentially spending more on the Adamesh or Milltek options.

If the clubs exhaust offer a similar performance then I know where my money would be spent on

Thanks

Krish

[J44EAG]

I have a 60mm Miltek cats back resonatorless system on my V8 4 litre.

I had to sleeve UP just aft of the cats because the V6/V8 exhaust is 50mm pipe. I suspect that the Club exhaust is 50mm so you might need to sleeve DOWN to fit an STR. That would be restrictive.

My Miltek cost around £1000 fitted some 4 years ago. It is exceptionally robust in construction and is as good today as it was when first fitted. Rather loud when first fitted, with use it has oiled and coked up and is a little quieter now. It changes to character of the car from a quiet refined cruiser, so something vastly more intrusive. It can get a little tedious on long journeys, so that is worth consideration. Sometimes I do find myself wanting to shout at it and say, "Arr, shut up for crying out loud"!

Make no doubt about it. The Miltek does turn heads in the street. Pedestrians definitely get the best soundtrack. Different sounds outside the car compared to within.

Mike

[latebreaker]

Hi Mike,

Thanks for your feedback. Is there anyway of finding out the size of the club's exhaust?

I've been trying to sell it to my dad and he reckons the standard exhaust sounds good. I tried to highlight that it might sound good from the outside, but from the inside it's too quiet...lol
I do hope at cruising speed that their isn't a significant amount of sound intrusion.

BTW,
What products do you recommend the clean exhaust tail pipes?

Krish

[Martec]

After reading this post the other day I phoned my local spares place and asked the price of a set of bosal/timax rear boxes for a 3ltr V6, £140 for one side, the other is not available at present, these guys are usually very good.

As the offer is only on until Jan/feb next year and sod's law one of ours is bound to split after that date, the boss told me to order a set. Today they arrived, SS and shiney so tomorrow I'll check them for size and fit, then store them until needed.

They are small cherry bomb type silencers compared to the big almost square lumps that are in there now (assumed to be Jaguar standard fit).

Brian

PS I must keep an eye on Annies bargains!

[J44EAG]

There are two common methods employed by manufacturers to make exhaust notes sound sportier and the method varies from manufacturer.

Lets consider what a typical 2.5/3.0 V6 and 4.0 V8 exhaust system comprises. A twin pipe system is employed. Two manifolds are bolted, (one either side of the V engine cylinder heads) and then are both connected to two 50mm O/D downpipes each fitted with integral catalytic converters. Exhaust gases pass down the two downpipes, through the two catalytic converters and then through two bent 50mm OD extension pipes. The down pipes finish roughly under the foot wells of the front seats. That is the first stage of the exhaust system.

I`ll describe the S-type 4.2 naturally aspirated and the R supercharged system later.

Stage two, or the centre section of the exhaust joins to the stage one section under the foot well area. It comprises two parallel 50mmO/D pipes which include a short cross pipe set at 90 degrees between these two pipes. A hole is formed in each of the two pipes and the short cross pipe or balance pipe is welded to those two pipes. Think of this second stage part as looking like an elongated capital H. The balance pipe helps achieve a pleasant sound which does not sound uneven or lumpy unlike like a typical American V8, and assists with exhaust gas scavenging and exhaust flow balance from within the system. That second stage extends to roughly under the front of the back seats. At that point two round resonator exhaust boxes approximately 18" long are welded to the parallel pipe section. After that, another pair of 50mmO/D pipes exit the resonator boxes and the whole section finishes around the area of the differential.

Stage three is again made from 50mm O/D pipe. It differs from stages one and two in as much as this third stage is comprised of two large and completely separate long triangular shaped exhaust boxes. They hang as two separate units either side of the car behind the differential on rubber hanger loops which are suspended from the rear bumper beam mounted below the boot opening. The exhaust boxes finish again with 50mm O/D pipes which exit the car below the rear most extremities of the plastic molded "bumper cover".

The S-type R differs in as much as it is made through out in 60mm OD pipe to cope with an increased volume of exhaust gas produced by supercharged engine. A larger sectioned exhaust system is required in order not to restrict engine performance which would be the case if the small bore system used in less powerful models within the model range were used. I believe (and I need confirmation on this) that the 4.2 naturally aspirated model also uses 60mm OD pipes.

To return to the non supercharged exhaust standard OE system, V6 and V8 cars all share the same stage one and two system described above. However V8 models have visually physically identical rear exhaust boxes to V6 models but internal differences are built into the back exhaust boxes which are tuned for V8 models. Part numbers between V6 and V8 back boxes are different. As an example, fitting a V6 back box to a V8 may result in a rather strange sounding exhaust. Similarly swapping back boxes from a V8 to a V6 may also be unsatisfactory. Not a lot of people know that.........

Lets move on to how different manufacturers build sporty sounding and more efficient exhausts. Many increase the OD size of their system pipes. Fitting of a sports exhaust of large bore may require sleeve adapter tubes to join differing sized exhaust pipes. Manufacturers may decide to build a system which dispenses with OE type back boxes completely in favor of just simple replacement pipes or may also just replace the OE back boxes with smaller items or which have more efficient less restrictive pipe runs within.

The Club system retains the use of the first and second stages of a standard 50mm OD exhaust system as described above. The third stage of a standard exhaust is dis-guarded and two simple pipes wit small exhaust boxes take their place. Such a system will give a sporty sound but unless a larger OD system is fitted throughout the car, only a relatively small increase in power will result. The exhaust itself will remain almost as restrictive to gas outflow as a standard system. If it is the sporty sound you are after, then the Club system represents excellent value for money and on a 4.2 naturally aspirated model, for which the system was originally designed, an approximate increase of 7hp has been seen. Graham Searle has such a system fitted to his 4.2, as does James Blackwell`s brother on a 3.0 V6. Both with good results.

The Miltek system employs a different approach. This is a full blown system designed for the supercharged S-type R. It is constructed from 60mm OD pipe and is available either with or without resonator boxes being built into the second stage of the system. Fitted with resonators, the system is rather quieter than without. The third or rear most stage of the exhaust employs back boxes which are visually almost identical in size and shape to OE items. Internally, restrictive pipework (bends, turns and sound deadening are reduced) which result in a loud, deep and distinctive V8 exhaust note. Such systems are commonly marketed as "cats back" systems ie only the middle and final stages get fitted to the car. Manifolds, cats and downpipes are retained as standard. Sports down pipes and catalytic converters are available to further increase performance but those further mods would cost a further £2k. However power does increase.

Miltek systems are particularly good if the car has other tuning modifications such as an ECU upgrade, a free flow air filter, manifold and or cylinder head modifications. The Miltek fitted to my car gained around a 10hp increase in power with an ecu upgrade giving another 25hp. My car is a 4.0 V8 and required sleeve adapters to be fitted to allow standard OD down pipes to marry with the 60mmOD S-type R system to be employed.

The secret with fitting any modified system it to do research before buying. Always ask the manufacturer of a favored system is suitable for your model of car. Particular attention should be paid to pipe sizes and whether adapters are required. An S-type exhaust is big, heavy and unwieldy. Fitting on a four poster ramp is recommended. Old systems can be a devil to remove. The chap at Paramount where I had my Miltek fitted struggled to get my old system off the car in complete units. I wanted to keep the old system as a spare. In most cases a fitted will just cut the old system off with a gas axe and dispose of as scrap. I had to be awkward and keep mine!

Perhaps some of this information may be useful to those wanting to fit a different exhaust to their car.

Mike

[latebreaker]

Thanks for the knowledge Mike.

What products do you recommend to clean the exhaust tail pipes?

Krish

[J44EAG]

I`ve used a nylon pot scourer with white spirit or other oil soluble thinner, finishing off with some rubbing compound on the polished chrome parts.

I suppose if you are really keen you could clean the internal accessible part of the tail pipe with a bottle brush and thinners. If you have a great big exhaust like mine, you could use a toilet brush! Don`t blame me if you get it stuck in there though!! Could look pretty daft with a pair of bog brushes stuck out your exhaust over Christmas. The Old Bill might have a good excuse to pull you. Explain yourself out of that..........

Mike

[latebreaker]

Thanks Mike.

Reference your bog brushes.....sounds like a scene from a Carry On movie

Krish