102 replies to this topic

[haggi961]

Mines a full 3 inch system, so I hope it's not possible. Could be a lifter. I'm sure once I change the oil it will go.

Edited by haggi961, 31 October 2014 - 11:31 PM.

[haggi961]

On my stage 2 i destroyed the cat on the 2.5"" tullet. On my stage 3 without cat i blow out the wadding of the tullett backbox within just a few trackdays and i need db killers.   Is anybody succesfully running that HSJ cat on a >300hp system? It may come to that expensive piece i'm afraid

Chrisuk is running HSJ cat and seems to be running fine with no problems.

[Exmantaa]

Mines a full 3 inch system, so I hope it's not possible. Could be a lifter. I'm sure once I change the oil it will go.

 

My mate swapped/timed cams and lifters 2 times before the crackedTullet mani was discovered...

 

Listen with stethoscope/screwdriver to the head; a ticking lifter would be clearly audible there.

[CHILL Gone DUTCH]

@ Haggie It could also be the balancer idle chain tensioner

[Dave H]

I have a 3" system on "Bargi's" car on test at the moment. We are putting some miles on it and a few track days to ensure there are no problems. It is cat free and comprises of a pre silencer and then a large silencer box 7" diameter. The system is very similar to the one I have on my own car but I have made the boxes slightly longer. It has a single pipe outlet. It was noise tested at Snetterton 89db @ 3000, 92 @ 5000 a few weeks ago. Hopefully Ray will be along shortly with some more feedback. Dave

[CHILL Gone DUTCH]

@ Dave H I would be very interested Dave And if the design can incorporate a manifold with longer free flowing collectors even better Also after 3"

[Graeme Lambert]

I have a 3" system on "Bargi's" car on test at the moment. We are putting some miles on it and a few track days to ensure there are no problems. It is cat free and comprises of a pre silencer and then a large silencer box 7" diameter. The system is very similar to the one I have on my own car but I have made the boxes slightly longer. It has a single pipe outlet. It was noise tested at Snetterton 89db @ 3000, 92 @ 5000 a few weeks ago. Hopefully Ray will be along shortly with some more feedback. Dave

 

Thanks for the information Dave.

 

Seems like decent noise levels. Of course it's the driveby that matters for most tracks, so be interesting to hear how Ray is getting on with all that.

 

Ray

 

Can I ask, if you were to make another one, would you need the car there or could you fabricate it and send it to me for fitting?

 

G

[The Batman]

How much is a dave h exhaust 3" sc system

[Graeme Lambert]

How much is a dave h exhaust 3" sc system

 

You me and Chill on a group buy Joe?

 

Once you stop buying pets instead of car parts of course... (it'll be kids next mate)

 

G

[The Batman]

You can't buy kids did you never hear the birds and the bees story exhaust Na im good with my 2bular but always interested to know prices

[Graeme Lambert]

You can't buy kids did you never hear the birds and the bees story exhaust Na im good with my 2bular but always interested to know prices

 

No, but some things you've got to figure out for yourself right...

 

I had heard a rumour on price, but need to check myself to be honest. (it was relatively cheap compared to the established competition)

[Mangham54]

And having seen DaveH's work before the welds will be proalloy pretty.

[haggi961]

@ Haggie It could also be the balancer idle chain tensioner

Shouldn't be I hope as I had them all changed a few year ago when I had the conversion done. Im sure if it's chains then the noise would be there all the time as this goes once warm.

[CHILL Gone DUTCH]

Not chains The chain tensioner

[Bargi]

Let me first say having spent spent time with Dave fabricating and fitting a complete new exhaust system I can completely understand why exhaust shops shy away from working on the VX. A combination of things like lack of space, age of cars/condition and removing the rear clam make for a long day and lots of interesting challenges.

For 3 inch systems I saw the options were Tullet or 2bular. Between failing cats and noisy exhausts with Tullet and 2bular/Jim too busy with other projects I contacted Dave. This was also based on the previous VX work Dave had done and he was also a VX owner (well 3 actually! greedy bugger)

The big unknown was Dave's work had been with Turbos which don't have the noise issues like the supercharged cars do. Ultimately I wanted a 3inch exhaust I could run on a mid to high 90's DB track day without needing DB reducers, but also not need earplugs on long distance drives. Dave obviously couldn't guarantee the noise levels but I accepted this and worst case we'd end up with some DB reducers like other systems.

Upon arriving at Dave's workshop I was blown away at what I can only describe as the ultimate man cave for car nuts. There is everything from the 4 post ramp, various lathes and other tools to fabricate everything from panels to bespoke parts. Have a look at some of his Austin Healy work and you'll see what I mean http://www.davehardwick.co.uk/

Before starting any serious work we wanted to try out the exhaust system to check it could at least quieten the unruly SC.
So up on the ramp, downpipe off and let the fun begin

We had a DaveH pre-silencer, DaveH Backbox and a 2ubular backbox to try in various orders/combinations.

Results!
- Pre-silencer made the biggest difference by far, just by itself was especially more effective than either backbox (by themselves) at reducing the harsh mechanical noise.
- In combination with the DaveH backbox the noise levels came down again to a nice low note.
- In combination with the 2ublar it was louder and had more of a higher raspy note about it, especially when reved.

 

Funnily enough when you put the backbox first and then the pre-silencer it was noticeably louder than the other way around for both backboxes. I'm guessing there's some harmonics or something going on for this, but that's well out of my knowledge

 

For those who care about weight, the 2ubular backbox was a lot heavier than Daves and I reckon heavier than the pre-silencer and backbox combined. All the weight seemed to be in the final exit pipe.



Happy it would make a difference we went ahead and removed the exiting Milltek/Standard manifold and moved onto fitting the new setup. I went with a Tullet 3inch exhaust manifold as I hadn’t heard of them failing. It was at this point we discovered the Tullet exhaust manifold was going to require some "modification". As you can see in the photos there was no way a nut was going on. You would think after all these years they'd have it right, but there you go. Bit of hammering later and we're all done!


Tight fit!.



Then what followed was a lot of positioning, fiddling, repositioning, tacking, welding and repeat

Just realised I don't have any of the whole system together off the car, hopefully Dave does..

Test of the static noise levels compared to the Milltek and very impressed, especially at 3k where it's 3dB down on the Milltek. (last number is peak dB with a rev to redline)


Since the fitting in June I've covered about 2000 miles and no noticeable change in note or sound level.
On the road the exhaust is great, cruising it's no louder than the Milltek was, but when you step on loud pedal you know it's not the Milltek anymore
It doesn't have the raspy farty sound you sometimes get from some VX exhausts, sort of a beefier sound.
I'm at Donnington Sunday which is a 98db day. Also will stop around and have another proper check of the sound levels with Daves dB meter.

Really can't fault Daves work and would definitely recommend him to people. Hopefully all going well in the long term with mine we will see more of Daves exhaust on VXs.


Dyno results from just before Snett (and before I realised the air filter needed cleaning )

[CHILL Gone DUTCH]

Does Dave have a kettle on his workshop if so I would like a exhaust

[CHILL Gone DUTCH]

I also don't mind be a bit of R&D if it's required

[ArticMonkey]

Good write up.

[MartinS]

I noticed Graham at one point says bugger the noise and that he'll tame it down for track. I would suggest you go in Techieboys car for a run. He kindly gave me lift back to the hotel at the National and it was a truly horrible experience (not because of Matt whos a jolly decent chap all round) but purely due to his exhaust system and being in his car is not something I'd want to do for more than a few miles.

I like a bit of noise but my car can be totally quiet when you want it to be and fairly rowdy when you don't. I cant really advise on what you need for 300 plus bhp though as combos seem to come together differently and I'm running a weird mix that involves a Thorney manifold, miltek cat and 2tubular 2.5 backbox and 250 bhp.

Bargis exhaust does sound right and I'm sure is well made, but you might want to ensure that the visible part of the pipes at the back are to your taste.

 

Martin S

 

[CocoPops]

I think we're all getting a bit older and yes, I like my exhaust noise but I would like to choose. So a silent system 90% of the time and a hooligan for 10%.