Over-run noises

[BeanCaker]

As a new Griff 500 owner (new owner, not new Griff), could someone tell me if exhaust popping on the over-run is normal for a cat engine? I got the impression that only the older pre-cat cars did this. Sounds great, but concerned that the cats may be cruising for an expensive bruising.

[DIGGA]

I've had a non-cat 4 litre Griff, and now have a Griff 500, both of which pop & bang on the overun. The 4l seemed to do it more - not sure why, though I suppose the cats must muffle some of this out. When I got the 500, I was slightly dissapointed with the overall lack of noise(s) compared to the 4l, so I had the silencers removed and it sounds great[i] now. So, yes it's OK and if you like it (and fancy more racket) get the silencers gutted! Which brings me to a relatd point - does anyone know whether this popping\banging is accompanied by flames exiting the exhaust? If not, how can one achieve this spectacular waste of fuel? Marcus & Ocean Haze Griff 500

[Saturn 5]

My 500 does that, I wish it made as much row as a non cat car, never mind. It still sounds rather nice.

[Midnight Blue]

My 500 also does that, I'm sure all that unburnt fuel can't be doing the cats any good! I'd like a louder exhaust, but I get on with my neighbours well and it's noisy enough at 6am. There's also MOTs, track days and headaches on long journeys to think about.

[trefor]

I thought popping on the overrun, usually done with part throttle in my 4.0 Chimaera (catted) was a standard feature on Rover V8s - ideal for trundling through sleepy French villages in third early on a Sunday morning.

[graham]

>>My 500 also does that, I'm sure all that unburnt fuel can't be doing the cats any good!<< well take em out then. you get a much better noise but not that much louder, and combined with a rechip better response and flames on the overrun. you just need to find a friendly mot garage.. one a year or run one thats less than three years old. my exhaust looks standard so if i ever get pulled and tested well they must be knackered then...

[apache]

if you alter the back box you get loads of popping and rumbly like noises, not louder just better and as this is after the cats it wont bugger them up....cheap to do too

[GasBlaster]

Apache Pray tell more! How does one alter the back box? Cheers GB (Silver Griff 500)

[EdT]

quote:if you alter the back box you get loads of popping and rumbly like noises, not louder just better and as this is after the cats it wont bugger them up....cheap to do too

..here comes another one!..

[philshort]

My decatted Chim 500 makes an excellent racket on the overrun, especially with a light application of throttle. Must add a bit of juice to the mix, backfires like buggery. I can't help acting like a complete arse sometimes, driving round town in 2nd just so I can get it to pop and bang. Childish behaviour! Don't know about the flames, must get someone to drive past in it so I can check it out.

[apache]

gasblaster, remove exhaust, cut around rear of can and pull off twin tailpipe bit. get two bits of pipe the same diameter as the internal diameter of tail pipes and the same length as the silencer push fit them in, replace the rear of the silencer and weld back together. Remove the electrical connector to the ecu and refit to redatum the ecu. Remove all small children and others of a nervous disposition and fire it up, all the loosened carbon will pour out and you will grin painfully

[GasBlaster]

Sounds like a job for a man who knows what he's doing! Not me, then...

[edward]

take it your still pleased with the noise then Apache!?

[apache]

I sometimes park the beastie on the lawn in front of the house, back to the front door which was open. I was watching the telly with the windows open and the missis fired it up for a raid on tesco's.....won't do that again, scared the **** out of the cat too

[EdT]

yeah - good isnt it!

[EdT]

like those wheels BTW Ap. - easy to do?

[apache]

yeah a doddle, had to fit a couple of 3mm spacers as they rubbed the bottom wishbones but work great now.....not looking forward to reshoeing it tho

[EdT]

Apster - I'm trying to get along to the Abingdon sprint 25th Aug (as a viewer)and dragging a few pals with me - just convinced one to trade up to a V8S! - fancy popping along & showing those wheels off? THere's always our yet to be run 'sound off'!!>>

[apache]

Ed, not sure, sposed to be going to Santa Pod that weekend... I'll keep you posted