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kris450

Original Poster:

740 posts

223 months

Wednesday 5th November 2014
quotequote all
Hoping some kind hearted fellow/s could possibly help me out.

I've just got the car back on the road after a 2 year refurb, its been serviced and MOT'd (with no advisories) but something just doesn't feel right. I really can't put my finger on it, but in all honesty I was expecting it to feel quicker than it does. Perhaps I'm being optimistic, but after 2 years of running a 60bhp Pug 106 1.1 I was sort of expecting to have to recalibrate my driving to the expected step up in performance. Or was I expecting too much ?

Its also now fully decatted (original silencer + lambda's still in) and I'm hearing (what I think at least) is a sort of resonance/booming sound around 2000-2500rpm. Yes I know its going to be loud, but this doesn't sound like a good sound if that makes sense. I'm not sure if its just the decat allowing me to hear more than I did before or if something is amiss. No work was done on the engine so its not that I've taken something apart and failed to put it back together properly either.

Is anyone free in the Surrey area on Saturday for half an hour or so to verify if indeed there is a problem or if I'm just going nuts and all is ok ?

I'm more than happy to provide some beer tokens for your time and will travel to you. If not its not a problem, but I've invested so much money now I'm beginning to get a little paranoid that I've royally messed something up and am a little scared to drive it in case I'm doing more damage.

Thanks

Kris

phazed

22,466 posts

233 months

Wednesday 5th November 2014
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I'm in Surrey, pm me.

kris450

Original Poster:

740 posts

223 months

Wednesday 5th November 2014
quotequote all
phazed said:
I'm in Surrey, pm me.
Thanks Peter. PM sent thumbup

phazed

22,466 posts

233 months

Wednesday 5th November 2014
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None received as yet........

kris450

Original Poster:

740 posts

223 months

Wednesday 5th November 2014
quotequote all
I love computers frown

Just tried again.

phazed

22,466 posts

233 months

Wednesday 5th November 2014
quotequote all
Got a it and replied.

Dr Mike Oxgreen

4,466 posts

194 months

Thursday 6th November 2014
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I'd recommend getting a dyno run done at Surrey Rolling Road, now located at Farnborough in, er... Hampshire.

It's only £40 or £50, and will establish definitively whether your engine is under-performing. Even if it turns out to be normal, it's useful to determine a baseline of performance for your engine, and then repeat the test every couple of years to monitor for things like camshaft wear.

By doing this periodically (using the same rolling road each time), you can spot changes in your engine. Mine, for example, produced 276bhp when I first got it four years ago, but a year ago it was down to 264bhp. By putting the two curves on top of each other it was clear that the loss was only at the top end - typical of the early signs of camshaft wear. I'll be repeating the test soon, and if there's further significant loss it'll be time for a new camshaft when it's serviced in Jan.

keith2.2

1,101 posts

224 months

Thursday 6th November 2014
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Booming could be due to the removal of the cat in the y-piece, that's known to produce quite a "hollow" sound.

LordGrover

34,164 posts

241 months

Thursday 6th November 2014
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phazed knows his onions - he'll give a sound appraisal. yes

QBee

22,470 posts

173 months

Thursday 6th November 2014
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keith2.2 said:
Booming could be due to the removal of the cat in the y-piece, that's known to produce quite a "hollow" sound.
Depends how you decatted it- the Clive and ACT Y pieces make for a nicely agricultural sound, but no booming like you describe, whereas decatting the existing Y piece can create a sort of "dustbin" effect - as said above

kris450

Original Poster:

740 posts

223 months

Friday 7th November 2014
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Morning all

Apologies for not responding to posts yesterday, work was manic.

Car was decatted with a piece of art from Clive so its not the common 'booming' sound from an original y-piece thats just been emptied out. Went out in it last night and it actually feels a bit better. Perhaps its just the fact I haven't driven it in a couple of years...

Getting on a rolling road is a good shout and something I'll have to sort out soon.

Thanks for everyones thoughts.

Edit: I've just thought about a couple of other things actually. I understand its common for there to be a much stronger smell of petrol once fully decatted plus it should pop and bang quite a bit more. I'm getting neither of these things. Not sure if thats a symtom of anything or if the new exhaust needs to 'soot up' a bit (is that even a thing ?)

P.s. Peter, don't have access to my personal emails at the moment, but I try and give you call a bit later.

Edited by kris450 on Friday 7th November 08:33

caduceus

6,126 posts

295 months

Friday 7th November 2014
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I have just removed the main cat in my 4.5 and replaced with the ACT one. It is boomier but I don't mind it. I did my pre-cats first and drove a month or so before doing the main cat, and I still noticed the difference.

I'd say it's probably fine OP. As you say, it's more than likely because you haven't been in a TVR for a while and the sound difference is that pronounced. Whereas you have had the lot done in one go.

phazed

22,466 posts

233 months

Friday 7th November 2014
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kris450 said:
Morning all
P.s. Peter, don't have access to my personal emails at the moment, but I try and give you call a bit later.

Edited by kris450 on Friday 7th November 08:33
Use home, 01306 889135

Pupp

12,953 posts

301 months

Friday 7th November 2014
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caduceus said:
I have just removed the main cat in my 4.5 and replaced with the ACT one.
Well done Ged - how's it running? Load cooler under the bonnet for one thing I'd imagine...

blitzracing

6,422 posts

249 months

Friday 7th November 2014
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Which tune resistor are you running? You need the white in preference to the green, even without cats.

kris450

Original Poster:

740 posts

223 months

Friday 7th November 2014
quotequote all
blitzracing said:
Which tune resistor are you running? You need the white in preference to the green, even without cats.
Lambda probes are still in and connected up. I was under the impression no change was needed if you left it this way ?

blitzracing

6,422 posts

249 months

Friday 7th November 2014
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Thats correct- just checking.

caduceus

6,126 posts

295 months

Friday 7th November 2014
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Pupp said:
caduceus said:
I have just removed the main cat in my 4.5 and replaced with the ACT one.
Well done Ged - how's it running? Load cooler under the bonnet for one thing I'd imagine...
Hi Gary. I've not had a chance to give her a good run yet as been too busy. But she does sound angrier smile
The tune has changed slightly so may need to change ECU chip. But will give it a chance to settle down first. Need to go for a long run, and find some tunnels.

kris450

Original Poster:

740 posts

223 months

Saturday 8th November 2014
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Massive thanks to Phazed. Just popped round and after deducing that it was running on 7ish cylinders we tried changing the plug, the lead, had a look at the dizzy cap and nothing was wrong.

Then stumbled onto the idea that it wasn't getting any fuel and hey-presto ! The flipping injector wiring for no 1 cylinder had popped off... Once reattached all was well. What a difference driving home. Sound, feel and performance dramatically improved. Hugely relieved it was a quick easy fix. Not so happy at my own stupidity for not thinking of it before banghead. Never mind, at least its sorted.

Thanks Peter, really appreciated your help thumbup

phazed

22,466 posts

233 months

Saturday 8th November 2014
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You're welcome. Don't you just love the simple fixes!

Listening to you burbling up the road made me look in my empty engine bay...................grumpy