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Decat system

Timberfake

Timberfake

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Location
newport
Car
Accord v-tec s
Just had a decat and back system put on today and number one its too loud and I. Asked for a mid sport and two the vtec seems to have disappeared or is it just being shadowed by the exhaust?
 
Hey dude,

First thing i'd do is take it back to the place that fitted the system. I ***ume it's a custom jobbie? By a company like Powerflow? If it is a custom job then the place that fitted it should replace it free of charge. The silencing of the exhaust is done by the back box, and the cat. I can't remember though if the, forgive the phrase 'normal 6th gens' (sorry - that sounds really condesending) have a seperartate silencer somewhere between the backboxes and the cat.

If not argue the toss that it's not the sound you asked for. ***uming of course that you asked for the noise to not be deafening. If you're a PITA then most companies will do what you want :lol:

With regard to the Vtec, there are 2 senarios.

1 - The Vtec is being drowned out by the exhaust - Do you have an induction kit fitted? If you do, then open the driver window fully, stick your head half out, and listen for the change in tone when you hit Vtec. I would recommend doing this in 1st or 2nd gear :lol: :lol: :lol:

2 - Becuase of the decat, there is no longer enough back pressure in the system to make Vtec as noticable as it was with the standard system.

Hope this helps dude.
 
The 'normal' ;) 6th gens do have a centre silencer, just before where the T section would be on an ATR exhaust. I thought the rear and centre silencers removed different frequencies? At any rate as above best bet would be to take it back, you've paid them to build something to a specification, if it doesn't hit the mark then they should make good the job :) would love to see some pics btw, I need inspiration for my exhaust!
 
If you're not happy, take it back man. But bear in mind just how important back pressure is on a naturally aspirated. Especially if it's a K20 or K24 (seventh gen) engine like yours. Back pressure and swirl is so important to the K series. You remove the cat and/or put too wide a pipe on and you could actually just be sapping the power through lack of back pressure. Sorry, just realised this is obviously in the 6th gen section. Still, take it back and consider the back pressure reducing the VTEC kick.
 
Yeah I asked for a mid sport which was described as a little rumble when you start the cat but won't really make any noise unless you put your foot down.. And I do have cai fitted which sounded amazing when foot was down thought that wifh straight through system would be spuffing. They did say that it will mellow over next couple of weeks but it would have to be drastic before its quiet enough. I did have interchangeable decat pipe put on so could change that my self in time only been out in it to take boy to party will give it a couple of blasts today..
 
Does the Vtec kick in when you rev on the spot or does the car have to be in motion??
 
Timberfake said:
Does the Vtec kick in when you rev on the spot or does the car have to be in motion??
Click to expand...

I'm not 100% sure, but I think you need to be rolling. I don't think VTEC engages when you're in neutral. I could be completely wrong though.
 
my 6th gen used to rev through to the limiter in neutral, but the k24 engine stops at 4,000 ish revs. I guess your vtec would engage in neutral, before the days of saving the planet etc! ;)
 
whereami said:
my 6th gen used to rev through to the limiter in neutral, but the k24 engine stops at 4,000 ish revs. I guess your vtec would engage in neutral, before the days of saving the planet etc! ;)
Click to expand...

I'm pretty sure mine goes past 4K in neutral. Messing about with mates I'm sure I've done it. Maybe the VTEC doesn't engage though. Or maybe it did stop at 4k. Oh, now I've just confused myself :lol: . I dunno...
 
VTEC won't engage in neutral, car has to be moving and in gear :)
 
Well gave it a blast earlier and I can see the revs change speed but not much of a kick and don't seem to be as effective but rang longlife back up this morning and said it's stupid loud and is now booked in next week to have it made quieter think they have to put a bigger baffler in I'll have them check the whole thing as it don't sound the best at all and I paid them £370 for it...
 
A bigger baffle will only make a difference if there is more material inside it to depress the sound.

Your car, when stationary will not engage Vtec, but will rev to the limiter (provided it's warm) but this is not recommended. It will rev, but as the car is not moving the Vtec lobes will not come into play in the engine.

You also have to remember that the vtec kick on the F18 or the F20 enignes is not all that noticalbe anyway.

Make sure you keep us up to date with the results from the place dude.

*edited due to REALLY poor spelling :lol: 8
 
I dont suppose u have a done a rolling road test, or plan to do one in the near future. Just wondering how many horses u have gained.
I'm contemplating on finding out how much it would cost to get to the 150bhp mark.
 
^^^However much a turbo costs :lol: :lol: :lol:

IIRC the 1.8 comes with 134bhp standard. WIth an induction kit, de-cat and mandrel bent 2.5" piping you'll be gaining 10bhp maximum....sorry dude.
 
c'mon man
dont say that
where's your accord spirit... :D

I was afraid of a such comment.
So no matter what i change/i will still be driving a grandads car at grandads speed :( :( :( :( nooooooo

well i guess, i can always tint the windows B)
 
Sorry dude. :( :( :(

Unfortunatly if you wnat some performance out of the 6th gen your bet is to buy an ATR. That's what i did. I spent soooo long looking at power upgrades for my F20 that i got fed up. An FI conversion will cost upwardsd of £4k, and an engine transplant to an H22A5 from a lude will be upwards of £2500 inc. the donor engine.

Your best bet is to lower, tint, wheels, induction kit and a pretty exhaust, and then enjoy the feeling of having a MUCH better looking, (and of course reliable) car than many that cost 3 times as much. B) B)
 
Got to agree with the above, I thought my 2 litre VTEC Accord was powerful when I got it, but after driving a car with a DOHC VTEC H series engine in, I realise it was no match. Saying that with an induction kit on it sounded fantastic, and I still think the 6th gen is a really sexy looking car considering it's 10+ years old now. And the whole time I've had it I can't say there's anything I don't like about it, it's a car I really love.

I'm currently swapping a H22A motor into my 6th gen as my F series gave up last year. I've only spent about £600 so far, but you have to bear in mind I have no time constraints so can do bits as and when by myself. I'm spending the next 4 days playing about and hopefully getting all the wiring sorted and maybe even the new block in.

At the end of the day though if you love a car enough you can do anything with it, so long as it's worth it to you. I'm constantly asking myself is it worth it these days :lol:
 
:( :(

I plan on tinting as soon as i get off the sofa.
Lowered my last car, and will not do it again.
Theres not much choice of alloys, unless u get a hub adapter
 
Have you tried all of the alloy wheel sites? I found a fair few nice looking sets, just have to have a nose around. I really want a white set of 5 or 6 spoke alloys, I think they'd look the nuts against the dark blue paintwork of my Accord
 
i tried fleabay, just put in 4x114.3, and it gives u pretty much all the ones that can fit us.
dont want new ones, too expensive.
I'm tempted to try and fit my old alloys from a Celica, but not sure which hub adapter i need.

Back to the tuning side,
Sure nowadays most people see tuning as a remap, exhaust and a air filter.
BUT what about porting the engine and manifold (or if not too expensive getting a 421manifold) and then changing some bits in the engine. Again, i guess it will cost a packet, or maybe not that much.
Engines today can easily withstand 100bhp per litre (1litre is just under 2pints :D )

I guess the reason why type-r produce more bhp is due to the uprated parts...or am i wrong, shall I hide behind the sofa he he he

BTW
Sorry for hijacking the topic
 
The difference between the H22s and the F series engines is a lot wider than most people think. Bore, stroke, angles, crank, ECU, DOHC, rods, pistons, compression ratios...the list goes on mate. A lot of people say that the F series are a destroked H22, so take from that what you will :(

There is a 4-2-1 mani available for the F18, but it doesn't give enormous gains. The ecu in the F series engines cannot be remapped mate, and tbh there really isn't much point. Unless you're gonna go for cams (i.e Bisimoto), port and polish the head then the amount of money you'd spend for the ECU and map and the gains you'll get is not worth it.

If you really want power, buy a Type R. You must also take into account the different chasis in Hondas with DOHC engines.

Have a read through this mate.

http://en.wikipedia.org/wiki/Honda_H_Engine
 
Sorry dude, forgot this

Specifications F18A

Bore × Stroke: 85.0 × 81.5 mm
Displacement: 1,849 cc
Valve Configuration: SOHC, 16 valves, VTEC
Compression ratio: 9.3:1
Max power: 138HP (103 kW)
Max torque: 124 lb·ft (168 N m)
OBD 2 Ecu
 
Well got car back today, haven't been out in it much but is a lot quieter and the vtec is back but asked them what they did and they said they have put a second silencer in the middle of the system, although this solves the problem i had with the fighter jet taking of sound i was getting and the vtec cross over being noticeable again i cant help but wonder that surely sticking another silencer in the system then defeats the whole idea of decatting it or will the silencer not restrict it so much???
 
Glad you got the sound you're after mate.

As for the noise, you should now have the same amount of sound deadening that you had with the standard system, so with the de-cat, you should feel the throttle response up a little than you did when the cat was in place. Obviously the best would be for the decat and no deadening, but that is not a - legal, and b - not practical. I've got the cat put back in my car atm, and there is far less rasp from the exhaust and is much more pleasant when driving a long way.

When you say the Vtec is back, do you mean the noise or the feel of crossover? If it's the feel then it's as i thought but wasn;t too sure of and the F series engines need the back pressure provided by the exhaust to give the Vtec extra feel.
 
the feel is back but not sure if its just me but it feels like it takes longer for the car to get up to vtec so have questioned the fact that having another big silencer defeats the object of having a decat system but they ***ure me that they use free flow silencers and that's hoe it can still be a sports system but quieter...
 
Josh2109 said:
The 'normal' ;) 6th gens do have a centre silencer, just before where the T section would be on an ATR exhaust. I thought the rear and centre silencers removed different frequencies? At any rate as above best bet would be to take it back, you've paid them to build something to a specification, if it doesn't hit the mark then they should make good the job :) would love to see some pics btw, I need inspiration for my exhaust!
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Looks nice mate, I like that it's quite subtle but still looks a lot sharper than the stock pipes :) is your car white by the way?! Mega jealous if it is lol :p
 
That looks brilliant Justin!!!! Very posh, but also understated. Very good choice of back box fella. B)
 
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