146 Decat?

[Damien_C]

I think the Cat is on the way out in my car as there is a funk smell when you drive on ie above 4k so is there anyone that does a decat for the 1.4 146?? Or do I have to make one up for it?

Cheers,

Damien.

[rafe005]

Went to powerflow for new exhaust and they cant even make me one so to de-cat it i'm having to do it myself. At least if the cat is knackered you can cut the flange off and just weld it to a section of pipe.

[symon]

If the cat is knackered just use a steel rod to remove its internals then refit the outer shell. You then have a de-cat that looks like a cat.

I don't think de-catting a TS has much affect though as it was originally designed for use with a cat, and hence the added back pressure in the exhaust is used to make the engine more efficient.

[Jim145]

I've decatted my Cloverleaf, and I haven't noticed any difference. Supersprint do one, though I don't know if it fits the 1.4

[rafe005]

Wouldn't there be more benefit to a de-cat if you were to have the car re-mapped as well?

[symon]

Originally Posted by rafe005

Wouldn't there be more benefit to a de-cat if you were to have the car re-mapped as well?

I think there is more to it than that. The valve timing, overlap as well as the tuning of the intake all have an affect.

I think a decat would make it sound better though.

[Jim145]

Yeah, the de-cat makes it sound raspy, almost a hint of my mates 1.7 sprint

[rafe005]

Well i'm going for a de-cat in conjunction with a powerflow system, force air intake, and then re-map so hopefully will have some effect, also looking into installing a turbo as well while all of this is going on so looks like i'm going to have some fun

[Jim145]

Sounds similar to what I've got. BMC induction kit, de-cat, Raggazzon group N stainless centre section (no silencers) Raggazzon stainless back box and a Squadra chip.
Are you going for a chip, or a custom set up? Like the turbo idea, sadly my funds wont allow

[rafe005]

Mine has the 32301 engine so cant chip, can only have a re-map, I'm making the turbo system myself. I have found a place in america that sells t3/4 tubos for about £140 and i'm mounting it under the car inline with the exhaust. Got the idea from an american company. I can sent you the links to their websites if you are interested in seeing what they do

[symon]

Originally Posted by rafe005

Mine has the 32301 engine so cant chip, can only have a re-map, I'm making the turbo system myself. I have found a place in america that sells t3/4 tubos for about £140 and i'm mounting it under the car inline with the exhaust. Got the idea from an american company. I can sent you the links to their websites if you are interested in seeing what they do

I think you would be better going for a T28 turbo than a T3, the T3 will run out of puff at around 240bhp whereas the T28 is good for 300bhp +
It will also require less boost pressure for the same power level due to being able to flow more air into the engine. The boost will also tail off less at the top end.

Because you are also running less boost pressure the lag effect will also be reduced, and you will get better fuel consumption, and less strain on the engines internals.

The Early 16VT fiats used a T3 whereas the 20VTused a T28 for example. My Nissan also runs a T28

If you wanted to fit a T25 there are loads on Rover Vitesses and 220 turbo's around cheap and quite a few in scrappies. I am sure the manifold could be made to fit as well. The T25 is good for around 250bhp.

Is gonna be a good project, good luck with it, and there is always plenty of support on here.

[rafe005]

I was looking at the T25's and 28's but was worried that they might be too big and might put too much strain on the engine. I have had a look at making a new exhaust manifold but there is bugger all room so the turbo is going to be mounted under the car before the cat (or where the cat would be) so I dont have to do too much work to the exhaust............I wonder how long the engine will actually last with a turbo......any guestimates?

[Jim145]

Sounds like a great project What kind of power are you aiming for?

[rafe005]

I'm not sure mate, really need to be careful so that i dont put too much stress on the engine, will prob just aim for around the 200 bhp mark....until i get bored, then might lower the compression of the engine so i can run more boost. dont want to run before i can walk.......or destroy my engine

[Damien_C]

I was tempted to smash out the cat but that can be dangerous, I found a decat there with a bit of searching.

Get a GT28RS if you want a T28 size turbo they are a ball bearing tubby with quick spool up time. One of the lads had one on his GT Starlet came on full boost at 3.5k and some whack off it, it was running a bar of boost was mad.

[symon]

I am pretty sure autodelta used a T25 on their 156 J11, I think a T25 is smaller than a T3 but is capable of spinning faster so flow rates are similar, though I am not 100% sure on this.

I am sure there are some compressor maps somewhere on the net.

GT28RS turbo's are around £600 new IIRC BTW that would really be the one to have as mentioned above.

[rafe005]

What i think i'm going to do is, as you mentioned before symon, get one off a scrapped rover and try and build the system on my audi (its on the drive not being used) as I've got to overcome a problem with the oil return as the return pipe will be going uphill if i mount underneath. Once I have the logistics of it all sorted and working on that I should easily be able to replace the turbo with a new one of choice and put the system on the Alfa

[rafe005]

Right, i have sorted out all the bits I will need for the turbo system i want to build, including a major headache regarding oil return but a scavenge pump should sort that....but I do have one really stupid question that no-one I have spoken to so far has been able to answer with any certainty and I know its a really stupid and simple question....but its one I have never asked (deep breath)........
Does a turbo activate at certain revs using internal centrifugal force or is there as external system controlling it?

[symon]

Originally Posted by rafe005

Right, i have sorted out all the bits I will need for the turbo system i want to build, including a major headache regarding oil return but a scavenge pump should sort that....but I do have one really stupid question that no-one I have spoken to so far has been able to answer with any certainty and I know its a really stupid and simple question....but its one I have never asked (deep breath)........
Does a turbo activate at certain revs using internal centrifugal force or is there as external system controlling it?

The turbo will activate itself due to exhaust gases going through it. However you will need to plumb the wategate actuator into the inlet pipework so that when boost reaches a certain level it will open.

As for oil feed, I think some people have teed off from the "clean" side of the oil filter pipework. You need to be very careful here though as if you remove too much oil flow you will starve the rest of the engine of oil. The return feed can be plumbed back in further downstream though I am not 100% sure on this.

[Damien_C]

One thing I forgot to ask about taking the insides out of the cat will that cause the exhaust to be changed drastically as on another site a fella said that it would but I am sceptical of this.

[symon]

Originally Posted by Damien_C

One thing I forgot to ask about taking the insides out of the cat will that cause the exhaust to be changed drastically as on another site a fella said that it would but I am sceptical of this.

It won't make a lot of difference, except to the emmisions.

[rafe005]

Well the plan is to feed off the oil after the oil filter as you said and to return it to the rocker cover. My biggest worry as I said was the oil pooling in the turbo at rest as the return pipe will be up hill but with a scavenge pump and a timer (so its carries on pumping for a minute or so after the engine is turned off) I should be ok for the next start up

[Damien_C]

Originally Posted by symonh2000

It won't make a lot of difference, except to the emmisions.

Bah the emissions don't bother me as there is a year left in the NCT on the car.

[symon]

Originally Posted by rafe005

Well the plan is to feed off the oil after the oil filter as you said and to return it to the rocker cover. My biggest worry as I said was the oil pooling in the turbo at rest as the return pipe will be up hill but with a scavenge pump and a timer (so its carries on pumping for a minute or so after the engine is turned off) I should be ok for the next start up

You could always fit the return pipe to the sump, that will mean the oil flows downhill. That is what happens on my nissan.

[rafe005]

as the turbo will actually be under the car (where one of the silencers is) it will still have to travel uphill. So just from a safety point its worth putting in a scavenge pump as they do on motorbikes