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Discussion Starter #1
Hello

The Alfa GT's throttle body can be increased with either a Ferrari 360 or Ferrari 430 TB which is 84mm, together with the ACT Carbon intake Plenum you should get more air into the engine.

Now, If I get more air, I need more petrol to make a difference, so I would be needing hi-flow injectors as well with a good re-map to tell the ecu what to do with the extra air otherwise the whole mod is useless.

Anyone know what injectors the GT has standard and which to get for the extra air 84mm intake? Is this trial and error or has someone done both, air and petrol?
 

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With only a bigger throttle body + plenum there is no way you would need bigger injectors..... The standard injectors are perfectly able to cope with the, perhaps!, slightly higher air volume
 

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The OEM ECU is rather adaptable, It will adapt fueling to what the MAF reads. That is not the limiting factor. The standard injectors are bosch 0-280-156-038 = 224cc/min - that is good enough to 270 HP (202kw) at 95% duty cycle - you'll only need more if you go turbo route.

The intake runners are 45mm, so why would you want to go from 72mm TB that 2.56 times the area of the intake runner to the 76mm of the 360 - that makes it 2.85 times intake runner or 84mm TB that makes it 3.48 times intake runner flow area?

To make use of the bigger TB, you'll need to increase the intake runner size and the intake valve size, which means, you'll have to increase the bore, which means the 3.5 / 3.7 conversion, that you already know cost HUGE amounts of cash.

The plenum volume is 2.5L that comes from the 2.5L V6 - so yes to volume match that to your motor - 3.2L makes sense, but be careful of funny shapes that might cause the furthest cylinder from TB (#1) run lean while closest cylinder (#6) runs rich. The vacuum in the plenum might even cause the carbon to collapse a bit and become 2.5L in anyway...

We are still talking minimal increase in HP for a lot of money and effort.
 

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Discussion Starter #4 (Edited)
If done correctly we talking bout 18-20 hp increase with the standard TB and just the carbon fibre plenum and intake hose.

Best to just sell the Alfa and buy a Golf...this is supposed to be the cheapest and most gain mod of all.:furious:

So buying the ACT carbon plenum is a waste of money and sourcing the F360 or 430 TB is just as much a waste. What gives??
 

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If done correctly we talking bout 18-20 hp increase with the standard TB and just the carbon fibre plenum and intake hose.

Best to just sell the Alfa and buy a Golf...this is supposed to be the cheapest and most gain mod of all.:furious:

So buying the ACT carbon plenum is a waste of money and sourcing the F360 or 430 TB is just as much a waste. What gives??
Yes Aramis, we have all said it in a number of your threads that with an N/A car you cannot get serious kW increases with serious cash hungry mods. The same will be true with a N/A golf. If you want serious kW increase with medium/heavy money you need turbo
 

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Discussion Starter #6 (Edited)
Ok, so we are talking about Rotrex c38 (forced induction), who can instal something like the c38 in S.A. on an Alfa GT and looking at xchange rate and cost will also be over R 100,000 +
 

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Yes. Look at the 5.0 Mustang even ... You buy the 5.0 then you have a nice burbly fun car to drive. But if you want to upgrade performance you are looking at 5k USD +

Hellion Mustang Single Turbo Kit - Tuner Kit (05-10 GT) - Free Shipping

You could buy the 2.3 eco boost - and then you can increase the power on that % wise quite a bit for less money, but you will be stuck with a 2.3 and not a 5.0

You could buy a GTI and then:
1. aftermarket down pipe
2. aftermarket intercooler
3. aftermarket boost controller or Software boost control
4. SW tuning

The gains are decent, but still cost a fair whack of money - aaaaaand then you are stuck with a GTI that is as common as chips
 

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Discussion Starter #8
The gains are decent, but still cost a fair whack of money - aaaaaand then you are stuck with a GTI that is as common as chips
The F360 TB and 430 TB are a fair whack of money, combined with the whack for the ACT plenum and Autolusso carbon intake are another fair whack, now we already have a whole bunch of money, add 4 new tyres, Bilstein B12's suspension with Eibach ARB, the brake pads and discs if needed, more bunches of money for that so now we at a huge bundle of money...now we add the new non-cats exhaust manifold, s/s downpipes, catless s/s system to a Raggazon catback with quad outlets, re-chip everything on the dyno, many, many times, the cost of the chip, then even more bunches so now we have heaps of money and a whole heap goes into the main service, timing belt change with waterpump change, fitting of Q2, B12's suspension, new suspension bushes all round, de-rust what is rusted,now suddenly we have huge heaps and heaps of money spent and at the end of the day you have almost NO GAIN in hp/torque??
 

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The F360 TB and 430 TB are a fair whack of money, combined with the whack for the ACT plenum and Autolusso carbon intake are another fair whack, now we already have a whole bunch of money, add 4 new tyres, Bilstein B12's suspension with Eibach ARB, the brake pads and discs if needed, more bunches of money for that so now we at a huge bundle of money...now we add the new non-cats exhaust manifold, s/s downpipes, catless s/s system to a Raggazon catback with quad outlets, re-chip everything on the dyno, many, many times, the cost of the chip, then even more bunches so now we have heaps of money and a whole heap goes into the main service, timing belt change with waterpump change, fitting of Q2, B12's suspension, new suspension bushes all round, de-rust what is rusted,now suddenly we have huge heaps and heaps of money spent and at the end of the day you have almost NO GAIN in hp/torque??
More less, yes!

That's what happens with NA cars.

Your best options for increasing the power are to get it converted to a larger displacement or get a bespoke forced induction setup. Both options are incredibly expensive and hence why barely anyone does them.

Not really sure what your issue is?

You bought a NA V6 and there is only so much you can do to a NA engine to get more power. You might be able to pickup 25-30bhp with exhaust, re-map, cams etc. but you get to the point of diminishing returns.

If you're so set on more power you really just need to get it bored out or supercharge it (or both). If you don't want to do that, then be prepared to still spend LOTS of money and only pick up ~10-15% power increase.
 

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Discussion Starter #10 (Edited)
Yeah, I think I understand now. So my plan of action now shall be as follows:

Leave the engine alone, no point in spending on upgrades that do nothing, rather spend it on :

1. Decend suspension, B12's or Street-S kit, adjustable hieght, damping etc.
2. Eibach ARB kit
3. New brake pads and braided hoses, maybe new discs, depending.
4. 4 new tyres, either the same pirelli PZero's or F1 Assyms.
5. Raggazon backbox, just for the sound
6. Some eyecandy upgrades.
7. Full service, new timing belt, sparks, Q2 install.

Basically, leave the Alfa as is, upgrade suspension, brakes and looks.

After my TB clean and ecu reset, the Alfa is a new beast, it somehow found more torque, or maybe it is the "learning throttle" because all of a sudden I have more power at my toetips when I need it, it revs better at lower range, sounds better and pulls a hell of a lot better throughout the rev range, recommend for anyone.

I would love to supercharge the Alfa but I doubt I'd spend that much for a small vacuum cleaner at my inlets and I doubt anyone here has the knowledge to install it proper. In a perfect world small upgrades like supercharge or turbocharge shouldn't costs more than a small tract of land but hey, that's the world we live in. I might still look into NOS system, seems cheaper but again, knowhow is non-existent so I won't even bother. The GT is a naturally flippin fast car already, especially since my ecu reset and TB clean, I literally have to hold on to the steering wheel as I am pressed into the seat. Loving it :) and the ladies LOVE the Alfa already as is.
 

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But that IS the point of the gripe he has - that conversion cost more than the car's current value... :smash:
Any you're 'only' getting an extra 80bhp for that money too. A heck of a lot of money to spend for 80bhp. Hence why its best just to enjoy the engine as it is and enhance the experience with chassis and handling upgrades as OP seems to be doing now :thumbup:
 
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