Its non turbo. It has a different gearbox and transfer box to the turbo and a few other bits, mainly built stronger for the turbo model
You can improve the power / torque by fitting a turbo inlet manifold
You will hurt power by putting a turbo intake manifold on a non turbo. The dual runner intake manifold on the non turbo helps with down low power. It will be an absolutely dog if you put a turbo intake manifold on it.
Ive seen threads where it was tested with dyno data and it improves low down at the cost of top end
I used a polo g40 (supercharged) inlet on a polo gt NA to cancell out the slump of the performance cam moving the powerband up
I appreciate that there will be a difference of opinion on something like this, but is there any definitive evidence either way ? also does anyone know what the internal differences are between the Turbo and the NA Intake manifold as the look virtually identical apart from the embossed lettering externally.
It absolutely kills down low power. Guys have tried it and put the na manifold back on.
Thanks for the info guys. I had a word with my mechanic. There is a lot that can go wrong when adding a turbo to a non-turbo NA engine.
The engine bay does have a lot room for improvement. To fit any kind of decent turbo kit, it will require an engine conversion.
An engine conversion is a big job and would typically take around 40 hours of labour. Then tuning is also another trial and error approach.
I was told that the single greatest improvement for power and torque is a turbo. I will be doing more research on Twin Scroll turbos for a V engine.
I think what some are referring to is ‘Turbo Lag’ at the lower end. This can be avoided by adding more bells and whistles such as aftermarket ECU, a wastegate or new air-intake. 
I think speculating is the easy part! Finding a mechanic that wants to do it is getting harder by the year.
If anyone knows any turbo specialists for v6 engines in the North of England that would be a great help!
Conclusion here, is that if you are going to try and add a turbo kit to a non-turbo, it is definitely easier to buy a turbo engine than convert one. Not impossible though! Just costly!
The N/A manifold has butterfly valves inside that are closed below 3k rpms to shorten the length of the intake runners and increase torque. They open above 3k rpms with a motor called the VIC to increase the length of the runners and give more power. Mitsi designed the car, I’d trust that they got the most out of the N/A and the most out of the TT
Thank you so much for the information, I was not aware there was that much difference between the two intake manifolds, I am assuming that the TT intake manifold does not have the butterfly valves, I would be interested to know if the inside of the two intake manifolds are similar internally with the exception of the fitting of the butterfly valves or if the internal design of the two units is completely different.
Would I be correct in saying that the TT manifold does not need the butterfly valves due to the turbo’s providing more pressure or have I got the whole principle incorrect
Correct the turbo cars don’t have a need for it. Some people have tried to use the NA manifold to be beneficial to a turbo car, but found it was actually a hindrance and hurt power on the turbo car.
The NA manifold just has 3000GT on it I think and the Turbo looks different as also has Twin turbo on it. Side by side they look different
No you can’t improve power by fitting TT manifold. It’s fake news.
You’ve got the whole principle incorrect.
Except I don’t. It’s been proven multiple times.
They’re actually quite different if you look at them side by side
Not to mention the driveshaft, rear diff and half shafts. It’s actually a huge job from what I hear. Personally, I’d just enjoy the NA in all its NA glory.
Okay, I take all advice onboard as personally, I haven’t put any theory into test yet. The following is what I have read and not what I have practised…
I would sure love to see some examples of similar experiments. Either failed or successful.
Although it is costly and in some cases dangerous to convert an NA engine, the GTO has a tone of space to add an air intake and turbo kit. There is a lot that can go wrong. Including your engine exploding if you put a turbo on an NA engine with a 10:1 compression rate.
So being cautious and planning it carefully is definitely the right approach.
The following checklist.
- fuel capacity
- intercooler
- compression ratio
- Careful mapping by aftermarket ECU’s
- octane oil consideration
You can grab some aftermarket turbos that come with their own manifold. Some even come with pre-mapped ECU programming.
Long story short, it is something to consider if you have the budget and the time. It is something you should definitely consult professional help with. This is aftermarket speciality after all.
Wow !!! a classic collectible in very good condition I must say, unfortunately a non-turbo model, but who cares right? so before there is any discussion on cutting this beauty apart just for her to be fast enough to out runs cops 
, give her a nice bath, clean her up from all that gunk, dirt, aluminium tarnish and rust which is actually hurting my eyes 
, restore her to factory condition with all new Mitsubishi OEM parts, get advice from Joe if you plan on doing it yourself, and then you will have a queen by your side with a very high after market value and then when you have enough money in your pocket go VR4 hunting, if your lucky, you just may find one out there with your name on it.
Cheers and Good luck 
You got it back to front. Long runners for low RPM and short for higher rpm