Any T-JET tuner over here?

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Any T-JET tuner over here?

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What up folks? As you know I'm Brazilian and it's a pleasure to exchange experience here with you.

I'm about to buy a Bravo T-JET (it's very similar to the Bravo Sport T-JET 150 sold in Europe) and of course it's OEM condition isn't gonna last long. So... today's point is medium to hard T-JET tuning.

Head

First of all I'd like to know a few things about the head. The only T-JET engine fitting our Bravos is the 150 hp variant, that DOHC W/O Multiair one. I'm wondering what's the best one to tune: DOHC no-Multiair or SOHC Multiair? In general DOHC heads are way better than SOHC ones by providing a wide range of cam phasing tuning. DOHC ones use to provide more air flow as well. Other point is: as Multiair is a hydraulic system, wouldn't it fail at high revving? Does someone have an intake/exhaust CFM chart comparision between DOHC no-Multiair and SOHC Multiair heads?

I heard some rumors saying that StarJet's head has a better flow than T-JET's one... Is that right? What are the differences between them, the 1.2 16V FIRE's head and 1.3 16V's one?

Camshafts

What about them? I just know Colombo & Bariani's ones, is there other brand that builds (great) cams? What about Bariani's quality? Is the Road Max a good option for a 400 hp+ engine?

Valve train

Sh**! There's absolutely NOTHING about this one internet. I'd like to have titanium valve springs and retainers, but I can't find even ordinary ones! Nothing about valves (which stuff is better: Nimonic, stainless steel or there's another one? What about valve sizes?) and valve guides as well... I'm accepting suggetions. Remember that I want it to rev 8.5K+... Is there some brand that builds this stuff without special order?

Pistons and rods

AFAIK the original engine is able to handle about 260 hp and 360 nm, so I must buy forged parts. For pistons I heard about ProtoXide, Wössner and a greek brand called DP Pistons. For rods, I just know ProtoXide and EF-Racing ones. So which one is the best? Do someone know anything about their weight, reliability, quality and strength?

Bushings/bearings

Guess what? Nothing on the web once again! As the engine will have to handle a big stroke with small rods at high rpm's, what would you recommend me?

Turbo

This part is easy... I think! I'll swap the original IHI RFH3 into a Garrett GTX2860R together with a Tial QR 50mm BOV. What about the pipes? Should I keep it OEM? Intercooler... Any good brand/size?

Intake

I'm gonna order a special aluminium made manifold together with a new bigger bored throttle body. Wich TBi should I take?

Cooling

Will the original oil and water pumps together with the original oil and water radiators handle the new output levels? What should I do with them?

Cheers and thank you, have a nice week!
 
Camshafts

the cams from the star jet 90hp fit in the t-jet and it is like the road medium and you can get it way cheaper from a junk yard (y)

Valve train & Pistons and rods

ProtoXide and EF-Racing ones. add http://www.scara73.com/ to them but it costs alot

Bushings/bearings
http://www.scara73.com/ too

Cooling

Will the original oil and water pumps together with the original oil and water radiators handle the new output levels? What should I do with them?

they are handling my 200hp well i changer the intercooler with renault meguan rs
 
You won't get 400bhp out of a T Jet. You want the plain Jane 1.4 T Jet head -- it has better valves, better cooling, than the star Jet. GT2860R is too big.

Are you sure about that? I didn't tell this, but I'm gonna use Ethanol, which's AFR is way better than Petrol's: 9:1 against 13.3:1

Here in Brazil there's an endurance category sponsored by Fiat called Trofeo Linea. It's a single-brand competition and the engines' (T-JET) output is 270+ bhp with stock internals, head, valve train, valves... Everything. The only changes are the turbocharger, the intercooler and the injectors. And the use of Ethanol as fuel.

linea.jpg


So don't you think that using more pressure, forged internals, ported head etc. I'd get 400+ bhp?

Why don't you think a head porting is strictly necessary?

About the GTX2860R I made my calcs at not2fast and according to it and to Garrett's Compressor and Turbine Map it's gonna build it's full pressure (29 psi or 2 bar) at 5.500 rpm. Assuming that my engine's gonna rev to 8.500 rpm, that's a good turbocharger. At 2.500 rpm my turbocharger would be at 14.5 psi (1 bar) and at 3.500 rpm the former higher pressure (18.85 psi or 1.3 bar) would be achieved. I think that's a great choice, don't you? Of course I'd rather install a smaller turbocharger, but that's the smallest one able to handle 29 psi (2 bar) of pressure.

GTX2860R.JPG


Cheers!
 
Camshafts

the cams from the star jet 90hp fit in the t-jet and it is like the road medium and you can get it way cheaper from a junk yard (y)

Valve train & Pistons and rods

ProtoXide and EF-Racing ones. add http://www.scara73.com/ to them but it costs alot

Bushings/bearings
http://www.scara73.com/ too

Cooling

Will the original oil and water pumps together with the original oil and water radiators handle the new output levels? What should I do with them?

they are handling my 200hp well i changer the intercooler with renault meguan rs

Camshafts

Question is... Will they be enough?

Valve train & Pistons and rods

So the winner set is ProtoXide pistons with EF-Racing rods? Thank you for the site BTW.

Bushings/bearings

My greatest concern is that my engine will rev high! Do you think that their bushings/bearings are ready to handle something about 8.500 rpm?

Cooling

In Brazil is normal to find several 190+ bhp T-JETs and they're all like just remmaped ECU + K&N air filter + aftermarket intercooler (mostly from our Brazilian brand Supercooler). Some of them are equipped with an aftermarket downpipe as well and they achieve 210+ bhp and 300+ nm.

Dyno test:



Road tests:





We find some 240+ bhp T-JETs to, that are equipped with a bigger turbocharger, most of them with the Garrett's GT2560R.



All of them with stock pumps and radiator... But as my car will achieve 8.500 rpm and 400+ bhp I'm complaining about the high temperatures...

Cheers!
 
here you will find at the bottom of the english part the upgrades needed for 285hp i think it will be a must for you (though you can gt them from protoxide i refer for them for info)
http://www.scara73.com/web1/en/fiat...preparazione-motore-engine-preparation-3.html
i don't know about bushing and bearing my car already before completing the 35,000km and the auxiliary belt bearing is getting damaged and squeaking already
about cooling her in egypt the normal temp in summer is above 40 Celsius and i don't have any problems my father alfa in saudi arabia is 170hp gullietta witht the same cooling system and the temp there excuses the 50 Celsius most of the year
and i use water/meth injection to cool the car down
this post have alot of info
http://revlimit.forumotion.net/t32-topic
just translate it and enjoy reading
 
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I was discounting the ethanol, but it's going to depend a lot on the use of the car.

Folk have got very close to 700 rear wheel bhp out of the old Toyota 3SGTE (2 litre, generally stroked to 2.2 for strip use) (forged internals, cams, bigger valves, water/methanol injection, charge coolers, etc.) on mere racing petrol. But the chances of one of these being competitive with a 400/450 bhp car on anything but a drag strip are remote, even with an Ayrton at the wheel.

I would guess that the head design of the 16v Super FIRE engines is a limiting factor.

But, you'll need forged rods and pistons (maintaining the full floating pin design of the T Jet), bigger radiator, intercooler (or charge cooler), cams, valves, after market ECU, probably water injection, upgraded fuel pump and lines. And then, the other elephant in the cupboard may be the gearbox.

400bhp is a lot to get from an an engine developed from an engine originally slated for about 110bhp: it won't be cheap!
 
About the GTX2860R I made my calcs at not2fast and according to it and to Garrett's Compressor and Turbine Map it's gonna build it's full pressure (29 psi or 2 bar) at 5.500 rpm. Assuming that my engine's gonna rev to 8.500 rpm, that's a good turbocharger. At 2.500 rpm my turbocharger would be at 14.5 psi (1 bar) and at 3.500 rpm the former higher pressure (18.85 psi or 1.3 bar) would be achieved. I think that's a great choice, don't you? Of course I'd rather install a smaller turbocharger, but that's the smallest one able to handle 29 psi (2 bar) of pressure.

I'd think you might well get surge. Folk here and in the States like the GT28R series for MR2s making something in the region of 350 - 400bhp. But Garret themselves recommend that charger for engines with a capacity of 1.8 to 3 litres. (not sure in this url will work, but try turbobygarret. GT25R series would be the "mainstream" choice for a 1.4. Worth talking to Garret themselves.

Apropos the heads -- good headwork is always important, but FIAT's own literature on the T Jet highlights that they've paid attention to the cooling passages in block and head. (The head is different, the block isn't just a Star Jet with different deck heights). Exhaust valves (at least) are of better material.
 
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here you will find at the bottom of the english part the upgrades needed for 285hp i think it will be a must for you (though you can gt them from protoxide i refer for them for info)
http://www.scara73.com/web1/en/fiat...preparazione-motore-engine-preparation-3.html
i don't know about bushing and bearing my car already before completing the 35,000km and the auxiliary belt bearing is getting damaged and squeaking already
about cooling her in egypt the normal temp in summer is above 40 Celsius and i don't have any problems my father alfa in saudi arabia is 170hp gullietta witht the same cooling system and the temp there excuses the 50 Celsius most of the year
and i use water/meth injection to cool the car down
this post have alot of info
http://revlimit.forumotion.net/t32-topic
just translate it and enjoy reading

That one is a good link. That's a shame that the max output provided isn't that high.
Bushings/bearings are still a mystery for me... The higher the engine rev the quicker they wear! They must be strong...

Temperatures here where I live aren't that severe. In our hottest month (January) the average is 22.9 °C. In our coldest month (July) the average is 18.1 °C. And the anual average temperature is 20.5 °C, so it's not that cold and it's not that hot, it's... Mild! Hahahaha

But I'm still concerned about the cooling system...
 
I was discounting the ethanol, but it's going to depend a lot on the use of the car.



Folk have got very close to 700 rear wheel bhp out of the old Toyota 3SGTE (2 litre, generally stroked to 2.2 for strip use) (forged internals, cams, bigger valves, water/methanol injection, charge coolers, etc.) on mere racing petrol. But the chances of one of these being competitive with a 400/450 bhp car on anything but a drag strip are remote, even with an Ayrton at the wheel.



I would guess that the head design of the 16v Super FIRE engines is a limiting factor.



But, you'll need forged rods and pistons (maintaining the full floating pin design of the T Jet), bigger radiator, intercooler (or charge cooler), cams, valves, after market ECU, probably water injection, upgraded fuel pump and lines. And then, the other elephant in the cupboard may be the gearbox.



400bhp is a lot to get from an an engine developed from an engine originally slated for about 110bhp: it won't be cheap!



Ethanol use to be a great "helper"... Just by using it and tuning the ECU according the new fuel/spark times, it's normal to get between 15% and 20%, e.g. a Fiat Stilo Abarth owned by a friend of mine jumped from 170 bhp to 199 bhp, OEM top to bottom just by using Ethanol.



Great Toyota, huh? But as you said it's obvious that this one won't be friendly on the streets... And I'm nothing compared to our late Ayrton.



I've never seen a knocked down Super FIRE's or a T-JET's head... But I'm afraid it's CFM isn't that great.



Of course I'll use forged pistons and rods without forgetting the floating pins. The other parts that I didn't say anything I have already decided what to use, such as the ECU (I'm about to use Megasquirt MS3X), the fuel pump (maybe a Walbro or Aeromotive), spark plugs (NGK Iridium BKR9EIX), fuel/oil/water lines (Aeroquip) etc.



By the way, what about Magneti Marelli's ECUs?



I'm in doubt of which radiator and intercooler I should use... I know the gearbox (C635) won't handle this output but I think it's gonna get confusing if I say all about the car (suspension, gearbox, brakes etc.) on an unique thread, so that's why I'm talking just about the engine here.



It won't be cheap, I know... I'm planning spend something about £5,000/€6,250/U$8,500/R$19,000 just on the engine.
 
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I'd think you might well get surge. Folk here and in the States like the GT28R series for MR2s making something in the region of 350 - 400bhp. But Garret themselves recommend that charger for engines with a capacity of 1.8 to 3 litres. (not sure in this url will work, but try turbobygarret. GT25R series would be the "mainstream" choice for a 1.4. Worth talking to Garret themselves.



Apropos the heads -- good headwork is always important, but FIAT's own literature on the T Jet highlights that they've paid attention to the cooling passages in block and head. (The head is different, the block isn't just a Star Jet with different deck heights). Exhaust valves (at least) are of better material.



Maybe the turbocharger chapter will be the hardest one... I wish I could use a GT2554R or a GT2854R (that are very similar) but if I do this I'm sure both will overspeed when running at 29 psi (2 bar). I think you're a bit confused, I don't want use the GTX2867R, I'm thinking about the GTX2860R, recommended by Garrett for engines between 1.4 and 2.5 litres.



I knew that Fiat has spent lot of time reworking the head but I didn't know that there were differences between T-JET's and Star Jet's blocks... Is there some difference in the rod length (disregarding the materials)?



I will use much bigger valves... By the way which one is the best: Nimonic or stainless steel?
 
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. I think you're a bit confused, I don't want use the GTX2867R, I'm thinking about the GTX2860R, recommended by Garrett for engines between 1.4 and 2.5 litres.



I knew that Fiat has spent lot of time reworking the head but I didn't know that there were differences between T-JET's and Star Jet's blocks... Is there some difference in the rod length (disregarding the materials)?



I will use much bigger valves... By the way which one is the best: Nimonic or stainless steel?


You're right -- I did get confused about the turbos.

The deck height is different for the blocks (T Jet 0.8mm higher) but they're also different internally (for cooling -- presumably the water passages to the head).

Can't find anything on rod length, but T Jet crank is forged.

You could say nimonic is a variety of stainless. But, that aside, I'd go nimonic on that build.

Which ECU is better really depends on what features you need and -- more importantly -- what facilities you have available. The T Jet ecu (ar least, the early ECU as fitted to the Abarth 500) can be mapped given the codes, etc. But Megasquirt can -- in theory -- be mapped by any rolling road given a wideband ECU and a laptop.
 
Really? I thought Mega was way better tham the OEM one... Why is it worse?
motronic has more safe controller that have multi stage safety such as if the car over boosts it will try to reduce it by wastegate if it cant it will close the air intake butterfly
motronic change the a/f ratio map according to the intake air temp
it has alot of maps to control alot of things
 
motronic has more safe controller that have multi stage safety such as if the car over boosts it will try to reduce it by wastegate if it cant it will close the air intake butterfly
motronic change the a/f ratio map according to the intake air temp
it has alot of maps to control alot of things

Yes, but if you can't tweak the maps, it's no use on a car planned to put out more than twice the original power!

I can't think of an ECU that doesn't use inlet air temperature as a map parameter -- even. going back nearly 25 years -- the one on my old MR2!
 
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