1.4 Fire vs 1.4 Tjet

[targa]

Hello guys,

I'm looking at possibilities for a custom turbo setup since we wont be getting the Tjet in this part of the world. The compression ratios are the only ones i could find under the changes.

Does the 1.4 Fire(Fiat India has no more details) in Grande Punto come with the same head as the 1.4 in the Tjet ?

I couldnt find any details on the exact specifications of the pistons or the conrods. Not sure if the crank used is the same.

Any information on these would help me a lot.

Thank You.

/Targa

 

[Eklipze3k]

I think the engine you have is the 1.4 8v, the one in the TJet if I remember correctly is the 16v SuperFIRE.

 

[targa]

its a 1.4 16v Fire thats on sale here ... produces 90 bhp tops ....

 

[fingers99]

Strange. It's certainly possible to turbo them, but all informed wisdom is that the 1.4 16v N/A motor will throw rods if asked to produce more than 140bhp and that the gearbox will not stand the kind of torque such an engine will produce. It's a very different engine internally (rods, pistons, maybe crank......) to the 1.4 16v turbo fitted to the Abarth Punto and 500 and the Alfa Mito 155, which use a 5 speed box.

I'd guess that the 90bhp is a result of a re-map -- maybe to use lower quality fuel? But as far as I know, the Punto ecu is not reprogrammable by outsiders (no-one has the codes) while the one fitted to the N/A 500 1. 16v is.

 

[tim1989]

I'd guess that the 90bhp is a result of a re-map -- maybe to use lower quality fuel? But as far as I know, the Punto ecu is not reprogrammable by outsiders (no-one has the codes) while the one fitted to the N/A 500 1. 16v is.

Mines maped but you might be talking about the grande?

 

[fingers99]

Mines maped but you might be talking about the grande?

Well, the OP is. The Mk2 is easy peasy.

 

[targa]

It is the Grande Punto and i'm looking at a low boost setup. Around 120 bhp. Will the stock internals hold good for such a mod esp since the compression ratio is 11:1 as opposed to Tjet's 9.8:1 ? Want good low end torque, not really interested in high end speeds.

Moreover, the gt20 from the Tjet(rated 140 to 260 bhp) will not be used. Probably a gt15 (rated 100 - 200 bhp) to fit the low boost need. Planning to use a standalone ECU but then again getting the maps is another wild goose chase.

 

[fingers99]

120 should be fine, but it's well within the capabilities of a n/a 1.4 16v (decent manifold and exhaust, better cam, Rover K series throttle body, aftermarket ECU) which will be faster point to point than a turbo of the same bhp. I'd want some way of reducing the CR way below 11.5, maybe 8.5 max.

The GT15 -- in some formats -- is too small even for a 1.1 8v turbo. You get no lag, but a really nasty torque spike and it runs out of serious grunt about 1,000 rpm too soon.

 

[targa]

120 should be fine, but it's well within the capabilities of a n/a 1.4 16v (decent manifold and exhaust, better cam, Rover K series throttle body, aftermarket ECU)

These are hard to find here. I'll probably have to import them. Not sure of the cost but i'll have to pay significant import duty and wait for ages to get them from the postal dept. However, would you be able to direct me to any website that has them for sale ? or make details so that i can inquire around here ?

I'd want some way of reducing the CR way below 11.5, maybe 8.5 max.

If this is a must then i'll have to swap the internals for tauter ones. If thats the case, i'll go with low to medium boost setup since i'll have to rip open the engine anyway.

The GT15 -- in some formats -- is too small even for a 1.1 8v turbo. You get no lag, but a really nasty torque spike and it runs out of serious grunt about 1,000 rpm too soon.

Any clue what rev range gt15 is effective in ? Any other turbo you'd suggest for a low end grunt application (winding roads with small inclines)...

 

[fingers99]

These are hard to find here. I'll probably have to import them. Not sure of the cost but i'll have to pay significant import duty and wait for ages to get them from the postal dept. However, would you be able to direct me to any website that has them for sale ? or make details so that i can inquire around here ?

I don't know what's available over there, but someone you might like to get in touch with is Peter at GSR. He has, I think, some contacts in India, and a lot of experience tuning and sourcing parts for the FIRE and SuperFIRE engines. Contact details here -- "Performance FIAT" is essentially GSR's home webpage.

If this is a must then i'll have to swap the internals for tauter ones. If thats the case, i'll go with low to medium boost setup since i'll have to rip open the engine anyway.

The other alternative -- and it may be a cheaper one, if you go down the Turbo route, would be to import a complete engine/gearbox unit and -- if you like -- ECU from an Abarth Punto or Abarth 500. My guess is that either the Indian FIAT concessionaires, or FIAT UK would be able to do this for you. In the case of India it might even make sound commercial sense for them to sound out the market for the performance options. Otherwise you're going to have to get -- at least -- forged pistons and H beam rods made in the US or Europe.

Any clue what rev range gt15 is effective in ? Any other turbo you'd suggest for a low end grunt application (winding roads with small inclines)...

That's maybe the hardest choice to make when building a turbo engine. The critical part is getting the size of the components within the turbo correct, and the calculations are extremely difficult. The "GT15" part only refers to the external body of the turbo. So, many here have used the turbo secondhand from a Vauxhall Astra Deisel van -- which produces useful power from around 3.500 to 5,000 revs on a 1.1 8v FIRE engine -- it boosts early with little lag, but tails off rapidly, too. Others have experimented with GT17s and with the same body and different size internals. On the other hand, the Abarth 500 and Abarth Punto also use a GT15!

You really need a turbo specialist to get these features right.

 

[targa]

Thank You fingers99.

I think i have a contact who is in touch with Peter. Lemme confirm if this is the same guy you mentioned in the post. I've registered on PerformanceFiat just to be sure if otherwise.

FiatIndia is reluctant to go the perfoemace way since they had a bad whiplash last time when they were here with the old Palio (1.6 GTX). It had decent performance but was not well received partly due to fiat's negligence and partly due to people's obsession with Fuel economy. So, Fiat fled the scene leaving its customers stranded.

Now they are playing it safe. 90bhp on the 1.4 16v says it all. They are not interested in improving petrols since the market for them is very small. Against all odds, even if i persuade them to import me the abarth punto Engine and the gearbox, i'll have to pay the import and clearance duties that stand at 120%.
So a total price of 220% has to be shelled out. Thats the reason for my thinking of a custom turbo setup here. But, as it stands, even the 'technical guys' here at Fiat dealerships dont know a damn about the engines. Case in point, i have been chasing them for a Test drive 1.4 for over a month. Neither the dealer FiatIndia are showing interest. Reason given: None available since no decent market for Petrols.

I want low end torque to be good (winding roads with inclines) so that i wont have to shift to low gears as often. Hence the GT15. GT17 seemed laggy for such an application.

Finding an expert on turbos esp with the 1.4 is going to be a nightmare. I'm not sure how long i can keep up with this. Been over a year already.

Forgive me for this noob question: I didnt know we could choose the internals of the turbo. Arent they made specific by Garrett to suit the body ?

 

[fingers99]

No. If you can find a copy of a Garret catalogue, somewhere on line, you'll see that there are many GT15s, usually there are a couple of extra numbers tacked on to the end. Every vehicle specific turbo will have turbine wheels to suit that application. So, you can pull turbines off different GT 15 models to change how they respond.

More than this, the turbines themselves can be modified or the body of the turbo machined to take the turbine off a different turbo.

Good stuff on this in the A Graham Bell book Forced Induction Performance Tuning.