Mrfiat's fiat 131

[HQ355]

Looks like some nice gear there, how many "killer wasps" are you hoping for ? Keep up the good work !

[delcowizzid]

nice h-beam rods going for reliablity

[Holden202T]

I guess the question about the regulator can be answered two ways .... you can either get massive injectors and not need to change the reg or you can get borderline big enough ones and screw up the regulator pressure.

when I started with my turbo motor I was using the stock VK EFI regulator with no problems, however as the engine developed I soon found I was on the limit of pump and injectors so I fitted 2 pumps and the adjustable regulator to get just that little bit more from my system.

[festy]

That's coming together very nicely I knew you'd get yours finished way before me...
Did you do the welding yourself? Is that intercooler one of those ebay 280mm jobs?
How much boost are you planning on? Even with only a couple psi that's going to be a bucket load of fun

Your injectors are pretty big, something like 34lb I think so you might get away without changing the fuel setup if you're only chasing moderate amounts of boost.
I think the donor car was a 2.3L turbo 4 that ran something around 8-10psi boost at a similar rail pressure to the N13.
Higher fuel pressure puts more stress on fuel lines, clamps etc so IMO don't run a higher pressure than you need to.

Maybe you could fit a weak (4psi?) wastegate spring and run an electric boost solenoid from one of the ECU flex outputs, triggered by MAP vs AFR to let the ECU control boost, as well as provide a safety net in case your fuel system can't keep up.

[mrfiat]

Looks like some nice gear there, how many "killer wasps" are you hoping for ? Keep up the good work !

If i can get around 190-200 KW at the wheels, id be happy!

nice h-beam rods going for reliablity

Cheers, that's what im hoping for

That's coming together very nicely I knew you'd get yours finished way before me...
Did you do the welding yourself? Is that intercooler one of those ebay 280mm jobs?
How much boost are you planning on? Even with only a couple psi that's going to be a bucket load of fun

Your injectors are pretty big, something like 34lb I think so you might get away without changing the fuel setup if you're only chasing moderate amounts of boost.
I think the donor car was a 2.3L turbo 4 that ran something around 8-10psi boost at a similar rail pressure to the N13.
Higher fuel pressure puts more stress on fuel lines, clamps etc so IMO don't run a higher pressure than you need to.

Maybe you could fit a weak (4psi?) wastegate spring and run an electric boost solenoid from one of the ECU flex outputs, triggered by MAP vs AFR to let the ECU control boost, as well as provide a safety net in case your fuel system can't keep up.

Yes all the welding was done by myself using a mig. The intercooler is just a generic ebay one..not sure on exact dimensions but its about 300 long.
Since im running forged pistons & rods as well as bigger head bolts and a MLS head gasket im hoping to run around 15psi..maybe even up to 20, so i think larger injectors are a necessity.

[HQ355]

That should pull like a school boy in a little fiat !

[festy]

Since im running forged pistons & rods as well as bigger head bolts and a MLS head gasket im hoping to run around 15psi..maybe even up to 20, so i think larger injectors are a necessity.

umm... yes. Might want to think about upgrading your pump and fuel lines too in that case
(and your brakes, and life insurance )

[mrfiat]

Since im running forged pistons & rods as well as bigger head bolts and a MLS head gasket im hoping to run around 15psi..maybe even up to 20, so i think larger injectors are a necessity.

umm... yes. Might want to think about upgrading your pump and fuel lines too in that case
(and your brakes, and life insurance )

Ive changed the fuel hard lines to ones i pulled from an Audi, ill be buying a Bosch 044 and will get some injectors around 600cc +
Ill be modding my fuel rail to take an sr20 DET fuel pressure reg, It bolts to a flange at the end of the rail. (currently have a crudely welded on hose fitting that im keen on removing) and that should take care of my fuel system.

The head has been bolted on and timing belt fitted, wont be long now..

20150218_200951.jpg

[festy]

I knew you'd get yours finished way before me...

...and he did

I went over to mrfiat's place last weekend to help with an initial tune.
A quick poke around the engine bay to make sure everything was in order, then on to the ECU.
First we upgraded the NVRAM to 12P v1.1.2 and migrated the cal, then set the injector flow rate for Deka 60s and 2 bar MAP sensor flags.
We pretty quickly worked out that the 2 bar sensor was actually a 3 bar, and after a few minutes road tuning it became apparent it was really a faulty 3 bar sensor... halfway through a roundabout it gave up completely, so we limped back to the garage.
I'd brought a few random spare parts along with me, and luckily that included a 3 bar sensor so we swapped that in, and it made a bit of a difference - here's the faulty sensor being swapped out:

bad_map.jpg

We started working on the tune, but something clearly wasn't right... it turned out to be a faulty wideband so we called it a day.

Yesterday we tried again. After a lot of mucking around getting my wideband swapped in, we went out and tuned the 20-100kPa VE on some quiet backroads.
Once that was looking good, we moved on to tuning the boost - pretty much following the Advanced Tuning Guide for the initial setup and starting at about 7psi until the AFRs were well under control, then raised the boost to 11-12 psi and continued to fine tune.

We did hit one minor tuning issue. It pulls very nicely in 2nd, but a quick shift into 3rd caused hesitation and was slow to make boost, sort of just bogging down more than expected.
The turbo surges a lot, so to see if that might be the cause we tried a slower 2nd-3rd shift and that was much better, so maybe it just needs a BOV to stop the turbo from getting hammered?
The injectors have a bit of headroom left, they're getting all the way up to 40% DC at 5800 rpm but I have a feeling that once the engine has a few more kilometers on it, mrfiat might want to re-visit the boost limit so it'll be good to have some capacity in reserve there...

I thought this was an awesome little car in NA form, but it's seriously fun now

[vlad01]

yeah would like a bov, soulds like the turbine is being stalled, hence the big lag.