Technical Karolis Punto 75 Turbo project

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Technical Karolis Punto 75 Turbo project

Looking photos of cinquecento and seicento engines I noticed that the standard factory oil light sensor is different, and it has a bolt on the side. Could I take the pressure from there? On my Punto it's different, sensor straight bolted, not like this.

4f4426a662967_Mot.-Seicento-1.1-3.jpg


Maybe this could be simplier for me to get and do.

Mine is like this:

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I think Punto GT injectors are for me.

This is what I run, at least the auction said so, 250ccm at 3 bar. At 2.5bar rail pressure (standard in P75) they are on the edge for my setup at 0.8bar of boost. And I mean that, I know for certain that above this boost my ECU will start cutting injection times.
 
Makes no real odds. It's wise to retain the light whether or not you fit a pressure guage. So you need a tee anyway. (pressure guage/temp guage), although the temp guage is the really important one, IMHO.

Maybe I can't explain well myself :) I want to keep the standard light, but I was thinking about fitting oil pressure gauge there together with the light sensor.

Woj how do you made this? Or you don't use a pressure gauge?


For the injectors, hm, so for a 150 hp engine it needs a Gt fuel pump, right? Or some bigger injectors. Was also thinking about omega v6 injectors (like craigb), but with the info that I've got they seem smaller than gt ones.

What's the limit for the standard Punto75 injectors?
 
No pressure gauge in mine, no. I was planning to fit one and attempted even, but there was a problem in the plan. The pressure sender/gauge kit that I have (don't ask me the make, the box is long gone and the kit was actaully bought in Sweden for somebody else's different project) has two outputs, one for the dial (voltage), and one for the dash board light (on/off) so I wanted to get rid of the original pressure switch altogether. But the problem turned out to be the reveresed logic of the sender's switch, I could not be bothered to figure the whole thing out so I gave up on this mod. As fingers points, oil temp. is much more important, the pressure is either good all the time or not. Temperature is more of a moving target.
 
I would like to putting it on by the way. Just for monitoring if everything is fine.

Another thing that I can't understand if it's necessary to do something with the fuel pressure regulator or not. Standard Punto 75 regulartor is good for turbo job?
 
If it is not broken, then yes, it will work. Unless you want higher pressure on the rail.
 
Maybe I can't explain well myself :) I want to keep the standard light, but I was thinking about fitting oil pressure gauge there together with the light sensor.

I got that, but wherever you put it, I think you'll need a T peice as you've 2 gauges to add.

For the injectors, hm, so for a 150 hp engine it needs a Gt fuel pump, right? Or some bigger injectors. Was also thinking about omega v6 injectors (like craigb), but with the info that I've got they seem smaller than gt ones.

150 bhp is pushing the limits without forged stuff. The foxyemx/martin/donna cinq was showing signs of det (with much better than stock Mahle pistons) and breaking the odd driveshaft at less than that. It's probably no real coincidence that this car, and Craig's car have had the boost turned down to put out a mere 115bhp or so.

I'd not fit s/h pumps -- so, go 3bar and fit an insert that'll handle the flow rate you need. For the injectors, bosch type (for availability, price and fit) -- don't worry about what they're from, worry only about the flow rate.
What's the limit for the standard Punto75 injectors?

A hell of a lot less than 150bhp!
 
No, I would not say turbo is at its limit. I had a faulty WG for a while and boosting more incidentally, was working OK as long as the revs stayed low. What I suffer from mostly is too small IC, the fuelling system I can still play with a bit as well as boost. But I am guessing for my setup 140hp is the top limit indeed. Tricker had 134 on practically identical components, but polished head etc.
 
I got that, but wherever you put it, I think you'll need a T peice as you've 2 gauges to add.



150 bhp is pushing the limits without forged stuff. The foxyemx/martin/donna cinq was showing signs of det (with much better than stock Mahle pistons) and breaking the odd driveshaft at less than that. It's probably no real coincidence that this car, and Craig's car have had the boost turned down to put out a mere 115bhp or so.

I'd not fit s/h pumps -- so, go 3bar and fit an insert that'll handle the flow rate you need. For the injectors, bosch type (for availability, price and fit) -- don't worry about what they're from, worry only about the flow rate.


A hell of a lot less than 150bhp!

For the T, if I punt pressure sensor on standard position with standard sensor, and the temperature on lower hole near filter, I don't need a T.

For the hp, I would like to hit 150 hp, but 120 130 140 is good too. For the beginning I would like very low pressure (0,3 0,4 just for testing), so around 90 100 hp. I know 150 is becoming a high value, but that's not the most important thing. When everything will be done and working correctly I will try to put boost at 1-1,2 bar and see what happens and what power will come on. Now it's only an idea, not really important.

What are s/h pumps? In other words, I can use Punto75 pump or go for Gt pump?

I will run mainly on lpg, so fuel is important, but not the vital thing. Would like only to don't risk engine exploding by bad fuel system if will make some road on fuel instead gas.
 
No, I would not say turbo is at its limit. I had a faulty WG for a while and boosting more incidentally, was working OK as long as the revs stayed low. What I suffer from mostly is too small IC, the fuelling system I can still play with a bit as well as boost. But I am guessing for my setup 140hp is the top limit indeed. Tricker had 134 on practically identical components, but polished head etc.

I was under the impression you were getting excessive heat due to the undersized turbo rather than the undersized intercooler?

Was your wastegate playing up when you tuned to detonation on the RR?

Did you ever calculate the theoretical maximum output for your turbo using the compressor map?
 
For the T, if I punt pressure sensor on standard position with standard sensor, and the temperature on lower hole near filter, I don't need a T.

But you'll loose the warning light...........
What are s/h pumps? In other words, I can use Punto75 pump or go for Gt pump?

Second hand. Get a new one, they're cheap enough.

I will run mainly on lpg, so fuel is important, but not the vital thing. Would like only to don't risk engine exploding by bad fuel system if will make some road on fuel instead gas.

For LPG you need LPG injectors. It's certainly a better fuel than petrol.
 
You only generaly need a restrictor if running a ball bearing turbo. I've never investigated the turbo you're using (always been a garrett man myself) but doubt it needs a restrictor. I guess Woj can answer this question if he used the same turbo.

Isn't it the opposite way round? That's to say, by using a restrictor you increase the pressure, but reduce the flow.

Journal bearings rely on oil pressure to avoid metal to metal contact, ball bearings rely on volume (which is why you use ball bearings in 2 stroke motorcycle engines and gearboxen, rather than journal type bearings).

2 or 3 mm should be fine (but is about the internal diameter of a stainless brake line anyway).
 
Hmm. Doesn't make a lot of sense to me. I'd like to hear it from the turbo manufacturer's themselves.

Or, maybe, a restrictor increases pressure downstream of the restriction (think fuel pressure regulator). So the pressure in a journal type turbo is governed by the oil outlet?


I thought Garrett was a turbo manufacturer...

If there is a restriction it will be built into the drain of the turbo not the feed. Since generally we always talk about the drain being a big, vertical and as free flowing as possible it must be built into the turbo no. Restricting the feed will do nothing but stop the bearing floating and destroy the turbo.
 
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