5sfe Pistons, when we add a turbo... Options

[Neil_Y]

when 5sfe add a turbo, Do we need to change the pistion for the turbo running?

becase factory is for NA engine turbo need more accumulator groove,right?
and 1 question, if the compr. larger or smaller,what thats mean?
and i saw the aftermarket pistion from ebay.
Pistons from ebay.

This post has been edited by Neil_Y: Apr 28, 2009 - 4:49 PM

[Smaay]

Part #: SC7452 (5SFE Crank with 3SGTE Block)

those wont work, they are for a 3S-GTE block. stock pistons will be fine at low boost < 250HP

[_Jim_]

stock pistons will be fine at low boost < 250HP

I suppose the stock pistons are fine at those power levels. Supershannon77 has been running 285whp and 300ftlbs (thats 320+hp and 345+tq) for about a year now and still no issues.

The stock 5s has been proven time and time again to accept 15+psi without ANY issues.....It really should be just about written in stone that the 5s pistons are safe at 15psi and sub 300whp (remember thats about 350hp at the crank.)

[alltracman78]

^ Whadda YOU know about it?

[_Jim_]

^ JEREMYYYYYYYYYYYYYYYYYYYYY LONG TIME NO SEE MAN!!!!!!!!!!!

[lagos]

I think Smaay just rounded down to provide some basic ball park number. You cant pinpoint a specific horsepower number to each piston or a certain psi. It all depends on what turbo you use, how well you tune the car, and the current condition of the motor. Its silly to argue about minor details with stuff like this.

Neil_Y, no you dont need to upgrade the pistons or anything internal on the engine, however its a good idea to see what kind of shape your motor is in. If you have a lot of miles on it, or if its currently burning oil or has any other issues, it might be a good idea to rebuild it or swap for another engine thats in better shape.

[Neil_Y]

um.. just curious
bacause my 5sfe got turbo too.

[Neil_Y]

I think Smaay just rounded down to provide some basic ball park number. You cant pinpoint a specific horsepower number to each piston or a certain psi. It all depends on what turbo you use, how well you tune the car, and the current condition of the motor. Its silly to argue about minor details with stuff like this.

Neil_Y, no you dont need to upgrade the pistons or anything internal on the engine, however its a good idea to see what kind of shape your motor is in. If you have a lot of miles on it, or if its currently burning oil or has any other issues, it might be a good idea to rebuild it or swap for another engine thats in better shape.

i am using 180sx turbo with 5sfe engine. the engine got about 160000km.
i don't know does it have oil burning. just oil leaking litt bit.

This post has been edited by Neil_Y: Apr 28, 2009 - 7:07 PM

[supershannon77]

Your car is already turboed?
Is it running ok?
What turbo are you running?
What are the specs to your set up?
how long have you been running the turbo?

This post has been edited by supershannon77: Apr 28, 2009 - 7:09 PM

[Neil_Y]

Your car is already turboed?
Is it running ok?
What turbo are you running?
What are the specs to your set up?
how long have you been running the turbo?

it's not my job. the last owner did it.

This post has been edited by Neil_Y: Apr 28, 2009 - 7:12 PM

[_Jim_]

I think Smaay just rounded down to provide some basic ball park number. You cant pinpoint a specific horsepower number to each piston or a certain psi. It all depends on what turbo you use, how well you tune the car, and the current condition of the motor. Its silly to argue about minor details with stuff like this.

Neil_Y, no you dont need to upgrade the pistons or anything internal on the engine, however its a good idea to see what kind of shape your motor is in. If you have a lot of miles on it, or if its currently burning oil or has any other issues, it might be a good idea to rebuild it or swap for another engine thats in better shape.

Yes agreed that you cannot pinpoint a specific HP number, I haven't done this. I gave a more REALISTIC ball park number. Pressure is pressure, so 15 pounds of pressure is the same for ALL turbos.....so 15 pounds of pressure from turbo A is just as safe as 15pounds of pressure from turbo B, EVEN if turbo B flows twice the amount of air as turbo A. The pressure is still equal. Which is why I say 15psi will not hurt a stock 5sfe motor, its been proven SEVERAL times.

Everyone knows that bigger turbos flow more air at the same psi then smaller turbos, this is why I said the 5sfe is good for SUB 300whp (350hp) and SAFE at 15psi. The original poster can use any turbo he chooses and be safe using these values as a guide as long as long as neither value is exceeded. If he buys a MASSIVVEEEEEE turbo and runs 300whp at 11psi he is fine.....If the original poster runs a smaller turbo and makes 240whp at 15psi, he is fine. Both instances have different HP to PSI ratio, but BOTH are equally safe because both setups are within the "safe" limits of SUB 300whp and up to 15psi.

Yes, all motors are different. and everyone wanting to turbo charger there motor should do there own due diligence. All motors should have a leak down, and compression check done before committing to a turbo setup. These test will allow a look at what condition the motor is in, and should be done first. If all tests come back with good results, then these safe values are just that....safe. As for tuning, that's a given.....if you don't know what you are doing you can blow a motor at ANY HP level or ANY PSI level.

[alltracman78]

Well, 15 lbs on one turbo isn't the same as 15 lbs on another turbo.

The more efficient the turbo is at that pressure, the less heat it will create while compressing the air, therefore the safer it will be for the engine, all other things being equal.

[_Jim_]

hahahahahah, now were REALLLYYYYY getting into it.

[lagos]

Well, 15 lbs on one turbo isn't the same as 15 lbs on another turbo.

The more efficient the turbo is at that pressure, the less heat it will create while compressing the air, therefore the safer it will be for the engine, all other things being equal.

^ what he said.
That's why you cant say that the motor will be fine at some arbitrary psi number.

[alltracman78]

That's why I say just run it 'til it blows.

[_Jim_]

Yes, but the difference in heat from the most commonly used turbos for the 5sfte setup is negligible at 15psi.

[alltracman78]

I was just correcting a generalization you made.

I don't know specifics on the turbos, so I won't comment on that.

[lagos]

Yes, but the difference in heat from the most commonly used turbos for the 5sfte setup is negligible at 15psi.

Not really.
A ct26 starts to run out of steam and generate a fair bit of heat at that boost level. If we had a proper compressor map for it, we would be able to see that more clearly. Thats why you dont really see a gain in horse power when you start going about 14-15psi on a ct26, but you do see a gain in torque . This is because the turbo is maxed out.

[_Jim_]

Jeremy, You are the best

This post has been edited by _Jim_: Apr 28, 2009 - 8:21 PM

[_Jim_]

Yes, but the difference in heat from the most commonly used turbos for the 5sfte setup is negligible at 15psi.

Not really.
A ct26 starts to run out of steam and generate a fair bit of heat at that boost level. If we had a proper compressor map for it, we would be able to see that more clearly. Thats why you dont really see a gain in horse power when you start going about 14-15psi on a ct26, but you do see a gain in torque . This is because the turbo is maxed out.

Yes, a ct26 hairdryier at 15psi on a 5s (any motor for that matter) will in fact start to run out of breath at 15psi...BUT IS STILL Very safe to run at these boost levels.

As for the topic of heat.....this has been HEAVILY combated with the use of water injection. I recommend a Water Injection kit to ANYONE thinking about running a turbo on there setup. Most of the people running the 5sfte setup have there water injection to come on at 6-10psi.