Max psi of my turbo

[GARRICK.CLARK]

Guys.
How do I find out what the SAFE max psi my turbo can go too.
I have looked on line for info on it but cant find any.
My turbo is GT2256S. Its a DIESEL PERKINS one.
I boost my motor to 1 bar. I don't consider 1 bar to be a lot and think most modern turbo's should be able too go beyond this and live .
thanks.

[saltgrinder]

Hey man , you really need to have the compressor map or have it mapped to know
My standard CT26 on my Toyota landcruiser will push upto 20 psi BUT after 13.5 psi it heats the air terribly and surges like a bitch . Last thing you want to do is lunch a compressor wheel , I've done it ,more than once , makes a huge mess

Richard

[Buggsy]

Closest I could find. https://www.turbobygarrett.com/turbobyg ... ers/gt2252

[Clonebug]

You should be good to 21 lbs and maybe more.

It's going to be all about how many CFM or lbs./min. your engine requires and how much your turbo will flow at max rpm.

Here is a good calculator to figure out what your requirements are and then see if your turbo can match it.

http://www.rbracing-rsr.com/calcboost.html

For example you can punch in my numbers on my engine.

Peak HP.........250
AFR ratio.......12.0
BSFC............0.55
Charge Temp..107
Vol Eff..........0.95
Peak RPM......5700
Displace in CI..102

So the answer is

Boost required......21.41 Lbs. boost
Lbs. air per min....27.5 lbs per min.....and 340 CFM.

My turbo is capable of 394 CFM and will support 270 hp at minimum...possibly more.

If you place your numbers in the spaces you will know how much air you require and then can find out if your turbo can flow that much.

I have found it to be pretty accurate. If I check my injector flow it matches pretty close to what my targeted HP is.

For ex.

I have 45# injectors that support 360 hp at 100% Duty Cycle.
I am at 70-73% Duty cycle right now when I run 22 lbs boost.
That puts me at a fuel burn of 360 X .70= 252 hp.

So according to the math calculations I should be right at my targeted hp.

Try your numbers and see what you want to get.

[GARRICK.CLARK]

Interesting stuff.
I've looked at the rbracing site and put in the numbers.
250 hp
11.1 AFR
0.55 B.S.F.C
130 AIR TEMP
.95 V.E
5700 REVS
116.61 C,U
15.43 BOOST
25.21 POUNDS AIR PER MINUTE
312.38 CFM

For 300 hp I need 21.46 psi boost

Cool web site.

The chart also proves that the lower the air temp the less psi you need for a given HP out put.
I lowered the temp number from 130 going down to 100 and the psi dropped from 21 down to 19

[Clonebug]

I have read a lot of that website. Granted they are into Harleys but they seem to know their stuff.

I copied their Water Injection setup to an extent also.

There are some good calculators there too. Go to the top of the page and they have a tab that takes you to a page full of them.

Good Stuff.

Punching different air temps into that calculator is what pushed me to find any way to get an intercooler on my buggy.
Even just lowering the air temps from 140 degrees to 107 made a very noticeable difference.
I'm now working on the efficiency of my intercooler to see if I can get even cooler air.

[GARRICK.CLARK]

Nice 1 clone.
I'm having a bracket welded over the weekend so the intercooler is at an upward angle . hopefully this cooler will catch the air as it travels over the back of the bug.
There is a fan attached to it also.

What sort of air temp gauge/kit did you buy and were is the sender positioned.
Cool.

[Clonebug]

I have it all thru my MS-2. It uses a GM sensor in the intake below the TB.

[GARRICK.CLARK]

Hi Clone.
I got the intercooler fitted, Only Tested it today. Too much bad weather.
Any way, did the test , returned back to base and notice the carb and the manifold just past the butterfly are now frozen with ice and the only thing that works to get rid of it is to turn the motor off and let it thaw by itself. The cooler must be working then. I also noticed that now the cooler is fitted the fuel enrichment that works purely off boost pressure is making the motor a little leaner, This must be because the air pressure must be reducing because of the big cooler. I'll increase the tension on the w/gate actuator to get afr back to how it was before.
Regards Gee C.

[66brm]

The air out of the cooler is more dense now so you will need more fuel to compensate, the benefit is more power as a result

[Clonebug]

Hi Clone.
I got the intercooler fitted, Only Tested it today. Too much bad weather.
Any way, did the test , returned back to base and notice the carb and the manifold just past the butterfly are now frozen with ice and the only thing that works to get rid of it is to turn the motor off and let it thaw by itself. The cooler must be working then. I also noticed that now the cooler is fitted the fuel enrichment that works purely off boost pressure is making the motor a little leaner, This must be because the air pressure must be reducing because of the big cooler. I'll increase the tension on the w/gate actuator to get afr back to how it was before.
Regards Gee C.

I can't remember what setup you are running anymore.

Are you blow through or drawthru???
Draw thru is what it sounds like if you are getting icing on the carb. You do not want to run an intercooler with a drawthrough and put fuel through the intercooler. It can very easily backfire and blow everything to kingdom come.

[GARRICK.CLARK]

Hi Clone.
Its blow through now, I wont be doing draw through again, too much hassle.
66brm, after the cooler was fitted I did have to increase the fueling as it was showing lean on the AFR gauge.