How much PSI Safe ?

[lvmustanggt]

http://www.youtube.com/user/lovetorace

I got on 3 performance single turbo kit running with mpT70 turbo. First dyno it made only 5.5 psi so I add one spring then went for 2nd dyno and made 8.22 psi. But both dyno time I had exhaust leaks and now that I fix my leaks it look like it's pulling 9 psi or little more.

Question is supercharger guys are pushing 10 psi on stock block but my turbo at only 8.22 psi made 424rwhp and 454 torque. With 9 psi I might be close to 440rwhp and I am worried but my tuner says it's ok to run 9 psi without problem and my tune is very safe tune.

Today i change wastegate springs that suppose to make 8 psi but my gauge shows me almost 11 psi Got off the boost and tried one more time but still look like 10-11 psi.

I will be putting the spring back so I don't make over 9psi.

My car is 2002 mustang gt

 

[oxfordgt]

You can answer a question like that. Boost is only a measurement of restriction. For example my engine is a very efficient high flowing engine and I see 18psi. If you were to take my supercharger with all the piping, intercooler and same pulleys and stick them on a stock engine you will see anywere from 25 to 30lbs of boost. Your question should be how much power can I safely make with a turbo and at 424hp on a turbo 4.6l you are a ticking time bomb. Turbos hit much harder then a supercharger and are much more stressful on the stock internals.

 

[lvmustanggt]

up to 430rwhp with good tune is safe I heard and my tuner tell me but damn my car just keep making more power

I am going to put the softest springs I have and will do manuel boost controller so I can do exatly 8 psi or little more.

 

[LaserSVT]

And you can prolly run 500+ on the dyno without blowing up but the street is a different animal. Go WOT in second then third then in fourth.... BOOM! And now the block has a window in it
The rods/wristpins/pistons just cant take it. When they were building the Terminators they had the same rods at first untill they blew 20 of them up on the dyno at only 400 hp. The Ford rods only cost $1.60 each, the Termi rods cost them $56 each now. Just enjoy the power you have right now and when the budget allows get yourself a built bottom end and crank her up!

 

[lvmustanggt]

Home made oil separator video .
Husky mini oil separator from home depot $12
2 1/4 NPT 3/8 barb 2.50 each $ 5.00
3/8 fuel line hose 4' $ 5.99
Home made oil separator for $ 23.99 Yayyyyyyyyy

http://www.youtube.com/watch?v=jplKyghh7E0&feature=channel_page

http://www.youtube.com/user/lovetorace

 

[LaserSVT]

Home made oil separator video .
Husky mini oil separator from home depot $12
2 1/4 NPT 3/8 barb 2.50 each $ 5.00
3/8 fuel line hose 4' $ 5.99
Home made oil separator for $ 23.99 Yayyyyyyyyy

YouTube - Home made Oil Separator for Mustang Gt

YouTube - lovetorace's Channel

Damnit! I spent $65 on mine!

 

[deftsound]

im pushing 10 psi with no problems

 

[Flghtmstr1]

I am also running 10 psi (actually somewhere between 10 and 10.5) with no problems yet. :knocks on wood:

 

[lvmustanggt]

im pushing 10 psi with no problems

Problem is I am making more then you at 8.22 psi, at 9 psi I may be at 440rwhp 480 toqeue that's why I am worried about.

 

[lvmustanggt]

I am also running 10 psi (actually somewhere between 10 and 10.5) with no problems yet. :knocks on wood:

I am going to cut wastegate spring a little to lower boost.

 

[the98stang]

Turbos hit much harder then a supercharger and are much more stressful on the stock internals.

That is wrong. Superchargers are more stressful than turbos if you are comparing twin screw to a turbo. Twin screw create the boost almost instantly causing instant pressure in the combustion chamber. Where as with a turbo the boost will take a little longer to hit. Blowers also put more stress on the engine since they are belt driven (versus exhaust driven for the turbo).

That being said, you need to look at the HP numbers as a "safety" guideline. Most people will tell you 450whp is the max these stock engines can handle. Some will even say 400. It just depends on how you want to roll the dice. One member on here (hotmustang) pulled over 500whp from his stock 4.6L with twin turbos and the engine never popped. If your AFR is conservative (like 11.0) and your around 400-450whp I think you would be fine. If you want to throw the dice a little bit you can add some more timing while keeping the same boost levels to gain some extra power without increasing the pressure in the cylinders.

I would also highly recommend a turbo timer and an electronic boost controller (manual waste gates are dangerous because they can change the psi without you knowing). I hope this helps your decision!

-Tanner

 

[lvmustanggt]

I have 2 springs , one big and one small. I cut some coil spring out of small spring and now it look like 8.5 psi perfect.

 

[blksq10psi]

your stock internals will safely hold 450 hp to the tires 480 and you just pulled the pin on your gernade i wouldnt go more that that with stock guts

 

[lvmustanggt]

That is wrong. Superchargers are more stressful than turbos if you are comparing twin screw to a turbo. Twin screw create the boost almost instantly causing instant pressure in the combustion chamber. Where as with a turbo the boost will take a little longer to hit. Blowers also put more stress on the engine since they are belt driven (versus exhaust driven for the turbo).

That being said, you need to look at the HP numbers as a "safety" guideline. Most people will tell you 450whp is the max these stock engines can handle. Some will even say 400. It just depends on how you want to roll the dice. One member on here (hotmustang) pulled over 500whp from his stock 4.6L with twin turbos and the engine never popped. If your AFR is conservative (like 11.0) and your around 400-450whp I think you would be fine. If you want to throw the dice a little bit you can add some more timing while keeping the same boost levels to gain some extra power without increasing the pressure in the cylinders.

I would also highly recommend a turbo timer and an electronic boost controller (manual waste gates are dangerous because they can change the psi without you knowing). I hope this helps your decision!

-Tanner

Asap funds available I will get Aem boostgauge/controller .

 

[lvmustanggt]

your stock internals will safely hold 450 hp to the tires 480 and you just pulled the pin on your gernade i wouldnt go more that that with stock guts

I may be close to 430-435rwhp now and got good tune so I feel good. I look at your sig and you pushing 10 psi and getting 385rwhp That's why I went turbo. Turbo FTMFW

 

[LaserSVT]

+1 on the boost controller. Blitz makes a very kick ass one that is a very percise controller. http://cgi.ebay.com/ebaymotors/BLIT...TruckQ5fPartsQ5fAccessoriesQQsalenotsupported

Its a bit expensive but the stability of your boost will be unmatched. Just put the 5psi spring in and if the controller ever fails the turbo will default to 5psi
You can even program it so when you launch it can give different boost levels in 100 rpm increments to help get off the line and then mabey spike it for a second or two when in third.

 

[lvmustanggt]

+1 on the boost controller. Blitz makes a very kick ass one that is a very percise controller. http://cgi.ebay.com/ebaymotors/BLIT...TruckQ5fPartsQ5fAccessoriesQQsalenotsupported

Its a bit expensive but the stability of your boost will be unmatched. Just put the 5psi spring in and if the controller ever fails the turbo will default to 5psi
You can even program it so when you launch it can give different boost levels in 100 rpm increments to help get off the line and then mabey spike it for a second or two when in third.

Nice unit but I could never be able to buy 700 boost controller. I will be happy with aem boost gauge/controller and wot box.