johnsjas

I was looking into nitrous, but I am worried about my head gasket. Currently I am putting out 60psi with my turbo. I need to know what the stock gasket will take and what needs to be done to equip nitrous.

Thanks

vssman

60psi with a stock gasket?? I'm surprised it's still holding. Stock gaskets are typically good to the upper 40's/ very low 50's. After that, it's a matter of time. What turbo are you running to 60psi?

johnsjas

The turbo is a super b and I have a overboost elbow on the line to the waste gate.

pmtg

why nitrous? because you want to or because you are running too hot with current setup?

if you're are running too hot:
im not too familiar with the super b but my guess is at 60psi you are superheating the air. a larger wastegate (external) would help vent off more exhaust and most likely increase your HPs, eliminating the need for nitrous. or get another turbo...

just my guess

edit: either way, get ready to pay when playing with nitrous

Diesel-Dan

I would say that 60PSI is a little high.....you might be overboosting a bit....i want to say that 45ish is about the upper limit of good boost...after that....hot air...i could be wrong...but 60 just seems high....

ALSO....just go a head if and pull the head and get studs and a Multi-layer Headgasket or firerings if you are looking towards nitrous.....you will pop it.....no if ands or buts......i dont see how its holding 60!!

Myth: More Boost = More Power (that is true to a point, think of a bell curve)

There is a point in a turbo's map that after that, its all hot air...and the boost numbers you are getting are from heat expansion rather than air being forced in by the turbo....its a balancing act...and you have to try to stay within the turbos efficiency range to get the most out of your turbo/motor....

RowJ

Agreed!
Anything over 45 psi on a Super B is expansion pressure....not compression pressure....probably not making any more HP than would get at 45 psi. Dyno testing would comfirm this fact.

Nitrous will only create more problems! Much higher cylinder pressure and TIP (turbine Inlet Pressures) or Drive Pressure.
Anyone on a stock HG at 60 psi boost is living VERY close to the edge!

RJ

johnsjas

I havent had my truck on a dyno but hope to summer of 06. I can always adjust my wastegate to cut down the pressure if the dyno shows more power at lower psi, right? As far as nitrous, I just want more power and 12's in the 1/4 mile.

pwrtripls1

Have you thought about water/meth injection? It would cool and condence your intake charge more and slow the fuel burning for a more complete burn, thus making considerable more power without sending cylinder pressure through the roof.

In answer to your question though, nitrous would make your boost go up a little, and if your blowing a black cloud like a train it will help get more oxegen in there to clear it up and make more power. BUT, your cylinder pressures WILL go through the roof and you WILL pop the head gasket. You could try the somewhat cheap and easy fix of getting a really good head gasket and ARP head studs, then over torque then about 15lbs. That should hold up to what you want to throw at it, but even thats on the edge.

I do wish you luck with 12's though, it sounds like you have one killer setup going.

RowJ

Adjust wastegate down? Usually not doable unless you have blocked it off. If so could go back to full wastegate with a MBC (manual boost controller) and control increases that way.

RJ

HOHN

Agreed. Nitrous without some serious wastegating is a BAD idea.

First, lower your WG setting to 45 or so. Most S300 based compressors (B1, Super B, PS62, etc) are going to top out around there for efficiency.

THEN, if you still have EGT/smoke issues at 45psi, add your nitrous. But do NOT allow the nitrous to raise the boost. That's why you need a large wastegate. Some turbos have really good internal gates (SPS66 comes to mind), other will need a large external to do the job.


The only was faster than Nitrous for taking out a HG is nitrous AND propane

Jetpilot

You need to wastegate your charger down between 40-45 psi, even if you aren't running nitrous. You will need to O-ring your head to run giggle gas.... Trust me you will blow your headgasket running nitrous and no rings. As Hohn mentioned a key element is the ability to wastegate off excessive pressure, nitrous raises cylinder pressers dramatically and you need to be able to get it out of the engine. Running a progressive controller helps as well. Be sure and get a goob heater to ensure proper bottle pressure each and everytime. Also some time spent on a dyno tuning it is essential, otherwise you have no idea what its going to do running different pills.

Doug

northslope

https://www.dieseltruckresource.com/...ight=arp+studs

johnsjas

I placed a valve inline with the line that runs to the waste gate to adjust the presure. I will adjust it down to 45 psi but wont know anything for sure until the roads get nice and clear thanks to michigan weather.

greenworks

how in the world are you even getting 60 psi out of a super b? I consider my truck to have a fair bit of fueling and I can get high 30's never 40 psi even with the wastegate physically blocked, I was even sent another turbo being they thought my first unit was broke, What are you running for injectors and fuel enhancements, and roughly what elevation are you at??

johnsjas

I have custom injectors that give me an extra 220 hp. A bully dog stage 4 plate slide forward, delivery valves (191), 4k gsk, and as far as elevation I have no idea, I live in western michigan.