Banks sidewinder boost pressures?????

[frdtrckmnrich]

I have an 85 6.9 with a banks sidewinder turbo and the injection pump turned up 3/4 turn. I was wondering what kind of boost pressures everyone else is getting. The last 2 days while towing a mild load i watched my gauge hit 14lbs. I was under the impression that these turbos would peak out at 12lbs. So what do you think?

 

[argve]

do you have the wastegated version?

 

[Diesel JD]

Travis' question is the operative one. A wastegated turbo will not let you overboost the motor as long as the wastegate is functional and properly adjusted. Normally I think the Sidewinder will stop you somewhere in the 12-15 psi range depending on the wastegate adjustment. If its non wastegated it'll keep boosting till the engine blows provided you have enough fuel to make that boost. That's why non gated turbos must be correctly sized to the motor or else you must watch your boost and pyro very carefully.

 

[frdtrckmnrich]

I have the non wastegated system.
So how much is too much? I recently put head studs and new gaskets in.

 

[argve]

since it's a non wg verison then it won't build much higher because the turbo is sized correctly so you shouldn't be able to generate enough fuel and heat / volume to overboost the engine. the reason I was asking was to see if maybe the wg had been adjusted or bypassed because with the wg versions they will limit the boost to 12psi because after that you start to super heat the air and there isn't much performance left in them because of that fact - but with a non wg version it's a little larger turbo so it will spool a little slower but will allow more volume at higher rpms.

what's all this mean.... your doing fine and have no worries mate. Enjoy....

 

[Diesel JD]

I think that your motor can easily take the 14psi with the upgraded studs and gaskets. Just make sure to keep the egts under control.

 

[Mr_Roboto]

Personally I think I would turn down the pump some so you don't end up with even higher boost when you have a heavy load on.

 

[frdtrckmnrich]

The egt's have stayed under 1050. I am thinking about propane in the future. Think i will be safe??????

 

[82F100SWB]

With a heavy load on behind my truck(20,000 GCWR+) I start to get lots of turbo flutter/surge around the 14-15 psi range, the boost guage starts to float around(it does this empty also,) and it never goes past, even when I manage to bring those boost levels up below 3000 rpm, I have seen 18psi before, but, that was with -40 ambient temperatures. I'm going to expirement here shortly and turn the pump up some more, I have a feeling that with how the compressor side of the turbo is sized, 15 is about all it's good for, more is too far beyond the CFM it's efficent at moving(off the map if you remember the twin turbo thread where I explained sizing.)

I have a feeling that adding more fuel is just going to make more smoke, and not more boost. I may be wrong, but, I'm pretty certain that I'm at the limit for this turbo as it sits.

 

[Diesel JD]

I wonder what the safe limit for a turbo IDI with head studs and upgraded gaskets is. It should be somewhere more than the 12-15 that we normally say. I have heard that without an intercooler, anything more than 13psi is probably just wasted as heat, from some folks who should know, but how they arrived at this figure I do not know.

 

[Agnem]

I think once your in the mid teens, your knocking on heavens door so to speak.

 

[haywire]

I think once your in the mid teens, your knocking on heavens door so to speak.

with or without head studs?

 

[jimraelee]

my buddies 06 f250 6.0L( i know apples and oragnes) hits 35 often... maybe thats why the 6.0s will pull the head studs, and ARP head studs are such a pop upgrade on the newer trucks... sounds like people/ford is pushing the limits of the newer engines compared to your 14psi sidewinder

 

[Diesel JD]

Its apples and oranges for sure. The 6.0L is a DI engine, this it has lower compression ratio to start with(even though the absolute compression values should be similar) the dynamic compression differs. I don't know what the CR of the 6L is, but the 7.3 IDI is 21.5:1 and the 6.9 IDI is 20.7:1. The 7.3 powerstroke is 17.5:1 if I recall. It makes a big difference.

 

[jimraelee]

Ok JD, not to hijack this thread I moved over to here, if you care to look...

http://www.oilburners.net/forums/showthread.php?p=227627#post227627