How much boost is too much with an otherwise stock 1993 6.5?
 

I have a 1993 K3500 that gets used mainly to pull my 30 ft 5th wheel camper with my 16 ft fishing boat towed behind the camper. Up until this week it was completely stock and pulled OK as long as the ground was flat. Thanks to everyone on this site, I've turned up the injector pump 1/4 turn and added an extra spring to the stock mechanical waste gate actuator. My boost is now peaking at just under 15 lbs and seems to maintain around 12, before adding the extra spring, boost would peak around 9 lbs and maintain around 5 lbs. My question is, how high can I safely run the boost without doing more mods to the engine, like head gaskets, etc?

Thanks for your help.
Kevin

Thats probably all your turbo will maintain and thats about as high as I would run any way.

Thanks for the info, just wanted to make sure that wasn't too much, I won't try to go any higher.

There is a place that makes a turbo just for the 6.5. The problem the stock turbo has is that at higher speeds it cant supply the volume of air needed. I don't know how to post a link because I suck at this stuff but its called a A-Team turbo and there supposed to make a big difference in how these trucks run. I never have ran one but I have heard good things about them and am thinking of running on. Plus they can be run with a stock 6.5.

here you go
Walking J Designs - 6.5L Diesel Turbo Charger (A-Team)

heres some info on it

Replacement turbo - The Truck Stop

What spring did you use to accomplish the 12 15 and where did you get it?

Your just flirting with disaster running 15lbs with the junk gm turbo, they are much to small for a 6.5 They cause much to high back pressure on the motor which stresses it. most likely the reason people blow up a 6.5. Max boost i would run on that turbo is maybe 12psi max. If your looking for more reliable power you need to upgrade to a bigger better turbo for example a Holset HX series from a cummins motor. The same or more power can be had at same and lower boost levels. your fuel economy will also go up. Guys are running 20+psi on their 6.5s without any internal mods, all has to do with the turbo being ran. Not saying you need that much boost just saying its possible.

That makes sence cuz the stock spools up a lot paster but what if im running new oil and a inter cooler wouldnt that help keep my turbo safer, im only running 9 OSI max right now id like to go to atleast 12 max so I need a spring tht would accomplish that

If 9psi is all your running then an intercooler is not needed. regardless if your running an intercooler or not, the gm turbo is still a huge restriction. I would put the money towards a better turbo

theres no such thing as to much boost :c: