how much boost can the stock turbo handle?

[sweet66monza]

my '93 IDi 5 spd has the stock turbo on it still. i DO have a boost gauge and pyrometer hooked up, otherwise the truck is totally stock.

I have always made a max of 8 lbs of boost, no matter what. Last night I installed a boost valven on the truck. Right now im makin 12 lbs and i still have more adjustment, but im not sure what the stock turbo/wastegate/motor can handle and i dont really want to find out the hard way. what do y'all think?

TIA!

 

[Silver Burner]

On a stock truck I wouldn't go much higher than that or you'll be in danger of failing head gaskets.

 

[ocnorb]

+1

Also, because these turbos are not really efficient they tend to make alot of heat over 12lbs- the hot air charge will take away as much HP as the increased boost gives you, so its kind of a waste.

An intercooler changes that equation somewhat.

 

[hesutton]

Yup, past 12 psi, your turbo is out of it's efficiency range and can surge. You won't really gain HP as the air is being super heated by the turbo and you can kill the thrust bearings.

Heath

 

[pdxfordguy]

I have a 92 7.3 idi ... I have installed the banks sidewinder turbo kit with pyro and boost .

I am wondering if the tolerances for max boost are the same ... it appeared you guys were talking about the turbo heat affecting intake temp, not the potential of the block and internals to handles the boost produced.

banks said there is no intercooler setup for the idi ... is there another company that makes an intercooler setup?

currently, the banks turbo will put a maximun of 7psi... I tow a large trailer, I dont often "get on it", but I would like to have power when towing up hills ... kinda sad that semi trucks pass me when I am towing uphill

 

[Diesel JD]

There aren't many plug and play turbo kits for the IDI. Hypermax makes one, but it isn't cheap. You're probably better off grafting in something from a 6L or 7.3L or some universal IC that runs somewhere in the neighborhood of 1000CFM. That having been said, I'm not sure I'd simply take on faith that there in no more power to be had beyone 12-13 psi of boost. It probably isn't prudent to go much further without studs. We should really calculate each one of these turbocharger's maps; they are all slightly different. As for PDX you still need a little more boost before you want to even worry about an IC.

 

[pdxfordguy]

I was concerned about turning up the boost and doing anything to harm the motor ... like rods, rings or whatever ... I read the 93 idit have bigger wrist pins, piston rings, as well as different flow capacity fuel injectors. Additionally, the fuel injection pump output was slightly increased to compensate for the additional air charge.

Do I need a boost controller to turn up my boost? Can I safely do 10-12lbs without breaking my motor? Obviously there are no guarantees, but I have no idea ...

 

[ocnorb]

I was concerned about turning up the boost and doing anything to harm the motor ... like rods, rings or whatever ... I read the 93 idit have bigger wrist pins, piston rings, as well as different flow capacity fuel injectors. Additionally, the fuel injection pump output was slightly increased to compensate for the additional air charge.

Do I need a boost controller to turn up my boost? Can I safely do 10-12lbs without breaking my motor? Obviously there are no guarantees, but I have no idea ...

Turning up your fuel=more boost.

You really need a pyro to determine your limits. Mine is turned way up, but I try to keep the EGTs under 1200.

 

[wmoguy]

I was concerned about turning up the boost and doing anything to harm the motor ... like rods, rings or whatever ... I read the 93 idit have bigger wrist pins, piston rings, as well as different flow capacity fuel injectors. Additionally, the fuel injection pump output was slightly increased to compensate for the additional air charge.

Do I need a boost controller to turn up my boost? Can I safely do 10-12lbs without breaking my motor? Obviously there are no guarantees, but I have no idea ...

you'll be fine @ 10-12psi provided there isn't already internal damage to the engine. These engines are actually very stout, and if we coudl figure out a way to hold the heads down (or you could decrease compression) they'd have no issue holding double the boost (or more) your trying to throw at it.

You certainly could use a boost controller to lift your boost levels, or just block the wastegate and use your right foot and gearing as your wastegate.

 

[icanfixall]

The wastegated turbos made by the big three are generally set to a low bost number. Thats so you don't ruin your engine and blame the turbo makers for it. Banks will turn up your fuel when they install a turbo. ATS and Hypermax tells you the same thing. Only Hypermax offers an actuall intercooler kit for our trucks. Its expensive too. I want to install one on my truck someday. I have had two of them for some time but just too lazy I guess. Your rig being stock will run much better if you get rid of the factory down pipe. The factory felt they needed to flatten it out to fit but there is better pipes out ther that fit fine. Then removing the muffler will give you more power and fuel mileage. The turbo makes the loud exhaust sound almost non egsistant. It wil be louder when the engine is pulling a load but all engines make more noise when they are working. Turning up the fuel by 1 or 2 flats of the allen wrench is whats done. After this is done you watch the full pull under load. Keep the pyro below 1100 degrees and things will be fine. Boost over 13 lbs is too hot going into the engine so why waste the effort.

 

[pdxfordguy]

the banks kit I ordered came with new 3" downpipe and I have that going into 4" straight pipe with flow through muffler dumping in front of rear tires. When they installed the turbo, they did turn up the ip, but not much ... pyro runs around 350 at idle and around 1000 with load. the turbo did make it much quieter much to my dismay lol.

 

[pdxfordguy]

im thinking about switching blocks from my 93 idit ext cab and the 92 idi cc ... is the effort worth the "return" on potential boost-ability?

 

[OLDBULL8]

You can get all the parts needed to fab up an Intercooler here, they have tons of IC's of every configeration and price.

http://www.siliconeintakes.com/

 

[hesutton]

That having been said, I'm not sure I'd simply take on faith that there in no more power to be had beyone 12-13 psi of boost.

Not on faith, on the dyno. Innercooler would help, but these kit turbo's (banks, hypermax, ats) are not performers beyond 12-13 psi. You wanna got higher, a different turbo would be the best way to do so.

Heath

 

[rjjp]

The turbo makes the loud exhaust sound almost non egsistant...

Just don't hit the governor with your exhaust tip 2 foot from a LEOs open window. They get pissed, go ahead, ask me how I know.