A-Poc

We have a 92 Dodge Diesel 3/4 ton and I was wundering if it's possible to turn up the turbo to get more horse power. If so do you know a rough estimation of how much it'd cost and how high you could turn it up to without doing any actual damage.

frostie

I have never heard of turning up a turbo. I turbo only does what it does because of the fuel and air you put to it. If you want to increase boost you can do that by puting more fuel to it. The stock turbo can only take so much before you start to overspeed it. A stock turbo can get around 30 PSI boost before it becomes inefficient. You can increase boost and power by installing a 16 CM exhaust housing on a stock turbo. you can also turn up the fuel on your injection pump to gain power and boost. That is just a start. From there your options are unlimited.
Enjoy.

A-Poc

On the issue of performance, what other little items can you add to the turbos to give you that little extra boost? Basically I started this topic to find ways to modify my turbo so I can get everything out of it. Like I said before list as many items as you can. Lend me some tips along the way

jiMMyCTD

as stated not much to do to a turbo other then upgrade it to a differ unit. you can get exhaust to get teh air out, and striaght pipe the intake to force more air in.

jiMMy

Bushy

The turbo itself, as noted, is something that you either rebuild with a stock cartridge/kit or you have it "hybridized".
This process involves machining some internal surfaces to different tolerances, changing/upgrading shaft bearings, installing different compressor wheel(s) from other applications/turbos and, rebalancing.
No matter which way you go, the next item is the "hot end" or exhaust housing size. You can use an 18.5cm, a 16cm (both require NO alterations to exhaust downpipe) ... you can use a non-wastegated 14cm housing, a 'gated 14cm, and a 12cm 'gated housing. In the case of the two smaller housings, you'll need to either "tease" your downpipe back toward the firewall about 1 1/4" OR trim the clamp flange off, shorten the pipe and then weld the flange back on.

If you use a "stock" rebuild kit/cartridge you are basically getting a stock "standard performance" turbo. As you go down in exhaust housing size eg; 18 - 16cm you will gain about 2-3 psi boost. This 'gain' is fairly constant as you keep going down in size.
The smaller the exhaust housing the more exhaust housing entry becomes a choke point... it creates high drive pressure and higher than usual EGT's.

If you choose the hybrid route, you end up with a turbo that will respond quicker, provide cooler boost and, will have an extended efficiency range.
For example the efficiency map of a stock turbo on our trucks is roughly 26'ish psi.
Beyond that, the efficiency starts to drop off and the extra boost begins to work against you rather than for you.
The hybrid delays or pushes that threshold further up. A good quality hybrid HX35 will have an extended 'map' that will take you into the mid - upper 30's psi.

Remember, you only need enough boost to burn the fuel you're supplying to the engine and that's all.
As you increase fueling to the engine, the extra fuel creates extra exhaust/heat, which in turn drives the turbo charger faster and harder.

Does that help???

pastor bob.... from the good book...

spunbearing

Apoc, I'm not sure that you understand what they are telling you or even how a turbo works.a turbo has two wheels one wheel is in the exhaust port and the hot exhaust gases spin the wheel.. there is a second wheel attached that spins and forces intake air into the engine. There are no setting on a turbo to " turn it up". A smaller exhaust housing makes a turbo spin up quicker which would give you more boost at low rpms. Other than that the only way you can get more boost from a stock turbo is to add more fuel which produces more hot exhaust gases and will spin the turbo quicker. Aa an example when I had my injector pump rebuilt and turned up I gained 5 psi. of boost. I'm new to all of this too but this is the way I understand things... hope it helps.

spunbearing

Hey bushy! I have a question for you. :0) I've been considering a 16cm2 housing for mine but was also considering an hx-35 to replaced the H1c. Is this a bolt up application or will I need to modify my new exhaust system? I think I'm doing things backwards. LOL

wannadiesel

HX-35 or WH1C is a bolt-on IF you use the 16 cm housing. If you run the 12 cm housing that comes with the turbo you will need to move the exhaust back 1.5 inches. You can sometimes "cheat" the downpipe back far enough without hitting the heater box insulation, or you can cut the flange off the downpipe, remove the "extra" length, then weld the flange back on. I did my exhaust and 12 cm turbo housing the same day, unlike some people.