apache

I know whats function is, but why did Cummins change from the first gens?
I feel like a moron tryin to figure out my 95 compared to my 93. its all different and so confusing

Lil Dog

In quick and dirty terms.. Quicker response without the smoke..

If you can build boost earlier for the fuel you want to give it, its alot cleaner. Its basically the same reason they went from the 21 cm to the 18.5cm housings from 92 to 93. Low power and sluggish response was the main cause for the change.

Whats the part giving you greif? (coming from a former 1st genner too)

J-eh

infidel

The wastegate bypasses exhaust around the turbo once the set boost pressure is reached to prevent excessive boost. The reason why the turbo can over boost is because it's matched to the engine to build boost faster (spool up) at lower rpms to avoid smoke and produce more low end power. Generally the larger the turbo the slower the spool up, a wastegate isn't needed with larger turbos since they usually won't produce excessive boost.

Rganser

next question, does a stock 94 need a wastegate? Is the stock turbo capable of damage? Reason i ask is because i am going to buy a truck tomorrow, but the wastegate is disconnected, do i need to be worried aboupt anything? It also has 4" exhaust on it right now, otherwise stock.
Ryan

cumminsdriver635

If its stock, then theres nothing to worry about as far as overspooling the turbo. Thats why the Fuel plates come with boost elbows; so that you can build more boost to burn the fuel cleaner, and make more power.

Eric

Lil Dog

The pressure "red line" for the HX-35 / WH1C is around 35 Psi. So unless you are going to do some pretty major mods right away, the plugged wastegate is not a problem. The stock boost on that engine is around 16-18 Psi.

Rganser

So the factory turbo with the wastegate is 18 psi? but unhooked it is running 35 lbs?
Ryan

infidel

You will only achive 35 psi if you also add more fuel by changing or adjusting the plate.
'94&'95 wastegates are set at 15-18, '96-'98 at 21-23.

Lil Dog

With the stock fueling of the 94 CTD, even with the wastegate unhooked you would only get around 19 psi at full load at full RPM.

The rule of thumb is around 10Hp per Psi.. If you have 35 psi boost you should be around 350Hp, give or take some other variables.

What I was trying to say is that even if you put a fuel plate into that engine for increased power, you wouldn't have to worry about the wastegate operation till you reached the 300 hp mark..

Sorry for the confusion.

apache

Whats the Elbow? I keep seeing questions about it. Lil Dog, Im not having any problems, just wondered. The 2nd gen is a bit different and Im tryin to figure it all out. Pump, turbo sys, starin under the hood at my 93 and 95 sure is a difference. Wish the 95 was as roomy and easy to get at everything.

infidel

The elbow is nothing more than an adjustable restriction that slows wastegate movement.
Picture here> http://dodgeram.org/tech/dsl/more_power/afc_top16.jpg

Dufrain

How accurate is this or how does it work

The rule of thumb is around 10Hp per Psi.. If you have 35 psi boost you should be around 350Hp, give or take some other variables.

I can hit 35psi easy enough with my setup but I dont think im at 350hp.

Just wondering

cumminsdriver635

Yeah. 35psi here. Dyno 246hp . i dont really think that boost can tell you anything about hp in my opinion.

Eric

Rganser

Ok, how much does the stock turbo put out with the wastegate unhooked, and the pump turned up, bottom line, just curious if the truck i a looking at will be ok or not,
Ryan

Dufrain

Mines stock with a 10 and blocked wastegate it will hit 35 easy enough and I just have a 160 pump.