I added a turbo to a Ford 7.3 IDI diesel, it changed the world, and now I think everything should have one, or two.

I have two fresh engines, both fords, 351W/427 and 460/604. I did not build them and the builders were not planning for boost. They are 10:1 aluminum heads. They are getting blow thru EFI and two small turbos limited to no more than 10#.

Am I going to have problems?

Is water/alcohol possibly a good idea, and can it work with blow thru.

 

You can run E85 . You'd have to up your fuel system to run e 85.

 

Pump with meth injection will work as well. The cam selection plays a role too.

 

[QUOTE="Mnlx, post: The cam selection plays a role too.[/QUOTE]

Is this to bleed off some cylinder pressure?

 

Yes, something with a bit more duration, and overlap.

 

Either engine should be fine with boost and 10:1. Just pay attention to the tune and don't get greedy with the timing. Like stated, you can effectively reduce the dynamic compression ratio with camshaft changes if needed.

 

At a constant 70 MPH on a flat road, what would I expect a vac/boost gauge to show?

 

Depends on many things... But mainly load, rpm, and turbo choice. It's common to cruise with zero boost.

 

You should be well into vacuum, maybe 10 in/hg. Climbing hills with a heavy vehicle is when it will start to get into boost.

Do the engine have forged internals? I would verify that the engines are stout before adding turbos, though limiting the boost to 10 psi will help. You are going to need the largest A/R exhaust housing they make for the 604 ci engine!

Al

 

My 9K#, 84/89/93 E350, turbo at 70 MPR is barely into boost.

 

I assume you're talking diesels here? Diesels are much different given their usable rpm. My 04 Cummins cruises at 75 with about 10 psi at 1850 rpm.

 

There are a few pics of the 604 here.
https://goo.gl/photos/aF9XY5czAW6ZAuqG8
I don't recall the crank, but the pistons are Diamond, the rods are H beam, and the cam bearings are roller. The 427 is a bit less.

I am going to nibble at turbo selection. I am going to start with what I have in stock, which is two pair of T3/T4s. One pair has built in waste gates, which based on a Hot Rod article may be too small. Those will go on the 427. The 604 will get added waste gates.

Both have two inch ID exhaust outlets and three inch V band. I am running 2.5 inch exhaust.

At SEMA last year I talked to an engineering manager at a company that builds WGs and BOVs. We were talking about BOV sizing. He said, which he said is as proof he is not a salesman, an auto transmission car does not need a BOV.

 

If the 427 has anything other than stock heads it'll need much more turbo than the t3/t4's..... You technically don't need a bov, but it can be very tough on turbos. Many also say anything less than 10 psi doesn't require a bov.

 

Would that mean replacing the entire assembly or maybe just half of it?

Both have Trick Flow heads.

 

Yes, it is a 93 7.3L IDI turbo diesel. The turbo is a rebuilt 2000 7.3L PSD unit and is mounted on the frame at about the rear of the trans. 10# is about the max I have seen. That is third gear, foot on the floor, up hill.

 

Depends on the compressor, but typically the whole unit. Without knowing more about the engine, a 427 with a decent head will require a pair of good sized turbos to be happy.

 

With 213 ci feeding each turbo, a full T4 with external WG sounds better suited than a T3/T4 with internal WG. Going to need a large exhaust housing.

Too small of a wastegate can give you boost creep - which is boost rising with RPM, especially in cold weather. Very undesirable.

Al

 

When I added a turbo to my 7.3 IDI diesel the advice was to add exhaust temp gauges. So I did, right after each manifold.

Does the same advice apply to gas engines?

 

A wide band is much more useful than egt in a gas application. Egt's are good for cyl to cyl tuning, but "safe" temps can vary greatly from setup to setup.

 

Your 04 Dodge also has a vastly different turbocharger than what his IDIs would have. Respectively.