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4bt turbo fitment

user_error

New Member
Joined
Aug 19, 2014
Messages
12
Loc.
Seattle area
I am in the process of restoring a '70 and going with a 4bt setup.

I bought a complete 78 f150 with a 4bt and zf5 transmission.

The 4bt has a compound turbo setup in it. I am not sure if i can, or want, the compound setup in the bronco

I do not want to cut out the inner fenders to fit a absurd turbo setup.

Does anyone know first hand if a compound setup will fit without body modifications?

If not, what single turbo should I be looking for?

The 4bt has extensive mods. 13mm machines P-pump with injectors, cam, fuel pin, governor spring, race cam, ect. All Cummins Diesels in Utah built the engine capable of 500hp, but I do not need to push that limit. Somewhere between 300 and 400 would be ok with me.


Sidenote, is it not possible to attach images that aren't hosted on a website? I'm having a hard time uploading a picture.
 

Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
34,834
There was a twin turbo 4BT Bronco at the AZ stampede a few years back. 2016(?)
It was a work in progress but all the big parts were in place.
 

Pa PITT

Contributor
Bronco Guru
Joined
Jul 15, 2005
Messages
11,252
Loc.
Stephenville TEXAS
.. I HAVE THE 4bt in my Bronco .. BUT I don't even know what a compound setup is.. I'm expecting 2 turbos.
... My Bronco just has the stock turbo on it. Mine is about stock .. I only wanted a machine that runs much cooler & Get 5 times better mileage. I probably don't get mine over 20mph once a month.
 

MonsterBIlly

Sr. Member
Joined
Dec 17, 2015
Messages
456
I would keep the sequential turbo if you can. It will limit if not remove the turbo lag. It sh ok old make it better to drive in most scenarios
 

JB Fab

Sponsor/Vendor
Bronco Guru
Joined
Mar 21, 2004
Messages
1,240
We have two 4BTAA Broncos, One has been modified for significantly increased for performance (not as much as yours). The one thing I can tell you is if you change your turbo set-up and it changes the amount of available boost the engine is tuned to (especially at that output level), you will have issues with over-fueling and you EGTs will be through the roof (to the point of meting pistons if your not very careful) At 500hp don't expect stellar fuel economy, and expect service interval for certain hard parts to be greatly reduced.
 
OP
OP
U

user_error

New Member
Joined
Aug 19, 2014
Messages
12
Loc.
Seattle area
Do any of you guys have issues with fitment near the passenger side inner fender?

I've been doing some reading and it looks like there are a few different styles of exhaust manifolds that orient the turbo in different positions. Do you guys have and pictures of your setups specifically near the passenger side fenders?
 

Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
34,834
The few I have seen had fitment issues everywhere. Notching of the frame is common. Makes sheetmetal work easy at that point. I have only seen one compound turbo build, and it was still a work in progress.
 
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