[Carl Donica]

bounce OK, I have been running my 4bta for about a year now. It had enough power to suit me but no xtra. Good mileage but EGT was to high. Started playing with timing about a month ago, best power at highway speed cost me some boost. So I purchased a 12cm turbine housing. Brought boost up some, egt down some. Called the shop back up and ordered compressor wheel and housing. Installation produced no results. I was convinced that I had a big preessure drop after JWAC aftercooler. Today while I was making preparations to get a pre-jwac boost reading, I just happened to glance into the jwac and the entire top surface of the core was covered with a black cottony-fibrous material. My engine was breathing through a small 1.5 inch hole in this stuff!
Long story short, After cleaning I went from 14psi boost to 25psi boost that comes on early. Egt came down 200*! Definately gathers up mph's faster than the 400 4 barrel that was in it. Cool down at shutdown is nearly non existant . All that I can figure is that there was an air filter failure before I got the van and I missed it during installation. Extremely happy now and high fives all around!bounce
Carl

1979 F-250 crew cab 4 x 4
4 bta with modified H1C
Cold air intake
ZF S-42 5 speed
Borg Warner 1356 x-case
Dana 60 rear
Dana 44 front
3.55 gears
255/85R16 tires (33.5x10.5)
Hydroboost steering and brakes
Custom 40 gal. fuel tank
Much more later

 

[Dougal]

That's excellent news.

Nothing like finding the source of a long bad headache, and fixing it easily.:dustin:

 

[Mikel]

I love happy endings

 

[tndonor]

Good to hear.......I hate all those little things that have such profound outcomes

 

[1340]

That's great. Nothing more satisfying than a simple fix.

 

[JimmieD]

Yeah, that's great news! But, I'm a bit confused: you say a 12cm exhaust LOWERED EGT's? That should have raised EGT's from the stock 16cm exhaust, not lower. Any good explanations out there guys?

 

[dieselcruiserhead]

Very cool Carl..!

 

[mooktank]

Yeah, that's great news! But, I'm a bit confused: you say a 12cm exhaust LOWERED EGT's? That should have raised EGT's from the stock 16cm exhaust, not lower. Any good explanations out there guys?

The higher boost lowered the EGTs. It helps take some heat from the fuel and lower temperature.

 

[Carl Donica]

Keep in mind Jimmie, that I had a pre-existing severe air restriction between turbo and manifold so I dont have true boost or egt numbers before I modified my turbo. This restriction probably also caused the high egt numbers that i had due to compressor wheel strain transfering to the turbine. After I cleared the restriction, max boost went up 11psi.
Carl

 

[4btDakota_Tx]

sweet beans bounce

 

[cgarr011]

what kind of difference in mpg are you getting?