twins on a 6.9

[dieselfreak0193]

i think i might have posted this in the wrong spot so ima try it here. i dont have a ford diesel but a buddy of mine has an 1984 f350 with the 6.9 in it. i have a couple questions and am hoping that somebody might be able to help me out cause im not familiar with them. i have a cummins but not saying that ones better than the other or anything. anyways how do you turn up the fuel on one? is it like the 7.3 powerstroke or can you do it mechanically? secondly would say a stock intercooler off like a 95 PS be easy to rig up on the 6.9? and thirdly hes interested in running twins and my thought is would it just be easier to run one off each side and then tie them together? any help would be appreciated. thanks

[nccatfan]

Be careful when putting those turbo's in (May have to fab that setup... I've not seen twin turbo kits for the 6.9), those head gaskets don't like boost very much. Should look into head studs if you go thru with that.

[dieselfreak0193]

ok thanks probably wont be pushing very high boost so i never thought about that. definately will be a fab setup though. thanks for the input

[nccatfan]

Yeah, many of the later IDI turbo'd 7.3's had head gasket and I think EGT issues. I have seen a kit for a single turbo setup on the IDI engines... Was in one of the diesel mag'.s a few months ago.

While I'm at it I'll be the first to say !

[dieselfreak0193]

well thanks i got the tools and machinery to rig up custom header pipes and intercooler piping and all that good stuff im just trying to get as much info as i can on this motor though before i dive into this. what about turning the fuel up? is that all controlled by oil pressure? i know they are indirect injected but thats bout it lol. definately am interested on learning bout these and the powerstroke motors. when it comes to fords and chevys i dont know crap lol

[nccatfan]

Cool. But the IDI and Powerstroke engines have nearly nothing in common. Your 6.9 is classic definition of "old-school" diesel! You have a rotary mechanical fuel/injection pump that operates the injectors (which are basically glorified hi-pressure check-valves). The 7.3 and 6.0 PSD's have HEUI ("Hydraulic Electronically controlled Unit Injector") systems (6.4 is common rail).

As for performance tuning a mechanical diesel... well, hopefully someone else can chime in for that! Turning the fuel up is one way to gain some power. Upgraded pumps and injectors may be available if you look hard enough.

[66Bronco]

Also, the Powerstrokes prior to the '95 model year didn't have intercoolers.

[Dave]

Originally Posted by 66Bronco

Also, the Powerstrokes prior to the '95 model year didn't have intercoolers.

Actually prior to 99 they didnt. None of the OBS trucks had intercoolers from the factory

[dieselfreak0193]

well ive been researching and i now know how to crank the fuel up. have come to realize that twins arent a good idea without major upgrades. so gonna run a single with head studs and push round 15 psi would probably be a safe number to run. i didnt know that they were non-IC until 99. ill rig something up. now what size pipe would u guys think would be good to use to make header pipes?

[dieselfreak0193]

Originally Posted by Dave

Actually prior to 99 they didnt. None of the OBS trucks had intercoolers from the factory

now what does OBS stand for?