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562dragnhra 08-15-2009 07:12 PM

Allison at545 6.9 diesel
i have a 6.9 diesel hooked up to an Allison AT545, what rear end gearing do i need to run??? right now i have a 3.00 rearend. 1st and 2nd are loooonng!!! and i have a RPM gauge that i got at the junk yard wondering how to wire it???

David85 08-15-2009 08:05 PM

Never looked up the ratios before. Looks like a nice tranny. I like the tall reverse ratio.

First 3.45:1

Second 2.25:1

Third 1.41:1

Fourth 1.00:1

Reverse -5.03:1

Forward 3.45

*Gear ratio does not include torque converter multiplication

What is the vehicle? a bus I assume.

I would say 3.00:1 could be a good ratio to preserve highway fuel economy, but it really depends on the total weight of the vehicle. You might have to go with lower gears.

562dragnhra 08-15-2009 10:45 PM

well the whole setup is on my 1977 F250,

David85 08-15-2009 10:50 PM

Originally Posted by 562dragnhra (Post 7833615)
well the whole setup is on my 1977 F250,

Oh......alright then, You will love it with 3.00 gears.

Thats gonna be one hell of a rig!

GenLightening 08-15-2009 11:22 PM

Originally Posted by 562dragnhra (Post 7832979)
and i have a RPM gauge that i got at the junk yard wondering how to wire it???

Was it out of a diesel? If so, you will also need the sensor that mounts in the IP housing. The wiring is pretty easy. The gauge has 4 connections, 2 are grounds, as is one of the leads from the sensor, the Sens connection will go to the other lead from the sensor. The last connection is 12v+ and goes to a power source.

562dragnhra 08-15-2009 11:35 PM

alright kool, oh and ya the tach came from a diesel,

ford390gashog 08-15-2009 11:50 PM

how is the ground clearance with that huge trans pan?

562dragnhra 08-16-2009 12:15 AM

Its level with the frame, and it has tha big deep pan too

1994diesel 08-16-2009 12:26 AM

ooh, pictures would be cool!

562dragnhra 08-16-2009 01:05 AM

i dont know how to post pics on this forum,, i took my truck to get my exhaust done out the hood with a 5" stack, and im running banks sidewinder turbo too

David85 08-16-2009 01:36 AM

You have a couple of options for posting pictures,

1: set up your own gallery, and upload the pictures there. Once in the gallery, you can post them in the thread by copying and pasting the "forum posting code". It will be shown as a link in your gallery below each picture.

2: if you have a file hosting account at a place like photobucket, you can post them from there.

LCAM-01XA 08-16-2009 03:34 AM

Originally Posted by 562dragnhra (Post 7833880)
i dont know how to post pics on this forum,, i took my truck to get my exhaust done out the hood with a 5" stack, and im running banks sidewinder turbo too

Hood exhaust is highly illegal for a street vehicle in any state, keep that in mind if you ever plan on driving the beast on public roads.

Mat J 08-16-2009 08:59 AM

go to and upload pictures then copy the img code here, we want to see this beast :)

562dragnhra 08-16-2009 04:52 PM

Really its illegal??? i see some trucks have them, dnt have oics of my truck yet but i will post it up once i get my truck done guys:-drink

Mat J 08-16-2009 08:45 PM

exhaust has to exit behind the b pillar on the cab for on the road use. I belive that is every state.

LCAM-01XA 08-16-2009 10:45 PM

That is correct, the reasoning behind it is that under the right conditions exhaust fumes can severely limit your visibility if the exhaust exists before the windshield. The only exception to that are Class 8 straight trucks with tanker bodies on them, they often have the muffler right behind the front bumper with the exit on the passenger side, this is so if there were ever any sparks to come out of the exhaust they cannot ignite any vapors from any flammable liquids the truck may be carrying. A pickup truck does not haul flammable liquids, so you do not qualify for this exemption - your exhaust needs to exit behind the cab, whether you run a stack or a side exit or all the way out back.

AndysFords 08-17-2009 01:12 PM

While they are right, some states do not care enough to check things like this? WHat state are you in, does it require a yearly inspection and/or smog? If so you probably need to fix it, but states that do not I would not worry about it. I definetely would not do anything until someone made me.

1994diesel 08-18-2009 12:07 AM

I have never seen anyone in these parts of cali run there exhaust like that, i have seen every other way though. A lot of people run stacks out through there bed.

562dragnhra 08-18-2009 12:43 AM

I live in californis Snat Fe Springs, well my truck is an 77 F250 with the 6.9 diesel, i dnt think cops would even look at my truck

1994diesel 08-18-2009 12:54 AM

hey man if you wana do it, do it, i think it is awesome.

how high will it be coming out of the hood?

I dont think the cops would give you any trouble, just take it nice and easy when they are around, lol i take it pretty easy around cops with my straight piped '94 and the cops never give me a second look.

562dragnhra 08-18-2009 12:59 AM

Just below the roof, i think i will be good, i have a 69 mach I with a big ass scoop and cops just look at my car and say thats kooool, so dnt think they would do nothing

1994diesel 08-18-2009 01:02 AM

ah, just below the roof. I would be bugged about all the carbon soot building up on the window and roof. lol

562dragnhra 08-18-2009 01:05 AM

ya i know but i dnt want it that tall either cuz to me it looks kinda dumb, plus the pipe has an angle so i can point it to the side of my truck, hope the asmoke dnt go into the car :eek:

562dragnhra 08-18-2009 01:16 AM

Is the Banks Side winder turbo good??? right now the truck is at the exhaust shop putting the exhaust done and also making that turbo intercooled too, hope that would add couple of horses

David85 08-18-2009 01:35 AM

That is a sweet truck. 2 tone color, trim package and everything. My dad had a 75 camper special that looked identical to yours in body and paint. 390 on LPG though.

Nothing wrong with banks, but fitting the turbo might be a challenge in that truck. I heard some guys had to hack the firewall to make it work.

REALLY interested in the intercooler you are doing in this. To my knowledge there are no intercooled turbo diesel IDI trucks from the 70s running around. I've seen turbodiesel repowers before, but never an intercooler (or allison for that matter!).
You are breaking new ground.

562dragnhra 08-18-2009 01:41 AM

well the motor and tranny are in, also the turbo, just had to make a 3" body lift to my truck to make the 6.9 to fit just right, i barely realized im the only one that im running a 6.9 banks turbo with an Allison at545 in a 1977 F250, i will post pics on thursday on my intercooled banks and the hood stack, maybe a video

WEST AUSSIE 94 250 08-18-2009 04:54 AM

Over here the exhaust must exit 1 foot behind the last opening window. With my slide open rear window that means no cab mounted stacks at all. The reasoning is not so much vision but exhaust fumes entering the cab and suffocating the people inside. Carbon dioxide and cabonmonoxide have no smell and so can sneak up on you. Fact is though if your carefull probably would look pretty cool and most cops wont care or know any differently.

Dave Sponaugle 08-18-2009 08:38 PM

The fumes and behind any opening into the passenger compartment is the reason and rule here.

Unfortunately, the first rookie straight out of the acadamy that sees you will probably be pulling you over.

Those trucks with stacks out the hood are pulling trucks, not street legal.
And those guys are not in the truck long enough for the carbon monoxide to get to them.

joe f350 08-18-2009 08:46 PM

i saw ur motor dude it looks brand new

562dragnhra 08-21-2009 12:44 AM

Hey guys i have a problem with my truck now, its the fuel pump i think cuz my diesel runs out of fuel and shuts off, i have an electric fuel pump "Purolator Fuel Pump: Universal; Electronic; Solid State; POSI-FLO(R) Pump; 1.5-4 PSI; 25 GPH; 95 LPH" from kragen, i think i need more PSI right??? and i noticed when it shuts off i stand next to the fuel filter with the fuel pump on and notice that it makes a sound that the filter is filling up with diesel fuel, meaning the filter goes bone dry, and yes i do have diesel fuel in my tank :) Any ideas???

joe f350 08-21-2009 01:06 AM

u nrrd 9-10 psi to run the truck

562dragnhra 08-21-2009 01:16 AM

are you sure??? cuz kragen has the same Facet Posi flow that its rated from 4 to 7 psi and 32 GPH, would that work???

LCAM-01XA 08-21-2009 01:44 AM

Originally Posted by 562dragnhra (Post 7852286)
are you sure??? cuz kragen has the same Facet Posi flow that its rated from 4 to 7 psi and 32 GPH, would that work???

That one will work good. The 9-10 psi Joe is talking about is too much, right there at the borderline of throwing your timing off actually.

562dragnhra 08-21-2009 01:54 AM

Sweet thanks!!! but will it work with the banks sidewinder turbo i have on my 6.9 diesel????

Skip1970 08-21-2009 02:04 AM

wheres all the pictures?

562dragnhra 08-21-2009 02:15 AM

itson the right side under albums

Mat J 08-21-2009 06:12 PM

yeah it will work with the turbo hook up a pressure gauge at the fuel filter and see how much psi you acutally get there I think the stock lift pump is 7 if I remember reading correctly.

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