Question for BJ74/13B-T owners (1 Viewer)

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Joined
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Location
Seattle, WA
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www.4wdtoyotaowner.com
I finally took delivery of the BJ74 and the exhaust piping is a whopping 3" diameter. Seems too big for a factory inline 4-cyl turbo. Not a lot of back pressure either.

Can anyone tell me what the factory piping diameter is?


Thank you!

Dave
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1"3/4----1"7/8 some areas around the muffler up to 1"15/16.

The noise must get tiresome. Turbo diesels require very little back pressure.


I run a dump on mine to help lower the EGTs at higher altitudes
SSPX0049.jpg
 
I finally took delivery of the BJ74 and the exhaust piping is a whopping 3" diameter. Seems too big for a factory inline 4-cyl turbo. Not a lot of back pressure either.

Can anyone tell me what the factory piping diameter is?


Thank you!

Dave

Its a large 4cly turbo diesel 3'' is ideal. Why would a turbo diesel need backpressure at all? Its not a old school carby v8 with longtube headers on it or something. It must be LOUD and sound crap, I added a muffler to mine. Add a 3'' dump pipe, wind the boost up to 20psi and jack up the fuel, they really hoot along then.
 
PIPE looks too short and must wear your ears out. Should be out the back or behind the rear tire for exit.

I run 3" and its fine you don't need a lot of backpressure for it. Make sure it has a nice muffler on it for peace on earth :)

I think from memory factory was 2 or 2.5"
 
Well right now the truck is gutless and I think the piping is too big, might be a factor to that. I know turbos need plenty of room to get the gasses out, but this thing might have too much. Especially if factory is 2".

Dave
 
Dave...all that gasser knowledge you have. Dump it. Really. Hit delete.

Then head over to Banks Power | Technical Articles There is the marketing...but ignore that, and absorb all the tech.

It's not because the exhaust is 3" that it is gutless. You've got piping there that will let things evacuate nicely. Start with the basics (do a valve set, couple of quick oil changes to flush it, change fuel, oil, and air filters, compression test). Then...start considering what you need to do with the engine to take advantage of that 3" exhaust (boost and fuel). If you have no history, consider an injector rebuild before going crazy. And install boost and pyro gauges while you're in the baseline stage.

gb
 
agree with Greg
forget you gasser knowledge, it is useless with diesel.
factory size is just under 2" (think metric)
you can run a diesel just fine with NO exhaust but i don't like it and neither will your neighbours.
i like 2.5" with steel muffler and resonator, the older i get the more quiet i like it.
i would second the advice of rear of rear tire and preferably on the center line of the tire so the air flow takes the exhaust away from the back and out instead of getting caught in the air flow up the back making the back black as well as getting a VERY STRONG diesel smell when you have the top off.
you have a great start to a fine exhaust system, nice mandral bends.

install a boost gauge, a pyro and an aftermarket water temp gauge. i sell a plate that mounts these gauges into the center just above or below the stereo. some people like them above, i like them below. once you have that installed then record the results and post them up. we will give lots of personal advice after we know what is happening inside the engine.

the 13BT is a torquey little bugger but it isn't a V8 by any means.

bikini top on its way, didn't realize the truck was on the water. sorry.

cheers
 
agree with Greg
forget you gasser knowledge, it is useless with diesel.
factory size is just under 2" (think metric)
you can run a diesel just fine with NO exhaust but i don't like it and neither will your neighbours.
i like 2.5" with steel muffler and resonator, the older i get the more quiet i like it.
i would second the advice of rear of rear tire and preferably on the center line of the tire so the air flow takes the exhaust away from the back and out instead of getting caught in the air flow up the back making the back black as well as getting a VERY STRONG diesel smell when you have the top off.
you have a great start to a fine exhaust system, nice mandral bends.

install a boost gauge, a pyro and an aftermarket water temp gauge. i sell a plate that mounts these gauges into the center just above or below the stereo. some people like them above, i like them below. once you have that installed then record the results and post them up. we will give lots of personal advice after we know what is happening inside the engine.

the 13BT is a torquey little bugger but it isn't a V8 by any means.

bikini top on its way, didn't realize the truck was on the water. sorry.

cheers

LOoks like crushers is right.

The 13B-T is a great little engine and is not gutless by any means I know I managed to pull over 1100kg of stuff up big hill(s) previous weekend with a blown headgasket and stuffed injectors. 3" exhaust with a muffler will make it quite quiet the exhaust you have now would have me driving over your little toy with my Volvo very quickly if you were my neighbour.

Get the techincal information done so help can be given

1. CHeck your injectors and compression also and the fuel pump before doing any more mods.

You can also look at running the exhaust out through the REAR bumper (side exit on a ARB styled bumper or clone) as we do for after market bumpers this protects it from being crushed and it sits just above the centerline of the tire but it does get drawn away. We follow the factory line for the exhaust I see yours is not following the factory line also. All the mounts you need are there.

GOsh a Gasser trying to make a DIESEL run faster yes toss out your GASSER tuning book and also remember they do not rev like PETROLS to 6000+ rpm.

If you have your 13B-T tuned right you can change up at 2500 and it will still pull like mad and shove you back in the seat especially with boost at 20psi and a modified fuel pump. Hultsy knows so do I :) DYNO of RED coming soon to prove it. (sometime between 24th-30th of this month). I wanna beat HULTSY's 13B-T figures :) hahaha
 
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you mean this type of power :) spinning sneakers with a gross weight of about 3300-3400kg on a steep wet and slippery track from a 13B-T with a 3" exhaust and no other mods.

like this from the recent trip.

YouTube - MVI_0600.AVI
 
And the GPs?

Gentlemen, I stand corrected and chastised. Fifty lashes with a wet trout the punishment.

I will do as you say, do basic PM, check compression and injectors, etc, and report back.

Can anyone tell me the glow plug part number? Marbles' excellent thread didn't have a BJ74 (or I missed it).
 
What glow plug?
 
For 12V 1986 BJ74 13B-T.
 
What I was gettin at was that the 13B-T doesn't have glow plugs.
It has a glow screen in the intake assy. The 24v screen heats up fine wired to 12v with manual push button control, just takes a tad longer... no biggie as the 13B-T only really needs glow when it's below freezing on a cold start. So it's not like you have to push the button every time you fire it up.
 
Badass. Thanks! Damn lucky diesel owners!
 
Get to know your machine!
 
Be mindfull of that exhuast ,
A mates turbod 2h troopy had the same exhuast set up ,we were towing a big boat down the freeway on a nice hot summer day ,the troopy stated making a slight vibration that got worse and worse ,when pulled up the was a massive bulge out the side of the tyre ,the heat had totally stuffed the tyre any more driving id say that tyre would have blown into a million hot sticky rubber bits.id say the egts would have been up there aswell
 
I have my 80 exhaust right there .. and there is no issues so far with my Toyo 315 on it .. ( about 3 or 4 years with those tires .. )

Edit .. I've ran it at 1300°F EGT ( pre turbo ) too ... maybe I'm just a lucky bastard :hillbilly:
 
in the past i have run the similar exhaust with no issues ... i suspect there is more to this story.
 
Well as I get the old diesel run out of it, and put in fresh filters, she's coming to life. The old gal only has 192,000km, so I haven't done a compression check yet, plus she starts right up when cold with the barest hint of white smoke. I think it may have more to do with it being a slushbox. Or gears. A set of 4.88s would liven things up a bit.

I'm keeping the 3" for now :D
 

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