1991 LJ78 3b turbo swap.

yotahed · 01-26-12, 05:31 PM

If you got time to post a pic, i wouldnt mind havin a look. Just looked like a simple hook up is all. This build is definitely testing my skillset, Any and all help and advice is greatly appreciated.

Cheers!

yotahed · 01-26-12, 05:38 PM

Some pics of the interior and shift console.

yotahed · 01-26-12, 05:42 PM

And the engine bay and clutch hookup

yotahed · 01-26-12, 05:48 PM

Fixed my throttle linkage today. The cable end loop was broken off and the whole center section cracking, so took a couple 1/8 thick 12mm washers and welded the works back together. works like a hot d@mn. shaved the plastic sleeve down to account for the extra width. I was kinda worried about this bit...
Now gotta make a new bracket for the actual cable off the valve cover.

yotahed · 01-28-12, 03:23 PM

Figured out my manual shutdown routing. Im putting the knob in the shifter console and running the cable along the frame to the front and making a cable stay above the old EDIC location out of 1x1 angle steel. should work good. I might weld the little ball knob on the IP arm to get rid of the slop. but we'll see how she works as is. Ill keep my oil light and stock pressure guage hooked up, as well as a mechanical maybe off the turbo line.
Installed my racor filter and ran new lines to it.
Working on my manual glow and manual start relays and switches.
Will post more pics when i get a little more done.
Not long now!

yotahed · 01-31-12, 07:38 PM

Got the recored radiator in, and plumbed, moved the heater feed to the intake side of the motor. Hooked the aux temp sender to the 2nd heater outlet below the Tstat.
Got the shutdown cable in and hooked up, works well, kinda stiff tho...
fired her up for a bout a half hour, checked for leaks, fixed them, the temp didnt get up past 135-140F, thinking maybe the Tstat is stuck open? How long for the 3B to get up to temp idling?
Got a shifter arm from a RHD BJ60, tested the clutch throw/release while running, shes a beauty.
Gonna finish up the rear panhard drop tommorow, and the throttle cable mount, pull her outside, and put the grille and bumper bits back on.
It's comin together boys. Im stoked.
What guage wire should be used when hooking up a manual glow solenoid? Is 10AWG sufficient? doesnt seem to get warm or hot in 10 seconds of glowing.
Its a tight area on the RH side of the engine with the alternator,pwr steering, vacuum hose, turbo, clutch and brake masters, all in very close proximity.
Exhaust will be the next big project, I have a 3" DP and exhaust leg off a supra and got my flexi in the mail today.(with my tiny tach!) I hacked the exhaust off at the DP, and Im gonna tack together something out of the remaining bits to get it going along the inside frame rail maybe. Do a lot of you guys go out the fender well like a stock LJ? I never like that, so im gonna try and do it on the inside.......
Stay tuned for pics tommorow.
Cheers

crushers · 02-01-12, 03:55 AM

at idle, depending on how low the idle is set, can take quite a while to warm up to operating temp. you have a lot of cast to heat ...

Radd Cruisers · 02-01-12, 08:51 AM

You need a return spring on the clutch release; it just won't work properly without it.

A 3B will never get up to temp idling. At best, it will just barely lift the pin from the stop on the coolant temp gauge. Run it up in revs a bit, and it will get warm (but all this depends on your fuel settings).

~John

yotahed · 02-01-12, 10:39 AM

The return spring for the clutch fork? okay, are these still available, or can i use a big fat generic spring and make that work?

Radd Cruisers · 02-01-12, 03:49 PM

Yup, still available. It's easy enough to get the Toyota unit, and it's got the right tension etc.

~John

yotahed · 02-01-12, 06:01 PM

Thanks John,

made up a throttle cable mount using the 3b bracket on the valve cover. bolted that to a peice of flatbar 6" or long and bolted the flatbar to the valve cover. worked better than I thought.

I pulled of the shop under 3b power today.

Twas a good feeling.
Damn does it shake when cold lol.
Put the valence, hood latch brace and grille back on. Had to trim down the hood latch cross brace and toss 2mm washers under the bolts to clear the rad. everything still fits as it should otherwise. starting to look like a truck again.
Finished up the rear panhard drop bracket, and welded a cross brace to the opposite frame rail, similar to the front. Rear axle is now centered and panhard is d@mn close to level. sweet.
sorry about lack of photos, seems to get dark before i think about cameras....
I get some up tommorow before i start on anything and forget

cheers all.

yotahed · 02-15-12, 09:59 PM

Took it out for a spin, gears work fine, clutch is good, engine is smooth...
cant help but notice how fast the EGTs go up, like im watching a slow boost guage.. is this normal for a 3b? i got the prob pre turbo right below the flange.
I also noticed the turbo doesnt spool untill 2800 almost 3000rpm, looks like I have a supra variant. damn. Im looking at a garrett m24/ t25 or something similar. Whats the optimum AR for a 3b? anything under .48 for both hot and cold sides?

Aside from underboosting woes- truck runs awesome feels awesome, sounds cool. Everything but the exhaust and new shocks is finished, other than the sick intercooler that arrived the other day, but thats post for another time!

Temp gets to 180F and stays just a hair above (185?)
EGTs climb very quickly from idle to about 800 in 2nd, 950 in 3rd and 1000 in mid 4th, no highway yet, and not flooring it. They go up much quicker when wide open. I think this is partly because of the slow spool of the turbo? trying to mve too much air with not enough exhaust. exhaust is simply a dumpipe with a 1 foot section of 3" pipe
Havent touched the fuel.

yotahed · 02-15-12, 10:02 PM

more pics

yotahed · 02-16-12, 12:00 PM

Im looking at a T3 garrett, exhaust .48, compressor .42
This sounds like a decent match for a 3b? should spool quite quickly.
I think im gonna try it as it is oil cooled only, way smaller than the ct26(exhaust housing is half the size) and is internally wastegated with a 2.5 inch vband downpipe adapter. Got a ct26 to t3 adapter off ebay. We'll see what happens....
anyone wanna buy a 54 trim CT26?

cheers

cicak · 02-16-12, 03:29 PM

turbo spooling up at 2800rpm is WRONG on a 3B should be cutting in (spooling up) at 1600+ and full boost by 2000rpm go read up on 13B-T specs. I'm already changing up at 2500

What TURBO are you running. my 13B-T is running a 7M GT26 turbo

Cut a video so we can see .

yotahed · 02-16-12, 03:59 PM

Im using a CT26 in 54 trim ( intake bored out, bigger wheel etc.) off a 7mgte supra i believe. I kind of figured it was too big, but it was cheap. Im getting a T3 .48 exhaust/ .42 compressor, should be here in a few weeks. I have a video, it shows how hight the egts get and quick. not sure how to post it. you can hear the turbo spooling its very loud, but its a lie because the guage doesnt come alive until under heavy load( bogging in 3rd or 4th), or revving the piss out of it from 2nd to 3rd.
I would just drive it till the new turbo arrives, but the EGTs get so high so quickly, im kin of discouraged to take it very far....

yotahed · 02-16-12, 04:34 PM

heres a link to a you tube video. quality is terreible as are my camera skills but is shows how quickly the egts climb. and max boost i hit at 2800-3000rpm was 10 for a split second mostly wont boost past 5 at 2800 wide open.

LJ78 3B turbo, First ever? - YouTube

yotahed · 03-01-12, 09:33 PM

New T3 turbo arrived today.
Shes all shiny and purdy. Ran into a snag installing with the shoulder length of the turbo studs on the exhaust manifold. Nuts holding the adapter plate have to be washered up to clear the shoulder sticking past the plate and just barely interfere with the T3 flange. SO CLOSE!! Will have new studs after the weekend, thatll sort that out. also need to grab a -4AN to 1/8 NPT adapter for the feed line. Still waiting for the 2.5 inch Vband clamp for the downpipe off the turbo. stupid mail.
Turbo is about half the size of the CT26, looking forward to the results.

I also installed a set of 79 series IRONMAN front springs in the front and rear. Figured the extra weight of the engine would warrant a fatter spring. Guess not, ride is quite rough, so these are for sale in the classifieds if anyone is interested. They lift a 79 2" and gave the LJ a 4.5 " lift
Perhaps for someone who carries cement or construction gear around a lot theyd be good.

I finally found the proper PN's for ironman LJ springs TOY048B Front and TOY049B Rear if anyones interested. Ill be gettin these shortly.

Also picked up a hood scoop from a WRX, nice and low profile, colour matches almost perfectly got lucky i guess
Post some pics up soon.
Later Gents
cheers to all

yotahed · 03-03-12, 11:46 AM

Got the hood scoop hole cut out and mounted it loose. looks good. gonna do it flat black with some retro toyota-esque design on the hood. still needs a rubber seal around the bottom, threw some new hella spots on her, good price, free.
Any one heard of cobra springs, any experience with them? they have a 100mm lift set for the LJ that i am seriously considering.

cheers

yotahed · 03-04-12, 09:41 PM

Got the new turbo all bolted in, oil lines hooked up, re plumbed intake pipe.
Boost now comes on around 1600(5-6lbs)- 2100(11lbs), depending on foot pressure. Egts climb not quite as quickly but still fairly quickly, They topped out at 1000F in 3rd going about 60kmh uphill about 2800 rpm. If I hold my foot to the floor slowly creep to 1100F.
Is it common for the Ex temps to go up quite quickly with a probe in the manifold?
I remember on the 2LTE the probe was post turbo and the climb to 1000F was quite slow on flat ground flooring it, on the 3b on flat ground it climbs quite fast.

I also Installed a autometer electric oil pressure gauge on the tee that feeds the turbo, coming from the old sender hole. Im getting 50lbs at cold start up, dropping to 10-12 at warm/hot idle(175-180F)
When accelerating goes up to about 50lbs or so. Normal?

Might turn the fuel up a 1/2 turn and see what happens. time to play!

cheers