hi all
new and first post, so dont flame me too bad

found out my 89 7 series turbo is actually a garrett t3
i thought they came with a mitsu? (oh well)

i cant leave well enough alone, i searched online, but didnt find more detailed specs anywhere

i am wondering what are the stock t3 specs (wheel & housing size) that it came with?

also i wonder what direct t3 upgrades can be done, budget ones of course, like upgrading to use a t-bird t3 60 compressor side wheel + housing (for example)

okay LMK, thanks

AFAIK, the automatic transmission cars came with Garrett turbos until '89, but at some point they changed to T25s, which look similar to the T3. Parts are not interchangable. I want to say that this point was '88 for the 740 cars and later (if at all) for the 760/780 cars, but James will likely be the best source of information on this. Maybe he'll chime in.

Don't lament the lack of Mitsu - the early Volvo Mitsu turbochargers were really tiny on the intake and didn't allow lots of upgrade room. After '90 or so they got a bit better balanced, but are still very small and restrictive.

If you DO have a T3, it has a 50 trim compressor with a .42 A/R housing, and a .48 A/R turbine housing. You could stick a bigger compressor on there, but until you increase the flow capability of your engine, intercooler, and exhaust, you're probably fine with what you got. I've run 15 psi on that turbo, and know it's still capable.

Automagic sedans got a garrett until 89. Some of the '89 T3s have the oddball .52A/R compressor housing (but with the same wheel Matt mentions inside) with a plastic nipple for the WG hose that likes to break off once in a while and toast a once perfectly reliable old lady driven car that runs regular gas (it pings a lot before the boost cut basically).

Wagons and manual gearbox cars got a TD05 12B mitsu thing late 87-89. No great loss not to have one of those. The mitsu water cooling is better and they last a really long time on soccer mom driven cars, which is all they are good for IMO. I think water cooling is useless to me and just adds a lot of really hot water to the cooling system, however. Most mitsus can't be run dry due to how thin the casting is in some places and often crack through the center section from stress.

No motorsport cars use mitsu garbage except mitsus for the most part. I will say that the v-band that holds the exhaust housing to the center on a mitsu is a VASTLY better way to hold it on there then lots of crusty bolts that you can only access with an open-end wrench in places like garrett uses.

okay, thanks for the good information guys

i dont think the mitsu are bad turbos, i just thought this model was one
didnt know for sure till i looked closer that it was in fact a garrett (auto sedan)
for my winter car its fine, but of course i cant leave well enough alone

i've done (budget) upgrades from other cars before, upgrading wastegates, or i've run a 50 trim turbine with upgraded to 60 trim compressor before and it worked out well

i've got an extra intercooler that will fit and upgrade things some
i'll probably install a AF meter before upgrading the turbo, so i can check on things & upgrade injectors when needed

what injectors a the swap in for mild upgrade the t3 turbo?

any issues or limits with the stock fuel ecu, with intercooler or mild t3 turbo upgraded?

thinking this was a mitsu car, i actually bought a couple week ago locally a td05-16 (from an evo8 car) to upgrade this, but of course i was lazy and didnt double check first that this was in fact a mitsu car LOL

if anyone is looking for one let me know, as i'm going to sell this one now and get some t3 parts instead
(td05-16g6 - really clean, openings covered, clean oil in bearing channel, no shaft play, has banjo lines/bolts/washers included - $75)

my next BIG performance upgrade is winter tires

i've seen in swaps, the coolant feeds on t3s and t4s just blocked off before & left dry, seems to work out fine?
i suppose you could do the same for a budget td05 swap if you wanted? as long as the oil pressure is good, and clean, then it will cool the bearings
many older t4s didnt have any coolant passages at all

Crap, I had a big response going and lost it. I'll try to duplicate it.

Your injectors are good for at least 185 RWHP - I know this and have the dyno plot to prove it. I've heard people say that they're good for over 200 before they start to go lean, but I can't verify. I think Athal made 205 on the next size up (31 lb/hr instead of 29 lb/hr) without trouble, but it might have been on the stock ones.

You can install injectors up to 35 lb/hr without trouble, but you'll have to install a resistor (330 ohm, I believe) into the AMM signal line to compensate. You may be able to go with bigger injectors and more resistance, but you'll probably start to encounter starting issues or driveability problems. You can also install a 4 bar FPR from a 2nd gen turbo Dodge, which will increase the injectors' flow by about 15%, but it puts more stress on the fuel pump and also reduces it's output. You would still have to do the AMM mods. I woudn't do any of this stuff until you get to the point where you need more fuel flow.

The fuel pump is good to about 330 hp at 0 psi boost, but with added pressure it reduces the flow. Say at 15 psi you've reduced flow by maybe 20%, so the pump is reasonably safe to 260 horsepower, assuming it's in good shape and can still flow the rated amount at the test pressure.

The intercooler isn't great, so upgrading that can help. Ditto on the exhaust manifold. Any mods you can make to help airflow will improve power without the need for added boost. Camshaft upgrades, exhaust manifold, downpipe & exhaust, intercooler, port & polish, big valves, etc. IMHO, all that stuff are things you should be thinking about before you stress about a bigger turbo, unless you've got the T25.

The ECU supposedly goes into a "rich safe" mode above a certain airflow. I have a chipped ECU that enables all of the AMM range, and gets into a slightly less safe, more powerful mode. It is still safe, but not as overly stupidly safe as the stock one. I have never really enjoyed the chipped ECU - there's something wrong with my setup and it just doesn't work too well. If you want to try it out, feel free - I'd sell it. I swapped between it and the stock one on the dyno, and the chipped one made 10 extra horsepower.

There's an overboost switch just above the clutch pedal that cuts fuel above I think 12 psi. You can delete it if you wish, or you can install a different switch with an adjustable setting.

Does your TD05 have a 3 bolt housing or 4? Is it the standard Garrett T3 pattern like Volvo uses, or the goofy Mitsubishi one?

Regarding the coolant, as James says, the Garrett turbos bearing housings are thicker and more resistant to heat. The MHI turbo is thinner and relies on the water jacket. Don't run an MHI without water, though it's an option with Garrett. I'm not sure I'd run a watercooled Garrett without water regardless, though apparently it works. It's false economy to eliminate a few hoses & fittings and forsake the turbo to guaranteed early failure.

more great info, thank you!

i dont intend to go crazy, just a bit more pick-me-up, and of course with minimal budget, for now without taking to much apart
about 200hp would be a great target i think, dont want to over stress the current head gasket anyway

good to know about the injectors, i'll install a simple AF meter anyways just so i can monitor things

so you can run 31 lb injectors fine without modifying the mass meter signal (resistor)?

where is the overboost switch (above clutch pedal you mentioned) located on my auto?
if its vac operated, then i could use a bleed

the question is how much more airflow can it take before going into an over-rich (safe) mode? and how to prevent that?

i could always run a hobbs switch, and install 1-2 injectors downstream for added fuel when over 12psi mark
but i'd have to limit the ecu to seeing 12psi before doing that
since there is no map sensor with amm, i'd have to figure that part out yet too?


this evo8 mitsu td05-16 has a v-band clamp to attach to the manifold, and being a td05 the turbine wheels and clamp are standard fit, so would fit direct in place of your oem td05-12

the compressor housing of the 16g6 is of course noticeably larger, and can be clocked into what ever orientation you want
the comp housing inlet is a typical slip on hose style (about 2.5-2.75") and the outlet (about 1.75-2") uses a neck extension (2 bolt attachment) which then is slip on hose style as well, kinda like the t-bird/svo t3s use, or you could even weld directly on a short neck tube to fit exactly how you want it to

ya, i agree with you on keeping the coolant lines, personally i wouldnt delete them, i just mean i've seen it done

its actually pretty easy to keep all that, using the td05 oem banjo fitting/lines, you can just cut them off, then clamp (double clamp IMO) some good hi-press hose over the tubing, and you could do that for the oil feed line as well
the oil drain back is probably exact same fitting you have already too

should be a pretty straight forward swap i think

185-200 RWHP makes for a pretty fun 700 series. You've also got the K block with the crappy connecting rods, more than likely, so you don't want to go nuts with power.

The 31 lb injectors are less than 7% different from stock, so adding them doesn't require any changes. Adding the 4 bar FPR, or going to 35 lb/hr injectors is 15-20% change, and is a bit much because the stock computer already goes pretty rich once you pass the existing airflow boundarys.

With the stock chip/injectors and at about 10 psi boost on the TD05-12B turbo, I was making about 11:1 air fuel ratio from 3200 RPM to 4400 RPM, and then there was a sudden enrichment to about 10.3:1 AFR from there to 6200. With the chip and no other changes, it ran a bit leaner (0.1-0.2:1 leaner) but then it never had that sudden dropoff, until it started to get a bit richer at 4800 RPM or so. It never got as rich as the non-chipped ECU, though. The result is a slight increase in torque from 3000 to 4400 RPM, a fairly substantial increase (20 ft-lbs) between 4400 and 5200, and back to a moderate increase from there to 6200 RPM. Horsepower was about 10 hp fatter from 4400 RPM to redline. I made one more pull at 12 psi, and it made about 10 more horsepower again, to 185 peak with the chip.

I also tested the same engine at stock boost with the stock ECU, and it stayed between 11.0 and 12.0:1 AFR throughout the entire run, without any sudden dropoffs. Therefore, the stock ECU will go out of it's boundaries somewhere between 6 and 10 psi, depending on the mods done to the engine. At 10 psi, that happened at around 4200 RPM on my engine.

The mods to this engine were a Nissan UD intercooler, an Enem V15 turbo cam (same as the IPD turbo), and a 3" exhaust with a stock downpipe. It's a manual transmission, and all runs were done in 3rd gear.

If you wanted to add secondary injectors, you could do what some folks have done, and install a couple Volvo 240 Turbo cold start injectors into the intercooler cold side pipe. Ideally you'd weld in an angled mount, to spray the stream downwind, towards the throttle body. Doing this opens yourself up to fuel distribution problems, so it's not a great idea. The intake manifold is designed to flow AIR, not air and fuel. Anyway, switching the injectors on at staged pressures will help richen up once the injectors fall off, but be sure you don't have a K block with the skinny rods. Do a google search for how to identify this block.

The overboost switch is in the same place in all cars, above where the clutch pedal would be. If you want, just disable it - I'm sure you'll be keeping an eye out for blown wastegate hoses and such, with your eye on the boost gauge and/or your ear tuned to knock, right?

The ECU doesn't see boost at all. The ECU only "sees" what the AMM tells it, along with the coolant sensor, tachometer signal, and the knock sensor. You don't have to limit boost to the computer, only to the overboost switch.

I am not sure that all TD05s are interchangable like the Garrett T3 is. Not to mention, the Volvo TD05H uses the smallest turbine housing of that range. You may be have been able to get them to fit, or maybe not. I'm no longer running this turbo, or this engine for that matter, so I can't test it for you

yup, sounds all about right
i'm going to keep it mild, so 180+hp is a good goal

usually most oem ecus can run about 10-15% max outside of their stock medium, so should be safe
you first hand dyno info is great help - thank you


yes, from what i've checked on the 16g (evo8) is smaller turbine and compressor size, the turbine wheel is the same, just the evo had a larger AR housing (8.9cm2) so would be a direct fit into the (7cm2) volvo td05-12 housing
the earlier evos (evo3-4) used the "big" 16g, while the later evos (evo8-9) used the "smaller" 16g so should be correct

so if anyone wants to grab a nice td05 snail for upgrade cheap LMK