[Dat82supra]

Hello everyone I really want to turbo my mk2 but I’m not sure if where to fit the hardware my question is where should I mount/find an intercooler that will fit or should I get a used one from a mk3 Supra I don’t have a budget with this I just want what’s best for my car so if you guys could help point me in the right way that would be greatly appreciated if possible link websites that would help me

 

[dannoxyz]

Greetings & Salutations !!! 👋

There's A LOT of options for every aspect of turbo build. I have yet to see rear-mounted turbo!

You can learn more by reviewing these sections:

5MGTE/6MGTE/7MGTE - turbo forum

Place to discuss M series turbo upgrades & engine swaps

www.celicasupra.com

Aftermarket Engine Management / Electronics

Standalone/piggyback computers, MAF conversion, ignition discussion.

www.celicasupra.com

 

[4SFED]

my question is where should I mount/find an intercooler that will fit

That's really two questions - mount it in front of the radiator/find one that fits there.

should I get a used one from a mk3 Supra

That sounds like another question - a Mark 3 is commonly used as a donor.

I don’t have a budget with this

You better have a budget before you do anything else.

I just want what’s best for my car so

Research.

if you guys could help point me in the right way that would be greatly appreciated if possible link websites that would help me

Start here

 

[Flyin' Hawaiian]

Along with the other posts above, its been done a thousand times, and yes, you'll need a budget for it! Here's my scoop after doing this to my 6MGE a long while back, its quite easy to do:

exhaust manifold from 7mgte
ct26 turbo
Oil return lines needed for turbo, they go to the oil pan (return line) and oil filter mount that allows you to tap into the filtered-side (feed line to turbo).
RRFPR (research this site for which ones work well, I had a Vortech iirc, don't recall the rate of rise though)
intercooler, recommended but not necessary, although you really should have one to keep charge temp down
custom exhaust from turbo.
boost gauge, another not really required but good to see what's going on
blow off valve
a/f wideband gauge and O2 sensor, definitely required if you want to keep that engine healthy

While its not a ton of stuff, this will cost you at least 2 to 3 grand to do properly. There's a lot of little stuff you need, such as gaskets and a custom exhaust plate for the ct26 exhaust side so you can weld up an exhaust system to it. The ecu will work with a turbocharged application, but it runs the system in open loop mode, meaning that there's no input data from the intake's MAF once it exceeds the flapper door's resistance. It then just uses the oem's O2 sensor, water temp and throttle position to adjust timing and fuel rate.

Now, for this to work correctly for the long term, you'll need to upgrade tons of stuff like ARP head studs and other items, and you can't just beat on it like its a drift car all day long. If you want the car to really last, I suggest not doing the turbo and just enjoying the car the way it is. And if its in good shape, it'll be worth a hell of a lot more bone-stock than it will be with all sorts of stuff added to it!

 

[Atl_Racer]

Hello everyone I really want to turbo my mk2 but I’m not sure if where to fit the hardware my question is where should I mount/find an intercooler that will fit or should I get a used one from a mk3 Supra I don’t have a budget with this I just want what’s best for my car so if you guys could help point me in the right way that would be greatly appreciated if possible link websites that would help me

Whats best is to buy something made for the car like a bolt on kit. And like Flyin Hawaiian said, its not going to be cheap. Know how much youre willing to spend because it can get expensive. All the little things like hoses, fittings, gaskets, ect. They add up really fast!

 

[dannoxyz]

The ecu will work with a turbocharged application, but it runs the system in open loop mode, meaning that there's no input data from the intake's MAF once it exceeds the flapper door's resistance. It then just uses the oem's O2 sensor, water temp and throttle position to adjust timing and fuel rate.

Open-loop means it ignores O2-sensor. This occurs in bone-stock factory configuration too when you're at over 80% throttle or so. If you've got O2 meter or wideband hooked up, you'll see that that AFR dithering across 14.7:1 stops and mixtures goes rich.

At this point ECU still uses AFM signal to look up injector pulsewidth on map (rich mixture). However, once AFM maxes-out flapper-door, ECU still uses AFM signal, and lookup-point is pushed to edge of map. Meaning extra air-flow above stock cannot be measured by AFM. So if you've got boost on top of 1-atm, AFM can't tell ECU it's got more than WOT, so it just injects whatever fuel-value is stored at WOTxRPM on map. So resultant AFR will be lean because you've got more air than stock that ECU doesn't know about.

ECU still using AFM output under WOT is confirmed by signal-massagers such as HKS VPC, Apexi S-AFC or LinkECU Intercept products being able to skew AFM signal and actually change AFR under WOT.

Also '82-83 cars don't have variable-position TPS; just on/off switches for idle and WOT positions. Thus AFM output is doubly important to measure load/air-volume for injector pulsewidth look-ups on map.

 

[Funkycheeze]

'Bolt-on kit'

Hahahahahahahahahahhahah

doesn't exist anymore.

 

[Atl_Racer]

'Bolt-on kit'

Hahahahahahahahahahhahah

doesn't exist anymore.

Yeah doesnt exist NEW

 

[dannoxyz]

Heh, heh... even if bolt-on kit exists, you don't want it. I've found kits for other cars to be extremely low quality and incomplete. For that amount of $$$, you'd get way better parts and quality by assembling your own pile of parts into a "kit".

For example, 2-yrs ago I turbocharged my wife's Scion xB and considered this kit:

Scion xB Turbo Kits | TurboKits.com

offering Scion xB Turbo Kits, Turbocharger Systems and Components to Boost Your Horsepower!

www.turbokits.com

Carefully looking at parts-list, I would immediately throw out 75% of that kit as unuseable. Ended up assembling much, much better kit for less than that. With water-cooled dual ball-bearing turbo no less...

 

[Flyin' Hawaiian]

Open-loop means it ignores O2-sensor. This occurs in bone-stock factory configuration too when you're at over 80% throttle or so. If you've got O2 meter or wideband hooked up, you'll see that that AFR dithering across 14.7:1 stops and mixtures goes rich.

At this point ECU still uses AFM signal to look up injector pulsewidth on map (rich mixture). However, once AFM maxes-out flapper-door, ECU still uses AFM signal, and lookup-point is pushed to edge of map. Meaning extra air-flow above stock cannot be measured by AFM. So if you've got boost on top of 1-atm, AFM can't tell ECU it's got more than WOT, so it just injects whatever fuel-value is stored at WOTxRPM on map. So resultant AFR will be lean because you've got more air than stock that ECU doesn't know about.

ECU still using AFM output under WOT is confirmed by signal-massagers such as HKS VPC, Apexi S-AFC or LinkECU Intercept products being able to skew AFM signal and actually change AFR under WOT.

Also '82-83 cars don't have variable-position TPS; just on/off switches for idle and WOT positions. Thus AFM output is doubly important to measure load/air-volume for injector pulsewidth look-ups on map.

Yes, this is mostly true from what I've found, but with a turbo pulling through the AFM, the metering door stops well before 80% throttle, its more like 20-30% throttle. Of course, this is also a variable depending on turbo size and trim wheel, as well as other things that we probably don't need to get into!


I believe it still reads the O2 sensor's data to change a/f, but is using that open-loop fuel map, which is just basically set on tps, O2, max airflow into engine and the water temp as an on/off switch for cold start fuel map. Why do I believe this? I found my wideband reporting very incorrect readings, even in open loop mode, when I had an O2 sensor go bad from a previous head gasket failure. Changed to new O2 sensor and a/f was back in range---or what I previously saw as "back in range". It definitely bounced around from 12 to 18 for a/f, but mainly stayed at 14.3-14.9 with steady throttle well above 4,000 rpm.

Of course, you've always sounded like you know this vehicle way better than I do, so I could very well be incorrect on it, but these were the things I found on my own vehicle when I was still running the 6m with a 60-trim CT26, iirc. Been many years since the old car was turbocharged!

Personally, I felt that while it was definitely possible to turbocharge the vehicle without a standalone ecu (and I also used an S-AFCii after a while without any other piggyback devices prior to it), the stock ecu was just not reliably controlling the engine safely and I ended up with several blown head gaskets from a/f rich/lean conditions.

Bottom line is this, just because you can, doesn't mean you should! LOL! If one wants a turbo, don't skimp. Do it right the first time or you'll be doing it over and over again until you do.

 

[Dat82supra]

Open-loop means it ignores O2-sensor. This occurs in bone-stock factory configuration too when you're at over 80% throttle or so. If you've got O2 meter or wideband hooked up

hey thank you man for the thorough explanation I needed to know what to really for for it because I’m rebuilding the motor right now from the top up and I’m going to be doing a full rebuild once I get more time too it really makes sense from what I’ve heard from other people and my tuner was saying almost the same exact thing but I do appreciate this thank you again!

 

[dannoxyz]

Bottom line is this, just because you can, doesn't mean you should! LOL! If one wants a turbo, don't skimp. Do it right the first time or you'll be doing it over and over again until you do.

Yes, there's a lot of variables and grey areas with factory ECUs. The '82-83 ECUs require WOT to go open-loop regardless of AFM output. Thus, O2 is still used for feedback until then. The later ones with variable-pot TPS will do it sooner.

You're right, only so much capability with factory box and takes A LOT of monkeying around to make it work. Nowadays, it's so much less effort to install aftermarket programmable EFI. Considering state of old crispy harness causing endless troubleshooting. Cheaper too compared to cost of repairing blown engines from non-optimal tuning!