1991 Toyota MR2 Turbo

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watkins
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Re: 1991 Toyota MR2 Turbo

Post by watkins »

If that car is anything like Saab turbo engines, youll want to get higher weight oil than that. A 40 weight, or maybe even a 50. Turbo cars run hot and need more than just a basic 5W-30.
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Re: 1991 Toyota MR2 Turbo

Post by permabanned »

Tinton wrote:The car actually seems to get slower from 6000-7000 though, as if the turbo can't flow air at that high an RPM, even with 20 psi. The car is very very fast from about 3500-6000 RPM though. That's about the same powerband as my Fieros but without the lowend torque, and with much more speed.
well ofcourse it is, your way outside the turbo efficiency range at 20 psi, and your overspinning the turbo and air coming out of it is choppy and way too hot, the intercooler cant cool it enough. i wrote a lecture about turbos and pressure vs flow and all that shit in the blowout thread, im not gonna retype in here, but read some of that stuff, it will make sense. basically, whoever the previous owner that cranked the boost to 20psi on that stock peashooter is a f**k retard. simple as that. by cranking the boost to 20psi on that stock ct26 or c26 or whatever it is, the previous owner extended the range of turbo efficiency a little bit but you are still out of turbo by 6 grand because the turbo cant flow enough air to keep up with the engine

stock turbos are made for driveability, not to make serious power. stock parts make stock power, pretty much as simple as it gets
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Re: 1991 Toyota MR2 Turbo

Post by noob5,000,000 »

Damn 20 psi on a stock turbo is insane! The HT-18 on the FC runs out of breath at 12. What's stock boost on an MR2?
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Re: 1991 Toyota MR2 Turbo

Post by Tinton »

noob5,000,000 wrote:Damn 20 psi on a stock turbo is insane! The HT-18 on the FC runs out of breath at 12. What's stock boost on an MR2?
12 psi stock. The guys on the MR2 forum seem to think the ct26 runs out of breath at about 15 psi unless you rebuild it to spin faster or something. This turbo has been rebuilt, but I don't know whether it was modified to probably flow 20 psi or the previous owner just cranked it up being noobish. The car has an aftermarket intercooler and its been cold out recently so it seems to build boost pretty well, it just gets slower past 6k. With a ct20b (93+ MR2's turbo) it could flow well all the way to 7000 RPMs. Or maybe a GT35r, but I'm not sure this engine could even spool it. It'd probably spool at 5k or 6k or something like that :lol:. I couldn't live with that, the car is pretty slow without boost and its hard dealing with the current boost lag that lasts to 3000 or 3500 RPM.

Watkins I didn't know that, thanks for telling me. But I think the 5w30 will work just fine. I have 0w30 in my '88 Fiero and it works pretty well (its NA though). Right now its the coldest time of year in Georgia, and for the most part the temperature doesn't really get above 60* F. I think that by the time I change the oil again in February or March it'll still be cold enough for the turbo to not get really hot. Then I'll switch over to Mobil 1 10w40. Right now the car's running Mobil 1 10w30.

I also downloaded a shop manual and it said that for the temperature range here in winter 5w30 is fine for the 3S-GTE. In hotter weather though it'll need 10w30 or 10w40. Summers here are brutal :evil:.
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Re: 1991 Toyota MR2 Turbo

Post by permabanned »

you can tear apart the turbo and swap out turbine and compressor wheels, but on a turbo that small its just a bandaid. your turbo was most likely just basic rebuilt.

you should look into an hta35r. gt35r spools retarded fast compared to oil cartridge turbos because of the ball bearings, and HTA spools even faster than a GT35r. or you could get a GT30 and spool it all day and be happy
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Re: 1991 Toyota MR2 Turbo

Post by Tinton »

permabanned wrote:you can tear apart the turbo and swap out turbine and compressor wheels, but on a turbo that small its just a bandaid. your turbo was most likely just basic rebuilt.

you should look into an hta35r. gt35r spools retarded fast compared to oil cartridge turbos because of the ball bearings, and HTA spools even faster than a GT35r. or you could get a GT30 and spool it all day and be happy
For my turbo being so small the ct20 used in later MR2's flows better and is actually smaller. :P

Anyways, I changed the oil today. The car is strange in that you don't have to jack it up to change the oil. I can get under the rear of the car to loosen the oil drainplug easily. Too bad that's where ease ends with the MR2's oil change.

The f*cking oil filter is right next to the turbo :x :evil:. I couldn't get a good enough hold with groves on and the turbo kept burning my knuckles when I tried to remove the filter without the gloves. I finally climbed on the car and sat on the trunk right on the edge of the engine bay and managed to push down enough on the filter to loosen it by hand. That is a retarded place to put the filter; I know on Fieros you have to jack the car up to reach the filter but at least its VERY easy to get off with no hand burning. With the Fiero you can also pre-fill the oil filter before you put it on. I think on the 3S-GTE in the MR2 the oil drains out of the filter every time you shut the car off, and there's no possible way to pre-fill the filter when you put it on without spilling all that oil everywhere.

That's the way everything's been so far with the MR2. Some things, many things, are pure genius. Then there's just things that make you go WTF.
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Re: 1991 Toyota MR2 Turbo

Post by Bawked »

Tinton the ct20b turbo still runs out of air b4 7k rpm. Its smaller, the only reason it flows better is because the ct26 turbo has bad restrictions on the exhaust turbine. Both are about the same really.... ct20b a tad better but mostly more reliable. Go for a bigger turbo if u want power.
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Re: 1991 Toyota MR2 Turbo

Post by permabanned »

about the oil filter, i love where it is on my car. front of the engine, open end facing up. dont need any drainback valve or anything, obviously easy to prefill, and i dont gotta listen to the lifters murdering themselves without oil for a few seconds on cold starts.
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Re: 1991 Toyota MR2 Turbo

Post by Tinton »

permabanned wrote:about the oil filter, i love where it is on my car. front of the engine, open end facing up. dont need any drainback valve or anything, obviously easy to prefill, and i dont gotta listen to the lifters murdering themselves without oil for a few seconds on cold starts.
Exactly.

That's where the filters are on the V6's in my Fieros. Front-bottom of the engine, open end facing up. And without a cat there's a huge open space there to put your arm, so its easy to get the filter on/off by hand. With the cat there and working (back when my Fieros had working catalytic converters) it was tricky because there was less space and because the catalytic converter would always get hot in driving and stay hot. But even then that was easier than the MR2, I barely ran it (in cold weather even) to move it into the garage and the turbo got pretty hot. Its right there to burn your knuckles :evil:, dodging the cat on the Fiero wasn't that bad as long as you paid attention to where you put your arm and how much you moved it when you took the filter off. With the MR2 just gripping the filter burns the f*ck out of your hand because the turbo's right there.
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Re: 1991 Toyota MR2 Turbo

Post by permabanned »

Bawked wrote:Tinton the ct20b turbo still runs out of air b4 7k rpm. Its smaller, the only reason it flows better is because the ct26 turbo has bad restrictions on the exhaust turbine. Both are about the same really.... ct20b a tad better but mostly more reliable. Go for a bigger turbo if u want power.
turbine doesnt make the turbo flow better, its all in the compressor. turbine is just there to make it spool. obviously you cant take a T66 compressor and put a T3 turbine on it, the little t3 wont make enough torque on the shaft to get the big compressor spooled (this is where AR comes into play, the bigger the AR, the more torque the turbine can apply to the shaft, and the more exhaust volume and velocity it needs to spin up to the right rpms.

id highly recomment buying and reading maximum boost by corky bell. i havent read it but everyone is always recommending it. i might have to go pick it up sometime soon.

shit, this is the best part about being broke, you get plenty of time to do your research before you start buying parts
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Re: 1991 Toyota MR2 Turbo

Post by noob5,000,000 »

permabanned wrote: shit, this is the best part about being broke, you get plenty of time to do your research before you start buying parts
QFT :lol:
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Re: 1991 Toyota MR2 Turbo

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it always cracks me up when some noob shows up and goes like i bought all these parts and i have no idea what to do with them or why they dont bolt togeter. that really turns up the douchebag knob and i have to restrain myself from posting shit that would get me banned.

case in point, some noob on probetalk paid 1300 dollars for a set of custom pistons that were stock bore. has a stupider person ever walked the earth? i could have a complete built 600hp ready bottom end for that much, pistons, rods, rings, bearings and machine work for 1300.
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Re: 1991 Toyota MR2 Turbo

Post by Leedeth »

The people with money have no idea what to do with it.

The people without money know what to do with money but just don't have the money to do it.
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Re: 1991 Toyota MR2 Turbo

Post by noob5,000,000 »

Leedeth wrote:The people with money have no idea what to do with it.

The people without money know what to do with money but just don't have the money to do it.
Sad but true.
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Re: 1991 Toyota MR2 Turbo

Post by 94Corolla5Speed »

Leedeth wrote:The people with money have no idea what to do with it. Give it to the poor

The people without money know what to do with money but just don't have the money to do it. Use that money to make awesome shit EPIC f**k WORLDWIDE WIN. I'VE JUST SOLVED WORLD POVERTY
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