JalopySiR

Hey guys, haven't posted here in a while, but since this is the best site for turbo info on the net... This'ns not Honda related please forgive me. I don't own a honda anymore, but 4 cars in my family are force inducted.
Anyway, this question pertains to upgrading the turbo on a 91 Toyota Supra. MA70. It has the 7M-GTE engine. This would be a 3.0, 8.5 c.r. , 24 valves, DOHC, inline 6. it makes ~220HP/~250TQ on about 8psi off a CT26 turbo. I have 2 options that I can think off, bolt on wise, that I can think of so far. I do not want to go with a T88 kit, or convert to a T4 setup. I have the option to go with a
T3/60-1 "style" turbo or a Greddy (TD06SH-20G-14?cm2)) upgrade kit. I am leaning toward the T3/60-1, hi-fi. Does anyone know how this would work out? I am unsure of the a/r of the turbine housing, it is a Turbonetics stamping of the CT26 housing that will fit T3 turbine wheels. I have the option for either a stage 3 or 5 turbine wheel, I am leaning toward the 5. Compressor surge concerns under a certain PSI? Could anyone help me out? Have experience? Suggestions? Any help would be Greatly appreciated. Thank you for your time.

JalopySiR

c'mon now...

DigitalFusion

i a definately not educated enough only not only turbo sizing, but also yotas to be very helpful.

That said, have u tried looking up compressor maps to see which turbo would be best for you? BlueShadow has a great article (archived) on reading them, and the follow-up posts all help to figure out how to fill in ur data and links to where u can find the maps

DigitalFusion

https://honda-tech.com/zerothread?id=142398

JalopySiR

Ahhh, excellent. I actually found a compressor map for the TD06 as well... Thank you.

DigitalFusion

happy i could be of assistance!

lazerus

i have maps of most Mitsu wheels..

For the 7m, if you definately are set on upgrading the turbo off the bat....

Go with some nice upgraded injectors, im not sure how well the 7m ecu handles injectors, but i would imagine that 550's with a hks VPC/AFC Combo would work really well. (Convert to speed density) I would probably recommend replacing the headbolts with ARP headstuds, and an aftermarket headgasket.

Also another good idea (but not as good as a VPC IMO) for fuel setup is using a lexus/toyota V-8 MAF along with an SAFC and 550cc/min injectors, i've heard this works pretty well to get rid of stock fuel cut at 12 psi, and raise it up a good bit. (obviously depending on turbo/engine airflow)

of course then the usual stuff, intercooler hardpiping BOV 3" exhaust...

Also, i would definately recommend visiting, and e-mailing members of http://7mpower.com for good ideas, i know there are quite a few little things with the 7m that need to be addressed with greatly increased power levels over stock. Also, visit http://www.supraforums.com in the MK3 section! http://www.suprastore.com http://www.i-supra.com .... lots of web sites for some reading.

And for a turbocharger, i would recommend talking with http://Full-race.com & Precision turbo http://www.precisionturbo.net/ (Arturbo on honda-tech)

Good luck with your projects.

JalopySiR

Lazerus,

Thanks for all the extra info. My brother already has a very good general upgrade path mapped out. All of the items you mentioned are on it plus a few airflow/cooling related issues. Hopefully someday this will be a beast of a car. Right now I am trying to select which turbo will best suit our power needs(Bolt-on affair with most HP potential) It turns out they are probably going to be very similar... It'll probably come down to whichever one we can get a better deal on... Thanks for the links!

rOby

i have a little bit of experience w/. the 7m, enuff to say i dont like it. swapped to a 1jz ...behold glory:p. the fall of the 7m is its head design as well as never ending blown gaskets.i believe the 2.5liters? is too much for a 60-1...the motor will just exhaust it to quickly. at the supra dyno day in houston, a mk2 supra w/ 7mgte put out 400whp w/ a 60-1...it was on 28psi though. that turbo on that car was exhausted. id suggest at least a 62-1 or something like , even thought thats what, 20 more hp than the 60-1. if you really want to stay w/in the t3 family, your best bet is a precision sc61 w/ t3 housing and a .82ar. that will give you lots of room. contact arturbo for pricing. if ur wondering whatever happened to the 7m, it had 2 spun rod bearings and a whole lot of detonation craters on the #4 piston.. 1jz.2jzwoo woo

JalopySiR

Hrmmm, the blown headgaskets, once properly addressed, are not a problem. As for the turbo, I am looking for a bolt on unit, and the new "bolt-on" exhaust housing fits T3 wheels. As for the compressor size, I am limited by space. Which is the reason for the 60-1 "Hi-Fi" (60-1 wheel in a T04E housing). You're not confusing a 60 trim, with a 60-1 are you? I would think a 60-1 with a stage 5 turbine would be worth more than 400HP@28PSI.....

lazerus

IT definately should be, especially on the 3 litre 7m. Def. go with a stage 5 wheel if you are using a T-3 housing.

JalopySiR

Thanks for the replies guys. I love this forum. I love turbos.

rOby

nah im not confusing it. the hifi is smaller overall than the 60-1. i dont like the 60-1 pushed to its limits. ive seen hks gaskets blow on the 7m, these were 2mm gaskets!!!if u need some help im me, i will get u in contact w/ my friend, he had a 7m and now the 1jz...he knows his **** left and right , up and down. try http://www.thermactor.com

JalopySiR

I've seen numerous 7MGs putting out around 350hp/400tq, on smaller turbos with less PSI... Also, the thicker the headgasket, the lower the static compression(not good) and thick headgaskets (2mm) give cylinder pressure more surface area to push out on. You want the thinnest stopper gasket available. You also want to torque it down much more than the factory rating of ~50'-#. You want around ~70-75'-#.... There are also numerous cooling issues that also contribute to BHG syndrome. Regardless, we will not be swapping motors. If it has some sort of catastrophic failure, it will just be rebuilt, beefed up. At least in the U.S., I feel the 7MG has MUCH more potential than a 1JZ. This is my opinion of course. There is no replacement for displacement.

rOby

LOL, your definatley wrong on that last statement, ill let it rest on that.

JalopySiR

Thanks for your input. I appreciate the replies.

lazerus

the only real thing i'd be worried about is making soup out of the oil pump, and of course blowing the head gasket.

ARP's and a cometec metal headgasket coppersprayed with decked block and milled head should be plenty good for 500+ whp (as far as headgasket is concerned)

I will agree that a larger headgasket is not the proper way to lower compression ratio.

Brad

JalopySiR

Yeah, the headgasket is of course the biggest concern. As soon as we scrape together the cash, it will get done. After that, there are people on 7Mpower.com making 500+whp on stock blocks. That is craziness.

Fac3Man

As I remember there is a proper torquing sequence for the head bolts that are not covered inthe manual for the 7m, someting about using the jdm specs?? Am i correct?

Phoenix GSR

I have a supra as well and have been through several different setups.. I personally dont like the greddy/mitsu setup...

if you want the most power for a bolt on app., turbonetics makes a t3/t4 that bolts on.. on the supra forums it is sold as "the suprasport turbo", but I bought mine directly through turbonetics for less... I have tried 2 of those... they are the best bolt on affair (they still require some modding), but in my personal opinion - for close to the same price you can but a log manifold, or a manifold adapter of you prefer and buy a regular t3/t4 from someplace inexpensive like http://www.cheapturbos.com .. I would do that, or if you want more power as someone mentioned above use the precision sc61 witha log manifold or adapter.. it will fit, especially if you use the smaller housing option on the cold side... the turbo is a few hundred more, but it has proven to be worth it...

if you want to go cheap, I have tried several modded ct26's, from the v trim to the 60-1... I think these offer the best bang for the buck without question, but you will be limited on the hp limits...

hit me up if you have any other questions

JalopySiR

The SupraSport turbo is the unit I am speaking of. I would be getting the stage 5 wheel, and the 60-1 Hi-Fi compressor. I was also thinking about the MaxxAuto T4 adapter, but I want to keep it as "bolt-on" as possible, while encompassing a larger turbine housing (not a stock CT-26). I really don't feel like having a custom DP made. What exactly didn't you like about the Greddy setup? Also, what has to be modded with the suprasport turbo?

Phoenix GSR

my buddy still has the supra sport 60-1, stg 5... it is a good turbo, made 415whp @ like 18psi... everything that goes to the turbo needs to be moddified, except the manifold.. it uses a standard garret center section and cold side, so the oil feed and drain need to be modded to work, same with the water lines, and the intake (the acordian pipe if you are still mostly stock) will not fit of course...

if you are looking for 450 or less whp I would stick witht he ct26/60-1 with a clipped hotside.. it will make over 400 at the wheels at reasonable boost levels, it is really cheap, and it is truly a bolt on... if you are looking for more power than that I would really start looking into a standard size turbo with a new manifold - it wouldnt hurt to have a decent wastegate with that much power... it is certainly not 1 bit harder to install (especially if you are doing the adapter) than that suprasport turbo, and the turbo is cheaper.. and you will have a bigger market to sell it to when you are done!

I have one in my garage (ct26/60-1 /w 10 deg clip) I need to have rebuilt, then I will put it up for sale... or maybee I will put it on my teg... havent decided!

Phoenix GSR

my dislike of the small greddy kit is just that it doesnt seem to make much power.. if you were to get the jdm t78 or t88 kit I would be all for it, but the small greddy doesnt seem worth it..

also rebuilding the mitsu turbo may be more expensive than a garrett unit.. I am not sure on this

JalopySiR

Hrmmmm, good info. I REALLY don't want to have a custom downpipe done... so maybe I'll look into some kind of Greddy T78/88 or a Sound Performance T4 setup. As long as the whole shebazzle bolts up... Looking for between 400-500hp at the wheels...