[Patrick94TT]

Finally after three years of owning my Supra and staying BPU, I've got the time (and money) to build the head and go single, with all the fixings. A little background:

Original '94 TT - 82k miles
Built BL auto w/ 3800 stall
New TT head w/ HKS 264 cams, BC springs/retainers, and new valves/valve seals
AEM EMS

I'm having a hard time choosing a turbo, strictly because I don't have much experience with single turbos. I've decided I don't want a 61 or 67mm turbo. I recently sold another Supra I owned that was equipped with a PTE 61mm turbo. It was fun, but the power dies out and I'm not really a fan of that. My goal is around 800hp on race gas, and 500+hp on the street. I RARELY drive my Supra (put about 10k miles on her in my ownership) and I'm looking for a good powerband on the freeway, not on city streets.

From research I've done on the forums, I've narrowed down my options to the PTE71GTS or GTQ series, or bigger. I was just looking for some good information from anybody who knows the turbo first-hand, and can give me advice on what size to order (a/r, compressor hs. etc.).

I've also considered a GT42 series turbo, but I've heard bad things about that particular turbo on autos. Can anyone give me more information about this?

Also, where should I order my turbo from? I already have the T4 turbo manifold, so when I place my order, it's just gonna be for the turbo. The Garrett and Precision websites are hard to navigate.

Lastly, what am I going to have to upgrade to run full boost on either of these turbos? My plans right now are to run either turbo on a T4 manifold w/ 4" all the way back to hook up to my HKS Ti. I'm also upgrading the fuel system to 1000cc and installing an HKS DLI to keep the ignition in order. Am I going to need to upgrade the intake manifold too?

Thanks for your help guys.

- Patrick

 

[BJF]

i wouldnt worry about doing head work or intake mani. i would go with some 272's and a gt4202 or a 74gts both are 74mm turbos and even with that you will need some really good tuning. remember you are auto so your numbers will be a little lower than if you were six speed. 800 on a six speed is probably like mid sevens in an auto. good luck

 

[LLCoolJ94]

I would say 74GTS or 76GTS are your friend.

No you don't need an intake mani, but it certainly won't hurt

You definitely should look into getting 272's as mentioned above to allow the head to breathe and let the full fury of the turbo out. Otherwise, you are robbing yourself of power.

Tuning will be a major issue for you. Look to spend 1k for a quality tune. Don't forget to invest in a boost gauge, oil pressure gauge, and wideband if you have not already done so.

If you have any other questions, feel free to PM me and I will help you out the best I can.

Joe

 

[Craig Bush]

many here on SF's consider a 71 or 72mm ideal for a street turbo (particularly when top end is a little more important than early responsiveness without being completely one dimensional).

the borg warner turbos tend to make a little more power than equivalent garretts, so a gt4294 ( 71mm compressor inducer) is rated to approx 850 fwhp (iirc) whereas the BW s300 91/79 (66mm comp ind, also called an s366) is rated from 550-830 rwhp - so might be exactly what you're looking for. some have questioned the BW durability vs garret, particularly under extreme conditions, but i don't think it's definitive.

the gt4202 (74mm comp ind, 700-1000fwhp) is probably a little bigger than you want, but same neighborhood anyway).

keep in mind, supporting mods are required, including full fuel system (two walbros/stock or hks denso pumps and 1000cc inj's should support approx 900whp). you'll also need a built auto. and if you decide to push past 800 or so whp, most would recommend building the bottom end. oh, an LSD wouldn't hurt either (TRD is probably most common).

hope this is what you're looking for!
craig

 

[LLCoolJ94]

I think the size depends on the owner. I like my 74GTS just fine. I wouldn't mind trying a 72 or a 76 to see how the shoe fits.

I don't trust the reliability of the BW series yet. My understanding of the HP differences are due to the construction of both turbos being different. But I won't claim to be an expert with BW.

 

[mcwop23]

I have a Turbonetics GTK-850 I'm not going to use anymore, it's a 72mm with great spool characteristics. http://www.racetep.com/tnetgtk.html has the specs.

 

[BlueSteel]

Out of all the turbos i've tried I still think my 74mm with a .81 a/r hotside was the most fun for the street. Decent spool with a hard hit once full boost hit. I miss that turbo

 

[foreverpsycotic]

S372 w/ a 1.10 AR

 

[Driftracer3]

There are a lot of choices to pick from. You could go with 71-76mm Precision turbos, all will make the power you want, but the 71mm will spool the best on the street. The larger the turbo the more power you can make obviously, but they will also make more power safely on pump.

I think the 76 might be a little big if its a street car, so I recommend the 71, 72, or 74mm, .81 housing, and an H compressor cover.

 

[CodyK]

There are a lot of choices to pick from. You could go with 71-76mm Precision turbos, all will make the power you want, but the 71mm will spool the best on the street. The larger the turbo the more power you can make obviously, but they will also make more power safely on pump.

I think the 76 might be a little big if its a street car, so I recommend the 71, 72, or 74mm, .81 housing, and an H compressor cover.

I'd go with the 74 it's going to be tough to hit 800 on a 71 through the auto. That's if you just have to have that 800rwhp dyno sheet.

 

[TurboPK]

look into the billet turbos, maybe a 74mm, or 76mm, and some spray!

 

[Patrick94TT]

Thanks for all your responses guys! After reading all the feedback, I've decided to go with a Precision turbo, and I'm leaning more towards the 74mm. My last question is, where should I order the kit from?

 

[CodyK]

Thanks for all your responses guys! After reading all the feedback, I've decided to go with a Precision turbo, and I'm leaning more towards the 74mm. My last question is, where should I order the kit from?

Wherever it's the cheapest haha. But seriously you said you don't need anything but the turbo right? Check out any of the forum sponsors man.

 

[Patrick94TT]

Wherever it's the cheapest haha. But seriously you said you don't need anything but the turbo right? Check out any of the forum sponsors man.

Originally I was going to use a T4 manifold I have sitting in my garage, but I decided to include it in the 61mm turbo kit I'm selling, so I'm gonna just buy a whole kit now. I was looking on MVP and didn't really see anything, and then I visited Boost Logic and saw a few kits. The one that really caught my eye was the stage 2 T74 kit I saw on BL, but it comes with a 44mm wastegate, whereas the other kits come with 50 or 60mm gates. The good thing about the Boost Logic kit is it comes with the 4" DP/MP, which will bolt up with my HKS Ti.

If I went with the T74 kit, what else am I looking at upgrading? I thought I read on their website that a built block and aftermarket intake mani were necessary to run full power on that turbo. Would I be okay with the stock intake mani, 1000cc fuel system, and a built street head? And should I ditch the 264 cams and go with the 272s? Basically, if I ordered the kit today and installed it next week, my setup would be:

'94 TT - 82k miles
BL built tranny - 3800 stall
AEM EMS and HKS DLI
AEM wideband
Complete 1000cc fuel system
T74 kit w/ 4" turbo-back piping
New head w/ HKS 264 (272?) cams, BC springs/retainers, new valves/valve seals.

Would I be okay on this setup or am I going to run into issues somewhere?

 

[Craig Bush]

... if you decide to push past 800 or so whp, most would recommend building the bottom end.

reprinted with permission.
craig

 

[Patrick94TT]

^^ Thanks Craig. Missed that the first time through.

As far as the block goes, what am I gonna be looking to upgrade? To be honest, I've never thought I would have to tear into the block and this is the first time I've even considered the work. Am I looking at just a set of pistons and rods?

 

[Hurrakaine]

Get a GT40 (good for 700whp+). With your power goals, aka 800 on the track in order to accomplish that you will need a kind of a big turbo. On a auto, it will be pretty laggy, and now you will have to get a GM transmission to hold the power. With the BL one, you are basically rolling the dice.

 

[Patrick94TT]

^^ Funny that you just mentioned that about the BL tranny... I was lurking through another thread a couple minutes ago and saw a bunch of guys saying that their BL trannies didn't hold up when going above 800hp, yet the BL website says it's proven to hold up well into the low 9's?

 

[Hurrakaine]

^^ Funny that you just mentioned that about the BL tranny... I was lurking through another thread a couple minutes ago and saw a bunch of guys saying that their BL trannies didn't hold up when going above 800hp, yet the BL website says it's proven to hold up well into the low 9's?

Yeah if it happens with 3 out of 74 cars thats enough to be proven in their opinion.
Its marketing, and with the bigger stall that you have, you are going to put down less power on the dyno.
The general consensus seems to be closer to 600whp is the limit. Its not BL's fault, there is only so much they can do with the stock transmission. If you enjoy your car now, then you are going to hate what you are going to have in the end if you want an 800hp auto car. If you just enjoy going fast, and you don't mind using a GM tranny, or a Ford one, in the name of speed then you will be fine.

 

[Patrick94TT]

Awesome advice Hurrakaine, I really appreciate the post! Looks like I've got a little more research to do on an auto tranny. Damn, I thought the BL was gonna hold up fine.