Bolt-on Boss bb turbo vs GT35R?

[sneakypete]

im running the Boss Series Comp turbo right now. The CT467 with DBB on the stock manifold, and using Maftpro controlling the boost. Im only boosting 15psi right now and its quite impressive. It pulls hard enough that i lose traction through 3rd gear. It time to invest in a set of coilovers and bigger wheels. I just finished breaking in my new motor so i havent really pushed it to the limit.
I plan on getting dynoed in march so i will post up the numbers when i get them.
Overall, this is my favorite turbo so far (had a stock CT and an SP61GT).
-pete

 

[supraman2008]

i like this topic i have my mk3 in houston right now doing a aem standalone. i upgraded from a stock 1jzgte to the following
- Precision Turbo
- Pt61
- 61mm Inducer 82mm exducer
- 74mm exhaust wheel
- Manic Tech T4 1jzgte single turbo manifold
- Tial 38mm external wastegate
- 3 in downpipe
- Front mount Intercooler

Blow Off valve
- Greddy type s

Fuel
- Precision Fuel Injectors
- 680cc
- Manic Tech Custom Duel Feed Fuel Rail
- -8an Duel feed Fuel Lines
- Aeromotive Fuel pressure regulator
- 90 gallon per hour denso fuel pump

Electronics
- Boost Controller
- HKS EVC

- Engine management
- Greddy Emanage Ultimate
- Greddy 5 bar map sensor

- Boost gauge
- Greddy electronic boost gauge

- Wideband
- Innovate LC1

Cam Gears
- AEM adjustable cam gears

Hardware
- ARP Headstuds
- Steel Braided Lines

Act 6 puck sprung hub

everything was find until the car was started and they never got the greddy to work so thats why i had to change to a different ecu im very curious to what numbers i will get on the dyno?? any one have this similar setup what numbers are possible with this??

 

[becauseican]

Most 61mm turbos use a GT35R compressor wheel, I am not sure if this is the case with the BOSS turbo' but I think the old SP61's used this wheel. I have a DBB Precision T61 on my car, and I measured it along with a true GT35R I had in the shop , and the compressors were exactly the same. The GT35R is on a 1jz that we are tuning right now, and it is a blast to drive, we will strap it to the dyno within the next week.

Brad, it basicly comes down to if you want to shell out the extra cash for a manifold, wastegate and new piping. If an engine swap is in the future, just get the BOSS bolt on and enjoy. You will have the turbo swapped and running in one afternoon.

 

[MRSUPRA]

The two main drawbacks of using the bolt-on turbos is the poor flowing stock exhaust manifold and use of an internal wastegate. If you ever want to go for more power those two items will cost you horsepower and boost control.

I went form a:
-CT-26 upgrade-Very fast spool, but no topend.
-SP61GT(bolt-on)-Not a stump-puller like the CT-26, but nice linear power with great topend. 451rwhp at 20.5psi stock motor
-SP59GT- (Full HKS manifold/extrernal wastegate) This turbo is still a 61MM but with a slightly bigger turbine wheel than the SP61GT- IT was a llittle too laggy for me. I'm sure the BIg manifold did not help. Made 511rwhp at 24psi on a stock motor.
-GT35R- Still using the HKS manifold, this turbo has nearly the same spoolup as the SP61GT on the stock manifold. On my fully built motor with 264's, it put down 431RWHP at 17psi on a mustang dyno that reads 15% lower than a dynojet. Can't wait to dyno again with race gas.

 

[Nick M]

Not exactly sure why you'd want to push 850hp using a stock exhaust manifold... If you're spending that kind of money (supporting mods), just get a tubular manifold...

So when you open the hood and they see the semi log manifold, they think you have nothing.

 

[IJ.]

Don't open the hood and tell everyone it's stock

 

[shaeff]

So when you open the hood and they see the semi log manifold, they think you have nothing.

Touché. :icon_razz

 

[Insidious Surmiser]

I do make a T4 turbo with an AR of .81. I make it with a 3 1/2" v band on the exhaust side, now this one will make more power than the stock set up.

now you have my attention :naughty:

 

[thedave925]

Bright shiney things on top keep a casual observer distracted

And if you know something, you may ask why is there a 4" filter on there?

And i want to thank Adjuster for the idea to move the PS reservoir where it is Took some a lil modding of the oem bracket, and a custom 90* bracket with 2 holes in it, mounting to the old air box screw mount


Thats a bolt on t70.

 

[Nick M]

Don't open the hood and tell everyone it's stock

A sure way to let them know you are not being straight about what you have.

 

[IJ.]

Or you can be antisocial like me and not go anywhere where you'll be in the position to be asked to open it

 

[Insidious Surmiser]

haha... good idea

 

[SupraOfDoom]

I'm surprised I only see 4xxRWHP dynos for you GT35R cats. There are plenty of 4 cyl dsms, evos, and wrx's making a lot more power then that with the GT35R.

 

[Nick M]

I'm surprised I only see 4xxRWHP dynos for you GT35R cats. There are plenty of 4 cyl dsms, evos, and wrx's making a lot more power then that with the GT35R.

With a significantly different power curve. And not in their favor.

 

[Justin727]

With a significantly different power curve. And not in their favor.

This is true. I know someone that has a Gt35R on his GST and it comes on right before he shifts. Doesn't have much useable low end at all. Hell the 1st 4 gears have nothing it seemed like.

 

[MRSUPRA]

I'm right around 495rwhp with my GT35R using only 93 octane so far. I don't see any reason I cannot easily hit 600+rwhp on race gas once I get the new fuel system installed. Wait til I redyno..

 

[kikdurazz]

So does anyone have any real world dyno results for the Boss 61's? Aside from it pulls hard and way faster then my ct?

I'm at a cross roads right now deciding whether to go GT35R and dumping the Lex/AFM and going MAFT pro as well.

Or going 61mm Boss keeping the Lex/AFM and saving some funds.

Would like a nice 450+ RWHP to satisfy the right foot.

 

[jtamulis]

um, the JT61GT (www.NotRice.com) _IS_ a GT35R (non ball bearing, or more for BB)

With a BOSS bolt on housing.

Jeff

 

[Nick M]

Non ball bearing makes it a GT35 and not a GT35R, in Garrett nomenclature, correct?

 

[tekdeus]

So does anyone have any real world dyno results for the Boss 61's? Aside from it pulls hard and way faster then my ct?

I'm at a cross roads right now deciding whether to go GT35R and dumping the Lex/AFM and going MAFT pro as well.

Or going 61mm Boss keeping the Lex/AFM and saving some funds.

Would like a nice 450+ RWHP to satisfy the right foot.

I just finished a custom GT35r install. The amount of time and labour and cost was dramatically more than a bolt-on would have been. I really see the merit of these boss kits now!! I posted a lot of pics and you can see how much trouble it was at the end of this thread: http://www.supramania.com/forums/showthread.php?t=86561

My setup should have faster spool and more top end than a bolt-on, but it would be nice to compare to a Boss or JT turbo dyno to see just how much the difference is, and if it is worth it!