code4

iTrader: (30)

I have been running a turbo set up on the street for a couple of years at around 11# of boost. (no track around here) I decided this year to up the boost, I replaced the tc 76 with the new tc 78. Put some slicks on & found some secluded roads.

Well I could not get to 15#'s so I replaced the MBC with one that I know is good. I finally got to about 16 on my guage but I have yet to hit 210 KPA on HP Tuners? It hits 205 which doesn't jive with my guage right? It makes some nice power but I am wanting more. LOL

My question is can I be out of turbo? I have a 347 with afr heads, a nice free flowing kit with open down pipe. Here is another piece of the puzzle, I am at around 3500 to 4000 feet in elevation.

All my pipes are nice & tight, I don't think I have any leaks.

DrTurbo

iTrader: (3)

Should be enough for 9's@140+mph. Josh from KYTP did that with a TC76 only...you should still have more.

code4

iTrader: (30)

Yes I have read everything about this turbo on this site. I'm just trying to figure my boost #'s.

I just did some runs tonight & really it stayed mostly around 195 KPA no matter how much I turned the MBC up. It also ran my injectors up to 80 to 83 % DC at 11.0 to 1 afr spraying meth. So I am probably pretty close to max on my fuel.

ls1408cp

iTrader: (37)

I was talking to the sponser about a t-80 I think its the biggest they make in that frame.

DrTurbo

iTrader: (3)

Dude careful......if that meth hiccups, that motor is toast.

DrTurbo

iTrader: (3)

You can't build a TC with an 80mm wheel. Not enough turbine to drive it. You can move up to the mid-frame, but its a much larger unit and much bigger.

engineermike

Boost controllers are limited by what the wastegate can or can't do. Wanna see the real limit of the turbo? Install a block-off plate before the wastegate and be prepared to replace head gaskets at minimum. I believe that turbo can make 20+ psi on your motor.

JZ 97 SS 1500

iTrader: (2)

Bingo.....wastegates are pressure regulated. Exceed the pressure and no more boost.....doesn't matter what turbo is under the hood. I don't recommend doing what Mike said....he's crazy.....turbo Jet Ski's are for the birds BTW....

code4

iTrader: (30)

I bought the WG from you guys, I think it was a 38mm Ultra? If I remember correctly. What can I get that will bolt in it's place? I don't have a lot of room for one that is physically much larger

JZ 97 SS 1500

iTrader: (2)

You don't need a bigger gate...just more spring tension. Have you stacked the springs that came with the gate. The Ultra's came with extra springs to stack up the tension on the valve.

code4

iTrader: (30)

It actually didn't, the instruction mentioned them but they weren't in the box.

Can I buy some from you ASAP, I am travelling to wa state to run this thing on a track this sat.

JZ 97 SS 1500

iTrader: (2)

I will check in the morning and have some sent to you. Send your info to Dr. Turbo on the board....he will take care of it. Address and contact info.

code4

iTrader: (30)

Thank you very much, I will pm him.

Johnv

What about the race cover, if you whant more - supposed to flow another 120 hp.

hellbents10

iTrader: (10)

We have done 19-20psi with a tc76 on the street with a 6l. 14psi on this vehicle was worth 654rwhp with a auto and 22" wheels. That one run at 19-20 killed the turbo though. Chris now keeps it below 15 with the new unit.

52172

iTrader: (2)

How did it kill the turbo? Did it overheat? Also about the WG would an EBC fix his boost problems and allow him to go to higher boost? Is he needing a heavier spring because he is running a MBC?

hellbents10

iTrader: (10)

Over spun.

ls1408cp

iTrader: (37)

so would a tc76 be able to make more power on a 5.3 or a smaller motor because of backpressure?

fenix999

iTrader: (17)

relatively speaking yes those tc76's and tc78's will make more power on "smaller" motors since they will be closer to their efficiency range with smaller cubes. They are rated to 1000+hp, you just have to use them correctly to achieve that goal. Basically a bigger motor will choke the **** out of that small T4 frame turbo, thats why guys are using bigger T6 units to "start off with" since they can house more appropriate and larger turbine/compressor wheels (like the 80mm and up units somebody requested several posts above me), downside the T6 units are alittle bigger overall, which kinda sucks but who cares - who needs a radiator or fans lol/jk

DrTurbo

iTrader: (3)

They work fine with the smaller motors. T4 units are not designed to be running on big cube motors. T6 is definitely the way to go if you have a big cube LSX based motor.