Karpellarpy

iTrader: (3)

I've heard that the Turbonetics TC76's are working well for the rear mount fbody guys, but I haven't been able to find any good examples around here. So post up your TC76 rear mount results!

omore001

iTrader: (1)

I don't have results but I have some information you might benefit from, check out http://www.exoticperformanceplus.com...Car.php?car=32 They have a similar set-up to yours and mine.

Karpellarpy

iTrader: (3)

Yeah, I've read through that build several times. I heard that the 408/76gts setup had spool problems and was laggy, but it's running slp longtubes and I heard that it had several exhaust leaks. I'd be interested to know how it is with those issues addressed. Plus, dyno results with the 408 and 76gts aren't posted. I've been told that the tc76 will outspool the 76gts, but will not quite make the same power, but I haven't been able to find any examples.

DrTurbo

iTrader: (3)

Yes the TC76 will spool like no other out there. Almost like a roots blower....lol. They will make big power on a rear mount and will easily get you into trouble with the ditches...lol

180ls1

iTrader: (4)

is that due to the a/r or the veins or a quickspool valve or what? Sorry i dont know a whole lot i am just trying to learn.

tahoeryan

iTrader: (2)

I'll let you know as soon as I get her back from the shop

Ryan

Karpellarpy

iTrader: (3)

Yeah, definitely let me know how it turns out. Back when your car was a 346/gt67 combo, it produced much better numbers than mine did, but I never turned the boost up over 8psi due to stock high-mileage longblock.
Dr. Turbo, what are the limits of the tc76 ... hp wise, boost wise, etc? What is the 'big power' levels that you are suggesting? I still can't find any examples of a rear mount using the tc76.

extremetoy

iTrader: (17)

i have an s10 with a tc 76 on a 6.0l it ran a best of 11.5 at 125 at 10psi it made 600 hp/tq


now im moving it to a front mount with a 5.3l

2ktransam

iTrader: (12)

My truck is a pig at 5200lbs but I have ran a best of 11.81@112 so far at 11psi. My setup is a stock 6.0L, STS with TC76 BB and a z06 cam. I have tuned it for 14psi but I haven't ran it at the track on that setting yet.

2nd Gen Fl 'bird

iTrader: (13)

ever heard a converter scream for mercy?You say stock, meaning just zo6 cam? That's laying down torque my friends.

2ktransam

iTrader: (12)

The 6.0L is a stock lq4 out of a work van that has nothing done but a z06 cam and springs. Everything else on the motor is just the way it came from the factory. I don't know how long it will last with high boost but it has done good so far with the meth. It has 70+ dyno pulls, 10 track passes and 100's of street pulls at 11-14psi and no hickups yet. I watch my tune religously and keep the AF in the low 11's and it just keeps on running. The converter deffinitely hates the turbo. I switched to the TC76 and gained .8 seconds at the track but lost 55rwhp on the dyno due to blowing through the converter.LOL

hellbents10

iTrader: (10)

5800lbs 11.01@127 FMT though, they are capable of 900fwhp.

longrange4u

iTrader: (2)

Uhhh... well I am running a 408 with a PT88 (supposedly a much slower spooling turbo) and I have almost no delay in spooling. It is sick fast and spools great! I can only imagine that a TC76 would spool instantly... and may even be choked on a 408 setup.

Karpellarpy

iTrader: (3)

yeah, I'm a bit worried about it being choked on my setup. With exhaust leaks, my tiny gt67 behind the 402 would spike to 12 psi, then fall to 9psi on the dyno and made 575-600rwhp depending on how hot the turbo was. On the street (and with the exhaust leaks fixed), it hits about 7psi, then the whole car starts shuddering and all power is lost and I back out of it. It will pull cleanly though at 6psi. I've been told it's valve float from high backpressure. I'm looking for around 700rwhp with awesome spool without having to rework the entire turbo kit.

longrange4u

iTrader: (2)

Yea beware of back pressure... it sounds like you are a heavy victim of that. Your boost levels seem low but I wouldnt think that is valve float (you see that at high rpm)... I think its more likely backpressure

DrTurbo

iTrader: (3)

. That TC unit is working hard on that setup....lol

hellbents10

iTrader: (10)

The 78 with the 1.15 housing you guys set us up with is doing much better though. We were running out of fuel at 19-20psi with the tc76 and a .96, now were are running out at 17psi with the 78/1.15 combo. The turbo lights up like yesterday on the 370 lol. The BB unit seems to be more stable when punished on this setup.

2ktransam

iTrader: (12)

I would deffinitely go with the tc78 and a bigger housing for a 402.

Karpellarpy

iTrader: (3)

yeah, the boost level is low because if I try and turn it up at all I get into this 'car shuddering and not making any power' situation. I was told that it's valve float *due* to the high backpressure. I measured my backpressure when it wasn't shuddering and saw ~30psi at around 9psi I believe. I need to measure it again. It seems to be ambient temperature dependent as well ... some days it can pull cleanly at 8-9 psi ... other days, I have to turn it down to 6-7psi. The car is purely a street car, it only sees the track about once a year, so low-end grunt and quick spool are priorities. The TC76 sounds like a decent fit, but I don't want to spend all the money on it, then find out that it's still too small and/or wont make much more than what I'm already making now. I've seen where the 76gts has made 740+ on a 346, but haven't seen 402 or 408/76gts results. Also, I don't know if we can really compare front mount hp numbers/spool characteristics to rear mount setups, but thanks for posting the results anyway, I appreciate it.

2ktransam

iTrader: (12)

With my .96 housing I see 6psi by 3800 and my high setting hits around 4,200-4,400 in second gear. Third gear spools the turbo instantly. I would think that the 76 might be a little small for a 402 but it would boost instantly and you could always swap to the 78 wheel if you decide that you want more.