Gabbiani

iTrader: (20)

Trying to figure out where to go next.
-5.3 with Weisco pistons
-Gen 4 rods/crank
-TFS 220s
-BTR Turbo 3 cam
-E85
-On3 7875 with 3 inch ebay air to air
-Vette t56
-built 8.8 in the rear, good drive shafts, 3.08 gears
-QA1 Coilovers front 550# springs
-Caltracs, Beltech 3" leafs, additional 2" block rear - beltech shocks
-25" ET streets on rear and street tires up front for now
-C5 brakes all around
-2step @ 4500 so far leaving on @ 10psi.
-3200lbs without me


Made 770 all wheel horse power on a dynojet at 19psi. Have run higher at the track but doesn't really pick up mph. The turbo and cam don't match.

Best ET 10.60 @ 136mph 1.71 60' with 3500DA (60 gets better every outing but mph always 135-139)

Stick shift truck with 99% street time. Spool time matters. Big frame t6 stuff will not fit. Not sure if a t4 BW would.

Been itching to upgrade the turbo but am really limited on space. I always end up back at the pt7675 ball bearing being the best (and most expensive) option. That might get me another 100 hp.

No particular goals. Want more power. Don't think a 9.99 is going to happen but a few more tenths and another 10 mph would be awesome.

So what do I do? Real turbo? Plate kit and just spray it? Auto would be far faster... but its the only running manual awd ls I know of.

Thanks

svslow

You have the trap speed to go 9.99, if you can make it leave hard enough.

Gabbiani

iTrader: (20)

Thanks - Some of the 6 speed guys make it look so easy.

JoeNova

There are small frame 84 and 88mm turbos available from On3.
The billet 84mm is a drop-in replacement for the 7875. I don't think you'll have to change anything.
The 88mm uses slightly different housings. Large dischargers on both compressor and turbine.

Neither are as big as an S400 series Borg.

Gabbiani

iTrader: (20)

But they all have the same turbine don't they? I haven't measured but backpressure has to be insane.

coltboostin

Very cool. Have a build thread? What T case?

Ping King

iTrader: (20)

I'm interested to hear what you're doing for a transfer case and or how it was connected to the trans.

Gabbiani

iTrader: (20)

No build thread. Should have done one.

It's a bw4472. Trans is vette t56 with front cover swapped.
Adapter was cut on waterjet and mill.

JoeNova

The billet 84mm has the exact same turbine housing as the 78mm.

I'm not sure on the 88mm. Just because they are the same A/R does not mean the turbine housings are the same size.

If backpressure is high, than your setup is likely being limited by the positive overlap camshaft.

Gabbiani

iTrader: (20)

No argument on the cam...
The 88 on3 looks like an 83 exhaust wheel. Need to look more into it and dimensions. Could be a cheap upgrade option. But the only data I can find on it is a dyno graph that peaks at 5200rpm. They claim to have people going 150mph on it.

fst100

iTrader: (5)

I don't see where you have any suspension mods listed or whats your suspension setup like? if its near stock, might as well start modding the suspension so all the power can go to the ground and get that 9.99 slip

Gabbiani

iTrader: (20)

Updated first post. Its a basic caltrac setup.

SLOW SEDAN

iTrader: (13)

i was able to get it to a 9.5 @145 at over 4000lbs. Not a bad turbo for the price, should roll out nicely at your weight.

yenkomike

iTrader: (2)

the 88/83 . the turbine is measured at the exducer so it is a good amount bigger than your 78/75.as far as size it is bigger on the exaust side than yours but not as big as a borg 400 series turbo. but it is a slower spooling turbo than yours for sure.

you are at a hard decision as more topend might help but if it gets laggy out of the hole you will never get the et back you loose once it spools. keep working on that launch my friends Camaro has ran 9.44 @141 with a cast on3 78/75 with a 5.3 at 3550 lbs. triple 12 cam. good luck.

oscs

iTrader: (19)

I bet that thing is a blast to drive

ddnspider

iTrader: (26)

That sixty foot is weak for that power level and what is a reasonably light truck. You need a real tire(4 that is lol) and a 2 step. That thing should 1.4 sixty. 3 tenths in the 60 would get you pretty close to a 9.99.

SLOW SEDAN

iTrader: (13)

Is it bogging off the line with AWD and 3.07 gear? I missed what clutch your running.

slowride

iTrader: (3)

On3 or VS needs to graft that billet 84mm wheel to the 83mm turbine and housing lol

neverstop

that is an epic build.

i wonder what the lower IATs from a M15 alky control kit would get you? I bet that cheap intercooler is costing you at least 50whp. I bet a velocity stack on the front of the turbo and no filter at track maybe worth some?


I don't know about the other turbos or if stock rods would take it, but a 100 shot would get you that 9 second pass pretty easy I'd bet and be super cheap.

Nitroused383

iTrader: (10)

Smaller cam and 3.5-3.7 gear and she will run so much harder even with your same turbo.