Dennis5374

Just curious as to how much hp the stoc 5.3 block and crank can handle? I'm intending on buying a brand new block, brand new crank and running forged rods and pistons, arp rod bolts, arp head studs, ls1 heads, and a pair of 7868 turbonetics t4 Benita's . I'm hoping to be in 4 digit territory and have it live. Has anybody been in this territory on a stock 5.3 block and stock 5.3 crank? What are things that are absolute musts to upgrade if so ?

JoeNova

I'm starting to think that you say Benita every time you post lol.

Throw rods and pistons in it, turn up the boost.

Dennis5374

Yeah , most people relative to the subject know that the turbonetics 7868 is nicknamed "Benita", I have a perfectly good running 6.0 but I think I can build the above mentioned motor for much less , have thicker cylinder walls, and hopefully withstand everything I can throw at it. Hopefully the ls1 doesn't grenade Wednesday morning as I intend on pushing it pretty hard on the dyno. While I'm on the subject , I've never ran water/meth before, what mix should I shoot for ? I'm using the hokey single nozzle kit and pump and spraying through Holley efi. Also joe who would I send my old 7868 too for a rebuild ? I've been recommended by a vendor to send it too turbonetics but I've called a half dozen times , and never gs through to anyone ...

Nitroused383

iTrader: (10)

Twin 78s will be a turd on a 5.3. Stock crank has reliability issues once over 1000 rwhp. I'm pretty sure twin 78s turned all the way up will max out a stock block too.

2000WS6TA

iTrader: (5)

i asked this question when i first started putting my set up together. you get a little bit of a mixed review, a lot of guys that are pushing over 1k hp have the money to invest in a forged crank and say the stock cranks start giving up around 1k. I have also been told that a lot of guys that use SBE and stock cranks have never known a stock crank to break, but when you're dropping that much money to make big power why take the risk?? i plan to turn my stock crank 370 up this week so will let you know if she lets go.

oscs

iTrader: (19)

What money? He's slapping rods in pistons in a 5.3 block.. hardly what I would call "big money"

oscs

iTrader: (19)

If you have the extra coin I'd throw a cheap K1 crank in it, I know a guy making 1500whp on one. With that said I haven't heard of a stock crank failing in a long time so it's up to you. With the stars aligning and perfect tune I've seen guys making 1300 on half filled aluminum blocks. Not sure about cast.

1CAMWNDR

iTrader: (21)

Stock crank will be fine. Those 78mm compressors are way too much though. Over 1000whp can be had with a pair of 60-66mm compressors on the right combo and be much more responsive on a 325" engine.

LS1NOVA

iTrader: (12)

I've been 7.90 172 with twin 7268 "TC" Turbonetics on a rod/piston 5.3 and stock crank. At 1200w the crank flexes and wipes out bearings but won't break. I'm currently swapping in a usa forged crank to try to go a little quicker. Yeah the 78 compressors are too big for the turbine but they'll make enough power to test your tuning skills.

oscs

iTrader: (19)

There it is

stoverz28

iTrader: (8)

Iron block?

ScottyBG

If you want to stick with the "Benitas" you may want to use a 6.0 factory block. It will spool them considerably faster. I think if your going brand new block the 5.3 and 6.0 will be about the same price. I also think the 6.0 iron block at stock displacement is quite strong, the wall thickness is still about 0.220 I understand at about a 4" bore. I'd try to find a JY one though.

I got a nice iron 6.0 complete engine with 30K miles on it a few years ago for $1000, with all the accessories, 317 heads,intake, injectors, wiring harness etc. I've parted it out and am going to use the iron block and the crank for my next short block build. I only have about $300 in the block and crank after what I parted out. The block is damn near like new, I'm going to have it honed over 5 thou, and make a 365 out of it. I'm not "sloppying" this one, going to do everything by the book. I'm going to stay single turbo though, and just modify my huron speed kit to accept a bigger turbo. I think I can stand the rad up, and cut off the hot side merge and redo it with a T6 flange. My Huron Speed kit is a 2.5" hot side so it is certainly big enough to feed into a T6 flange. I may need to add a second waste gate or put a bigger one on it, I'm using a single PW46 right now, but that is easy enough. I'm thinking of having Jose at Forced Inductions build me one of those big S400 types with the 82 or 84 mm billet compressor wheels, and a 92mm turbine. I think the 365 cid will be enough to spool one of those without too much difficulty. My goal will be 1K wheel, and I'm going to use ARP main studs to help keep the caps from flexing and walking. I think having firm main bearing caps helps to minimize problems a flexing crank creates. This is a project for next winter though, I want to have fun with my car the way it is now. If I blow it up though, that will accelerate the timeline for the new short block.

Dennis you have only had your T4 single car together for a few months, I hope you enjoy it for a while before starting over.

Dennis5374

So a stock 5.3 will have trouble spooling two 7868s? I figured it'd be decent considering how fast my ls1 spools a single "full on by 2600 rpm " this is with an off the shelf tsp n/a cam.. I already have the pair of these . I have a complete long block lq4, as well as 3 other 5.3 blocks sitting in my shop. I'm new to the turbo game as Scotty said , as I've always had nitrous cars. So more cubes to spool the turbos? I'm going with the racetronix dual 340 pump kit and their fuel system. I'm gonna back it with a dual bap, so it should have no issue supporting 1500 hp . So tear down my perfectly good 6.0 and build a 408? I know people who have pushed bone stock 5.3 with a big single past what my 7868 could make spinning to the max . Open the ring gap, add some valve springs and head studs and you have a very potent bullet proof small block , would the stock 6.0 displacement be enough to spool the 7868s?

Nitroused383

iTrader: (10)

Skip the 340s and bap. Just get 2 walbro 450s.

1CAMWNDR

iTrader: (21)

What is the hard honest realistic goal of the vehicle? What vehicle...light or heavy? Just want a hp number or do you want fun on the street?

I see the F1-68 turbine is a 79mm inducer and the 68mm in 7868 is the outlet. That is big. it would be better suited as a single turbo on a 5.3. But a 79mm turbine inducer is gonna have a hard time driving a 78mm compressor I think. It is not efficient for a twin system I do not think.
EDIT: Then again....See DBRODS videos below... That looks like they will work just fine...
The Borg Warner S362 has a 61.5mm compressor being driven by a 76mm turbine wheel.....just 3mm smaller than the 79mm turbine you are talking about. S362 has much better leverage to get the compressor spinning AND is capable of flowing 75lb/min. So a pair of those should be able to flow enough for something insane like 1300 or so hp at the flywheel.

gnx7

iTrader: (28)

Agreed

DBRODS

iTrader: (1)

I had a SBE aluminum gen 4 5.3 back in 2012 and it would spool twin Turbonetics Tseries 7668s no problem. This was with 243 heads and a Tooley/LJMS stage 3 turbo camshaft and holley 92mm high ram. Here is a video of it spooling them.


Here is another video on aspault and 30psi with the Turbonetics.


This setup was pushed to 28psi and a little over 1200hp. I then swapped to Wiseco pistons and Callies rods, Tooley TFS 220 heads, 1/2" studs and Cooper ring gaskets, Holley dominator setup, and a pair of PTE CEA 6766s. Im pushing 35psi now.

1CAMWNDR

iTrader: (21)

Well now....that IS interesting....How does the 5.3 respond with the 6766 size vs the 7668? The "lunch" video appears to start around 4000rpm. Do the 6766s come on sooner?

28psi and 1200hp on a stock bottom end? Tell me that is NOT wheel horsepower....

DBRODS

iTrader: (1)

The Turbonetics would be all in at 4600rpm and the Precisions are all in by 4300rpm. The SBE would bend rods around 28psi and yes thats wheel HP. At 4200 pounds the truck trapped 143mph on 15-16psi. Ive never ran it at the track on higher boost cause the truck isn't track legal. The precisions make a lot more power than the Turbonetics did.

1CAMWNDR

iTrader: (21)

Insane.