RockstarAutomotive

How much can you boost a stock 2002 Z06? I purchased this car with a pro charger on it. It looks like it has the stock fuel injectors. At some point the fuel system has to be upgraded. I currently see 6psi of boost. Can it handle 8 or even 10?

silver408z

The stock fuel system normally is maxed out around 500 whp. Cant really say how it will hold up based on pounds of boost.

FourG63 97GST

What he said, boost isn't a direct correlation with horsepower, but the standard answer to this is, the stock GenIII rods safe limits is around 650whp +/- 30hp, doesn't matter if it takes 5psi or 50psi to accomplish that.

neutron82

cylinder pressure is really what you have to look at... which procharger?

_zebra

yep - boost is a measure of air restriction; horsepower is more a result of air & fuel usage tempered by efficiency.
i wouldn't expect stock injectors to reliably take you very far.

edram454

stock fuel pump with boostapump and 60 pound injectors made 699 hp at 11 pounds of boost in a modified stock block ls6 engine on a mustang dyno. that is fact. everybody has an opinion. Mine is fact. Take it to a reputable tuner. One that specializes on ls engines and has a long list of customers that can back up his claim as a professional tuner. dont listen to anyone. Only listen to the experienced professional tuner.

_zebra

i was under the impression we were talking stock injectors here.

Turbo-Geist

edram454 saw the words "stock" and "fuel" and it automatically triggered him to continue his quest to claim 699rwhp on a stock 190lph fuel pump with a boost-a-pump. A stock fuel pump plus boost-a-pump flows close to what a single bosch 044 would flow, i.e., 285 lph. With 285 lph supplied by the pump and 60lb/hr injectors and 11psi, I think we all know how much power this fuel system will support.

More info on dyno racing can be found here: Dyno Magic and Mythical HP

Turbo-Geist

Are you advising the people in this thread that it is safe to use a stock fuel pump and a boost-a-pump for 699rwhp?? Please post up the dyno sheet. What you are saying in this thread is termed a mutual exclusivity.

You said:
a: 699hp on a stock ls6 engine
b: Stock fuel pump with a boost-a-pump

It is either a or b but not a and b at the same time.

The car could make 699rwhp or the car may have only a stock fuel pump, however both of those can't exist simultaneously on the same car and be considered true.

Once again, are you advising people that only professional "tooners" at a shop can tune a car?? What constitutes a professional tuner in your opinion? We can dig up multiple examples on this forum over the years of shops blowing engines and giving people cookie cutter tunes. There are plenty of hobbyists in this forum who manage to tune their own vehicles without mishap and then outrun shop built and "tooned" cars.

_zebra

well, if anything, thanks for reminding me to double-check that a new fuel pump got invoiced & added on mine... that almost got lost in the last few weeks of 'fun' we've been dealing with.
mine (stock w/ BAP) was coming up on its limits at mid-600s and 60# (really ~73# at LS rail pressures)

Turbo-Geist

Glad to know you were able to avoid an issue. Which pump are you installing and will you be using the boost-a-pump again?

A 255, boost-a-pump, and meth will usually get you pretty far on a stock bottom end and forced induction.

_zebra

we settled on pulling the BAP and rewiring for, i wanna say, a 450. should leave plenty enough headroom for peace of mind.
no meth - was gonna do a direct-port setup but scratched that plan for an intercooler chiller. spraying meth before the rotors on a PD really lessens the effect & runs the risk of delaminating the lobes (reducing compression/efficiency).

Water_Walker

Ran out of injector on a cam only car at 435rwhp

Lost entire engine at 9psi at 611rwhp. The tune was the issue..far too hot. Car lasted 1500 miles after boost.

No doubt about it, 600+ boosted on a stock ls6 is risky. Many have gone miles and miles and many have not...including me. Listen to Turbo-Geist, Blownblue, Neutron, etc. and learn.

z0stix

my stock ls6 block stock 243 heads and torque v2 cam with a D1 around 11psi, 60lbs injectors, 255 pump, kb boost a pump, alkycontrol meth kit, survived for a good 3 years making about 670hp....one day I noticed alot of smoke coming out of the oil breather and I knew somthing was up...took it apart and when removing piston 7 a ring land had a fracture in two seperate locations, very small but enough for a peice to be broken off, even the cylinder walls were unharmed....so I tossed in a forged 383 i bought off a friend for cheap,it has a little more compression, so I added ls9 head gaskets, arp head studs, jam cam, a&a secondary drive and now its happy with 803hp with 16psi

Rkreigh

I learned a bit about FI and hyper pistons tuning the little turbo v6 buick

on that engine they are stronger than the pistons in the ls6 which has fairly weak pistons as the rings are higher up for low emissions

you need to tune for zero detonation and certainly not lean out from lack of fuel.

I'd recommend e85 or direct port alchy injection to make sure you are getting plenty of octane and 10 psi or so and 600 should last a long time

watch timing and make sure there is no detonation anywhere on the dyno or street pulls and don't get greedy or you'll pop a piece out of the piston as have many others

good luck, the thin wall ls6 block isn't a great choice either, I have a ttix ls6 with forged internals that is "maxed out" largely due to the block.

seems right around 900 is the sweet spot and limit for the block before cyl pressure will split and crack the liners

Cheesecake 07