LS3 - Is 550whp all motor feasible?

[christianchevell]

That's about the area I am aiming for when I do some LS7 small bore heads for my 428 stroker and accompany it with a MSD or other good intake, and a more radical stroker cam sometime, The ls3 is somewhat limited in intakes though that nice new one is out but spendy ,and semi long runner more for high rpm use not street/torque friendly its by LOD speedworks , with a big open plenum in the middle painted varying colors with LOGO its been on posts here. A fast does better the more radical the build just as other intakes can but are sheet metal or a huge Nelson or Edelbrock with double Tb's and most don't want to spend a fortune for heads and intake. I believe GPI came out with some good ls7 small bore heads on here just months ago...... And a nice dyno of the mule/ first to get a set on a stock short block ls3 cammed.

There for years Vararam had us going with a dual plenum intake with wide bowed long runners they said made 40+ and then they never made it to production while they were making copo's stuff.... We were robbed and it was plastic to dissipate heat also...and not too bad looking instead the VRX intake we waited for in the never ending thread became another cold air induction by Vararam. Getting HP to the equation is something that can be done but I am more building for torque and have more torque than HP now with like 486 , I used to have more HP with my stock cube ls3 and just the tsp 235/239 cam a CAI and LT with HFC I got 491 HP on its dynoing..

Numbers are nice ;a guy could theoretically cam the crap out of ls3 and go with long runners and get high HP...but like a long runner intake can help with HP numbers up top it hurts torque all along the curve and torque is what moves yah baby...believe me......
BUT going for a bench racer to get numbers on paper is not as important as having the torque..one shows how hard it moves you...Torque the HP shows how hard the engine worked while making that torque and is based off torque on dynos. And some dynos are much friendlier than others. I would trade some hp for torque anyday, and have. All along the curve and more right off the bat to be able to shred. Old school here no substitution for the cubic inch solution...LOL Wish I had like 560 cube LSX...LOL and just may some day.....but its needing a zl1 rear someday......

Anyway wheel hop kills axles and sticky tires catching then letting go then catching....as in wheel hop, a good set of trailing arms with poly bushings help the rear survive along with toes ..... don't expect much from stock ported heads as the heads already flow great and a real radical cam would need to be employed beyond what most places make for street/strip stage 3-4 as in .650 up lift to get to the stock cubed engine 550 hp realistically on a good dyno IMO... consider others mods, bushed trunnions, dogbone dampener, high volume pump, good oil like ls30, good catch can, etc....

IMO heads worth 5-10 hp realistically, and exponentionally better bang for $$$$ more if you were radically cammed ....remember theres a big world out there, guys running LS engines with things like .650, .700, .750 cams out there for drag racers /boats etc long runner twin carb monsters literally pumping out 700 N/A HP or spray it and get like 1000..... Bought my short block from Jerry at custom engine supply ;SAG and they sometimes post some monsters online in the machinist area/engine dyno. Most don't go too radical; and the most common aftermarket cams do take into account daily driving ability /longevity and other required mods taken to upgrade.

You should not loose hardly any torque with the Fast its not that much longer runner just better flowing more than stock and shines higher up some but does not loose the bottom end like other intakes,( sheet metal, midrise etc); one reason its around and MSD did not go ahead with a Airforce intake for the ls3 outdoing stock is hard..... Chasing a number can be spendy..... in order to use the increased flow to make its beneficial from larger porting to heads/larger heads flow numbers speed etc....you have to be able to implement it and a standard aftermarket cam is not that really radical to make so much Hp just compared to stock already great flow....remember stock ls3 heads flow over BBC ported heads numbers..... AND FAST and MSD intakes ( LS7) both benefit from more cubes exponential increases better bigger more demand for fuel etc....and everything to get to numbers close to 500 enough for most is spendy enough IMO for most who do drive daily like me...

[BFASTNOTLAST]

Some have done it already. It's a mixture of the right parts.

[lazerlemonta]

My friend Drth_V8R made 540 with a 346 and daily drove it no issue. 550+ LS3 is cake with a good recipe and will have tolerable manners. Some of the guys with stroker motors dont out perform LS3s. Just because you have stroke and a poor combo doesnt make you fast. Big bore motors is where the real power is at(bore larger then stroke). I have another friend with a 388 makes 673rwhp and 539trq. LS1tech has some great info OP in the gen IV and dyno section.

[Punisher_ATX]

570+rwhp is doable with heads cam FAST and proper supporting boltons =) Stock shortblock.

[2010reddevil]

Originally Posted by Punisher_ATX

570+rwhp is doable with heads cam FAST and proper supporting boltons =) Stock shortblock.

I would LOVE to see ANY H/C/I stock 376 cube LS3 make those numbers on a Mustang dyno.

[Punisher_ATX]

Its possible with compression and the correct heads

[Jason 98 TA]

Last week TSP had a customer with shelf PRC 260 heads, Stage 4.2 camshaft, Holley Intake & no piston notching make 543rwhp. 550rwhp is no problem with cutting the pistons and e85. No problem at all.

Jason
Texas Speed

[2010reddevil]

This is on a Mustang dyno? Pump 93 Octane fuel? Do post up the run, would like to see the run!

[Bo White]

I believe he was on a dynojet but the run is on TSP page.

[Avenging Orange]

I've ask before and I will again......why are you stuck on a specific number? HP numbers do not make the car. I can find 400hp cars blasting 500hp cars all day long. It's the right combination of hp, tq, drivtrain, suspension, etc. all working in harmony.

[Dylan1214]

I'm about to pull the trigger on a GPI Max package + E85 for my L99. Should put me around 530-540.

[KW Baraka]

Originally Posted by Bo White

alot of cylinder head, compression and camshaft yes.

Exactly what I was thinking!

Some 'serious' aftermarket heads, 12.5+:1 static compression, 250*+/260* LSA cam with 20*+ overlap, full intake and exhaust work.

Low RPM (<4000rps) power will suffer, drivability will suffer, but car will eventually go fast as hell as long as you can rev over 7000 RPMs.

KW

[hntrgthrs]

Originally Posted by Jason 98 TA

Last week TSP had a customer with shelf PRC 260 heads, Stage 4.2 camshaft, Holley Intake & no piston notching make 543rwhp. 550rwhp is no problem with cutting the pistons and e85. No problem at all.

Jason
Texas Speed

Which is why dyno numbers are a pretty meaningless tool.

Useful in bench racing, though.

[InFiD3ViL]

Originally Posted by Dylan1214

I'm about to pull the trigger on a GPI Max package + E85 for my L99. Should put me around 530-540.

Even with our drivetrain loss?