Gen3Benz

iTrader: (4)

A friend of mine recieved an 400hp/420tq LS1 fron turnkey engine supply. i checked the heads they were untoched 241's and a normal f-body ls1 intake.

the guy on the phone said they generate more like 420hp. when asked what was modded he said they just add headers/glasspacks and tuning with a stand-alone delphi ecm(with speed density, no maf). i asked if it was cammed and it said it had factory .500 cam in it.

nothing is touched in the engine.

dont these engine's produce like 320hp at the flywheel stock?

how can you generate 100hp with just stright exhaust and tuning? sounds like a crock to me

Colonel

LS1s make about about 350-370 at the flywheel. They make anywhere between about 285-320 RWHP stock (depending on many factors including year model and drivetrain selection.)

Do people actually still use glasspacks? LOL!

Gen3Benz

iTrader: (4)

they make the engines for sandrails, they have the glass packs integrated into the headers. the headers go straight out to the side then back.

66ImpalaLT1

Actually stock LS1's make like 400-420 at the flywheel when equipped with headers and bolt-ons and when properly tuned.

The only person I've heard of trying this on an engine dyno is Myron of TPIS.

Eric

soundengineer

iTrader: (16)

isnt that technically what my dynomax bullets are???

gymratt

iTrader: (3)

Dynomax uses Continuous Roving Fiberglass (CRF) technology for sound control. I think the material is much lighter or smaller amount used than the old cherry bombs. My brother had cherry bombs on his ride in the late 70's, they were so friggn heavy they kept falling off due to welds failing from all the weight. My dynomax race bullet was suprisingly light.

Colonel

Bullet mufflers are not glasspacks...but they sure look alot like 'em!

Cal

iTrader: (1)

Dynomax claims they have some kind of ceramic stuff in them; that should make them last longer than a traditional glass pack.

The LS1 engine in an Fbody is rated either at 320 or 325 hp depending on whether it's an SS, Firehawk or just a standard Camaro or Firebird. The LS1's that come in Corvettes are the ones rated for 350 hp, but they have a different cam than the Fbody version. The cam with 0.500" lift that he was refering to only comes in the Corvette LS1. From what I've seen, these factory flywheel ratings are pretty close for the settup as built by GM, i.e. no mods.

Colonel

"From what I've seen, these factory flywheel ratings are pretty close for the settup as built by GM, i.e. no mods."

Cal, you tellin' me you believe an engine rated at 305 FWHP can logically put down the 310-320 RWHP that many stock cars do? GM rates their engines at the flywheel while a chassis dyno obviously tests them at the ground.

GM WAY underrates these engines.

MYTURBOT/A

I think all LS1s had a .500 lift cam in them until 2000 or 2001 when they went to the truck cam and other then the zo6 the vette and f-body ls1 were the same internally and dynoed close to the same. I also think that a ls1 with good exhaust and tune could put 420hp to the flywheel easy. just my .02 cents

Gen3Benz

iTrader: (4)

how about the use of speed density over maf?

i thought maf was much better at seeing airflow than speed density with a low vacuum cam, if the cam was upgraded.

crewdawg16

yes, but without the MAF up front, you can take advantage of things like the 90mm throttle bodies coming out for the 90mm FAST LSX intakes, because right now the biggest MAF is 85 mm I believe. So you lose that restriction point. More air = more power

Gen3Benz

iTrader: (4)

yeah but without a big cam you wont get any more air....i just thought maf was better for breathing cams. not to mention these engines are gm crate engines.

Scott Turvey

are you talking about the turnkey engine supply motors being gm crate engines?

samz28

Speed density is fine in with a TPS. You can crossover the TPS signal at low rpm's to run alpha-n rather than speed density to maintain fueling. Most race cars like sandrails i'm guessing don't care much about gracefulness of low load and low idle, but more about WOT and hauling much ***

almost every standalone uses a TPS and map sensor, rarely do they incorporate maf signal unless its some sort of piggyback or super custom rig.

i don't really consider maf-tweakers standalone, but alot of folks tout some as such. More like piggybacks.

DALLAS

Hehe, I had a glasspack. I have the old setup with a cutout now though.

Gen3Benz

iTrader: (4)

yeah. i called them, they said they are factory motors with a delphi ecm.
running speed density without 02's.

DeepBlueZ

My 337 RWHP divided by .80 (20 % drivetrain loss) = 421.25 flywheel HP...Bolt on ONLY, stock TB, stock MAF, No LS6 intake.

On a cold day, 358 Actual RWHP divided by .8 = 447.5 Actual flywheel HP...

these motors can do it stock, if they're teamed with good bolt-ons.

now that i think about it 421 horsepower under the hood is pretty cool!!!!

kjmdrumz3

iTrader: (1)

Actually you multiply the fwhp to get the rwhp, but since we are working in reverse: 406 fwhp X 0.83 (drivetrain loss....you lose NO MORE than 17%on an A4, around 12-14%on a M6)= 336.98rwhp. So you ALOT closer to 406 than 420-whatever.

DeepBlueZ

Actually those two would be the same thing.....dividing rear wheel horsepower by a fraction is the inverse of multiplying flywheel horsepower by the same fraction, thus the two are equivalent... since i verified REAR WHEEL hp on a chassis dyno and not the FWHP on an engine dyno, i would kind of HAVE TO use this wouldnt I?

also, with a loose converter, you CAN lose more than 17%, i've had 4 dyno techs verify that high stalls leave power in the transmission...20% is not unheard of...usually you hear around 16-18% on a stock TC and 19-22% on a loose high stall....hence my guess of 421 fwhp...if i've been misinformed about this, someone let me know, but just about everyone i talk to seems to agree that its accurate....

for the sake of argument i will use your numbers anyway...how did get 406 hp?? i kind of doubt you picked numbers out of the air until you were able to multiply your way to 337 rwhp...you divided 337 by .83 and got 406...now do it in reverse...see?

Lastly, to prove what i was going for anyway, even with the 17 percent loss, the 400 hp rating of your turn key engine is accurate....