How many LS3's would a Corvette chuck if a Corvette could chuck..
03-17-2015, 04:07 PM
#1
Burning Brakes
Thread Starter
How many LS3's would a Corvette chuck if a Corvette could chuck..
A little alliteration and humor to quell the pain of yet another bad engine. I'm commiserating as well as sharing some tech. In my 05' C6 roadrace vette my engine count stands at 4 in 2 years, starting build #5.
Original LS2: Touched the rev limiter and valve kissed piston, snapped, shattered piston, rod windowed the block AND the ARE oil pan. Oil hit the headers and caught fire but quickly put itself out. LESSON: Replace valve springs often! Factory hyperutectic (sp?) pistons are crap and when they let go the rods punch holes everywhere and oil spillage = fire.
Replacement #1: LS3: $3700 craigslist longblock with blower cam, made 650rwhp in another Vette locally. The engine was well cared for and tuned well and monitored properly. Dropped it in AS-IS!: added back dry sump (with obligatory big money replacement dry sump pan), 16lb clutch, 3" full exhaust and netted 455rwhp/427tq. Lasted for 16 months and then I moneyshifted it in June last year. Valve kissed piston, snapped, shattered piston, rod windowed the block AND the ARE oil pan. Ensuing fire also torched the $1100 engine harness and snapped the bellhousing.
LESSON #1: Calm down and if the shift doesn't feel right, don't let out the clutch.
LESSON #2: Dang factory cast pistons..
LESSON #3: Fire sucks!
Replacement #2: LS3 (L92):stock bottom end completely gone through, ported exhaust side only, 5 angle valve job, and fully ported/polished chamber, decked for compression (11.2), and Brian Tooley spec'd road race cam. Dyno'd 505rwhp/480rwtq (SAE). December 21st: 30 minutes on the dyno for tuning. 33 minutes on track and BOOM! Rod bolt let go. Rod punched hole in block and windowed the pan, caught fire, fire extinguisher emptied. Harness was saved due to fire wrapping the entire thing. Wife is getting very tired of this.
Lesson #1: Get more fire nozzles
Lesson #2: Never use stock rod bolts.
Lesson #3: Gary at ARE does have a frequent flyer discount program for oil pans.
Lesson #4: Wrap the wire harness!!
Replacement #3: LS3 with fully forged shortblock and 2000 miles, car it was in was wrecked and engine sold. Turns out rings shot, bore needed hone, bearings shot. Engine shop missed the broken head studs and didn't mention to me an oil pan bolt was cracked (on the outside) and welded<- that should have been the clue that the block was in trouble.. . They also should have caught the broken head studs when they chase all the bolt holes.. obviously that never happened. Speed shop removed the head studs (took 4 hours, didn't charge me, and didn't have the heart to tell me given all I'd gone through already). Engine goes together with LS3 heads Stage 1 ported by Frankenstien racing heads, 11.0 compression, same (new) BTR camshaft, engine makes 515rwhp and was at 23 degrees of timing and 11.7AFR.. in other words, it was going to make more. Ran (2) easy 10 minutes sessions primarily for data logging and creeping up on the tune safely this past weekend and it developed an oil leak. Put in on a lift and a small chunk of the block is missing at the rear (and leaking) and one of the oil pan bolts is leaking (through the hole, not at the gasket). I thought I felt a small vibration (was thinking it was guibos), now I know the engine block was coming apart.
Lesson #1: If an LS3 block sustains ANY amount of structural damage, chuck it in the trash and start over.
Lesson #2: Brian Tooley Racing also has a frequent flyer program!
Replacement #4: will be a brand new LS3 block with everything transferred over as-is because for the first time I didn't trash the engine. In all the carnage I described, not one oil pan, block, crank, intake, oil cooler, or set of oil lines survived. I did save 2 cylinder heads out of 8. Most times, when an LS blows, it blows BIG!!!
So in summary:
New blocks, ARP rod bolts, forged pistons, good fire system (with nozzles aimed between headers and block) are a bare minimum. I share this so that you don't go through the same ridiculous learning process I did.
Jerry (reluctant LS3 weaklink expert)
Original LS2: Touched the rev limiter and valve kissed piston, snapped, shattered piston, rod windowed the block AND the ARE oil pan. Oil hit the headers and caught fire but quickly put itself out. LESSON: Replace valve springs often! Factory hyperutectic (sp?) pistons are crap and when they let go the rods punch holes everywhere and oil spillage = fire.
Replacement #1: LS3: $3700 craigslist longblock with blower cam, made 650rwhp in another Vette locally. The engine was well cared for and tuned well and monitored properly. Dropped it in AS-IS!: added back dry sump (with obligatory big money replacement dry sump pan), 16lb clutch, 3" full exhaust and netted 455rwhp/427tq. Lasted for 16 months and then I moneyshifted it in June last year. Valve kissed piston, snapped, shattered piston, rod windowed the block AND the ARE oil pan. Ensuing fire also torched the $1100 engine harness and snapped the bellhousing.
LESSON #1: Calm down and if the shift doesn't feel right, don't let out the clutch.
LESSON #2: Dang factory cast pistons..
LESSON #3: Fire sucks!
Replacement #2: LS3 (L92):stock bottom end completely gone through, ported exhaust side only, 5 angle valve job, and fully ported/polished chamber, decked for compression (11.2), and Brian Tooley spec'd road race cam. Dyno'd 505rwhp/480rwtq (SAE). December 21st: 30 minutes on the dyno for tuning. 33 minutes on track and BOOM! Rod bolt let go. Rod punched hole in block and windowed the pan, caught fire, fire extinguisher emptied. Harness was saved due to fire wrapping the entire thing. Wife is getting very tired of this.
Lesson #1: Get more fire nozzles
Lesson #2: Never use stock rod bolts.
Lesson #3: Gary at ARE does have a frequent flyer discount program for oil pans.
Lesson #4: Wrap the wire harness!!
Replacement #3: LS3 with fully forged shortblock and 2000 miles, car it was in was wrecked and engine sold. Turns out rings shot, bore needed hone, bearings shot. Engine shop missed the broken head studs and didn't mention to me an oil pan bolt was cracked (on the outside) and welded<- that should have been the clue that the block was in trouble.. . They also should have caught the broken head studs when they chase all the bolt holes.. obviously that never happened. Speed shop removed the head studs (took 4 hours, didn't charge me, and didn't have the heart to tell me given all I'd gone through already). Engine goes together with LS3 heads Stage 1 ported by Frankenstien racing heads, 11.0 compression, same (new) BTR camshaft, engine makes 515rwhp and was at 23 degrees of timing and 11.7AFR.. in other words, it was going to make more. Ran (2) easy 10 minutes sessions primarily for data logging and creeping up on the tune safely this past weekend and it developed an oil leak. Put in on a lift and a small chunk of the block is missing at the rear (and leaking) and one of the oil pan bolts is leaking (through the hole, not at the gasket). I thought I felt a small vibration (was thinking it was guibos), now I know the engine block was coming apart.
Lesson #1: If an LS3 block sustains ANY amount of structural damage, chuck it in the trash and start over.
Lesson #2: Brian Tooley Racing also has a frequent flyer program!
Replacement #4: will be a brand new LS3 block with everything transferred over as-is because for the first time I didn't trash the engine. In all the carnage I described, not one oil pan, block, crank, intake, oil cooler, or set of oil lines survived. I did save 2 cylinder heads out of 8. Most times, when an LS blows, it blows BIG!!!
So in summary:
New blocks, ARP rod bolts, forged pistons, good fire system (with nozzles aimed between headers and block) are a bare minimum. I share this so that you don't go through the same ridiculous learning process I did.
Jerry (reluctant LS3 weaklink expert)
Last edited by JerryTX; 03-17-2015 at 04:09 PM.
03-17-2015, 05:04 PM
#4
Safety Car
A little alliteration and humor to quell the pain of yet another bad engine. I'm commiserating as well as sharing some tech. In my 05' C6 roadrace vette my engine count stands at 4 in 2 years, starting build #5.
Original LS2: Touched the rev limiter and valve kissed piston, snapped, shattered piston, rod windowed the block AND the ARE oil pan. Oil hit the headers and caught fire but quickly put itself out. LESSON: Replace valve springs often! Factory hyperutectic (sp?) pistons are crap and when they let go the rods punch holes everywhere and oil spillage = fire.
Replacement #1: LS3: $3700 craigslist longblock with blower cam, made 650rwhp in another Vette locally. The engine was well cared for and tuned well and monitored properly. Dropped it in AS-IS!: added back dry sump (with obligatory big money replacement dry sump pan), 16lb clutch, 3" full exhaust and netted 455rwhp/427tq. Lasted for 16 months and then I moneyshifted it in June last year. Valve kissed piston, snapped, shattered piston, rod windowed the block AND the ARE oil pan. Ensuing fire also torched the $1100 engine harness and snapped the bellhousing.
LESSON #1: Calm down and if the shift doesn't feel right, don't let out the clutch.
LESSON #2: Dang factory cast pistons..
LESSON #3: Fire sucks!
Replacement #2: LS3 (L92):stock bottom end completely gone through, ported exhaust side only, 5 angle valve job, and fully ported/polished chamber, decked for compression (11.2), and Brian Tooley spec'd road race cam. Dyno'd 505rwhp/480rwtq (SAE). December 21st: 30 minutes on the dyno for tuning. 33 minutes on track and BOOM! Rod bolt let go. Rod punched hole in block and windowed the pan, caught fire, fire extinguisher emptied. Harness was saved due to fire wrapping the entire thing. Wife is getting very tired of this.
Lesson #1: Get more fire nozzles
Lesson #2: Never use stock rod bolts.
Lesson #3: Gary at ARE does have a frequent flyer discount program for oil pans.
Lesson #4: Wrap the wire harness!!
Replacement #3: LS3 with fully forged shortblock and 2000 miles, car it was in was wrecked and engine sold. Turns out rings shot, bore needed hone, bearings shot. Engine shop missed the broken head studs and didn't mention to me an oil pan bolt was cracked (on the outside) and welded<- that should have been the clue that the block was in trouble.. . They also should have caught the broken head studs when they chase all the bolt holes.. obviously that never happened. Speed shop removed the head studs (took 4 hours, didn't charge me, and didn't have the heart to tell me given all I'd gone through already). Engine goes together with LS3 heads Stage 1 ported by Frankenstien racing heads, 11.0 compression, same (new) BTR camshaft, engine makes 515rwhp and was at 23 degrees of timing and 11.7AFR.. in other words, it was going to make more. Ran (2) easy 10 minutes sessions primarily for data logging and creeping up on the tune safely this past weekend and it developed an oil leak. Put in on a lift and a small chunk of the block is missing at the rear (and leaking) and one of the oil pan bolts is leaking (through the hole, not at the gasket). I thought I felt a small vibration (was thinking it was guibos), now I know the engine block was coming apart.
Lesson #1: If an LS3 block sustains ANY amount of structural damage, chuck it in the trash and start over.
Lesson #2: Brian Tooley Racing also has a frequent flyer program!
Replacement #4: will be a brand new LS3 block with everything transferred over as-is because for the first time I didn't trash the engine. In all the carnage I described, not one oil pan, block, crank, intake, oil cooler, or set of oil lines survived. I did save 2 cylinder heads out of 8. Most times, when an LS blows, it blows BIG!!!
So in summary:
New blocks, ARP rod bolts, forged pistons, good fire system (with nozzles aimed between headers and block) are a bare minimum. I share this so that you don't go through the same ridiculous learning process I did.
Jerry (reluctant LS3 weaklink expert)
Original LS2: Touched the rev limiter and valve kissed piston, snapped, shattered piston, rod windowed the block AND the ARE oil pan. Oil hit the headers and caught fire but quickly put itself out. LESSON: Replace valve springs often! Factory hyperutectic (sp?) pistons are crap and when they let go the rods punch holes everywhere and oil spillage = fire.
Replacement #1: LS3: $3700 craigslist longblock with blower cam, made 650rwhp in another Vette locally. The engine was well cared for and tuned well and monitored properly. Dropped it in AS-IS!: added back dry sump (with obligatory big money replacement dry sump pan), 16lb clutch, 3" full exhaust and netted 455rwhp/427tq. Lasted for 16 months and then I moneyshifted it in June last year. Valve kissed piston, snapped, shattered piston, rod windowed the block AND the ARE oil pan. Ensuing fire also torched the $1100 engine harness and snapped the bellhousing.
LESSON #1: Calm down and if the shift doesn't feel right, don't let out the clutch.
LESSON #2: Dang factory cast pistons..
LESSON #3: Fire sucks!
Replacement #2: LS3 (L92):stock bottom end completely gone through, ported exhaust side only, 5 angle valve job, and fully ported/polished chamber, decked for compression (11.2), and Brian Tooley spec'd road race cam. Dyno'd 505rwhp/480rwtq (SAE). December 21st: 30 minutes on the dyno for tuning. 33 minutes on track and BOOM! Rod bolt let go. Rod punched hole in block and windowed the pan, caught fire, fire extinguisher emptied. Harness was saved due to fire wrapping the entire thing. Wife is getting very tired of this.
Lesson #1: Get more fire nozzles
Lesson #2: Never use stock rod bolts.
Lesson #3: Gary at ARE does have a frequent flyer discount program for oil pans.
Lesson #4: Wrap the wire harness!!
Replacement #3: LS3 with fully forged shortblock and 2000 miles, car it was in was wrecked and engine sold. Turns out rings shot, bore needed hone, bearings shot. Engine shop missed the broken head studs and didn't mention to me an oil pan bolt was cracked (on the outside) and welded<- that should have been the clue that the block was in trouble.. . They also should have caught the broken head studs when they chase all the bolt holes.. obviously that never happened. Speed shop removed the head studs (took 4 hours, didn't charge me, and didn't have the heart to tell me given all I'd gone through already). Engine goes together with LS3 heads Stage 1 ported by Frankenstien racing heads, 11.0 compression, same (new) BTR camshaft, engine makes 515rwhp and was at 23 degrees of timing and 11.7AFR.. in other words, it was going to make more. Ran (2) easy 10 minutes sessions primarily for data logging and creeping up on the tune safely this past weekend and it developed an oil leak. Put in on a lift and a small chunk of the block is missing at the rear (and leaking) and one of the oil pan bolts is leaking (through the hole, not at the gasket). I thought I felt a small vibration (was thinking it was guibos), now I know the engine block was coming apart.
Lesson #1: If an LS3 block sustains ANY amount of structural damage, chuck it in the trash and start over.
Lesson #2: Brian Tooley Racing also has a frequent flyer program!
Replacement #4: will be a brand new LS3 block with everything transferred over as-is because for the first time I didn't trash the engine. In all the carnage I described, not one oil pan, block, crank, intake, oil cooler, or set of oil lines survived. I did save 2 cylinder heads out of 8. Most times, when an LS blows, it blows BIG!!!
So in summary:
New blocks, ARP rod bolts, forged pistons, good fire system (with nozzles aimed between headers and block) are a bare minimum. I share this so that you don't go through the same ridiculous learning process I did.
Jerry (reluctant LS3 weaklink expert)
03-17-2015, 05:52 PM
#6
Burning Brakes
Thread Starter
Thanks for the support guys and yes my wife is an angel! I do Road Racing (NASA) and have always had a 7000 or 7100rpm rev limit but I am adding a shift lift that turns on at 6500RPM to encourage me to have all the shifts done by 66-6700RPM. The cam BTR spec'd is all done by 6800 so overrev is only to avoid a shift right before a turn. A stock replacement is not in the cards as I want to avoid the rod bolts and pistons at all costs.
03-17-2015, 06:07 PM
#8
Racer
Sorry about your luck. Been there done that in my time with motors... Always seems to me that used crap always blows up. (Thinking its a good deal at the time) Replace everything with new has been my recent motto. Sucks but atleast you know your not rolling the dice with someone else's problem they sold you or reusing old motor parts of your own motor that is due to go boom.
Hope you have a safe, fun and low maintenance season.
Hope you have a safe, fun and low maintenance season.
03-17-2015, 07:25 PM
#10
Burning Brakes
Thread Starter
An LS9 block is very attractive at this point! Andy, thank you for the input and well wishes. My brother also races and describes himself as a "while your in there" kinda guy. In other words, while you are in there rebuilding the engine, replace/upgrade/strengthen. I'm quickly swinging to his point of view..
03-18-2015, 04:34 PM
#11
Drifting
The SCCA Trans Am 2 LS3's as built by Katech, Wegner & Schwanke have been very reliable. Most have been three stage dry sump setups...a few have been two stage scavenge systems, using the stock pressure pump.
In 2013 Kurt Roehrig put about 5000 racing miles on his Schwanke LS3 before taking it out and saving it for a spare.
These make about 500 hp to the flywheel with a restrictor, about 550 without.
They have a 6800 rpm rev limit.
These cars lap Sebring around 2:11-13 and Daytona around 1:52-54.
In 2013 Kurt Roehrig put about 5000 racing miles on his Schwanke LS3 before taking it out and saving it for a spare.
These make about 500 hp to the flywheel with a restrictor, about 550 without.
They have a 6800 rpm rev limit.
These cars lap Sebring around 2:11-13 and Daytona around 1:52-54.
03-18-2015, 05:57 PM
#12
Pro
Pro Mechanic
Wow Dont think title is fair to the LS3s. Dont buy used junk! Racing & overreving stock stuff isnt good either.
I wont put used engines in customers street cars.
0 LS engine failures in 15 years of racing them. 0 customer engine failures. Did have a couple close calls with customers pushing valve spring service life.
I wont put used engines in customers street cars.
0 LS engine failures in 15 years of racing them. 0 customer engine failures. Did have a couple close calls with customers pushing valve spring service life.
03-18-2015, 08:11 PM
#13
Burning Brakes
Been down the same road too many times. Finally found out you can't beat a 480hp crate motor with a 3 stage dry sump. Keep the revs around 6600.
03-19-2015, 02:18 PM
#14
Advanced
Member Since: Nov 2013
Location: Redmond OR
Posts: 80
Likes: 0
Received 0 Likes
on
0 Posts
Wow Dont think title is fair to the LS3s. Dont buy used junk! Racing & overreving stock stuff isnt good either.
I wont put used engines in customers street cars.
0 LS engine failures in 15 years of racing them. 0 customer engine failures. Did have a couple close calls with customers pushing valve spring service life.
I wont put used engines in customers street cars.
0 LS engine failures in 15 years of racing them. 0 customer engine failures. Did have a couple close calls with customers pushing valve spring service life.
03-19-2015, 07:44 PM
#15
Racer
If it helps, I enjoyed the read. It also makes me feel VERY good about the reliability of my setup. Simply curious - what valve springs have you been using?