americanmusl

I've been lurking here for some time and would like some feedback on a little incident which had occured recently occured but first some background(this will be a tad long!):
I purchased this car w/7500K miles from an aquaintance for 45K(DRM C500RSR 2000 Coupe Corvette...the complete package-Ls1 382 stroker w/4.10's in the rear(forged/billet everything on bottom with 4340 Lunati Crank, CNC ported heads w/4 angle SS valve job and titanium retainers 202/160(so it had good parts!) w/upgraded suspension, accusump, pumps, coolers etc. The car, other than a severe detonation problem, ran strong and passed Calif smog due to small Lunati cam. I took it to Fontana Calif Speedway with Speedventures shortly after changing all fluids with a brand called "Pure Power" and ran for about 15 minutes until bolt in crank pulley backed out and spewed oil for a short time. Repaired the problem and was told no damage otherwise. Because of my nature I decided to refresh the entire top end with 205 AFR heads ported to 71CC's, Comp Cams 228/232, 595/588 on 114 LSA, LSX 90mm intake with 36lb bosche injectors, 90mm Nick Williams TB modified MAF and KooKs L/T headers/exh system with 3" X pipe(Magnaflow). I won't give detail as to who did the work as yet but the car produced 470RWHP and 440RWTQ...I set this up for more of a road racing/daily driver application so the power band was excellent through 3200-6600 RPM's.

While the car was apart, some odd things were noted: .024 piston over deck clearence on all pistons heights, 11.9:1 CR with 224/565, 114 cam(can you say ping!) Stretched timing chain(not double roller)...does the piston clearence strike anyone odd? It did my engine builder! I'm new to LS1 technology...more old school here! All else appeared fine.

On to the track: on the first warm up lap at WIllow Springs big track at turn 5 and 6, the DIC lights up with bells and whistles "LOW OIL PSI" I checked my analog and it read maybe 5PSI at 4400RPMs (no loss of power, no oil clouds and temp read 220...heard clitty clacking and idled into the pits. Remind you this brand new set up only 500 miles new...towed it into builder explained my problem and started up...some of same noise but not as intense and oil at 23PSI but no increase with RPM increase...left it there for further diagnosis...2 days later with out tearing it apart, I'm told it's a spun main bearing possibly due to oil pump failure...does the LS1 have a weak oil pump? Builder tells me if they were not ported the plungers had tendency to stick!
Also, possibly cam bearing could have spun and if so block is junk do to fact that you can't put ovesize bearings cause block is tapped out on material...truth? I'm trying to keep calm as the builder appears to be working with me thus far as I just dropped 9K in the !@#$@$!@ thing!

So, I suppose what feedback I'm requesting other than what has already been stated, is the Plus's and Problems associated with the LS1 engines, Stroker motors, suggestions and or similar experiences or Doug Rippie issues...
I'm thinking of replacing the clutch while the motor will eventually be out...has centerforce in it now with no issues at 11K miles...suggestions?

Thanx for letting me vent

2000 Tran Zam

iTrader: (2)

from what i hear, 99 and older ls1 oil pumps are known to malfunction. also, check the rocker arms to see if they have blown up at all and they could have dropped the needle bearings into the oil pump. thats what happened with my ls1, just might be a thought :dunno:

goober35

iTrader: (1)

Well the stock ls1 oil pump is not the best peice in the motor. From what i read you like to do some road racing. From experience when you take elongated turns the oil will shift in the pan and away from the pick up tube. Now when the pan runs dry and no oil goes to the bearings you will spin one. This is not the pumps fault it is realy a design fault. You need to run an exstra quart of oil in the pan.

americanmusl

Forgot to mention my Pumps and Accusump were on...3 qt reserve for low pressures!

goober35

iTrader: (1)

Sounds like it did not help to me.

strokedls1

iTrader: (1)

The .024 out of bore is a bit much if you ask me. I run .002 out of bore. If you say you have had a lot of detonation then that may have contributed to your problems. Detonation could have caused some damage to a rod bearing. Not saying that it is the case, but just to say it could be a contributing factor. The road race stuff can be an issue like already stated. Maybe your extra storage check ball failed and didn't provide those extra three quarts. The only way to get to the bottom of it is to tear the motor down. If you are the orginal purchaser of the short block you may get a deal on replacement parts, but full warranty on a racing engine usually doesn't happen. You would have to prove that something was assembled incorrectly to try to get recourse. Good luck with it.

SAM98WS6

mine was .007" out of the bore but otherwise our motors are very similar. I was 480rwhp/440rwtq with ~10.5:1 but with a much more agressive camshaft. AFR 205s are nothing special but they took care of the pining issue I assume at 76cc.
Im sure DRM didnt use the stock oil pump without cleaning/porting it. IF they did or your builder did they are both stupid.
But as far as the problem...im assuming its coming apart...why speculate?..check the main clearance and torque..oil pump and pickup etc. Im curious now.

marc_w

Would the low oil pressure show up only after the 3 quarts are used up?

americanmusl

As far as the accusump issue in relation to oil psi, that does seem odd!

americanmusl

Now I just don't know what to think ...perhaps I'm cursed!

Get this! here's the latest update...builder finally tore engine partially apart... and this is what he found: thrust washer disintegrated, metal parts found in STOCK oil pump elsewhere in system, no blueing anywhere and scortching on crank journal near thrust washer, rod bearing clearances found to be .018 all of them, heads/ cam/ valve train appear ok but builder wants to replace springs in fear that they were heated to compromise heat treating...good news is that all internals appear forged aluminum/steel crank etc...just useless now! Rippie was the orig builder in 2000(remember only 11000 miles on stroker)...do the rod tolerances seem unusual to anyone? Stock oil pump? what gives!

strokedls1

iTrader: (1)

Usually .0025 is what I have seen on the lsx engine builds that I have done. My machine shop guy had to grind a little off the thrust washer to get it to rotate perfectly on my motor now. Sounds like someone dropped the ball with the dimmensions on your build.

SAM98WS6

mine were .0024rod and .0025 main....0018 isnt out of line
stock oil pump is a big no no
change the springs to be safe.

XTrooper

FYI: The OEM oil pumps, particularly in the 1999 model year cars, are a known issue. I had the oil pump in my 1999 Camaro SS which failed completely with no previous warning signs at 14,000 miles. GM replaced it without charge and without a word of complaint.

LASTLS1

iTrader: (7)

IMO, I don't think pushing these engines with stroker kits are going to go 50k miles. Not that they are junk, just that we tend to drive them harder,, extra stress! I would have torn the engine apart myself. I have had issues and I always want to see the problem for myself first hand. Maybe a second opinion FIRST! Freak accidents happen, but it seems that LS1 engines are not the same as SBC engines. I had many engine builders I called said they "were not set up to do LS1's". So it seems someone really needs to know what they are doing to make an engine last. To put one together, no problem. To make it last and make power is a different story! Give the builder a chance to help you out. Give praise if he does. Most will help if you give them the chance. It seems once you **** them off, or start with the flames, YOU DONE! I don't blame them, I would be the same. I would say tear it down, make sure EVERYTHING is right! As long as it's down and apart do it right. It sucks, but it's part of the game. Use your head, everything will work out. Good luck and keep us posted.

racecar

When I read that you had major spark knock issues, I thought here goes the bearings. My buddy blew up an LS1 motor road racing WITHOUT an Accusump. He ran it out of oil in the corners and the rod bearings let go. No big surprise there. But the tear down also revealed that the motor had been knocking (stock CR) so much that it ate one of the pistons down to the top ring groove, and was melting on others. Too much timing in the computer and not enough retard can have some drastic results, to pistons, and the bottom end. That sounds like the start of the problems. You can blame the motor guy, but the only guarantee in racing is "when it blows up, you get to keep all of the pieces".

americanmusl

day? what day is it again...don't even think I remember what color the car is! Well, after much feedback from everyone and my own intuition, I've ordered a LPE shortblock for 2095.00 bal and blueprinted, a upgraded timing chain(don't like the 2x rollers) and a ported LS6 oil pump...this will be a brand new engine assembly with all the bucks I've spent once together..going to let LAPD assemble with new Dual Friction clutch and that's it...I'm done! I figure with the 4.10's, usable torque should be fine and power with upper end should still be SOTP's...this car is not used for drag but dailey driver and DE's...My 2002 Z car did pretty damed good with 395 at rear with minor bolt on's! This car should still surpass that!

So here is the finale!
My 2700.00 Lunati crank bent, lunati forged rods/pistons undamaged, block cracked, thrust washer disintegrated, LS1 damaged stock oil pump(what gives Rippie!), clearences and tolerances very loose(perhaps due to detonation)...for personal piece of mind, changing rocker arms, top end un damaged. Hopefully the LPE bottom end will last a bit longer :o:

Does anybody know if my cam comp 588/595 228/232 on 114
will be same, more or less loppy idle? CR will still be 10.8:1.

Stay tuned for updates! :crazy: