24 replies to this topic

[RallyRed]

Ok, so hopefully someone can provide some guidance here. Being in lockdown has me down in the shed playing with this LS2 we have.
I hope to learn something, with your help.

Turbo charged, built engine, all was well.
Now blowing a fair amount of blue smoke.
Did a comp. test - all around 155psi.
Did a leakdown test and it shows around 65% leakdown across all cylinders i e. awful.
Comp. and Leakdown tests both done COLD, as it has no exh. manifolds on it atm. i.e. cant run it.
Question - I read that motors built for boost have larger ring gaps, typically.
I dont have that data at hand, so can't confirm. Regardless, would that potentially give the poor leakdown readings?.
Obviously there is something wrong with it, due to the amount of smoke it's blowing.
I just wanted to get confident with the leakdown numbers , before taking the heads off, to sort out a lifter type issue.
Any advice welcomed.
Thanks
p. s. if I directly hook up an air hose ( not a leakdown rig) at say 20psi, into each cyl. at TDC in turn, and confirm the valves are closed on that cylinder, air is freely heard/ felt coming up through heads/ push rod holes.
Doesn't me feel happy.

[neglectedtorana]

Just in case its hard to determine exactly where the air is coming from can you spray soapy water in the inlet and exhaust ports to check valves

Dont know about ring gaps on boost engines sorry

 

Unfortunately the area your feeling the air from doesn't sound good but could be bigger ring gaps for boos, I remember seeing a youtube from C.O.M.E about building a boost engine and they talked about the different ring gaps in thou, worth a google

[ozyozyozy]

I doubt you would see a 65% leakage from a ring gap been a few thou larger. The fact it was blowing smoke aswell is an indicator something is wrong.
Need piston at TDC and both valves closed, then check leakage

[RallyRed]

Thanks for the replies.
99% sure valve sealing is good.
Yes, 100% sure TDC and both valves are closed.
My dummy thoughts are that the only way air can be coming up through all of the pushrod holes is if it is first getting past the rings and into the bottom ofvthe engine.
Have done the old peice of hose in the ear ( stethoscope style) and its clear that no air is escaping from the throttle body or exh. ports, only the pushrod holes ( or with the tappet covers on, from the oil filler hole.
Will do it again once new tester arrives.
Thanks again.

[dron]

If you add some oil into the cylinder in question turn over the engine by hand 2 turns of the crank and retest. The oil should seal the rings even with moderately warn engines. If it still leaks out of the bottem end I would suspect a hole in a piston. If it leaks but not out of the bottem end Valves are the problem.

[RallyRed]

Ta mate. 

[Oversteer]

What spec's was the motor built too, what rings, pistons etcetc? Very important qustion if you want to compare tests too anything, if it was built balls to the wall 1500+hp turbo motor it will be a loose breather of an engine(more so cold!), it has to be to survive abuse at that power level.

 

Sounds lke this engine has more problems than one, chewed cam and you mentioned heat....if it was a good turbo kit with thought put into heat management it should have been no hotter under bonnet than super charger.

 

Was it possibly the turbo that was causing smoke, what do the, plugs, manifold(s), IC pipes, IC, breather set-up and turbo housing(s) look like, oily ?

 

Was it run on 98 or E85 ? Power level ? Tune ? ....if it was abused on 98 would not take much to hurt it quick.

[RallyRed]

Ta mate.
Have identified a siezed lifter. Stuck in bore ( tie bar type).
Thinking it's an engine out job.

p.s. yes agree the tests need to be relative.

Edited by RallyRed, 17 August 2021 - 12:21 PM.

[yel327]

You should be able to pick up a good running VE-VF 6.0L as a bare engine quite reasonably priced. Get it up and going and rebuild the other one as time permits. Then sell the used engine. Might even find a whole Statesman.

[Oversteer]

Std L98 or LS3 with a better oil pump(you Must do pump, melling High pressure, not HV) and valve springs installed, dirty turbo set-up(at least a 900-1000hp/airflow rated with larger size exhaust A/R), fuel pump, injectors and tune will make easy safe 650whp on E85, will stretch it too on 98 with a good tune....best to install flex sensor(cheap factory conti sensor, All Gen4 ECU software understands flex tables and has pin for it) and run what you like when ever.....L98 will go close to 700whp, LS3 will go near 800 on E85 with a proper tune... unfortunate that most tuners do dirty half arsed tunes on minimum 2 or 3 tables, factory ECU is very powerful and when using upgraded software and configured and tuned properly they are damn good and safe.

 

Can give details for gun tuner in WA if anyone is interested.

[RallyRed]

in reply mate - 

 

Std L98 or LS3 with a better oil pump(you Must do pump, melling High pressure, not HV =yes ) and valve springs installed =yes, dirty turbo set-up(at least a 900-1000hp/airflow rated = yes ,with larger size exhaust A/R = yes ), fuel pump =yes, injectors =yes and tune= yes, will make easy safe 650whp on E85, will stretch it too on 98 with a good tune....best to install flex sensor = yes (cheap factory conti sensor, All Gen4 ECU software understands flex tables and has pin for it) and run what you like when ever.....L98 will go close to 700whp, LS3 will go near 800 on E85 with a proper tune... unfortunate that most tuners do dirty half arsed tunes on minimum 2 or 3 tables, factory ECU is very powerful and when using upgraded software and configured and tuned properly they are damn good and safe.

 

2 x XR6 turbos, I  forget the rwhp number, but just over 600 from memory. I do recall 1102 rwnM torque.  On 9lb wastegate springs.

 

It's my son's car. I think we are just about over it. Goes like the absolute clappers when al is well.  It's a very nice HSV GTS, reckon we will rebuild it and be happy n/a.  Let's just say the turbo experiment was fun and thrilling, but not long term.   Thanks again for the replies.

[Shiney005]

500 naturally aspirated horsepower is easily achievable from an LS3. Up near 700 if you get serious and start stroking.

[Bigfella237]

~ get serious and start stroking.

Hmm...

[Oversteer]

500 naturally aspirated horsepower is easily achievable from an LS3. Up near 700 if you get serious and start stroking.

Cam and springs will get you 515hp(Merican HP! GMPP) in a LS3, but I'd rather be blown than stroked ! 

 

A N/A motor that makes its HP in the last 500rpm is always 2nd to to the torque wave of boost and a motor that doesn't need to be revved.

[Shiney005]

I don't doubt it. I just bought a second hand 200 series Landcruiser that has been played with. Even though it weighs 2.5 tons, with 785 newton metres pushing it along it scares the crap out of some of the red light warriors. Well............... for the first 100 meters anyway.

[Bigfella237]

One day a fella named Laurie,

Came home with another damn Torrie,

By his wife he was caught, so a new Landcruiser was bought,

Happy wife, happy life, end of story!

[Shiney005]

Ha ha ha ha. Yep. She's happy. But so am I. This thing is a whole universe away from the 100 series.

[Ice]

Sik

[Ice]

Sik

Something tells me that thing would kick arse down Fish Creek Laurie 

[Shiney005]

I haven't tried out the "anti bog" switch yet. But front, centre and rear diff lockers should make it easy going over the sand dunes. Actually, wading depth would be the most critical factor at the moment Gene.

[grumpy xu1]

To me, the oil pumps can definitely be a problem, probably buy a good quality mellings & give it a good port & make sure the relief piston moves freely before you seal it up. Wouldn't be surprised if you have ringland damage which i have heard of some people having trouble there. The fastners sadly are a bit pricey for the ls engines. I think it's going to be a heads of look rather than rotating anything. Sounds also like the lifters weren't checked for bind in the bores. Or you've had an oiling issue. Tie bars should have been fine. Time to remove the engine i think mate.

[RallyRed]

Yeah thanks mate,...It's coming out for fixing, or being put on the 4 poster for a little rest.
There must be metal in there.

[RallyRed]

I did find this interesting...must be metal transfer off failed lifter/ roller that has "welded" to the cam, via friction?.
Looks like when you " build up a shaft" ready to machine it back to spec.
Or am I seeing things.

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[Shiney005]

Or it may have enough pressure to induce a cold weld. Although that process usually requires soft metals.

[S pack]

I did find this interesting...must be metal transfer off failed lifter/ roller that has "welded" to the cam, via friction?.
Looks like when you " build up a shaft" ready to machine it back to spec.
Or am I seeing things.

Kinda reminds me of a gearbox mainshaft that there cam does Col.

Edited by S pack, 22 August 2021 - 09:44 AM.