2004 z06 tsp 427 ls3 shortblock losing oil pressure
06-26-2023, 01:33 PM
#1
2004 z06 tsp 427 ls3 shortblock losing oil pressure Been struggling trying to find out why I’m loosing oil pressure on load at wot. Brand new tsp shortblock 10296 oil pump 2004 z06 with batwing pan. Improved racing barbell plug, improved racing trap doors, improved racing 4 stroke c5 windage tray. Johnson 2116 lifters Tfs 225 genx heads.
Cold start idle ~70psi ~40psi hot HR2 oil 10w30
6.1quarts
cruise pressure rises 10psi per 1000 rpm.
free rev and hold in neutral 73psi and holds.
checked pick up clearance was 3/16” now 7/16 to 1/2” same issue.
wot 3rd gear from 2000rpm roll 65psi by 3800rpm then starts to drop. 53psi by 5000rpm and 43psi from 6000-6400rpm then let off.
Cold start idle ~70psi ~40psi hot HR2 oil 10w30
6.1quarts
cruise pressure rises 10psi per 1000 rpm.
free rev and hold in neutral 73psi and holds.
checked pick up clearance was 3/16” now 7/16 to 1/2” same issue.
wot 3rd gear from 2000rpm roll 65psi by 3800rpm then starts to drop. 53psi by 5000rpm and 43psi from 6000-6400rpm then let off.
06-27-2023, 08:11 AM
#2
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Been struggling trying to find out why I’m loosing oil pressure on load at wot. Brand new tsp shortblock 10296 oil pump 2004 z06 with batwing pan. Improved racing barbell plug, improved racing trap doors, improved racing 4 stroke c5 windage tray. Johnson 2116 lifters Tfs 225 genx heads.
Cold start idle ~70psi ~40psi hot HR2 oil 10w30
6.1quarts
cruise pressure rises 10psi per 1000 rpm.
free rev and hold in neutral 73psi and holds.
checked pick up clearance was 3/16” now 7/16 to 1/2” same issue.
wot 3rd gear from 2000rpm roll 65psi by 3800rpm then starts to drop. 53psi by 5000rpm and 43psi from 6000-6400rpm then let off.
Cold start idle ~70psi ~40psi hot HR2 oil 10w30
6.1quarts
cruise pressure rises 10psi per 1000 rpm.
free rev and hold in neutral 73psi and holds.
checked pick up clearance was 3/16” now 7/16 to 1/2” same issue.
wot 3rd gear from 2000rpm roll 65psi by 3800rpm then starts to drop. 53psi by 5000rpm and 43psi from 6000-6400rpm then let off.
When you let off, does oil pressure jump back up? If you go to WOT then hold at 6k briefly without accelerating further, does pressure come back up? It sounds like it might be oil starvation during acceleration, but this will help verify.
06-27-2023, 08:51 AM
#3
Oil temp are 224-230 when I have tried any 3rd gear pulls. And as soon as I left off oil pressure jumps back up. I haven’t tried holding it to 6000rpm don’t want to risk it. When I trend rpm and oil pressure in datalog you can see exactly what’s happening it matches how rpm climbs gradually until about 4000rpm then it starts to drop oppositely and flatline once it’s around 43psi around 6000rpm. I have a ported standard volume slp oil pump on my old ls6 longblock with about 10000miles on it I can also swap in and try. This coming weekend going to pull baffles out. And might try a slight amount less of oil. Also to mention I have .120” pushrods I don’t know if they would be less restrictive this has yella Terra pro shaft rockers for Tfs heads on it. Johnson 2116 link bars no axle oiling. Just pumping too much oil up top quickly for it to drain back quick and enough. Or cavitating pump from a too much windage not sure. I have ran driven break in for about 600miles and now going to run this 10w30 hr2 conventional for another 1000miles. Then swap to ls30 5w30 conventional. When I drop pan I’m also going to compare pickup tube to my old long block but it looked pretty much identical where it was.