:::RHMT::: Real Home Made Turbo
General Category => Forced Induction => Topic started by: CRX304 on May 09, 2010, 10:18:26 PM
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car background:
90 crx
A6 block
A6 head
fjt custom/longer length rods
Vitara pistons
ACL bearings
pm3 shimmed pump
pm3 pickup
pm3 oil pan
oil feed line restricted via ball valve and gauge to "Corky's Maximum Boost" levels.... 25psi reved
bearings were all plastigaged... .0008-.0015 (should have kick-ass oil pressure right?)
Long story short about the oil pressure.... built this block for a customer of mine... 60psi on start... 35psi after 3-4 minutes warming up.... 5psi after 6 minutes.
Action taken... replaced pump w/ one that I knew was good and I even ported and shimmed the spring in the pump... SAME FUCKING RESULTS!!!
So today we pulled the motor and suspected that a bearing went south cause when I did the pump a week ago, I saw copper flakes in the pan. To my dismay all the bearings (rod and mains) looked fine... slight break in wear, but honestly nothing to cause the issue at hand.
Where did the copper come from??? and why such low pressure?
what am I missing?
TIA
Mike
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Did you check the oil pressure sender?
The one thing you dont want to do is screw your customer by lack of lube.
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aftermarket gauge was installed and checked w/ a diff gauge... I'm at a loss here
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Did you use copper spray on the head gasket? This could easily explain the copper in the oil pan.
Do you have any idea what your oil temperature is?
What is the pressure at 3000 RPM.
Is the oil jet still present in the block since this is a non-vtec build?
The stock warning light does not come on until oil pressure drops below ~4.3 psi.
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Did you use copper spray on the head gasket? This could easily explain the copper in the oil pan.... yes... but they were flakes (not coagulated globs og C.S.)
Do you have any idea what your oil temperature is? no idea honestly but after 5 minutes couldnt be over 150
What is the pressure at 3000 RPM. ...35psi
Is the oil jet still present in the block since this is a non-vtec build?... yes... and the o-ring is good
The stock warning light does not come on until oil pressure drops below ~4.3 psi. light never came on... i made him shut it down at 5-6 psi
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35 psi at 3000 RPM?
Ouch. There is definitely a problem then.
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off topic ..you still running the LS rod mod on SOHC? O0
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someone forgot the oil jet........atleast the top end of the motor/valvetrain stayed cool.
FYI my stock bottom end A6/Y8 mini-me does 70 psi at 2500 rpms hot, 15 psi @ idle on 4000 mile oil.
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someone forgot the oil jet........atleast the top end of the motor/valvetrain stayed cool.
I wish that was the case, but his block didnt have one in it cause it previously a mini-me... and I had to put the head jet restrictor in.
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aftermarket gauge was installed and checked w/ a diff gauge... I'm at a loss here
I was getting the same crap, switched to rotella diesel 15w-40 or whatever and it's much better now. It's a piston/rod z6 with new decon'd & ported pump (no shim tho), also ported the oil galley 3mm and smoothed the exit to the filter. It had the same bearing clearances as yours using ACL's.
What's really odd is my last Z6 was stock with unknown milage, took boost like a crack whore, but the autometer gauge would drop to zero below 1500rpm. It ran like that w/o boost for several thousand miles. The gauge was stolen, then I crashed the car, so I never got a chance to test anything.
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rotella diesel oil is magical :yes:
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sorry, but i refuse to band-aid the problem w/ a thicker oil.
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35 psi at 3000 RPM?
Ouch. There is definitely a problem then.
Not really, stock specs are 30 psi @ 3000 rpm
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35 psi at 3000 RPM?
Ouch. There is definitely a problem then.
Not really, stock specs are 30 psi @ 3000 rpm
No it is not. According to Alldata, normal oil pressure is 74 psi at 3000 RPM for a D16A6. Where did you get your info?