luvemfast Posted January 9, 2012 Posted January 9, 2012 On the new Race motor, the oil pressure is VERY low at idle. To the point of the warning lights coming on, under 15psi. I'm running the turbo pump, it's is meant to be higher volume. I can recall reading somewhere that you can shim a spring and that alone, increases the pressure. I've done a search, but can't find it. Any help? Quote
luvemfast Posted January 9, 2012 Author Posted January 9, 2012 Well, Peter has informed me that the shimming of the spring only increases the peak pressure. The spring is part of the oil pressure relief. The main issue is I'm used to stock engines. And this one is far from that. Peter has suggested that I increase the idle closer to 1,000rpm and connect an actual pressure gauge and see where that takes us. Quote
dazzed Posted January 9, 2012 Posted January 9, 2012 Well, Peter has informed me that the shimming of the spring only increases the peak pressure. The spring is part of the oil pressure relief. The main issue is I'm used to stock engines. And this one is far from that. Peter has suggested that I increase the idle closer to 1,000rpm and connect an actual pressure gauge and see where that takes us. Peters very right, but it dont matter stock or race engine engine is still turning the same rpm, was the oil system primed and checked for presure prior to starting it, oil light only means 1 thing, no pressure, or the tolerances have somehow become greater than they were when the engine was built, keep us informed, fingers crossed its a lazy oil light switch Quote
luvemfast Posted January 10, 2012 Author Posted January 10, 2012 What oil grade are you using Simon? Penrite HPR30 20-50W It's more than likely to be my sender and low idle. But I don't know about you, but my life does not revolve around my Z. I have other things to do, so my time in the garage is scarce. Quote
luvemfast Posted January 12, 2012 Author Posted January 12, 2012 Ok, I've been out in the garage tonight. I've lifted the idle from 750rpm to 950rpm. It's not so simple when you have triples, as you have to sync them and then recheck the idle screw settings. But, the difference was huge and Peter Mac was 100% correct about how to rectify the issue. 200rpm made such a difference. The pressure is now sitting on 2kg/cm2, which is about 28psi. Then at revs, it goes up to 5kg/cm2. Which is about 70psi. Quote
dat2kman Posted January 12, 2012 Posted January 12, 2012 Built motor? What are the bearing clearances? You can stack approx 4 mm of easiest behind the spring in the bottom of the oil pump, all this does is increase the pressure required to open the relief valve circuit. Other option is the Nismo comp double spring setup, in place of the single spring.. Also, grab a bottle or two of Joe Gibbs break in or XP4 oil, it is very high in zinc, ignore warnings, as current HPR 30 has had most of the zinc removed, to keep EPA happy. Other oils are LAT or Brad Penn, but get tje mineral version, not the synthetic version/model. Our "old"style engines need the lubricity that zinc supplies, especially cam lobe to rocker ! Quote
peter mc Posted January 12, 2012 Posted January 12, 2012 yer that's what it should be Simon 30 at 1000 and 70 at the top that's what Roberto's was and the last 4 before it , 2.8 Th is the Clarence on the bigends and this does lower the oil pres at idle but at 7500 rpm its got heaps of oil Quote
Ben Posted January 26, 2012 Posted January 26, 2012 Don't trust an electrical sender - especially an old one. Put a mechanical gauge on it & get the real measurement. I've been told that 10psi per 1000rpm is a good thing. Quote
peter mc Posted January 26, 2012 Posted January 26, 2012 Well he did today and the sender was at not good. With the gage and the engine at temp it had 30psi at 1000 rpm and 68 psi at 4000 so don't trust old gages . Quote
PZG302 Posted January 26, 2012 Posted January 26, 2012 Yep as long as my old.gauge moved I was happy. Warming up it showed close to the true pressure on the gauge. Coming off.the track after a race the gauge showed alarmingly low, but I only ever trusted the warning light I had fitted. Quote
dat2kman Posted January 26, 2012 Posted January 26, 2012 The little tiny weeny, hard to see in a heated intense situation, red low pressure warning lamp buried down in the instrument cluster, goes off at around 8 to 10 psi of pressure, on start up. In a lets say race stuation, you are cornaring and acceleratiing, the head valve train is full of oil, the sump is lowish, oil has shifted away from the pickup, you are concentrating on the view out the windscreen,,,,,, you wont see the little weeny tiny 8 psi low limit light flash on! Fit a higher say 20 psi sender, a top of dash mounted hi intensity red led mini lamp, aimed at your eyes, youll crap yourself at how often it may flash. Only thing NOT. To do is hang a T piece brass adaptor off side of block, to fit both senders, use a couple of push on hi press barb fittings, and hose, and remote mount the tee on inner guard, earth the tee! Block harmonics can fracture the tee where it screws into the block, ,, think about all the weight of the two senders attached, same goes for those that use a tee for light sender switch, and oil pressure guage. I have had two snap off at the pissy tiny 1/8 th npt thread where it goes into block. Quote
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