DELCOS NEW RIDE

[Holden202T]

oil pumps in better condition than most I've seen hehehe

[delcowizzid]

brandnew ecotec oil pressure releif valve spring helps

[Holden202T]

I shimmed the ecotec I had, but I also fitted an earlier housing to it as it wouldn't fit the crossmember otherwise, but it was fully gummed up that motor so not surprised if it had oil issues it got to about 60-70psi at full noise.

[immortality]

Yeah, my old VN had about 40-45psi with oil temps over 230° F using a 10w-40 oil and ecotec pressure spring

[vlad01]

Not sure what people mean by ecotec oil spring? GM catalog states same part number from VN-VY engines and all cross referenced V6 USA based buicks of the same years. I confirmed this with every V6 I have pulled apart. Same 66.3mm long spring in all of them.

I buy the ZZP oil pressure spring kit which comes with new 66.3mm genuine spring and a 2 odd mm spacer and new plunger. Bumps it up 5psi on 5W30 oil they claim so be more on 20W etc...

I got that on the VR.

[immortality]

The spring is the same length but if you put a original VN 3800 spring next to a VR spring and then a ecotec spring you will see the difference. The ecotec spring is much firmer

Also, have a look at the car manuals, the original VN's only ran about 40 psi oil pressure, VP/VR had a bit more and the ecotec has more again.

[delcowizzid]

yeah i think in the end they just said fuck it same spring for all engines when time comes for replacement LOL.i wouldnt want anymore pressure its too much allready.but i spose least theres plenty so if need be can open up a few galleries and not loose a great deal of pressure.the new one was a lot longer than the old one and much stiffer thats for sure was a 20+psi jump in idle psi from just a spring change.cant wait to get the wideband in and go for a lap .then might play with the LS coil box and see if we cant limiter it onto boost for a lol

[vlad01]

The spring is the same length but if you put a original VN 3800 spring next to a VR spring and then a ecotec spring you will see the difference. The ecotec spring is much firmer

Also, have a look at the car manuals, the original VN's only ran about 40 psi oil pressure, VP/VR had a bit more and the ecotec has more again.

I know lots of people said that too, but after buying "ecotec" springs I was disappointed to find they were the same as all the buick ones I have.

So I extensively researched into it, checking though Holden's catalogs at the dealership, same same from VN to VY.

Even bought springs thorough holden and also GM in the states as well as the ZZP oil volume kit (stock spring + spacer).

All were identical part numbers, same length, same diameter coil and same wire cross sectional area. Also tested the rating by weighting them and measuring compression. All were identical springs so its conclusive they are the same.

Also my VR manual states oil pressure is 414Kpa @ 1800 rpm max, typical at operating temp @ 1800rpm is 375Kpa. 60psi and 54.4psi retrospectively.


The only engine I can't say anything about is VN S1. I dont know what they ran, but holden catalog has same PN for them too.

But with 100% certainty VN s2 to VY all ran the exact same spring, I researched the shit out of this looking for a better spring and concluded its an urban myth like most commodore part swaps are.

However the V6 had 3 possibly 4 oil pump design changes. oil gallery diameters also changed a few times as well as the oil feed holes in the bearing shells.

Not to mention likely bearing clearance tolerance improvements over the years. block machining accuracy improved, just look at how shit most VN blocks were machined, Biggvl mentioned VNs had all sorts of tunnel alignment issues in the day. Lifter changes came about late 90s as well. Many many other factors influencing oil pressure.

VS engine have shocking oiling issues, same as early VT etc..

[immortality]

Early VN definitely had less oil pressure. Side by side the VN and ecotec spring are different. Might have to see if I still have an old one laying around.

Like Delco, fitting the ecotec spring saw my idle oil pressure increase drastically as well as operating pressure etc.

my VN manual says max regulated pressure 340kpa (49psi), minimum oil pressure at operating temp/ 1800 rpm 275kpa (40psi) spring free length 64.8mm

1991 it was 414kpa, 375kpa and 66.3mm respectively in my manual.

I'm fairly sure I've seen 3 different springs.

The ecotec also has the oil feed for the rear balance shaft bearing so that is more volume used that the Buicks never had to worry about.

[vlad01]

interesting your VN manual says 64.8mm. perhaps s1 did have a different spring?

I ended up testing something like 7 springs iirc, from mostly a bunch of early VP, one late VN, the VR, VT and VY engine as well as a few from Holden and GM and ZZP (genuine GM anyway). All identical, measured the wire diameter and everything.

From all the springs some of the old engines the springs were at most about 0.1- 0.3 shorter from age and constant compression cycles but only noticeable with the verniers.

Weighted them up and measured the compression just in case they used a different grade? or wire. yet again, all the same. Counted the wire turns, same as usual.


even had my spare parts guy at the dealer go through PN records to see if the newer "one for all" PN supersede any of the old engine springs. He said the PN was the same from VN (L27) all the way to VY and from what he could see always had been, normally there are notes of cross referenced obsolete PNs.


When I pulled my VP spring to ungraded it to the ecotec one, It was the same apart from very slight shortening. So I installed the new one anyway while I was there. Made no notable oil pressure increase.

As for the VS oil supply issues, it stems down to the dodgy core positioning when they cast the blocks verses how they jig its up for drilling, a big portion of the cores were shifted/jigged wrong and an unfortunate result was the galleries feeding the cam that go onto feeding the mains are mostly blocked by the cam bearing itself starving the mains , in turn starving the big ends. Also that ecotec have pathetically small oil galleries feeding the mains. Around 6mm! where late VP/VR have 9mm on the #1, 8mm #4 and 7.5mm for #2 and 3