[CNC BLOCKS N/E]

Do they make such a thing for a Small Block Chevy ??

I guess you have never dealt with Dart Cam bearings all their cam bearings are grooved with 3 holes. These have been out for many years.

 

[BillK]

I guess you have never dealt with Dart Cam bearings all their cam bearings are grooved with 3 holes. These have been out for many years.

I didn't think this was a Dart block. Did not realize that their bearings have three holes. Not sure why someone would want to use them in a stock block anyway.

 

[Kyleh24]

I didn't think this was a Dart block. Did not realize that their bearings have three holes. Not sure why someone would want to use them in a stock block anyway.

I wonder if he could be on to something with the cam bearings. This is a brand new block that Blueprint Engines manufactures (it isn’t a GM 400 block). I know it has some non stock features. It has priority main oiling, 4 bolt main splayed caps, and a 1 piece rear main. I have a message into Blueprint so we’ll see.

 

[gnicholson]

My 406 sbc with a high pressure oil pump I get 85 psi in you start it the engine cold. 25 psi at operating temp. Cruising around I get 60 psi. You may have a High volume, low pressure oil pump. Does numbers you gave us is for standard sbc.

the only difference between pumps of the same volume pressure wise is the spring installed. and whether the valve opened at 50 or 70 lbs would have nothing to do with idle oil pressure where the valve is closed . besides cam bearings as a possible problem what lifters are you running?

 

[Kyleh24]

the only difference between pumps of the same volume pressure wise is the spring installed. and whether the valve opened at 50 or 70 lbs would have nothing to do with idle oil pressure where the valve is closed . besides cam bearings as a possible problem what lifters are you running?

It has roller lifters. I don’t know what brand the lifters are. Blueprint manufactures a lot of stuff in house so I’m betting the lifters are their own brand. It’s a full roller engine (hydraulic roller cam and roller rockers). There might be a very, very subtle tick that I hear at idle or light throttle. I think that is probably just the roller rockers. Most people probably wouldn’t hear it, but I’m sensitive to that stuff. Haha.

 

[CNC BLOCKS N/E]

I didn't think this was a Dart block. Did not realize that their bearings have three holes. Not sure why someone would want to use them in a stock block anyway.

Once again I have worked on the Blue Print blocks they use a 2 inch cam tunnel the same size as Dart uses and that style cam bearing will work in the Blue print blocks as well as Bowtie blocks. BELIEVE ME. Durbond offers that same bearing as Dart its DT-1T

I guess I see a few more performance blocks then you do. LOL

 

[BillK]

I guess I see a few more performance blocks then you do. LOL

Considering that is all you work on I guess that would make sense now wouldn't it . . . . . . . . Sort of like a Subaru tech telling someone he sees more Subarus. Jeeeze.

 

[Kyleh24]

I heard back from Blueprint so I thought I’d share what they said: “these are a High volume, not high pressure oil pump. Basic rule is 10 psi of oil pressure per 1000 rpm, So this is pretty normal. As far as the repair I would like them to call us when they get ready to do the repair so we can tell them what to watch for.”

The 2nd part is referring to the oil consumption issue. I figured that’s what they would say about the oil pressure.

 

[blue_69_malibu]

Blueprint is not exactly known as the highest quality, custom builder. Then again, they charge accordingly....which is fine. At least they appear to be responsive to you.

That said, your idle oil pressure is too low to accept, IMHO. When a "professional" rebuilds the motor, I wouldn't accept less than 25 PSI at warm idle. Your pressure typically decreases as your engine ages.....and with only 16 at idle now, you can't afford to drop any more.

I wouldn't be too thrilled with 20, yet alone 16, at warm idle for a new motor.

 

[JF74chevelle]

Built my engine in my garage alone when I was 18. Didn’t really know what I was doing. used this site, YouTube and google to build it and it runs great. 350 with 30 PSI hot idle and 60 PSI at cruise hot. Used a standard Melling basic replacement oil pump too.

 

[Kyleh24]

Blueprint is not exactly known as the highest quality, custom builder. Then again, they charge accordingly....which is fine. At least they appear to be responsive to you.

That said, your idle oil pressure is too low to accept, IMHO. When a "professional" rebuilds the motor, I wouldn't accept less than 25 PSI at warm idle. Your pressure typically decreases as your engine ages.....and with only 16 at idle now, you can't afford to drop any more.

I wouldn't be too thrilled with 20, yet alone 16, at warm idle for a new motor.

Yeah, I agree with everything you said. The customer service at Blueprint has been really good. The engine makes great power, but quality control could be suspect. I’m not sure what the best strategy is to get them to fix this under warranty. The oil pressure just concerns me with the longevity of the engine. It seems like the oil pressure is a little lower than when the engine was first installed. That part also concerns me. The previous engine I had was a 383 and it had around 25 PSI at hot idle.

 

[p40]

that oil press is way to low for a hi volume pump , iv got a 383 with a hi volume pump its 60 psi cold and 40 warm , like stated before the press is to low and i would not accept that .

 

[Rich-L79]

Was 10w-30 oil what BP recommended?

 

[Kyleh24]

Was 10w-30 oil what BP recommended?

Yeah, I am using the exact oil that they recommend. They make it and sell it on Summit. 10w-30 usually works well on a SBC.

 

[Kyleh24]

that oil press is way to low for a hi volume pump , iv got a 383 with a hi volume pump its 60 psi cold and 40 warm , like stated before the press is to low and i would not accept that .

I would be very happy with those numbers, haha. 15 to 16 PSI hot idle just makes me uncomfortable.

 

[gnicholson]

so they told you it has a hv not a high pressure pump. like i said earlier the only difference is the relief valve spring and has nothing to do with idle oil pressure because regardless of which spring you use the the pump output is to low at idle hot to open the valve. a high volume pump will increase pressure. more volume equals more pressure. the fact that its that low even with a high volume pump mean there is excessive leakage. the most likely cause is loose bearing clearance or an internal leak like the cam bearing scenario. I had a sbc with low idle pressure that ended up being mechanical roller lifters with a higher flow oiling option for circle track racing but thats just an example.

 

[Kyleh24]

so they told you it has a hv not a high pressure pump. like i said earlier the only difference is the relief valve spring and has nothing to do with idle oil pressure because regardless of which spring you use the the pump output is to low at idle hot to open the valve. a high volume pump will increase pressure. more volume equals more pressure. the fact that its that low even with a high volume pump mean there is excessive leakage. the most likely cause is loose bearing clearance or an internal leak like the cam bearing scenario. I had a sbc with low idle pressure that ended up being mechanical roller lifters with a higher flow oiling option for circle track racing but thats just an example.

When I asked if it’s possible that it was built on the loose side, here is the response: Its possible but not likely. Most of these type engine we build have this oil pressure. Where you are at you could easily run a 15w40 or even a 20w 50 oil if you are concerned, But with a 30 w oil this is pretty normal. (( high oil pressure robs horse power, ))

 

[200170]

Thanks for all of the responses! Most small block chevys that I’ve seen typically have had a hot idle oil pressure of around 20 to 25 PSI with a standard pump. That’s why I thought it was a good idea to get some input on this. Blueprint doesn’t seem that concerned with it. They do think that it is sucking oil in through the intake rocker arm studs. That has nothing to do with the oil pressure, but it does correlate with oil consumption. I sent them some borescope pictures where you can see the intake valves have wet oil on them.

Am I missing something here but Chevy SBC heads rocker studs go into water jackets and not intake or exhaust runners. Different heads might, maybe someone can comment. If they leak they leak water into the oil and can be seen as milky oil around the stud. I once did have my intake (after market aluminum) suck in oil due to a bad gasket and or machining but I changed both the intake and gasket to resolve. Head milling can cause a angle issue for sure that can aggravate this issue. That would not cause low oil pressure as you mention. I'm running about 25 lbs at hot idle (750 rpm)with my 68 327 large journal polished crank with standard bearings with a Mellings high volume pump using factory mechanical gauge for readings.

 

[1975TypeS-3]

Heavy weight casting SBC heads the studs go into a water jacket. On the light weight (oxy-moron) heads introduced in the mid 1970's the stud goes into the intake port. 882's were the first light weight castings, 624's are more common and even lighter than the 882's.

 

[BillK]

Heavy weight casting SBC heads the studs go into a water jacket. On the light weight (oxy-moron) heads introduced in the mid 1970's the stud goes into the intake port. 882's were the first light weight castings, 624's are more common and even lighter than the 882's.

Vortec heads too