SBC 0il pumps

[Little Mouse]

For a higher rpm street engine with loosened up clearances would a melling M99hvs bbc standard volume oil pump with its 12 teeth be an advantage to using the 7 tooth SBC pumps in quality of oil flow or would using melling new SBC shark tooth pump be the way to go.

[Tom68]

One of the strongest points of a SBC (and it's got plenty) is the oil pump they can handle almost anything with just the addition of a 60lb spring. At least that was true in the days of 20W 50.

[1980RS]

I just use the stock Melling pump as after I saw how much it took to drive the HV pump and figured out I don't need it.

[mt-engines]

Melling M155 is what I've used a bunch for 7000+rpm street small blocks. It takes a .750 pickup

[novafornow]

My ST is a 3/4" tube as well. I will say that I don't believe that anyone who has installed a ST pump regrets doing it. Very smooth pump.

[af2]

For a higher rpm street engine with loosened up clearances would a melling M99hvs bbc standard volume oil pump with its 12 teeth be an advantage to using the 7 tooth SBC pumps in quality of oil flow or would using melling new SBC shark tooth pump be the way to go.

People have different opinions. I like the BB pump with a standard spring in the SBC engines that see 8500 plus. As with mine never had a failure and the pressure was stable with .003" clearance. And the fact you don't have to spend a gazillion dollars for good oiling.

[ClassAct]

I just use the stock Melling pump as after I saw how much it took to drive the HV pump and figured out I don't need it.

What was the HP difference?

[RDY4WAR]

How loose of clearance are we talking about?

[Schurkey]

I just use the stock Melling pump as after I saw how much it took to drive the HV pump and figured out I don't need it.

WHICH "HV" pump? Melling makes several for the SBC.

From the little info available, the big-block design takes less horsepower than the extended "straight" gear small-block designs. But I've never confirmed this with my own testing. And I have no idea about the newer helical-gear "shark tooth" design.

My next small-block engine is getting the big-block pump.

[Little Mouse]

How loose of clearance are we talking about?

I'm going to be using an eagle crank 3.25 stroke, I'm thinking .003 on the mains and at least .0025 on the rods, want it to make power to 8000 rpm. I have not bought heads and pistons but I'm considering using 49 cc chamber dart iron eagle with inverted 12cc dome pistons.

[RDY4WAR]

How loose of clearance are we talking about?

I'm going to be using an eagle crank 3.25 stroke, I'm thinking .003 on the mains and at least .0025 on the rods, want it to make power to 8000 rpm. I have not bought heads and pistons but I'm considering using 49 cc chamber dart iron eagle with inverted dome pistons.

I would use a Melling M55HV. The clearances would be fine with a standard pump, it's the RPM that will want the HV pump.

Your clearances are fine. I would aim for .0012" per 1" journal diameter for something like that which isn't far off from what you have there.

The oil for that needs to have a high temp, high shear (HTHS) rating of ≥3.5 cP in a 5W-30 or 5W-40. I would also recommend a higher end synthetic and streetable race oil that'll have the boosted anti-aeration and anti-foaming additive content, as well as boosted friction modifier content, to help it out at high rpm. Red Line HP 5W-30/40, Amsoil Dominator 10W-30, and HPL Bad Ass 5W-30/40 would be good choices.

[Little Mouse]

I'm somewhat sold on using amsoil for oil. It seems like a 12 tooth pump over a 7 tooth would be a better way to do something over extending the length on a 7 tooth. The bbc pump may cause a little pan fitment problem. I do like the pumps melling came out with a few years back where they have the gears seated both top and bottom and have a 3/4 pickup tube. I'm not sure about the shark tooth version of it what it's advantage or disadvantages might be.

[ClassAct]

How loose of clearance are we talking about?

I'm going to be using an eagle crank 3.25 stroke, I'm thinking .003 on the mains and at least .0025 on the rods, want it to make power to 8000 rpm. I have not bought heads and pistons but I'm considering using 49 cc chamber dart iron eagle with inverted dome pistons.

I would use a Melling M55HV. The clearances would be fine with a standard pump, it's the RPM that will want the HV pump.

Your clearances are fine. I would aim for .0012" per 1" journal diameter for something like that which isn't far off from what you have there.

The oil for that needs to have a high temp, high shear (HTHS) rating of ≥3.5 cP in a 5W-30 or 5W-40. I would also recommend a higher end synthetic and streetable race oil that'll have the boosted anti-aeration and anti-foaming additive content, as well as boosted friction modifier content, to help it out at high rpm. Red Line HP 5W-30/40, Amsoil Dominator 10W-30, and HPL Bad Ass 5W-30/40 would be good choices.

Just curious…why the .0012 per inch? It seems currently the trend is .0009 or even .0008 per inch. Is it the RPM or something else ??

TIA

[amc fan]

If I remember correctly the small block standard oil pump flows more oil than a standard big block pump.
The advantage of the big block pump is it has more teeth on the gears, and it runs smoother, less spark scatter.

[Little Mouse]

I think in olden days before all the high volume sbc pumps the bbc chevy pumps got used on sbc because they pumped more not less and the bbc guys bought even higher flow L88 bbc pumps for there bbc.