TT427

iTrader: (1)

I'm interested in this, bought the 296 pump a few days ago. Figured with the turbo and a cooler it couldn't hurt to have the extra volume. I Plan on drilling the lifter buckets out to help drain back, any thing else to help control oil with the block?

Game ova

This may sound a bit silly, but I wonder if using really tall gears would create an issue like this....when using the factory pan. I'm thinking using a tall gear would keep the motor rpm high at the end of 2nd and high....pulling heavy on the oil in those two gears. I'm running 2:73 myself and can go through the traps in 2nd and can definitely tell if spend a lot of time in 2nd going through the quarter. Just a thought.

tblentrprz

Thanks Rich. Not sure why factory cams seem to not induce cam bearing failure/spin or walking out. Is it a function of not seeing 6500rpm or aftermarket cam journels slightly larger causing clearance too small and potential oiling issue. Seems many pin them to eliminate the potential for failure. As always, curious of root cause and ultimately correct resolution.

TT427

iTrader: (1)

Extended high rpm seems to be a common denominator in most of the "sucked dry" ramblings. Supposedly an extra half quart should help remedy the problem. I find it funny so many tuners use the 296 pump and few issues. Also wondering how 4th gen drain back might differ with dod and the higher flowing pump. Are their pans bigger?

BlkLT1Z281

iTrader: (1)

And you still think the oil pump was the problem? The cam bearing walking out caused your lack of oil pressure, not a HV pump sucking your pan dry. This would have happened with a standard volume or stock pump.

SPRAYED 01

iTrader: (22)

I called mellings to discuss. I'll start by saying I understand he sells them so of course he's not going to say anything bad.
With that said I just simply asked what pump he recommended. What followed were questions on exact bearing clearances, intended use, turbo size.
After he recommended the 10296 with the high pressure spring I asked about the whole pan sucking dry thing.
His response was a question. Where is all the oil going?

I really didn't have an answer other than suspended up top.

He said this is all non sense. The pump will only pump until its filled in all the places it needs to go, then you get pressure from resistance.
It's not like it's shooting oil out of a free flowing garden hose.
He also noted that it only flows 18% more then stock and that there is no way factory pumps are already at the edge of flowing too much.
He ended with telling me that there are factory gm pumps on the newer engines that flow about 20% more than the 10296.

In the end im no expert but what be says does make sense. Also why would it be that some of the biggest shops around use the pump. If it sucks pans dry wouldn't it do it to all of them?

oscs

iTrader: (19)

Do you have pictures of the porting to the pump?

roastin240

iTrader: (13)

Of the pump or the oil pan? Alot of people port the pumps, but I can show you my work once I dig up the pictures. I acquired a TSP "ported LS6 pump" second hand for free years ago and there is still alot of improvement to be made. Some dude must sit there and crank out 20 a day in order to make a profit. I port, polish, clean and shim a pump in about 1 hour, starting with a Melling OEM replacement pump. They are around $100-120 most places. Amazon is $65...super duper bargain deal. Get it before the price goes up, if it hasnt. I should probably grab a couple more just in case.

As far as porting the passages in the pan, there was little to no info on it so I started doing it and man you can free up alot through the passages. Look at the oil flow path through the oil pan ports in order to be filtered...it has to go through hell and back to get to the main oil rifle. Im not sure why others dont do this. I will post pictures for you guys when I have some time to pull them off my phone.

Could probably help some members out if they wanted me to do the porting on the pump and/or pan.

SPRAYED 01

iTrader: (22)

Im in for pictures of the pan. Mine goes all back together this weekend so I have some time to do that now. Thanks

oscs

iTrader: (19)

The pump

Nitroused383

iTrader: (10)

Denmah actually just tuned a car on the dyno that sucked the pan dry from the 10296 so he had to abort the pulls because of low oil pressure. The ls isn't new and people have had very real issues with high volume pumps for years.

kingtal0n

iTrader: (1)

Accumulators have come down in price quite a bit, i am surprised more don't just bolt on an accumulator, instead of fooling around with all these other "mods" for oil flow/return/overfill. Log oil pressure and run an accumulator with any pump you want; /problems

I dislike the torturous path oil takes to get to the "main drag" (journals), and adding a remote filter seems to make it even worse.

Nathaninwa

My ls3 block had horrible casting texture. I spent some time with my head porting tools and deburred, smoothed all the oil return areas. I also added some -10 hose from the heads to the oil pan to help shortcut the return path

I think a big issue is crank case pressure, and it holding it up in the head, that's why I added the -10 hoses. I'm running a vacuum pump and pull from the valley cover and supply fresh air to each valve cover, helping with that downward airflow

This is on a stock ported DOD pump, with dod delete and pan relief delete on a 7 quart pan setup

I also did some things to eliminate the barbell to help with increased oil flow

roastin240

iTrader: (13)

Can you provide more details and/or pictures of the pan relief as well as the barbell?

I tend to get a little obsessed with crankcase ventilation and have built multiple iterations on many platforms with some minor and great success on others. I designed and built 2 catch cans for my setup. Water jet cut the baffles, and hand TIG welded it together. It catches quite a bit. I need to put a pressure gauge off the crankcase and duct tape it to the windshield and make some pulls to see where its at.

What vacuum pump do you use? I do not want a mechanical vacuum pump, but would be very interested in an electric DC driven pump that I could either control with variable voltage or high frequency PWM using an external frequency module that increases megasquirts frequency output channel from the low 100-150 Hz up an order of magnitude to around 1000 Hz. This reduces heat rejection and is a nice way to do variable fuel pump control. It would be neat to use a pressure transducer off the valley cover as feedback to control pump speed with either of those methods I mentioned (which would control to a target crankcase pressure under all operating conditions). I just have no feel for whats available and what flow rates can be realized with one as well as what current it would draw. Anyone?

Rich Halsey

iTrader: (4)

I think the cam bearing spun from lack of oil and that caused it to walk out.
This is the 3rd engine I have had in this car. First 2 were stock pumps (with very low idle pressures) and I beat on them like they owed me money and everything looked like new when I tore them down. This one I decide to try the melling and it lasts fine driving around on the street and no high rpm running for extended periods. First couple pulls on the dyno and its a done!
Im no expert, but for me, I will not have another HV pump on my engines!

3 window

iTrader: (1)

Unless bearing clearances are opened up, I don't understand the obsession with HV pumps. Add a HV pump, chop the **** out of a factory pan to make it fit while reducing it's capacity by two quarts, don't add any additional oil (after adding oil lines to and from the turbo), go do a **** ton of high rpm burnouts and then wonder why it blew up or walked cam bearings out! Pinning cam bearings is a joke! It's not fixing the line bore problem, it's just not allowing the bearing to seize to the cam shaft or walk out of the journal (and no, that doesn't mean it's fixed). It shouldn't have to be done. If the bearings get tore up, it's lack of oil, pump cavitation or excessive heat (due to lack of oiling or improper clearnaces). I know it's a "duh" but if there's oil where there needs to be oil and it's not being overheated, there won't be a problem. Sorry for the rant.

SPRAYED 01

iTrader: (22)

Who's chopping the ls1 pan to make the hv pump fit? It goes right in.

3 window

iTrader: (1)

I wasn't referring to the LS1 pan specifically. Just generally referring to all the chopped up pans used during transplants.

69-chvl

iTrader: (11)

Can you really pump a pan dry even though all the openings in the engine have remained the same? if you have pressure, that is opposition to flow. I can't see how more pressure is doing anything for anybody unless you have more leaks to take care of (pressure fed solid lifters for instance)

Game ova

HV pump here.....no issues whatsoever. Rock solid pressure at all times.