You'll have a few more lbs of pressure in the low RPMs

 

How? If the bypass spring is set to open at, say 60 psi, how is it going to have any impact when your oil pressure is only at 15lbs? I would expect that a high volume pump would potentially create more pressure at all rpms due to the extra volume being pushed through the same restriction, but I can't see a high pressure pump proving more pressure under any conditions where the maximum pressure isn't reached.

 

I have always read that high pressure costs horsepower. Seems like I saw a study in Hot Rod Mag that referenced 10hp or more due to high volume (read high pressure) oil pumps. Just my 2 cents.

 

High volume is not the same as high pressure

Shim it or dont, it wont hurt anything

 

Yeah, high volume pumps, as well as high pressure pumps (NOT the same thing), both cost horsepower, though I have no idea how much. In both cases, you have a higher restriction that the crank must overcome. The high pressure pump should only rob horsepower at high rpm where it's got more fluid to push through the motor due to less being bypassed. With the high volume pump you're pushing a higher volume at all rpm, so your higher parasitic losses are present at all rpm. I have no idea what the losses would be, but I suppose 10hp sounds reasonable at high rpm in some cases. I would expect though that in most cases it would be less.

 

i'm running a shimmed/ported ls6 pump. 50lbs idle cold, 40lbs idle hot, 80lbs wot going down the race track.

 

I'm running stock untouch LS6 pump. I have about 35PSI HOT idle. 50ish cruising on the highway and Pegged at 60 at WOT. M1 5w-30 and 65-70K on my shortblock.

 

My stock replacement melling performs like yours

 

Matt, this question is for you too!

Mkos, is your shortblock a stock shortblock, or has it been rebuilt? Lingenfelter made a comment on 'tech that they prefer a high volume pump with rebuilt/aftermarket rotating assemblies because of the camfered bearings, which allow for more oil leakage. On the other hand, TSP seems to run ported LS6 pumps on all of their stroker builds, so who the hell knows.

 

mine is a pro-line assembled shortblock, it is not stock. my rods are setup at .0023-.0026 and my mains are .0021-.0023 with H-series bearings. iron 6.0 block, stock gm crank, ground .010 on the rods and .020 on the mains. i'm running eagle h-beams, and have kept it on a mobile 1 10w30 diet, though i've aquired some cases of brad penn 10w30 and am considering using it for next season.

i picked up my pump used actually. it's a TSP ported ls6 pump. i inspected it when i recieved it and it chekced out within factory tolerances, so i used it.

i drove the car to the parts store this morning, maintained 60+psi cruising. i'm using a mechanical gauge to monitor and i'm pulling from a modded adapter above the oil filter.

 

Mines a bonestock LQ4 shortblock with the ONLY upgrade being Katech rodbolts. Funny also because my truck which is a 07 2500HDClassic with the LQ4 has the same oil pressure charicteristics lol

 

Thanks guys. I'm still debating whether to port this POS LS6 pump, clean & port one of my other pumps, or cough up the money for a Melling just for piece of mind.

Now I'm also considering a chain dampener. Having a case of the "while I'm at its" is like pushing a snowball down Mt. Everest.

 

In the last 3 weeks I decided to port one of my old pumps and go with that. I'm going to sell or return my new pump.

Here are a couple pics of the port job, along with my re-assembly, and bolting it onto the motor:






And bolted onto the motor:


Next I need to get some washers so I can shim my windage tray, and then I can mount my oil pickup, my front & rear covers and my oil pan.

 

great progress jim! the port job looks great

 

Thanks. It took me forever! I didn't have my air compressor set up yet, so I did that with a dremmel, followed up by a lot of hand work with sand paper! I didn't get extreme with it, especially on the intake side because it just seemed completely unnecessary. I see some guys hog out the intake side, but if you put the pickup tube in there, it brings to light just how unnecessary most of that porting becomes.

I ported my other used pump too. I may throw it up in the classifieds.

 

I made a little bit of progress today. I test fit my windage tray, and in the process, realized that I never got an f-body windage tray, and also learned that the truck windage tray doesn't fit without some modification.

Here's a shot of the washers I used to raise the windage tray away from the stroker rotating assembly:


Here's a shot of the interference between the oil pickup mount and the windage tray:


I also discovered that the front of the windage tray prevents the pickup tube from seating into the oil pump properly. A quick search through my available literature revealed that the f-body windage tray is very different than the truck style:


So, I did what any self-respecting ******* would do. I cut up my truck windage tray:


I cut the front of the tray off, and I cut a clearance hole around the oil pickup mount:


Like a glove!




A little final clearancing and it's got room all around:


I'm going to look around and see if I can get an f-body tray and how much it costs, but I really can't see any reason why this won't work. Having a little oil splash around out of the area that I cut really shouldn't have any noticeable impact on, well, anything. Anybody agree/disagree?

 

Im sure it will work but the truck trays have more windows in them and the pans are MUCH deeper so I would worry that might be an issue. Certainly nothing ten minutes and a quick mig welding wont solve with a few patches but I think id at least weld it up to match. Then id run it why buy another?

 

I don't even have a welder. I'll find an f-body pan before I screw with welding this one.

 

this thing should haul. i hope you have a decent tire/rim combo for it

 

Well id bet it would be okay as is but the thing is... after all this work and $$$ to build it this cherry, is it worth risking harm for a windage tray? 7000 RPM comes up mighty quick with these suckers

 

I can't see your cutout causing any grief, but only having a few threads to bolt down your pickup tube seems concerning. Maybe it is just the picture and will be fine once it has been torqued down.

Have you checked clearance between your pickup tube and the pan bottom? I would check it with that many washers on the studs.

 

Dealer can get the tray for about $20 if it bothers you

I wouldnt hesitate to run that. If it clears, no worries

 

i see zero issues with that tray now that you've modified it.

 

I didn't realize that the dealer could still get the tray. It seems like everything else f-body related was long discontinued. If I knew I could have still gotten it for $20, I wouldn't have bothered screwing with this one!

 

I ordered a brand new pan/windage/pickup from the dealer i used to work at with my employee discount and it was like $250. The demand for the pans is still there so they make them

 

Yeah, I should have done more homework for my oil pan. I think I paid $200 used for mine, plus I had to buy a new gasket, and now apparently a new windage tray. Oops.

 

Well, I ordered the f-body windage tray yesterday, so it should be here next week. In the meantime, I got all of the parts I need to put my snowmobile back together, so I'll be working on that. I need that out of my garage so I can get the GTA in. Once that's in, I can pull the drivetrain out and start prepping the car to get the drivetrain that's coming out of the IROC.

 

Update. I took pics a while ago, but haven't had a chance to upload them.

The windage tray came in, and I got everything installed and started to check the pickup tube's height compared to the oil pan. I was about ready to button up everything and found a thread on 'tech discussing the older oil pumps and how they were considered to be inferior. Of course, everybody perpetuates this, but nobody seems to know WHY they are inferior. In any case, I got curious and ripped mine back off the motor and discovered that mine has a 97 date stamp. Even though I can't see anything different about it, I got nervous and finally decided to buy something else.

My new Melling 10296 high volume oil pump came in yesterday. This thing is a thing of beauty. Made in US and A. I opened it up last night and unlike the Mexican stock "LS6" pump, this thing looks great inside. It's a very high quality casting, and the machine work looks first rate as well. I'm going to port the pump, put it back together, and stick it on the motor.

Pics to follow.

 

The old 97/8 pumps would work fine or simply fail. It was very random but it was a very real problem. Money well spent on a new one imo

 

I don't doubt that it's a real situation, I just wish somebody could point me to why that is. After going inside of a 97 pump, a 2003 pump, and a 2011 pump, I really can't see ANY differences. They're all the same visually.

 

If I had to guess Id say it was a casting issue. This was the first time GM had used most of these alloys and there was a LOT of small changes made to the block and cyl head process and on and on. In the first few years of LS production they pretty much tried everything and whatever worked best? Became the default for the future engines. For instance the LS6 block was the debut of the new stronger alloy that is now the standard alloy. The windage was redesigned about 3 or four times iirc on gen 3 LS engines alone. Not that there was a lot of block problems but with Katech and the C5R development program GM was successfully pushing QC up preparing for the genIV engines and more importantly the Exotic killlers like the ZO6 and the ZR1 so the oil pump was just another blip along the way.

I should note that every 97/8 oil pump failure thread I stumbled upon? The engine had less than 75k miles and most were sub 40k miles. It was a pretty quick discovery if you were one of the unfortunate ones so your pump being so old is probably ok but as Ive said before with the year/s it take to make a quality swap/build is it worth risking?

Not in my book

 

I agree, and that's why I finally bit the bullet and bought the Melling. Now I get to worry about pumping my whole oil pan into my valvetrain instead of worrying about the pump crapping out.

 

Well fwiw my new engine is VVT and runs oil pressures upwards of 90psi sometimes as its the oilk pressure that drives the cam phaser and no starvation issues here even at 7000 RPM


So I think you'll be fine just be careful with your PCV routing as it can become an oil feed on these things. In fact Id recommend a catch can

 

Yeah, I'll be running a catch can system. I also picked up the LS6 style valley cover for my PCV routing.

Word is the only time the high volume pumps become an issue is at extended high rpm runs. Texas Speed has managed to nuke a few motors running them steady at high RPM for long durations, but there don't seem to be any failures during normal usages.

 

Yeah Texas speed beat the hell out of their test mules. Extended high RPM builds are a different breed anyways Id go a totally different route if thats what I wanted. Those engines dont belong on the street though. But drag racing or even "occasional" blips over 6500 RPM for a minute or so hasnt caused me any issues with any of mine

 

pics of my progress:

First, the new Melling oil pump. Overall, this product appears to have better build quality than my old pumps, and MUCH better build quality than the new Mexican made OEM pump.
Here's a pic with the cover off:


Gears out to see the housing:


Close-up of the outlet:


Closeup of the pickup tube area:


Unlike the stock pump, I didn't feel that this pump really needed much porting. Inside the outlet tube, I didn't touch it. The Melling has a nice smooth radius, unlike the stock pump. All I did was clean up the edges a bit:


Another pic:


I just cleaned up the inlet a very slight amount just to knock the sharp edges off.

Here's the pump put back together:


Pickup tube & oil pan pics to follow.

 

Apparently we're now limited to 8 pics. Pretty soon IB will make it 1 pic per post. Anyway, 2 pics moved down to a new post. :-/

On with the show...

I bought the BRP oil pickup retainer that utilizes the extra oil pump hole in order to better clamp the pickup.


Here's a pic of the blue f-body pickup tube o-ring lubricated and ready to go:


Here's that pickup tube retainer installed. Unfortunately, this came out blurry, but it gets the point across:


I didn't show any pictures yet, but I also swapped the cut up truck windage tray for a new f-body tray. You can see it in this pic, that also shows the washers I put onto the pickup tube to check oil pan clearance. These 3 washers stacked to just about 3/8":


doesn't quite fit.


2 washers (1/4") fits, but I wanted a little more clearance, so I pounded on the pickup with a rubber adjuster (mallet), and tried again (many nights later, hence the different washer stack):


Like a glove!

 

other 2 pics from above. Nothing interesting.

While I was screwing with the old windage tray, I painted up some of my hardware, specifically the bolts for the oil pan, the front & rear covers, and the freeze plugs:

 

jim, your attention to detail is a sickness. i hope one day i can say i've been infected...

 

I'm just hoping that I can say someday that it's paid off.

 

The other night I installed my cam degree wheel, and set up my dial indicator on the piston, but quickly discovered that my old magnetic base wasn't doing the job, so yesterday I ordered a new magnetic base that should be more stable.

Last night I started pulling one of my heads back apart. After buying my camshaft, which has a little less lift than the one I had originally anticipated (.614 vs ~.650), I have to shim my valve springs about .030, so I started pulling those apart last night. I only got one spring out so that I could measure my new installed height, which came out to 1.776 with the shim installed. When you subtract the 1.060 coil bind height and the .050 safety margin, that brings your final height to .635, down from the .666 measured height I had previously. I need to re-check my measurements carefully though, because last year when I did this the first time, I measured a .674 installed height, which is .008 higher than the .666 I measured this time. Not really a big deal, but I don't like the inconsistency.

 

why are you shimming up? are you trying to get more seat pressure to control lifter bounce or something? seems that if you went with a higher lift camshaft that you'd need more seat pressure than a lower lift cam. by going up in seat pressure, are you going to risk tearing up lifters or anything?

i guess my point is: if the valve springs had enough pressure for a bigger camshaft, why would you shim the valve springs (which increases seat pressure) for a smaller camshaft?

 

People I've talked to, including Texas Speed (PRC springs are their brand) have said that with high lift cams, you want the springs installed close to coil bind in order to minimize harmonic oscillations that can lead to premature spring fatigue. It seems that these stiff springs are prone to resonance at high rpm.

 

Last night I pulled the springs back off of one of my heads in order to install the shims, but I can't re-assemble until my new valve stem seals get here. I think Texas Speed sent them by Donkey Express.

In any case, one thing that surprised me was just how inconsistent my installed spring heights are. I measured all 8 heights on this head last night, and my installed height (with .030 shim installed) ranged from a low of 1.744 to a high of 1.756, for a .012" difference. I can't seem to find any shims thinner than .015, so I guess being within +/- .007" is going to have to suffice. I may stuff a .015 under the highest spring, which will bring my range down to 1.741 - 1.753", for a max valve lift of .631 - .643. My cam has a lift of .613/.617.

 

hmm. anything wrong with just installing the springs and running it? seems like a ton of people just throw them on and go...

 

That's probably also why a "ton of people" bitch that their springs only lasted 20k miles and wind up with a trashed motor after an intake valve hangs, hits a piston, then breaks off and dances around in the combustion chamber. Based on what I've read/seen, it's preferable to shim the springs to being within .050 of coil bind at max cam lift in order to minimize oscillations that can fatigue the spring. The guys at Texas Speed didn't seem to feel it was critical, but did say that it would probably help if I threw a .030 shim in now that I'm running a lower lift cam than I originally anticipated running.

 

Makes sense Jim, I'll have to do that on mine.

 

Small update. The other day my new valve stem seals finally came in, so I decided to put that head back together since I still couldn't finish degreeing my camshaft until my dial indicator extension kit came in.

After fighting with the low quality POS valve spring compressor I borrowed from a friend, I finally got the head back together.

Today I ordered a new Procomp valve spring compressor, because I am NOT going through that again on the other head, and risking damaging a valve.

In other news, the dial indicator extension set came in today, so hopefully soon I'll finish degreeing my cam.

 

Good Lord, that motor is going to oxidize into dust before you start it up for the first time! Just givin' ya crap..

Looking good and hopefully being this meticulous will pay off

 

Well, that didn't go well.

I installed a lifter, got the dial indicator set up on my new magnetic base, and started taking measurements. I established peak lobe lift, then measured .050 down in both directions and checked the numbers on the degree wheel in both positions. I did the measurement a few times, and got consistent numbers, but then I started over, and got two completely different (but equally consistent) numbers. In both cases, the numbers averaged out to 110, indicating that my cam has a 110 degree ICL and not the 112 that it was supposed to be ground to.

After comparing the differences in my degree numbers, I discovered that the dial indicator was riding up the ramp of the lifter cup, which is probably why I got vastly different numbers both times. That said, at positions +/- .050 from peak lift, the dial indicator was pretty steadily positioned, so I'm inclined to think my 110 is correct.

I attempted to re-position the dial indicator, and in the process of snugging the fasteners on the base, I stripped the threads on my POS chinese base, so now I've got to wait another fricking week to get another base shipped to me (and this one will probably cost a bloody fortune unless I want another trash chinese one), and then after I measure it again, I'm sure that I'll find that my cam is still on a 110 ICL and not 112.