racer7088

Me too!

-Joseph-

iTrader: (12)

The mellings and "LS4" pump are almost identical in gearing dimensions and design, other than the regulator spring. I've used a few of both with expected results.

Rob 's 73

Doe the Melling flow more oil than the LQ4?

Reason I am asking is that I recently put a 416 in my car with the supplied GM High volume low pressure spring pump. Cold idle oil pressure with 20/50 oil is right at 50. 200 degree idle is 31-32 and cruise is 40psi. It will go up to 50 or so at higher rpm. This weekend at the track (road course) I shifted at 4500-5000 because my oil pressure under load at 260 degree oil temps was 35 psi. The pressure would not go up with the RPMs. I only did one session because I was worried that I would be ventilating the block. If I let off the throttle the pressure would build about 3 psi at the same RPM

Main Brg Clear
1 - .0029
2 - .0027
3 - .0028
4 - .0028
5 - .0027

Rod bearing are all .0026

These are the measurements supplied by the builder. When I asked them about minimum pressure they sent me a new high volume pump saying that they may have shipped me the wrong one. They didn't but it got me off the phone I guess.

I am running a oil cooler and accusump.

Do I even need more oil pressure? I am going to switch to synthetic oil. Hopefully it won't break down as much with the heat.

Thanks for the help.

njc.corp

i got a couple of questions-

i got a customer who bought me this pump- for me to put on his ls3 engine..

part number on the box is 17801830


also does anyone have info on this pump http://leperformance.com/mellinglepb...s6oilpump.aspx

405HP_Z06

iTrader: (11)

17801830 is the GMPP part number for the LS6 pump.

njc.corp

Anything special about it-?

405HP_Z06

iTrader: (11)

Nope, nothing special.

jimmyblue

iTrader: (11)

So do you people do anything to try and enhance the
drain-back? Like when I have ported my own heads,
I've radiused the drain hole entries, hogged back some
rocker bosses and casting flash to make the oil return
as smooth as possible. From what I've seen of the
innards on my motor, it looks like drain-back is way
better than old SBCs.

If pump outruns drainback it doesn't matter how much
capacity you start with, empty is only a matter of
time.

Sales2@Texas-speed

iTrader: (5)

17801830 is GMPP's "hi volume" pump. 12586665 is GM's "LS6" pump.

85firebird

so my tuner recommended the ls4 oil pump in my 01z06 when im doing my cam install whats the opinion on that? can anyone shed some light. my car will be for street/strip use but mostly a weekend car. thanks

bhop42

iTrader: (2)

Alot of people keep getting confused with the part #s. Part #17801830 is the oil pump kit that includes the o-ring (part #12557752) and the oil pump (part #1258665). If you just order the oil pump (#1258665) you won't get an o-ring.


http://www.sdparts.com/product/17801...esEngines.aspx