wrd1972

I am building a 355 with LE2 head and LE1.5 cam that will rev to 6.4K.
Main bearing clearances are .002" and rod bearing clearances are .0025".
Rod end-play clearances are .020", a tad larger than GM spec.

At what point should one install the GM white spring (3848911 ) into a stock volume oil pump. A lot has been said about bearing clearances but I dont know if my setup warrants this. I am at the point where I can still make this change but the door is closing.

Thoughts?

shoebox

I am not an oil pressure expert, but I don't know why you would not want to use it. It's not like that spring makes the pressure sky high and if the engine is goiing to spend more time at high RPMs, I think the higher pressure would help keep it from trouble.

seawolf06

It doesn't increase pressure, it just allows the pressure to build to a higher level before it bypasses it off. Correct?

You should use it on almost any application.

shoebox

Well, the oil pressure gauge is going to read higher. What does that mean to you?

wrd1972

Just ordered the spring from the dealer, it will go in my new Melling select 10553 standard flow oil pump as soon as I get the pickup welded on.

I assume that if the pressure were higher than desired you could run thinner oil, right?

Bersaglieri

How do you change the spring? How much does it increase it?

-Dustin-

wrd1972

You have to remove the cast cap on the oil pump where the tube sticks in. Then drive out a roll pin then the spring comes out. It is easy to once you are at the oil pump. The thing costs less than $3.00 at the dealer.

Maybe someone will chime in on the gains.

seawolf06

I read somewhere the melling select pumps have a bolt instead of a little push pin, but I'm not sure. Does yours still have the pin?

wrd1972

It was a pin I pulled out this morning.

mdacton

the mellings select i think doe have a bolt.....the regular mellings don't
I just got a blueprinted pump today.....

some people used to put a washer in there in front of the spring...it good insurance so for $3 why not right?
good luck

Dan Parker '96

Stock pump is good to 7K rpm for many thousands of miles. No need for an "upgrade".

Westlotorn

What pressure is the White Spring supposed to give you, what increase should you expect. It would be good to know before installing it. Too high of pressure is a waste of horsepower. In an engine that will redline at less than 7,000 RPM you would never need more than 60 to 70 pounds of pressure. You are going to have leakage around the Rods and that will lower the pressure some. A high volume pump might be more what you need to keep your pressure up since the rods are slightly loose.

shoebox

It's advertised at about 70 psi.

wrd1972

I cant run a high volume pump without an aftermarket oil pan replacement. There are no aftermarket oil pans that will work with my AS&M headers, the driver side routes the same way as the stock manifold.

shoebox

You don't need a high volume pump, IMHO. You'll be fine.