Alright, I have a 95 LT1, 385 stroker motor goin in. AI heads and intake, about 43X RWHP per sey. Probably set the rev limiter somewhere around 6300 maybe? Anyway, I thought I decided on the m55A oil pump, stock volume, high pressure unit. But, it is only a 5/8" pickup tube. The M155 is a stock volume, stock pressure, but with a 3/4" pickup tube. Which is better? This will have the canton 15-242T oil pan, and will be a daily driver, with occasional track use, but not very much. (weak stock 10 bolt still installed) I am sure I will run her hard occasionally, but not alot like a drag only car. I have heard that HV pumps are mainly for big blocks, or motors with very slopy bearings. If I am wrong, please correct me! But, what are you guys running? Any recomendations? I am a newb at motor building, but I am learning as I go!
Thanks!
Cody

 

I've never really had a preference in pump pickup tube diameter. I use the M55A's as they come without issue.

Bret

 

ok, good to know. Thanks for the input, as I was lookin for people who actually use one part or another, instead of "theorists" who don't know jack! Thanks!

 

I have a stock replacement (GM) oil pump with the 3/4" bore and a shimmed stock spring, I should be firing it up within a week.

 

hmm... well, jeff creech said he uses the m55a in his car, so that must be good for something!

 

6300 rpm and 435 rwhp?

 

I use the melling standard pump with a 3/4" inlet tube. It shows 60-65 psi at cold idle, as soon as I get the car back and do some driving I'll report the rest.

 

port efficentcy! lol. Well, when its back together I guess Ill dyno it, and until then, its all "calculated"

 

GM changed the inlet from 5/8" to 3/4" during the 1994 model year. That should tell you something.

 

grr, I finaly decide on something, and then someone throws a monkey wrench into it... well crap, now what?