Mr. Notorious

iTrader: (1)

Hey guys, I purchased a 383 short block that I'm building from the short block up. It is a '89 block, one piece RMS, and roller cam obv.

I'm putting in the cam and I realized I forgot to purchase a cam retainer plate. Summite only offers 2, both through GM Performance. The only difference is the bolt circle it appears. I'm obviously going to have to measure mine unless someone knows what the factory bolt circle is for the retainer plate. They just all say for a ZZ motor which confuses me... is that right? I'm surprised comp cams doesn't have one?

http://www.summitracing.com/parts/NAL-10088128/

Is there a bearing that is supposed to go between the cam and the locking plate? I assume not, but just wanted to check first.

Also, when installing new roller lifters, comp cams say not to soak them. Without soaking them, how to do you check for piston to valve clearance? Because obviously they just flatten out once you roll over the motor and you don't get the full valve travel. I have dished pistons, 64cc heads, and .051 head gasket, cam lift ~.485, rocker ratio of 1.6.

One last noob question, there isn't any gasket or o-ring that goes between the oil pump and the block right? I just worked on a Jeep 4.0L and it reminded me to ask if there was one for the SBC.

That's the only thing that sucks about building a bare block, if you don't know what came off exactly, you can easily miss something. I appreciate the help...

Apeiron

The bolt spacing changed in the later 1 piece RMS blocks, measuring would be best.

No

Disassemble a spare lifter and use washers to eliminate the plunger travel and make a solid lifter, and/or use a lightweight checking spring on the head.

No

Mr. Notorious

iTrader: (1)

Awesome response, thanks.

So since it's brand new, do they still suggest not put in brand new lifters dry? How do they expect you to set the rockers if the lifters are just going to run flat for awhile? I would imagine it would be difficult to get the TPI running decent enough to pump up the lifters in order to adjust the rockers?

Then to find the proper length pushrod, do you take a washer out of the newly made solid lifter to account for lifter preload while it's operating? Or do you assume the lifters in running condition always have the plunger all the way to the top of the lifter?

Apeiron

Set the rockers before you start it.

You can remove a washer, or you can subtract the amount of preload from the length you measure.

JakeJr

Comp says not to pump them up. Comp specifically advises against pumping them up which a lot of guys feel is necessary to do. They go on to say soaking them is okay, but not necessary. I can post the exact quote if you need me to; it's in their catalogs.

No gasket and no bearing for your 89.

Comp also advises to remove the factory applied coating before installing the lifters. The coating is applied to increase shelf life and it's IMPORTANT (Comp's emphasis) it be removed before installing the lifters.

I suggest you re-read Comp's instructions to get a better understanding of what Comp says you should and shouldn't do.

Jake

Apeiron

I think I should have said add the preload.

JakeJr

Catalog #106-07 page 241, lower part of the page:

"All COMP Cam's roller lifters are shipped with grease coating on the outside shell to prevent rust and a thick grease in the roller bearing to keep the needles in place during assembly. Prior to installing the lifters in an engine it is important to wash all of the grease from the lifter and bearing with a suitable solvent or mineral spirits. After blowing the parts dry, totally immerse the lifter in fresh 30w engine oil for 30 minutes."

Page 237, same catalog, states it's "undesirable" to pre-pump hydraulic lifters full of oil . . . However pre-soaking in a bath of engine oil ". . . is a good idea, . . ."


On page 261 of catalog #106-00 the word IMPORTANT is in bold type. My bad on using the word "MUST"; the word I should have typed in my previous post is "IMPORTANT."

How to check piston to valve clearance, using the clay method, which is the method I prefer, is on page 21, catalog #106-00

I'm just trying to help.

Jake

JakeJr

Right. It slipped by me too.

That was a GOOD catch on your part because many guys over-look that all together.

Jake