Highest Zinc Level Oil for Rebuilt 350 CI Engine

Status
Not open for further replies.
Joined
May 30, 2009
Messages
4
Location
NC
Just broke in freshly rebuilt 350 for my 55 Chevy. Drained off Brad Penn break in oil and refilled with Pennzoil Dino 10W-30 for 500 mile break-in. Looking for best oil once 500 miles are up. Flat tappet cam, so want to feed it a zinc-enriched oil and noticed Mobil 1 10W-30 High Mileage has high levels of Zinc...any thoughts on protection level of running it vice a good Dino oil with an additive like ZDDPlus?
 
unless you are running high life comp cams and/or in combination with stiff valve springs, the need of extra ZDDP on a rebuilt, stock cam configuration is questionable.

Granted, you purchased a properly casted and coated replacement cam from reputable company and rigidly abide by the break-in procedures, then after successful broken in, the cam can live a happy, long life in low ZDDP.

Afterall: all properly manufactured cams came pre-coated with phosphate coating on the cam lobes for the initial break in process.

Q.
 
Running Edelbrock Performer package, 58cc heads, .40 over...making approx 350 hp. Believe it's built to last, just navigating through the various oils for the right one. Thanks.
 
First off, I agree with everything Quest said. Once you've got it broken in, you can use "normal" ZDDP level oils.

Second, you asked about M1 HM vs. a conventional oil with a ZDDP additive. On that one, I'm always a proponent of using a fully-formulated single product rather than frankenbrewing up something out of two products that were never rigorously tested together. I'd go for the M1, or if not that then another synthetic oil with a ZDDP level that makes you comfortable. There are products out there from Amsoil, Redline, Royal Purple, and others that meet that description. RP's HPS line of oils is intended for this sort of application, for example.
 
I don't see any reason to use a fancy oil here, unless you want to. Rotella T5 10w-30 would fit the bill, and has moderately higher ZDDP levels; enough that you don't need any additives.

Rotella VOA
 
I think putting in the Pennzoil dino for a 500-mile break-in is a mistake. The engine is in the part of its life where it needs a high zddp oil plus time at operating temperature to build up the protective wear coating that zddp forms.

Why not just use Brad Penn 10w30? It's got high zddp.
 
Originally Posted By: Bandito440
I don't see any reason to use a fancy oil here, unless you want to. Rotella T5 10w-30 would fit the bill, and has moderately higher ZDDP levels; enough that you don't need any additives.

Rotella VOA

+1 Or just run QS Defy. 350hp from a 350 .040 over is pretty mild. Overkill would be M1 15W-50.
 
After break in, I'd stay away from additives and go with a Brad Penn product or maybe Kendall GT-1 High Performance (the 20w-50 is about 1,200 zinc and it cleans unlike most racing oils.) The problem with nearly all 10w-30 and 10w-40 dino oils is that they're less than 900. You may also consider Rotella T 15w-40.
 
Originally Posted By: mdlab
Just broke in freshly rebuilt 350 for my 55 Chevy. Drained off Brad Penn break in oil and refilled with Pennzoil Dino 10W-30 for 500 mile break-in. Looking for best oil once 500 miles are up. Flat tappet cam, so want to feed it a zinc-enriched oil and noticed Mobil 1 10W-30 High Mileage has high levels of Zinc...any thoughts on protection level of running it vice a good Dino oil with an additive like ZDDPlus?


Just an HDEO would be more than adequate. My buddy's dad's S10 that we did the engine for had a Lunatti Voodoo in it and all we ran for oil was Esso XD-3 15w-40 and when we eventually got around to converting it to roller, the cam looked perfect, as did the lifters.
 
Does Brad Penn make a 15W-40 or a 15W-50 ? That would probably work good.

Here's a thought: Call up Brad Penn and Joe Gibbs and ask them what they'd recommend.
 
Originally Posted By: mdlab
Drained off Brad Penn break in oil and refilled with Pennzoil Dino 10W-30 for 500 mile break-in.


You drained the expensive Brad Penn break in oil to break in with cheap dino oil? Not a good move.

You need to put what you had back in.

I don't understand why people think they need to dump the initial fill on a rebuild within minutes of operation. Just change the filter in case it's plugged with break in grease.
 
Appreciate the dialogue. Drained off the Brad Penn IAW my machine shop's direction...it was the zinc enriched 30W designed only for the break in run of 30 minutes, not beyond that. The Dino oil was also at the direction of the machine shop (same direction given by GM for Chevy/GM crate motors) to be used for first 500 miles, then a 10w-30 synthetic is recommended. Trying to determine if using high mileage M1 synthetic for its high zinc content might have other unintended consequences. It's among the highest zinc content (higher than Brad Penn, et al) I've found and is readily available and reasonably priced.
 
Originally Posted By: mdlab
Appreciate the dialogue. Drained off the Brad Penn IAW my machine shop's direction...it was the zinc enriched 30W designed only for the break in run of 30 minutes, not beyond that. The Dino oil was also at the direction of the machine shop (same direction given by GM for Chevy/GM crate motors) to be used for first 500 miles, then a 10w-30 synthetic is recommended. Trying to determine if using high mileage M1 synthetic for its high zinc content might have other unintended consequences. It's among the highest zinc content (higher than Brad Penn, et al) I've found and is readily available and reasonably priced.

If you don't foul-up the Mobil 1 with other additives, it'll be just fine. If the builder nor Chevy/GM didn't recommend a higher zinc oil, don't worry about it. Enjoy your new engine!
Kevin
PS - I obsessesd about zinc for years especially after my small block Ford was rebuilt with an upgraded cam and stiffer springs. After a LOT of study here, I've concluded that trying to second guess petroleum engineeers and tribiologists with additional additives was not an effective strategy.
 
Add a bottle GM oil additive #88862586 designed for cam/lifter break in and regular use in flat tappet engines.
 
Last edited:
Originally Posted By: turtlevette


I don't understand why people think they need to dump the initial fill on a rebuild within minutes of operation. Just change the filter in case it's plugged with break in grease.




Because with flat lifters it's the right thing to do. Especially if the cam vendor supplies an etching break in lube for the cam lobes, with instructions to keep it off the bearings. That stuff needs to be drained immediately after cam break in (20-30 minutes at 1500 rpm or higher)
 
Status
Not open for further replies.
Back
Top