What bearings to get my 408?

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mopar4x4stroker

mopar4x4stroker

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I'm cumming down home stretch with my build here and need some bearings for cam,rods,mains. This (as many already know) will be for my 86 full size that will be a city driver/weekend hauler/wheeler. Pretty low rpm application. Scat cast crank and I beam rods.

What are my options?

What do you guys suggest?
 
I like std groove mains, you'll need the narrow rod bearings because of the cast crank. I prefer Durabond cam bearings but any will do for you.
 
I'll just list ALL the bearings that I find on summit under Dodge/360/LA.

Obviously not too much confusion with rod bearings being summit only lists sealed power. I'm having a hard time deciding between brand/material/price for cam/mains. The only area I can really save a buck is cam bearings. Is it worth it to run cheaper bearing for the cam(dura bond), or should I just run all sealed power to be safe? Isn't sealed power made by Federal? I'm a rockie, the only brands I was familiar with was Federal modul and Clevite. I'm not familiar with Dura bond, sealed power, speed pro, king, ect. Why does summit not list Federal?


Heres all the materials? Anyone care to elaborate on these?

Bi metal, chill cast
Bi metal, lead-based
Bi metal, fluoropolymer lead-based
Bi metal, alecular alloy
Bi metal aluminum alloy

Tri metal copper-lead alloy
Tri metal, TM-77

B-1
B100

Tin based

Alecular silicon

Steel backed


Heres what summit lists for bearings....

Cam:

Dura-Bond:
PD-16: Direct replacement: Bi metal, lead-based micro babbit ($15.95)
PD-25: Direct replacement: Bi metal, lead-based micro babbit ($19.95)
PDP-16: Performance: Bi metal, chill cast micro babbit ($32.95)
PDP-25: Performance: Bi metal, chill cast micro babbit ($45.99)
PDP-16T: Performance: Bi metal, fluoropolymer lead-based micro babbit ($63.95)

Clevite:
SH1112S: Direct replacement: B-1 ($31.95)
SH875S: Direct replacement: Steel backed micro babbit, B-1 ($37.95)

King:
CS527BB: Direct replacement: Bi metal, lead-based micro babbit: ($35.95)
CS512BB: Direct replacement: Bi metal, lead-based micro babbit: ($38.95)
CS512HP: Performance: Bi metal, chill cast micro babbit: ($82.95)

Sealed Power:
Z1484M: Direct replacement: Tin based babbit, B100: ($29.95)
Z1451M: Direct replacement: Tin based babbit, B100: ($36.95)


Rod:

Sealed Power: chamfered stock size
Z87125CH: Performance: Tri metal copper-lead alloy: ($75.99)

Main:

Clevite: 1/2 stock size
MS1051P: Direct Replacement: Tri metal, TM-77: ($81.95)

King: 1/2 stock size
MB517SI: Direct Replacement: Alecular silicon: ($62.95)
MB510AM: Performance: Bi metal, alecular alloy: ($79.95)

Sealed Power: 1/2 stock size
Z4999MA: Performance: Bi metal aluminum alloy, A-Series: ($59.95)

Sealed power: 3/4 stock size
Z4948MA: Performance: Bi metal aluminum alloy, A-Series: ($69.95)
Z4948MA: Performance: Bi metal aluminum alloy, A-Series: ($71.95)

Speed Pro: 3/4 stock size
Z120M: Performance: Tri metal copper-lead alloy: ($71.99)
 
I use full groove bearings as Im running boost and N20 on my 360. This way the rod bearings have full time oiling.
 
1wild&crazyguy said:
Clevite rod=CB481HN
Click to expand...
Dont the rods have to be chamfered?

I use full groove bearings as Im running boost and N20 on my 360. This way the rod bearings have full time oiling.
Click to expand...
Yea I understand the theory, but then you gotta think. You sacrifice surface area for the "loaded shell" just for added oiling to the jornal. Wich adds volume and weight to the cyl wall/rings/pistons that would result blowbye(deto) and windage at high rpm. In my case full groove could be a good thing for ideling on the street but not worth it for loss in oil pressure and surface are. Then again I can see in a boost/gas application the added oil would help cool the piston. I guess you can never have your cake and eat it too.

Then you got 3/4 groove, wich might be a perfect in between, or just a gimick for added cost. I think I'll go with 1/2 groove since they've proven themselves for years in hot/mild street applications w/ clean oil, good pressure, and tolerances. Unless someone gives good reason otherwise.

I'm just unsure to which brand and material is best.
 
On my 408 I'm running Clevite CB481HXN on Rods (.003 undersized), and Sealed Power Competition Series main bearings SLP-120M 3/4 groove (.003 undersize). Using Eagle cast steel crank (PN# 103604000).

Stock style oil pump with 55 PSI @ 2000RPM and 25 PSI at idle (1000RPM) engine temp at 185-190 degrees.

Info from from Summit Racing web site:

"Clevite H-Series rod bearings were primarily developed for NASCAR racing, but are well suited to other types of competition engines. They're especially good for engines that run at medium-to-high revs. They have hardened-steel backings with thin overlays and a high crush factor, plus a medium level of eccentricity. H-Series bearings have enlarged chamfers at the sides for greater crank-fillet clearance and are made without flash plating for better seating. They are available with various under-sizes, including 0.001 in. of clearance for polished journals."


"If you're building a serious competition engine, then you'll definitely want to check out Sealed Power Competition Series main bearings. They were developed in NASCAR and Pro Stock competition, so you know they're tough. They're built on premium 1020AK steel backings and overlaid with Sealed Power's super-duty H-14 alloy. That's covered with a nickel barrier, followed by a thin lead-tin-copper overplate. However, unlike other performance bearings, there is no flash tin layer on top of that. Sealed Power's engineers have determined that such a layer can actually move around under high loads--sometimes with undesirable consequences. These bearings have 3/4 oil grooves for enhanced lubrication, while maintaining a maximum bearing surface area. They also feature Sealed Power's exclusive contoured-flange thrust bearing technology for higher thrust-loading capacity."
 
In terms of materials, I think you might be overthinking things. King is the best in terms of bearings IMO. You don't need them, nor do you need the 3/4 or full groove, or anything fancy. In terms of cam bearings, the Durabond tend to not need so much clearancing after the cam is installed, at least that's what I've found. You've got a mild setup, a mild cam, and mild usage. There's not much reason to go fancy or expensive for it. You do need the narrow bearings 1Wild listed because of the fillet on the cast crank. Otherwise whatever is available and inexpensive should be fine.
 
I had to narrow stock app main bearings for the journal radius.

The second time around I just bought the full groove mains, they are narrower than stock ootb.

When it comes to full groove bearing psi loss.....well full time oiling will do that, as for clearances..thats 2nd to blame, mine are only .0024'ish on the mains and .0017'ish+ on the rods.

They have found less than 10 psi per 1000 rpm to be sufficient, as low 6-7psi per grand even.....however the add psi '@ idle for instance' & 'to an extent' will cool the bearing/journal faster and bring the viscosity back that all oils lose no matter the brand/cost....which is why I always run a 20w50 btw.

there is a line between enough psi to cool/lube and too much viscosity which is creating more heat when having to compress it.

I really hope I dont see lower than 25psi at idle, but it may take a spring in the oil pump to insure that.

just rambling now...
 
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