|
Re: Main bearings
[Re: moparts]
#888542
01/01/11 03:48 AM
01/01/11 03:48 AM
|
Joined: Jun 2010
Posts: 85 europe
WBR
OP
member
|
OP
member
Joined: Jun 2010
Posts: 85
europe
|
This was hot engine vs hot. Got me some plastigage and got to measure a few journals. The middle one showed 002 and the front one less than that. So i think clearances have been tight. I think it should be more like 0025 with new bearings. Will see what i find at the rod journals. I asked at the speed shop for 001 under bearings, but he didn`t have any listed on the 0.02 under size. Are there any available or is a trip to the crank grinder my only option to gain more clearance? I also bought ARP main bolts, but they don`t have the provision for a windage tray. What`s my options on that one? And thanks for the help. I really appreciate it!
Street driven, 421 Sb, NA, 9.98/137
|
|
|
Re: Main bearings
[Re: WBR]
#888543
01/01/11 10:14 AM
01/01/11 10:14 AM
|
Joined: Jun 2010
Posts: 85 europe
WBR
OP
member
|
OP
member
Joined: Jun 2010
Posts: 85
europe
|
Got the rod journals measured. 0.oo15. bearings looked pretty good. Is this too tight?
Street driven, 421 Sb, NA, 9.98/137
|
|
|
Re: Main bearings
[Re: WBR]
#888544
01/01/11 10:57 AM
01/01/11 10:57 AM
|
Joined: Nov 2003
Posts: 36,041 Lincoln Nebraska
RapidRobert
Circle Track
|
Circle Track
Joined: Nov 2003
Posts: 36,041
Lincoln Nebraska
|
yes too tight. the most critical area (in the oiling system) is providing for the rod journals/bearings. Check w your crank grinder but might not be able to get the clearance you need by polishing. It'll make it out of round. Polishing is more for achieving a smooth finish. Keep searching for the correct oversize bearings you need. Peruse the SB "parts for sale" for a set of the shouldered 4 main bolts you need for the tray and do not use the large washers on the large bolts "if included" w them. there's a set (+ the tray) in there a day or 2 ago for $25 & I'm tempted to grab it myself even tho I dont need it (at the moment) cause the price is right and someday I will! Use flat washers or flat spacers between the tray and the large bolt shoulder to adj the tray height. Also check that the main bolts are not bottoming out
live every 24 hour block of time like it's your last day on earth
|
|
|
Re: Main bearings
[Re: RapidRobert]
#888545
01/01/11 03:12 PM
01/01/11 03:12 PM
|
Joined: Jun 2010
Posts: 85 europe
WBR
OP
member
|
OP
member
Joined: Jun 2010
Posts: 85
europe
|
I `ll give a call to our local parts supplier. They will know if such bearings are available. otherwise, it`s a trip to crankgrinder once again... Thanks everyone for the help!
Street driven, 421 Sb, NA, 9.98/137
|
|
|
Re: Main bearings
[Re: WBR]
#888546
01/01/11 03:48 PM
01/01/11 03:48 PM
|
Joined: Nov 2003
Posts: 36,041 Lincoln Nebraska
RapidRobert
Circle Track
|
Circle Track
Joined: Nov 2003
Posts: 36,041
Lincoln Nebraska
|
Let us know how it turns out
live every 24 hour block of time like it's your last day on earth
|
|
|
Re: Main bearings
[Re: RapidRobert]
#888547
01/04/11 06:25 AM
01/04/11 06:25 AM
|
Joined: Jun 2010
Posts: 85 europe
WBR
OP
member
|
OP
member
Joined: Jun 2010
Posts: 85
europe
|
There is not such bearings available in that undersize. (.02+001). But the speedshop guy is also a known enginebuilder and he felt that i should be fine with clearances i have. But if i wanted more clearance i could take some from the backside of the bearings with a 400 grit paper. How does that sound to ya? Could i be ok with what i have?
Street driven, 421 Sb, NA, 9.98/137
|
|
|
Re: Main bearings
[Re: WBR]
#888549
01/04/11 10:45 AM
01/04/11 10:45 AM
|
Joined: Jun 2010
Posts: 591 Champion City
The Sphinx
mopar
|
mopar
Joined: Jun 2010
Posts: 591
Champion City
|
Quote:
Got the rod journals measured. 0.oo15. bearings looked pretty good. Is this too tight?
.0015 to .003 is the spec. You are not too tight.
|
|
|
Re: Main bearings
[Re: The Sphinx]
#888550
01/04/11 03:15 PM
01/04/11 03:15 PM
|
Joined: Jun 2010
Posts: 85 europe
WBR
OP
member
|
OP
member
Joined: Jun 2010
Posts: 85
europe
|
Ok. So i should be good to go as it is. i`ve heard that from several now. that would be good money wise. Would be so many places to spend that money...
Street driven, 421 Sb, NA, 9.98/137
|
|
|
Re: Main bearings
[Re: WBR]
#888551
01/04/11 06:47 PM
01/04/11 06:47 PM
|
Joined: Nov 2003
Posts: 36,041 Lincoln Nebraska
RapidRobert
Circle Track
|
Circle Track
Joined: Nov 2003
Posts: 36,041
Lincoln Nebraska
|
for a daily driver .0015 would not be too tight but for a 1/4 miler I would definitely want more but I dont want to cause you undue worry & good luck & stay in touch w us.
live every 24 hour block of time like it's your last day on earth
|
|
|
Re: Main bearings
[Re: RapidRobert]
#888552
01/04/11 11:31 PM
01/04/11 11:31 PM
|
Joined: Jan 2003
Posts: 4,664 Newfoundland
mopar_man
master
|
master
Joined: Jan 2003
Posts: 4,664
Newfoundland
|
maybe I'm getting too old or loosing it but I always thought if you want more clearance on a bearing you would go 1-2 thou. over size. If you cut a crank 10 thou. under standard size then you would install a 10 thou. under bearing .......forgetting clearence for the moment. If your crank is standard and you need more clearence wouldn't you have to install an over(standard size) bearing to give you the desired clearence. Maybe our termology is different here in Canada.
|
|
|
Re: Main bearings
[Re: RapidRobert]
#888554
01/05/11 03:04 AM
01/05/11 03:04 AM
|
Joined: Feb 2007
Posts: 1,025 Las Vegas, NV
dodgeboy11
super stock
|
super stock
Joined: Feb 2007
Posts: 1,025
Las Vegas, NV
|
A good rule of thumb is .001" of bearing clearance for each inch of crank journal. So .0025"-.0030" on the mains and .0020"-.0022" on the rods. If the engine is going to be run warm quite often, you can go tighter, or just run a HV pump and do a little oil system massaging (smoothing, enlarging passages). I don't really recommend doing it (though I have in a pinch), but I've used worn out scotch brite (green) on the face of the bearings to gain clearance. Keep clean solvent running on it while you run the SB across the bearing. I hold the bearing half in one hand and scotch brite on my thumb of the other. I cover half the bearing and count the number of strokes. Flip the bearing, do the other half. Then I flip it again and lightly go across the whole bearing face. You won't gain much, but if you're close it will work. And if you go to copper, you've gone too far. Kind of a last ditch effort sort of thing. The best thing to do is take the block to the machine shop and have the main housing bores opened up and the big ends of the rods opened up as well. As for filters, the PH series fram filters have no place on anything performance. The TG filters are closer to a WIX type filter and I'm not afraid of them as much. Is the plug under the #5 main cap that directs oil to the filter still there? That'll cause low oil pressure.
|
|
|
|
|
|