|
Re: aluminum main caps
[Re: Deepockets]
#1351649
12/15/12 03:08 PM
12/15/12 03:08 PM
|
Joined: Oct 2005
Posts: 8,882
Ontario, Canada
Stanton
Don't question me!
|
Don't question me!
Joined: Oct 2005
Posts: 8,882
Ontario, Canada
|
Quote:
when i talked to me local machine shop about useing the aluminum mains, he did'nt suguest them.
Either he's a Chevy guy or he doesn't think your power level warrants them.
|
|
|
Re: aluminum main caps
[Re: Stanton]
#1351650
12/15/12 03:21 PM
12/15/12 03:21 PM
|
Joined: Jan 2003
Posts: 15,439
Val-haul-ass... eventually
BradH
Taking time off to work on my car
|
Taking time off to work on my car
Joined: Jan 2003
Posts: 15,439
Val-haul-ass... eventually
|
Quote:
Quote:
when i talked to me local machine shop about useing the aluminum mains, he did'nt suguest them.
Either he's a Chevy guy or he doesn't think your power level warrants them.
Or he's a Mopar guy who doesn't believe in using aluminum main caps, regardless of the power level. I know of a couple of Mopar engine builders with that opinion.
|
|
|
Re: aluminum main caps
[Re: Performance Only]
#1351651
12/15/12 03:22 PM
12/15/12 03:22 PM
|
Joined: Jan 2003
Posts: 1,938
Sonora CA
Mopar_Rich
top fuel
|
top fuel
Joined: Jan 2003
Posts: 1,938
Sonora CA
|
Quote:
Rich, That's the first time i've heard anyone say anything about fluctuating oil pressure when using aluminum caps. I've installed close to a hundred sets over the years and have never had such an issue.
I always align bore the block when installing any cap conversion whether it's steel or aluminum. IMO that's the proper way to do it. some shops will bore the mains to within .001 and hone the rest, which is okay as well.
I believe the aluminum caps help dampen harmonics to some degree. In any case, I think it's been a time tested upgrade to help our stock block combo's live a bit longer when pushed beyond their normal limits. 
Well, I guess because you are doing things right by setting the bearing clearances accordingly. The oil pressure change is from the extra expansion of aluminum in a hot engine. It doesn't really hurt anything because it's only noticeable at idle on a hot engine. As we all know if the pressure comes right up with RPM we're good to go. There's no question they help absorb shock as do aluminum rods.
|
|
|
Re: aluminum main caps
[Re: BradH]
#1351652
12/15/12 04:56 PM
12/15/12 04:56 PM
|
Joined: Nov 2004
Posts: 3,544
Syracuse,NY
CompWedgeEngines
master
|
master
Joined: Nov 2004
Posts: 3,544
Syracuse,NY
|
I happen to be one of the builders that likes them, uses them, and has what I would consider great success with them. As Rich says, there are some things to be aware of, and machining them can be scary to the guys that dont understand them, but when done properly, I believe they serve a great purpose.A good friend of mine thought I was nuts the first time we spoke of them,and he couldnt for the life of him understand WHY? Yes, he builds a lot of Chevys ( you simplycant compare a Dart Big M block to a stock block Mopar)...lol....but once he saw them in cars running 1200 passes, he became a believer. Its all in the proper machining, set up, timing, and bearing clearances.....carry on....
RIP Monte Smith
Your work is a reflection of yourself, autograph it with quality.
WD for Diamond Pistons,Sidewinder cylinder heads, Wiseco, K1 rods and cranks,BAM lifters, Morel lifters, Molnar Technologies, Harland Sharp, Pro Gear, Cometic, King Engine Bearings and many others.
|
|
|
Re: aluminum main caps
[Re: CompWedgeEngines]
#1351653
12/16/12 01:19 AM
12/16/12 01:19 AM
|
Joined: Jan 2003
Posts: 177
JCFcuda
member
|
member
Joined: Jan 2003
Posts: 177
|
I have them on my 500 Rb . Ive never seen any oil pressure issues. wouldn't Alu expand in all directions so how would it increase bearing clearance? Oil pressure was great until I peeled a crane rocker off my head not so good then and then ran it all the way back to the trailer duh  . Jim
|
|
|
Re: aluminum main caps
[Re: Cab_Burge]
#1351658
12/16/12 02:48 PM
12/16/12 02:48 PM
|
Joined: Nov 2003
Posts: 5,160
Texas
dannysbee
master
|
master
Joined: Nov 2003
Posts: 5,160
Texas
|
I think there is a place for both doctile iron and aluminum. The mixture of unlike metals does not concern me too much as that will always be the case with a aluminum block. Milodon has doctile iron caps available.
Getting old just means you were smarter than some and luckier than others.
|
|
|
Re: aluminum main caps
[Re: dvw]
#1351661
12/18/12 07:36 PM
12/18/12 07:36 PM
|
Joined: Dec 2008
Posts: 290
Norwalk Ohio
cudasteve68
enthusiast
|
enthusiast
Joined: Dec 2008
Posts: 290
Norwalk Ohio
|
Quote:
For what it's Worth the only set I ever ran did have slightly less oil pressure at Idle when hot. This was using the same main clearance .003" as I use with steel caps.
Doug
I have noticed the same issue in the late rounds, however you will notice a drop no matter what caps you use. I have found two answers to this problem, and they both work GREAT!!!!
1) Ride the Harley on race day & leave the Racecar in garage.
2) Become a first round runner up like me.
Both keep oil temps down & pressure up!!!
|
|
|
|
|
I have used the Mopar Ductile iron with really good results 
Now, how to decide between steel and aluminum caps 
.JPG){kind=link}