pr3 vs pr4 vs p72 rods? what ones are the strongest?
#1
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pr3 vs pr4 vs p72 rods? what ones are the strongest?
i was in my basement this morning looking at these 3 rods i just happen to have laying around. i have never looked at them closly before. it was quite obvious that the pr3 (or jdm p30's) looked the strongest and they are the shortest by about 10mm. is this true. any other opinions? i would have thought the p72's were the stongest. hmmm
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the simple answer to your ? is that b16a (p30, pr3) rods are the strongest. THis is becuase of their shorter length, smaller lever arm...you get the idea=less stress on the rod.
#3
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Re: (Bseriescivic5)
hmm cool, thats what i thought. they are also thicker. a b16 would prob be best for turbo then with like gsr pistons with a smaller dome making a smaller compression ratio
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Well not necisarilly. First the stock GSR piston isnt going to last long at high boost. The ringlands love to fail at much more than 250. but yes the b16a rod in general should be pretty strong
#5
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Re: (Bseriescivic5)
so you could do like a b16 bottom end with forged pistons and maybe homesafe for 300? ya i know what you mean. i have blown out my ring lands before. not much fun!
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Re: (the.hamburglar)
I was thinking about this also. I happen to have a brochure for the 94 delsol from honda. It states in there that the rods are forged steel. let me scan it tomorrow and show you guys. I'm assuming honda meant for the b16 model
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#8
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I dunno about all that. That could be a simple marketting scheme. But yes you would prolly be ok for 300 with stock b16a rods. But remember its all in the tune. And if your gonna be taking the motor apart anyway, y not do the rods too? Its just gonna hold you back later down the road. Not to mention what happens if you spin a rod bearing, and the rod snaps in half cuz its cast.? destroyed your whole block.
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not at all dude. First off, you will have to get the block bored and honed, all that good ****. Then you gotta get the whole rotating assembly balenced by a good machine shop, this includes crank rods pistons. Doesnt matter if they are stock or not, still has to be ballenced. Its really not that much more expensive. Pick up a set of eagle rods for 300 and you will be able to make 600+
#11
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Re: (Bseriescivic5)
thats going to be like another G at the machine shop and its still not going to be as reliable as the stock rods and pistons and bearings.
#13
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Re: (Bseriescivic5)
i have read some articles from the engineers at honda that state the gsr rod is stronger due to different metalurgy, which is also why they were able to use a narrower rod in the gsr, if you have a good scale can you weigh the gsr rod and the b16 rod, im curious to see the difference
#14
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Re: (Bseriescivic5)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Bseriescivic5 »</TD></TR><TR><TD CLASS="quote">Reliable? r u kidding? It would be a fully built motor with superior parts to stock so how would it not be as "reliable?"
</TD></TR></TABLE>
meaning bearing selection. im just worried about spinning bearings with all that extra hassle of aftermarket stuff.
</TD></TR></TABLE>
meaning bearing selection. im just worried about spinning bearings with all that extra hassle of aftermarket stuff.
#15
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Re: (the.hamburglar)
aftermarket rods dont cost anymore to use than stock rods, aftermarket pistons are balanced out of the box as well as the rods, all you gota do is bore/hone, measure rod/main clearances and slap it together
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actually i wouldnt trust that they are ballenced. Its always a good idea to have them double checked. Furthermore, you will need new bearings anyway, ACL race coated are like 150 bucks and they are superior to OEM. (although OEM are still good) so unless you are haveing and oil leak issue or spining the motor to 10k you should be fine.
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Re: (Bseriescivic5)
there was a thread not too long ago by Earl (R.I.P.) stating that u shouldnt use the ACL race bearings in anything but a motor u r willing to tear down frequently for inspection.
So just use the regular ACLs for everything but a race engine.
So just use the regular ACLs for everything but a race engine.
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ACL coated are harder bearings, less friction, i wouldnt think you would need to tear down that much more frequently than normal Bearings. Not to mention they can take ALOT more abuse.
#19
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Re: (Bseriescivic5)
it all depends on the clearances, if the bearing has proper clearances it dosnt really matter what it is. race bearings are thinner than normal so they have more clearance.
#21
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Re: (JDogg)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JDogg »</TD></TR><TR><TD CLASS="quote">it all depends on the clearances, if the bearing has proper clearances it dosnt really matter what it is. race bearings are thinner than normal so they have more clearance.
</TD></TR></TABLE>
ya but if they are thinner you will loose oil pressure right. what i really dont understand is how you select the bearings you need because every honda engine has different journal sizes. and with aftermarket rods im sure eagle for example would have all the same size journals but not every honda crank is the same. you need to follow that color code chart right?. so if all acl bearings are the same then you are not getting the right tolerances. some might be tight and some might be loose making your motor only last 10,000k making it unreliable. i wouldnt want to go on a 500 mile road trip with that.
so how can you use honda bearings with eagle rods? when i took apart my motor the bearings were color coated and i would have had to order each bearing one by one from honda according to the color. in fact some of the bearings i couldnt even see some of the colors and said screw it im keeping the bearings because they were still within tolerance using plastigauge. since i kept the bearings i kept the stock rods and pistons and just ended up doing and hone and new rings and how im boosting on that, 5psi.
</TD></TR></TABLE>
ya but if they are thinner you will loose oil pressure right. what i really dont understand is how you select the bearings you need because every honda engine has different journal sizes. and with aftermarket rods im sure eagle for example would have all the same size journals but not every honda crank is the same. you need to follow that color code chart right?. so if all acl bearings are the same then you are not getting the right tolerances. some might be tight and some might be loose making your motor only last 10,000k making it unreliable. i wouldnt want to go on a 500 mile road trip with that.
so how can you use honda bearings with eagle rods? when i took apart my motor the bearings were color coated and i would have had to order each bearing one by one from honda according to the color. in fact some of the bearings i couldnt even see some of the colors and said screw it im keeping the bearings because they were still within tolerance using plastigauge. since i kept the bearings i kept the stock rods and pistons and just ended up doing and hone and new rings and how im boosting on that, 5psi.
#22
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well the idea of the game is to start with a brand new OEM crank with as true of jornals as possible,that way you can run a 1-size fits all bearinng like ACL coated. they also offer different sizes for each bearing, thats the whole idea of blueprinting and checking all tolerances, and clearences. Machineing is KEY
#23
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Re: (Bseriescivic5)
i dont ever machine a honda crank.. if its not good then its garbage imho
but every manufacturer of bearings has a different size, clevites are not the same as acl, then there is uncoated, coated, etc.. only in rare cases do i have something so far out that i have to use honda bearings (they have a HUGE range in sizes). but this is where a ton of bearings being instock and high quality measureing tools and the ability to use them well nad repeatable is key. get some bearings, measure em, if htey dont work get some different ones.
but every manufacturer of bearings has a different size, clevites are not the same as acl, then there is uncoated, coated, etc.. only in rare cases do i have something so far out that i have to use honda bearings (they have a HUGE range in sizes). but this is where a ton of bearings being instock and high quality measureing tools and the ability to use them well nad repeatable is key. get some bearings, measure em, if htey dont work get some different ones.
#24
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Re: (Bseriescivic5)
The race bearings are less eccentric than the street bearings.When a rod gets elongated the parting line area gets pulled in.This is what generally causes spun bearings.It wipes out the oil film and its good bye bearing.Street bearings are oval shaped (wider at the parting line) so when a weaker stock rod gets defomed there is still clearance all the way around.Race bearings are designed for a performance rod that dosen't get as deformed.They are a lot less oval.When you put a race bearing in a stock rod and the rod deforms you lose the oil film.