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11-10-2005, 08:11 PM
joe bogger

thank you techinspestor1 for explaining that a little, see that is something I did not know and maybe that is why the bearings failed. I got the block and rotating assembaly all assembled on a deal and was told it had a fresh rebuild and was ready for the top end then run it but when I tore the engine down to see for shure the crank and rod bearings had goudges in them so I put a new crank and bearings in it to be safe but did not know the rods need cross hatches in them also. Do the cross hatches in the rods serve the same purpose as the ones in the cylinders.
11-10-2005, 08:13 PM
erik erikson

Quote:

Originally posted by joe bogger
thank you techinspestor1 for explaining that a little, see that is something I did not know and maybe that is why the bearings failed. I got the block and rotating assembaly all assembled on a deal and was told it had a fresh rebuild and was ready for the top end then run it but when I tore the engine down to see for shure the crank and rod bearings had goudges in them so I put a new crank and bearings in it to be safe but did not know the rods need cross hatches in them also. Do the cross hatches in the rods serve the same purpose as the ones in the cylinders.

NO,THEY DON'T.THEY ARE JUST HONING,OR MACHING MARKS.
11-10-2005, 08:38 PM
joe bogger

Well isnt cross hatches in a cylinder from a hone.
11-10-2005, 09:00 PM
techinspector1

Quote:

Originally posted by joe bogger
Well isnt cross hatches in a cylinder from a hone.

Yes, but the cross hatch marks in the cylinder are to roughen up the bore slightly so the rings can wear-in. They are also there to hold a little oil on the walls. As Erik said, the marks on the big ends of the rods do not serve the same purpose, they are just there because that's how the big ends are sized, with a stone.
11-10-2005, 09:13 PM
pat mccarthy

Quote:

Originally posted by techinspector1
Yes, but the cross hatch marks in the cylinder are to roughen up the bore slightly so the rings can wear-in. They are also there to hold a little oil on the walls. As Erik said, the marks on the big ends of the rods do not serve the same purpose, they are just there because that's how the big ends are sized, with a stone.

rod can be honed this is done and will have cross hatch marks or they can be bored with a rod boring machine .the machine i have is made by sunnen and i would say that 90% of the rods out there are done this way but not all.
11-10-2005, 09:28 PM
techinspector1

Thanks Pat, it has been several years since I built a motor and had rods re-sized, so chances are there is more new machinery and methods in use that I don't know about. I've used the same old guy for about the last hunnerd years :LOL:
11-10-2005, 09:28 PM
joe bogger

so the cross hatch on the rods surve no reel purpose. There just machining marks. Iam guessing you look at the cross hatches in the rods to if the bearing starts to get a liitle loose then it would start to where them out. Right.
11-10-2005, 09:41 PM
techinspector1

Yeah, everything is gonna squirm a little under the pressures that a motor is subjected to, so like Erik said, if the marks are worn away or gone because the shells are grating against the rod and cap, you know the shells have made the "pinch" looser in the rod/cap and it's time to do some R & R.

I've seen an experienced machinist mic a rod bore with the rod laying on the bench and then pick it up and hold it in his hand for a minute, then mic it again and there will be a couple of ten-thousandths difference in the measurements due to expansion just from the heat in his hand. A rod/cap assembly is actually a pretty flimsy piece of equipment. It's amazing that it can take all the punishment it takes and keep on tickin' through millions of cycles.
11-10-2005, 09:54 PM
techinspector1

While we're on the subject of rods, I'll add this....

If you're going to use stock rods, at least buy the best rod bolts that money can buy and tighten them using the "stretch" method with a stretch gauge rather than depending on a pre-determined torque figure........
http://chevyhiperformance.com/techarticles/49258/
11-10-2005, 09:58 PM
pat mccarthy

Quote:

Originally posted by techinspector1
Thanks Pat, it has been several years since I built a motor and had rods re-sized, so chances are there is more new machinery and methods in use that I don't know about. I've used the same old guy for about the last hunnerd years :LOL:

my rod machine was made in 1957 floor model mbb1290 sunnen the rod boring machines have been around for a very long time the rod boring machines were used to cut babbit pored rods to sizes and are still used to day and still made i have see this type of machinery ran by old flat belt s. the rod boring this done on very big rods to like somthing like diesel s rod s and are use on the small end pin end for bushing the pin end
11-11-2005, 11:05 AM
joe bogger

I am not going to run stock rods in the next rebuild. I am looking at a rotateing assemly from speed omotive, ether the 383 or the 395. dont know yet. But an aftermarket rod will stretch and where also right it just takes longer.
11-11-2005, 05:36 PM
pat mccarthy

the scat I beam are good and if you are driving this every day i wound keep way from bushed pins and go to a press in pin so you do not beat them out. the press pin make the rod stronger. I beam rods are ligther than H beams. i would look at i beam rods and buy a set of srp pistons and keep a way from hypereutectic if you are buzzing this up you want the mass as ligth as you can watch out some of them cheap I beam rods out there are no better then what you had. look for rods made from 4340 steel and ohio crank and competition products is were i would buy from but thats my opinion:whacked:
11-11-2005, 05:40 PM
pat mccarthy

Quote:

Originally posted by techinspector1
Aw, come on Joe, we've got a 3-pager goin' here. With any luck, we could stretch it to 6. Keep postin'.

i think we can get 6 out of this hop on techinspector:LOL:
11-11-2005, 05:51 PM
76GMC1500

Currently, Summit's brand of I-beam rod is actually a Scat rod. It is a decent piece, but is a little heavier than stock at 630 grams. I am using a set of them in my engine. No mallory had to be added to the crank for balance, even with KB hypereutectic pistons which are considered by some to be heavy. I am using bushed rods in a daily driver because they only cost $10 more than the press fit and saved me a lot of money not having to have the machine shop press them. I don't know where the idea of not using bushed rods in low hp street motors came from. Full floating wrist pins are used in most diesels which go many times longer between overhaul than gas, because of their increased durability and reliability. Floating wrist pin arrangements also have more bearing surface area to support the load, so the pressure on the wrist pin is more evenly distributed. I also disagree with a pressed pin making the rod stronger. When a pressed pin is driven in, it expands the small end of the rod a little which creates a tensile force in the steel which adds to the tensile force on the rod during a piston direction change.
11-11-2005, 05:59 PM
erik erikson

Quote:

Originally posted by pat mccarthy
the scat I beam are good and if you are driving this every i wound keep way from bushed pins and go to a press in pin so you do not beat them out. the press pin make the rod stronger. I beam rods are ligther than H beams. i would look at i beam rods and buy a set of srp pistons and keep a way from hypereutectic if you are buzzing this up you want the mass as ligth as you can watch out some of them cheap I beam rods out there are no better then what you had. look for rods made from 4340 steel and ohio crank and competition products is were i would buy from but thats my opinion:whacked:

WHAT PAT SAY'S HOLD TRUE FOR ME 100 %.IN OUR SHORT TRACK ENGINE WE TURN TO 7,200 WE HAVE THE I- BEAM RODS WITH THE BETTER CAP SCREWS INSTALLED.WE HAVE RUN BOTH THE SRP PISTONS AND THE WIESCO PRO TRU PISTONS,THEY SEEM VERY SIMILAR.
11-11-2005, 06:26 PM
pat mccarthy

Quote:

Originally posted by 76GMC1500
Currently, Summit's brand of I-beam rod is actually a Scat rod. It is a decent piece, but is a little heavier than stock at 630 grams. I am using a set of them in my engine. No mallory had to be added to the crank for balance, even with KB hypereutectic pistons which are considered by some to be heavy. I am using bushed rods in a daily driver because they only cost $10 more than the press fit and saved me a lot of money not having to have the machine shop press them. I don't know where the idea of not using bushed rods in low hp street motors came from. Full floating wrist pins are used in most diesels which go many times longer between overhaul than gas, because of their increased durability and reliability. Floating wrist pin arrangements also have more bearing surface area to support the load, so the pressure on the wrist pin is more evenly distributed. I also disagree with a pressed pin making the rod stronger. When a pressed pin is driven in, it expands the small end of the rod a little which creates a tensile force in the steel which adds to the tensile force on the rod during a piston direction change.

why would you buy a rod from summit if made by scat ?? i can get them cheaper from scat?? press pin are stronger and did you get the pin fitted ? a diesel have bigger pin in them and the rod are made to be stronger. with the press makes aT out of the rod and will and dose make it stronger and a rod that is a floating the rod this weaker on the small end WHY less steel you bored it for a bushing and get back to me at 30.000 miles
11-11-2005, 07:14 PM
pat mccarthy

yes some shop press the pins in but the right way is with a rod oven and there may be a place for bushed rod but for evey day use i can not see it. a lot of bushed rods need to be fitted to the pin this is done with a sunnen rod hone or somthing like it and hone so it clearanced for the pin to work i have work on race engine where the the pin stop working on the bushing and now you are back to a press pin rod. you are only as good as the bushing how good are they ?? what is the make up will it last is it good bronze ? if it hammer out you need them rebushed and now you have to buy bushing and have them expande in the rods and hone to size this is takes some time to do and $$ i have done it and do not forget you need oil. a low rpm engine you have to make shure it get in them bushing
11-12-2005, 06:29 AM
joe bogger

Is a I beam rod stronger than an H beam. And if they are then why do they make a H beam rod. I was planing on SRP or Wiesco.
I also noticed you can get bearings with groovs on both halfs or one half, and with a whole in them or with out. What do theses do the help.
11-12-2005, 08:03 AM
pat mccarthy

I beam or H alot people have many veiws on this i have used many of both .steel what the rods is made of has alot to do with how good they are . i beam would take side loading better the hole in the rod bearing is to keep it from moving in alumm rod and i never see a full groovs on rods ? mains yes old hot rod trick more oil helps the rods but hurt the load handing of the bearings i use the 3/4 groovs on mains. rod bearings are cut down or chamfered for larger fillets on the crank
11-12-2005, 06:28 PM
erik erikson

Quote:

Originally posted by joe bogger
Is a I beam rod stronger than an H beam. And if they are then why do they make a H beam rod. I was planing on SRP or Wiesco.
I also noticed you can get bearings with groovs on both halfs or one half, and with a whole in them or with out. What do theses do the help.

VERY FEW PEOPLE NEED H- BEAM RODS IN A STREET CAR.I.M.O. THE H-BEAM ROD IS A NOT REALLY NEEDED IN A STREET CAR THAT WON'T SPEND MUCH OF IT'S LIFE AT HIGH R.P.M.S.
11-13-2005, 08:06 AM
joe bogger

Well I drove my truck to work,school or where ever I drove and every corner the engine seen at least 7,000 rpm. At what rpm should you go with the H beam. I am planing building power to 7500 on my next engine. It will be a 383 or a 395 I havent made the choice yet.
11-13-2005, 12:09 PM
joe bogger

Should I run a high cost race bearing or a all around good bearing like a clevlite 77. I would like this engine to last atleast a year. Even if I have to rebuild it five times. The longest time I have gotten out of a motor was about 5 months. People say I am Hard on them but I think I need to catch it and rebuild before it gernades.
11-13-2005, 01:39 PM
pat mccarthy

Quote:

Originally posted by joe bogger
Should I run a high cost race bearing or a all around good bearing like a clevlite 77. I would like this engine to last atleast a year. Even if I have to rebuild it five times. The longest time I have gotten out of a motor was about 5 months. People say I am Hard on them but I think I need to catch it and rebuild before it gernades.

yes thats is rigth. and on the rods and bearings H orI and race bearings. the `i have posted some on them and if you read it ?? the steel and the quality of the rod .you say hard on thing ? you can not buy rods for $190.and thing they will do the jod of a set of $350 or $1000. set you get what you pay for and race bearing are use on big radii cranks mich p 77 will work if you are not running a big radii
11-13-2005, 05:37 PM
joe bogger

Radii crank?? Do mean stroke or the radious of the jurnal. I am ether going to run a 3.75 or a 3.875 I am not shure yet. And I was running stock rods in those engines I was told a stock small block crank and rods would handle 500 hp. I cant say I can prove that because I have never dynod one of my engines but I am positve I not running even 400 hp. Now I dont know how many rpm's they can handle?
11-13-2005, 05:49 PM
pat mccarthy

the radii of the crank journals fillets on races cranks is.125 makes for a better crank . and on the small block crank? it is good till it brakes??this is hard to say have seem them brake. if you run this evey chance you get to 7000 i think you needs some good stuff
11-13-2005, 06:40 PM
joe bogger

I guess I dont know what you mean I have never heard of this. Is it the oil holes in the crank? Would you mind if you explained it.
11-13-2005, 06:58 PM
techinspector1

joe, the fillet radius is the corner of the rod journal surface where it comes up the cheek of the crank. The larger the radius, the stronger the crank. Pat has mentioned a radius of 0.125", that would obviously equal a diameter of 0.250", so if you were to lay a 1/4" twist drill into the corner of a crank that has been manufactured with a 0.125" radius, you should not be able to see any daylight between the drill and the fillet.

With a generous fillet, you may have to massage the bearing shells so that they don't ride against the fillet.
11-13-2005, 07:12 PM
pat mccarthy

Quote:

Originally posted by techinspector1
joe, the fillet radius is the corner of the rod journal surface where it comes up the cheek of the crank. The larger the radius, the stronger the crank. Pat has mentioned a radius of 0.125", that would obviously equal a diameter of 0.250", so if you were to lay a 1/4" twist drill into the corner of a crank that has been manufactured with a 0.125" radius, you should not be able to see any daylight between the drill and the fillet.

With a generous fillet, you may have to massage the bearing shells so that they don't ride against the fillet.

good job techinspector yes the bearings will need to be H type races bearings with is type of crank
11-14-2005, 10:09 AM
joe bogger

Thanks guys. Boy I dont think I have to many more questions. How about splayed main caps do they uses special bearing and you have to have the block line bored with the new caps instaled right. I may be running these but dont know much obout them and if I even need them.
11-14-2005, 01:44 PM
pat mccarthy

Quote:

Originally posted by joe bogger
Thanks guys. Boy I dont think I have to many more questions. How about splayed main caps do they uses special bearing and you have to have the block line bored with the new caps instaled right. I may be running these but dont know much obout them and if I even need them.

the block will need work for the caps do you need them?? you are going to have to decide how hi your going to buzz is engine to and how long and how many times . and how much money you have to spend ??all this talk on rods and bearrings and if you run it hard you will need very good valve train parts and good oil pan and damper.i hope i do not sound like a smart ass but you need to lean some stuff i dont know how much i can help you if you read my stuff and tech stuff is will help but you need to read some blooks i can not build the engine over the post for you will have to make some call s on this .it is your engine and you will be building it. it sounds like you have not done much hp engines you will have to do more home work and take your time or you will blow up some nice stuff:whacked:
11-14-2005, 04:37 PM
joe bogger

Yes I know just what you mean and no I dont think your a smart ass. I have not built to many high horspower engines in my time. You dont have alot of time to this kind of stuff when your 18 and still in high school. I have been working in the woods for my dads logging company since I could hold a saw. I bought my first truck(1972 chevy) when I was 13 and paid all $2500 of it with money I earned. I have been running that truck with engines I have put together from my own experience and what people have told me. My cusine races circle track and have seen hime build his own motors. I know he will help me and I have been reading things on small blocks for about a year. And have been working to more jobs after school to help pay for this. I realize I will more than likley reck some expensive parts but I am ready to take the leap and build some power. I have to try or I will never succeed. I truly do thank you guys for the help and please dont think I am some board nurd looking for somebody to talk to and just wasting your time. I may not know every thing and need to ask some questions but belive me I will use all of what your telling me later. Thanks again. REALY THANKS!!!
11-14-2005, 05:07 PM
Bryan TTM

joe...before you spend the dough on splayed caps and the machine work....look into a Dart Little M block...not much more $...better oiling...better webbing in the bottom end...more meat in the cylinders...splayed caps or 4-bolt mains(your choice).....you will love the block and it will give you many years of service even with you bangin it
11-14-2005, 05:14 PM
Bryan TTM

you will succeed :)
11-14-2005, 05:40 PM
joe bogger

Well thanks. And I have looked into aftermarket blocks but there like $2000 to $2500 and the machining cant cost that much. I already have several small blocks.
11-14-2005, 05:42 PM
joe bogger

Well thanks. And I have looked into aftermarket blocks but there like $2000 to $2500 and the machining cant cost that much. I already have several small blocks. And I havent heard how much rpm I can handle with stock 4 bolt caps. Like Pat said, I dont even know if I need them. At what point should they be used.

Sorry about the two post I hit the key to fast and sent it before I was done.:LOL:
11-14-2005, 07:19 PM
pat mccarthy

yes the dart block is good. but i would dump your tall deck in it before i would buy the dart block and keep the rpms down on the small block and use better that stock stuff good set of i beams some srp pistons and a good valve train and have fun to line bore and do the caps should be$200to250
11-14-2005, 07:20 PM
erik erikson

Quote:

Originally posted by joe bogger
Thanks guys. Boy I dont think I have to many more questions. How about splayed main caps do they uses special bearing and you have to have the block line bored with the new caps instaled right. I may be running these but dont know much obout them and if I even need them.

IF YOU ARE BUILDING THIS ENGINE FOR STREET USE AND IT WILL HARDLY EVER SEE THE DRAG STRIP THERE IS REALLY NO NEED FOR SPLAYED CAPS.
11-14-2005, 07:56 PM
joe bogger

Pat I have thought about that many times and I want to but I dont know If I can aford to do it the way I want. When I do it I want to go all out. I am going to sit down and figure out how much it would cost for the both of them. And Erik just because it will be street driven dont meen I wont drive it like I am on the strip. If I build something and put the money into it I want it to handle most conditions
11-14-2005, 09:59 PM
techinspector1

See there joe, we have strung this thread to 6 pages. :)
11-14-2005, 10:06 PM
pat mccarthy

i did not help :CRY: :CRY: :CRY: :CRY: :CRY:

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