Btw I never said going from 6800-7k was a greater increase in stress then going from 6k-6800 I have no idea why you think I said that. I simply said 6800-7k is a big jump in pressure.

 

I talkd to a ARP dealer yesterday afternoon and he has ARP factory replacment rod bolts in stock. So again the whole resizing thing doesnt make sense. You say they have to be with ARP, ARP says they dont. Tit for TAt back and forth, and still no one has explained in detail

Why resize? whats the porpouse? does something change in the rod ends when putting in new bolts? or is it directly related to the bolt hole it self that brings on this need for resizing?

 

When you change rod bolts it changed the clamping force on the rod cap which can distort the cap changing the clerance the rod bearing has. if it causes a tight spot you'll spin a bearing soon after. Katech says because there bolt is.like factory resizing is not needed but with anyrod bolt change the rod ends should be checked to make sure there not out of round.

 

Thank you

 

ARP's don't require resizeing. It's a internet myth...

 

No even arp says they should be resized

 

You just said they don't break unless theres another problem or if the bolt is defective, which is what I'm disagreeing with.

At 6500 RPM, the rod tries to pull the bolts apart roughly 108 times per second. If that force is enough to stretch the bolt, it won't take as long as you may think to develop a crack and come apart. Once that crack starts, it will literally take a fraction of a second to spread and split the bolt in two.


Yeah, I'm really just sick of these threads, I really just don't bother anymore. At this point, if someone really asks why you should resize with ARP's, they're just too incredibly lazy or stupid to search for the answer.

I rest my case. LOL

 

Ill take your word on the rod bolts breaking I always see them stretch first. The person who posted his broke ended being at 7100rpm at the time so his very well might have just snapped.

I know you don't have to resize them but to be 100% sure they should be. Lots on people get away without it though

 

ARP got blamed for problems when shade tree's that had never dealt with a fractured rod fucked them up... Hence the internet myth.

 

Please explain? I was under the impression cracked rods could only be put together one way because the cracks where different on every rod?

 

ARP states very clearly in their instructions that you need to resize these LSx cracked cap rods, just like the ARP instructions for the old rods that these shade tree mechanics may be more familiar with. Its not a myth, its just people being lazy and cheap.

 

thats funny their tech line told me they added that disclaimer to keep them from being held liable for installer error, and it wasn't required.

Ok, then whats so mystical about the katech that they don't require resizeing?

 

ARP told me pretty much the samething
Thats what im wondering about katech too?

 

I just talked with a very reputable vendor in the LSx world from this site. And thier opinon is that the stock rod bolts are fine in the 6800 rpm range. Now im not going to name names and throw up direct quote because i didnt ask their permissiom to do so but i trust their word on it

so flame away if you must...

guess thats what i get for asking the general population and not talking to the pros first

 

install error???

if someone doesnt follow the directions, its their own fault. not ARP's. i know from first hand experience that a cracked cap LS1 rod with ARP bolts will distort the big end...in my case it was .003's average over 8 rods. some more, some less. thats pretty fucked considering factory oil clearence is only .002-.0025. therefore, 45* from the split of the rod and cap, i had no oil clearence, and right at the cap fracture, i had excessive...

thats why my bearings were trashed in 1k miles. im not saying this is the case in all sitiuations, obviously because there are people running 10's of thousands of miles on ARP bolts without resizing.

also, in the matter of spinning a bearing because of bolt stretch, or catastrophic failure due to the same thing...im not leaving it up to chance. in my personal opinion weather or not anyone wants to follow suit, ill remove the engine and install the rod bolts properly and remove all doubt on weather or not my rod bolts will hold if i move the stock RPM range for one reason or another. even if its just removing the pistons and rods, and replacing bolts and rod bearings and leaving mains, rings and cam bearings alone. because in my opinion, if your moving the rev limiter up, you obviously have a cam. thats the only reason to move it. so if you have a cam, you obviously have a good chunk of change wrapped up in the cam and supporting mods already, so why would you cheap out on rod bolts? you take your time and make sure the cam is setup properly so it wont fail you but you leave the bottom end to a crap shoot. who knows if it will hold or not? nobody does. i dont care what the "experts" say, its still a crap shoot.

if your not going to do rod bolts with a cam, then you may as well just stuff the cam in there, not worry about an oil pump or timing chain...dont worry about pushrod length or vavle springs either, because your bottom end is a crap shoot so the rest of your build may as well be too.

 

^^^^still waiting for an answer on this part...

 

Katech manufactures their bolts to exact OEM specification with stronger material. the bolt does not exert any more clamp force than the stock bolts, they just resist stretch and distortion better than stockers.

 

OK during a cam swap your right at the timing chain and the oil pump. So you should always change to atleast an LS2 chain because there much stronger. If you have an ls1 oil pump they suck so you should upgrade to an ls6 oil pump.
If you have a low mile ls6 pump already your fine there's no reason to upgrade really.

The thing the makes rod bolt's different is you must pull the engine and tear it down according to you to do it correct. If you don't tear it down you run the chance of spinning bearings.

BTW the newer rod bolts don't have the horrible rep that the 98-00 rod bolts had.

 

i understand the timing chain and stuff is right there when your doing a cam, but what im getting at, is your already going that far, and spending that much money, why risk all that time and money spent on that when your going to skimp on rod bolts.

and honestly, ive found it easier to just drop the entire engine and K-member do the cam and head swap while its out and re install it. its easier to change valve springs if your not removing the heads, and you can do rod bolts correctly.

ive found it easier to drop the engine to do what i need to do to it, than work around the cramped engine bay of an F-body. of course thats personal prefrence and ive had the engine in and out of enough cars, i can have it out and on the stand in under 2 hours. considerably longer installing it making sure everything is right where it belongs, but its well worth it, esp if i break a bolt or lose something down one of the bores.

 

I can agree with what your saying but Ive already installed my cam and heads so I have no good reason to tear the engine down. If I had my engine torn down already I would for sure install ARP or Katech rod bolts just in case I ever wanted to rev over 6800rpm and for extra insurance as you like to say. But I cant see tearing the engine down completely just to install rod bolts for a car that has 6800rpm rev limit. Like I said my shift point is 6600 anyways so the only time it will see 6800 is when I shift slow. I think for a car like mine the 01 bolts can handle the job with out problems. But for anymore rpms then mine I would invest in rod bolts.