NEMESISVETTE

iTrader: (2)

Ive got a tech Question here guys. Ive searched and called a few tech lines and seem to get mixed answers to this Question. My Short block for the past 2 years consisted of a LS6 block, stock crank , eagle H beam rods and diamond -2 pistons.. Been a great combo made 438rwhp on motor and 710rwhp on a 275 shot. It had Clevite P bearings in it has ran great. Now its winter and time to change the rings that where in it for a set of total seal nitrous friendly rings (steel top ring) and be a bit more generous on the gapping. Looking to spray a 300 wheel shot, and not second guess it.

Now with all that said the motor did great with the 275 shot on the Clevite P bearing but noticed on tear down a little copper at the 12 o'clock on the rod bearings. Again no problems with the motor before tear down.
Now I have spoke with Texas Speed and they shipped me some replacement P bearings, but my Machine shop guy wants me to use the H bearings.. So thats when I started searching for a answer. Texas speed told me the H bearings wont work on a stock GM crank, but Ive found some that have done it.

I did PM Tony M and he gave me some good direction and I appreciate his advise.. Im making this thread for a definitive answer on this Question. I trust the guys at Texas Speed but need to hear from other engine builders on this. This car was making over 700rwhp on the P bearing but looked stressed.. Can I run a H bearing on a stock Crank?

KCS

iTrader: (20)

I don't see why not.

I've used H series rod and mains on stock cranks several times. I think it's when you use a P series on an aftermarket crank that you may run into problems. I haven't seen it firsthand, but I have heard that the P series isn't chamferred for the radii on an aftermarket crank where the journal meets the cheek. That's not a problem with an H series since it's meant for a radius and the stock crank has a rolled fillet.

Clevite H series main w/ stock crank:

NEMESISVETTE

iTrader: (2)

Thanks for the response.. I was beginning to think I posted this Question in the wrong section...lol. I want to run H bearings, but am told by TexasSpeed I cant.. Now they shipped me the P bearings knowing this car will be making 800rwhp.. , and assured me that the H would NOT work.. Seeing your pic I cant see why they wouldnt work..
Here is a pic of my Eagle Rod with my old Clevite P bearing that has 8,000 miles on it and many 275 shots of Nitrous on it.. Making over 700rwhp.

The BLUE arrow shows copper just starting to show at 12 and 6 o'clock.
The Red arrow shows that my Eagle rods have a rolled fillet and no issue running that rolled fillet on a stock crank.?

KCS

iTrader: (20)

Yeah, I'm pretty confident that the H series will be just fine. I just don't see any reason why they wouldn't work, and I haven't had any problems using them already.

What were you running for bearing clearance?

SilverSS

iTrader: (30)

H series and stock crank will be fine. My motor was built at SAM Racing using H series bearings and a stock ls1 crank. They know their stuff. I would use these over "P".

09camaro383

iTrader: (2)

I have H series but im running a aftermarket crank I was told that they were designed for forge steel cranks and to run P series was a no no!! I never heard you cant run it the other way around stock crank and H series!! but they are a little different.... I will just run the P series you know it works so why experiment!!

NEMESISVETTE

iTrader: (2)

I wouldnt say it "worked".. It did but it didnt. Look at the pic in post #3. The Blue arrow shows a bit of copper beginning to show. In a way you can say it worked becouse I never had any failer before desiding to freshin up the motor to make it more Nitrous friendly.

Sure these bearings worked with the 275 shot but for how long? Now I wanna step the shot up and have the upgraded rings to do so, the ARP head Studs to do so (replacing the ARP head bolts for Studs), Copper sealing the Cometic gaskets this time to. So why would I just go with the P bearings becouse they worked OK.. Just like I asked texasspeed, I wanna run the harder H bearings for added insurance. ,, but was told I Can'T run the H bearings. So they shipped me P bearings. Well Now im seeing I may be able to run the H bearings and if I can,,,, I want to.

NEMESISVETTE

iTrader: (2)

anymore thoughts on this?

NEMESISVETTE

iTrader: (2)

anymore thoughts on this?

Gonoma

iTrader: (15)

who is your engine builder?

NEMESISVETTE

iTrader: (2)

Just got off the phone with Kurt (username 427). I cant thank him enough for taking the time to answer my nagging Questions so early in the morning.lol Very nice imformative LSX Guro.

Gonoma

iTrader: (15)

what did you find out? I'd like to know as well for my build while this subject is being discussed if you don't mind

Jon@Texas-Speed

iTrader: (18)

You can absolutely run an H-series bearing on a stock crank. We just typically run the P bearing on stock cranks because most aren't making the kind of power you are looking for. If you want a H bearing in your motor or setup, we can definitely do that. I think there might have been some kind of misunderstanding on this but just to clear it up, yes it can be done.

Jon

Snyper

iTrader: (27)

Jon, what do you think I should use for my setup? Stock crank, forged rods/pistons and 20psi(88mm). Id rather spend a little extra now if im better off. I plan on daily driving my car and beating the **** out of it on a daily basis.