Glad you got it tracked down and it's not as bad as anticipated. Did you log it at 5000RPM??? Where you pedalling it or was it bouncing off of rev limiter cause the puffs and decreased RPMs????
C-ya
C-ya
"It Lives"
- Thread starter JOHNBOY
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Smoke rings!! 
Sounded like it popped early in the first pull. Just after the turbo lit. But it is hard to tell on these cheap laptop speakers.
Sounded like it popped early in the first pull. Just after the turbo lit. But it is hard to tell on these cheap laptop speakers.
Well, that's got me worried. I've been up to 5000 before, and routinely run at 4500 (shift rpm)
I've been curious why they use such a light spring to locate the rocker arms longetudially on the rocker shafts. I was going to make aluminum spacers to replace the springs but was told that wouldn't work.
I've been curious why they use such a light spring to locate the rocker arms longetudially on the rocker shafts. I was going to make aluminum spacers to replace the springs but was told that wouldn't work.
More billet goodies!
Looks like the cast rocker stands are not up to the beatings I have planned.:rofl:
thanks for testing
Good to hear Johnyou going to swap the oil pump now too?
Good news that it was top end stuff. FYI, might want to make sure the push rods are all nice and straight. I bent a couple at high RPM.
My log was coruppted because I shut the truck off before stoping the log record. I looked down a the tach needle was stuck straight up on 5.
I honestly could not tell sound wise because all you here in the cab was the big Garrett screaming!Yes that was the ECM limiting as I do not program a limit.
Smoke rings!!
Sounded like it popped early in the first pull. Just after the turbo lit. But it is hard to tell on these cheap laptop speakers.
I think it was broke in the first hook but it still was moving the exhaust valves. I think it pitched the rocker brigde off while I was bring up the rpm the second time.
I honestly think this is my fault. Just the night before the pull I had the valve cover off to adjust the lash because of noise coming from the rockers. I did find the lash was set loose. I now think the bolts that hold the rocker shaft down either, and or both where stretching or loose. That caused the entire works to rattle around. The rocker shaft is very hard and did not like the flex so it snapped. After it snapped the load was not spread evenly on the stand offs and broke them. Which in turn cauesed the rocker bridges to get pitched off.
I remember Superdiesel talking about using grade 8 bolts in his engine for the rocker shaft hold downs. I really think after looking at it that with better fasteners everything would have been fine. ARP studs and flanged nuts are on my list of most does.
Thanks
Awesome is rightAwesome news John!
thanks for testing
you going to swap the oil pump now too?
I need to get a hold of Curtis. I am not sure if I will swap out the pump. I had no issues with oil pressure. 40 psi at idle with 185* water temps.
I checked the push rods. They are fine. They are from EEP they came with the cam. .125 wall IIRC.
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Rockers
Johnboy, If the stand bolts were loose that would do it. Like you said the shafts are so hard they will not flex. If they do they will brake. A buddy of mine was breaking jesel rockers shafts and he couldn't figure out why. I went over and watched him adjust his valves and he would back the rockers off will it was on the lobe of the cam. The spring pressure would crack the shaft then when he run the motor it would pitch the rocker. I bet if you look at all of them good and there not broke they will be fine. Just don't put any load on them when not tight. Jeff
Johnboy, If the stand bolts were loose that would do it. Like you said the shafts are so hard they will not flex. If they do they will brake. A buddy of mine was breaking jesel rockers shafts and he couldn't figure out why. I went over and watched him adjust his valves and he would back the rockers off will it was on the lobe of the cam. The spring pressure would crack the shaft then when he run the motor it would pitch the rocker. I bet if you look at all of them good and there not broke they will be fine. Just don't put any load on them when not tight. Jeff
must be some limit programmed into the FICM, either that or the drivers in it start overheating/exceeding their max duty cycle...just cant make things happen that fast.
sounds awesome tho
glad its something simple, Ive got some extra rocker shafts that Id send you for free .99 if yo uneed them John.
ben
sounds awesome tho
glad its something simple, Ive got some extra rocker shafts that Id send you for free .99 if yo uneed them John.
ben
must be some limit programmed into the FICM, either that or the drivers in it start overheating/exceeding their max duty cycle...just cant make things happen that fast.
That is why I went so big on the injectors. Trying to lower the duty cycle. FWIW my top shot is less than 2000us.
sounds awesome tho
glad its something simple, Ive got some extra rocker shafts that Id send you for free .99 if yo uneed them John.
ben
Thanks Ben I might take you up on that!
Aluminum spacers will work fine. Just use a hardened washer between the aluminum spacer and the rocker arm.
Got to see Johnboy today for the first time in a while; and he brought a box 'O broken parts...
Pretty impressive in the sense that it wasn't a whole lot of parts, didn't cause a huge amount of collateral damage and won't be too much coin to fix.
But it sure as hell sounded bad...:rofl:
Pretty impressive in the sense that it wasn't a whole lot of parts, didn't cause a huge amount of collateral damage and won't be too much coin to fix.
But it sure as hell sounded bad...:rofl:
Ive got a set of these I that I made, took springs out and put aluminum spool spacers and wear shims between...well see....
Attachments
An update. I am still waiting on parts. I got new stuff from GM, ARP studs washers and 12 point nuts from Greg Hogue and rocker bridges from Curtis. Next week will be busy!
More good news. Greg is working with ARP to come up with a stud kit as an actual off the shelf kit!
More good news. Greg is working with ARP to come up with a stud kit as an actual off the shelf kit!
Nice.
Get that thing running by the 12th and I'll bring a steak for you - any cut you want.
The rest of us will eat Brats...:rofl:
Get that thing running by the 12th and I'll bring a steak for you - any cut you want.
The rest of us will eat Brats...:rofl:
