Motor won't rev over 5200-5300rpm... WTF???

Never resolved mine either... it still does it at 5500 to 5800 and has a lil stumble at 5200. Saving money to change lifters, springs and possibly cam. Im so disgusted with it that i just parked the gn for winter and not going to touch it to spring. Even thinking about it pisses me off
 
Update......new custom grind hyd roller cam, morel short travel lifters, pac 1209x springs/locators/retainers/locks fixed the issue, have revved it to 6400 no issue and pulls clean and strong up top. Upon tear down I found that I had 3 bad lifters. These were morel reg travels and the cross pin retention in the foot of the lifter had failed and was causing the lifters to drag in their bores. They did a pin retention design change 5ish years back and turns out I had the fail prone design. The TA springs could use a better selection of some of teh newer design features and lighter retainer. Fwiw their fix using stronger springs out of their catalog would require my very expensive T&Ds to be machined to clear an even bigger OD spring.....uhh no!! I have sent all the spring and hardware info to Nick Micale per his request as Kenny D just bought a set of TA heads and had the same not wanting to rev issue and hopefully they can send the heads out better equipped from now on. Clearly my bad lifters aside they dont put strong enough springs out with the heads. Granted the pac 1209x springs are too much for regular travel morels since....iirc they dont want over 350 lbs open. But are fine for short travel and as far as noise....they sound a lil more sewing machine but im not the typical turbo regal whine about exh drone and valve train noise diva like most [emoji1]
Very frustrating and alot of money and time wasted but glad its fixed.
 
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Bad lifter
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Mine car is at Nick's now so I'm going to get my issue figured out as well. Thanks for the update. What can are you running now?
 
I put my new spring in and the first 2 times it rev'd to 6k no problem. Took it out again and got it nice and hot, then it would do the same thing at 5300.
Now the springs didnt do it. 190/460 but I have 853 comps. Do I need new lifters now?
 
Im wondering if the lifters are pumping up at higher RPM's when cold and not when hot. Oil viscosity was way thinner the last time out because it was heat soaked. I may go with the VR1 50 weight and see if that changes anything. If it does, then I know its lifters.
 
Im wondering if the lifters are pumping up at higher RPM's when cold and not when hot. Oil viscosity was way thinner the last time out because it was heat soaked. I may go with the VR1 50 weight and see if that changes anything. If it does, then I know its lifters.
What oil was in it before? I guess the thinner oil may bleed down better and help with lifter pump. I remember that most hyd lifters should pull to 6000. Trouble happens after 6000, not before.
 
What oil was in it before? I guess the thinner oil may bleed down better and help with lifter pump. I remember that most hyd lifters should pull to 6000. Trouble happens after 6000, not before.
6000+ isn't a problem with the correct lifter. Who needs to be over 6000rpm with 99% of what you see posted on these forums? 6000+rpm is mid 9's or faster!
 
6000+ isn't a problem with the correct lifter. Who needs to be over 6000rpm with 99% of what you see posted on these forums? 6000+rpm is mid 9's or faster!
So, what do you suggest?
It didnt hurt me to try the 853's that were already in there. They worked before, but now there is a lot of spring pressure. Now I need to take another step forward and I am thinking new Morel short travel's with new push rods. I really need to do it anyway. My goals are mid 9's.
 
I've covered valvetrains extensively here many times. I even posted detailed pictures of what it takes to make do with iron heads which don't have a lot of room to work with. If you want the lifters and springs that can take the pressure and will work with most lobes you can message me.


Sent from my iPhone using Tapatalk
 
I've covered valvetrains extensively here many times. I even posted detailed pictures of what it takes to make do with iron heads which don't have a lot of room to work with. If you want the lifters and springs that can take the pressure and will work with most lobes you can message me.


Sent from my iPhone using Tapatalk
Pm'd you
 
UPDATE:
I fixed this issue with Solid rollers.
My spring pressures were too great for the 853's to handle. They were bleeding down at 5100-5200 rpm.
I can spin it to the moon with or without boost. It pulls hard past 6k rpm now.
I would like to specially thank Bill at Weber Racing Engines and fastblackracing on the board here.

Time to go racing now.
 
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