Jesel, Crower, T&D.....

From a Friend. That order if possible...All others Require Talent .....

Main Thing is No Deflection which is Movement...


Steel is to Easy and Doesn't Hurt Rpm as it Doesn't have Nothing to Do with what's RPM'ing

Friends of Friends ...and Reference.
Darin Morgan...

 

Yeah and I believe Brian Tooley Racing has a shaft design for stocker rockers that touches base on this very thing. Deflection.

 

Thicker Pushrods Help with Deflection also .....


No Nothing about BTR rockers .....
If it's like Jesel or Crower is alright.....

Steel don't Move.

If you need or can add a Girdle if Possible to a Stud mount
👍👍👍

But A Real Shaft doesn't need Any Help .....

It's Stable.


Steel.
TX👍

 

I had some luck a few days ago. One of the bolts holding down my yella terra rockers broke right at the bolt head. I n the morning i had an issue with a spark plug lead , put on a spare and all good, then in afternoon it started to miss and i thought electrical.. i fixed a ground wire and started it , still had the miss, no rattles from engine at all. Was still thinking electrical and thought id just whip the rocker cover off, found it then.. Luckily the pushrods didnt foul anything, lucky the exhaust valve was still opening a bit otherwise would have hydrolocked it, lucky the bolt head was sitting on a head stud and wasnt bouncing all around the top end///

 

8mm or 10mm rocker bolt?

 

10mm, ill replace all the bolts while i wait for the crower rockers i ordered to be delivered... I had spare rocker stands at home and while looking for them i found a rocker stand that had a bolt snapped off in it, Id forgotten about that one so mayb i have a bad batch of bolts,,,then again they have been retorqued dozens of times.... Ive had a really good run with the yella terra rockers, minimal wear after 30,000 miles, no visible wear on valve stems....

 

Mick,

I followed your thread from the beginning. If anybody put these rockers to the test, it is you. And they proved their worth.
Can you get Crower shaft system with 10mm bolts?
I thought they were 8mm…

 

Thats a good question. I had my local crower guy send my lifters to the states and organise the rockers, told him what i had but didnt think much past it...
Ill ask him the question about tht.... think crower are behind their end, my rockers have been gone for months, i bought another set so i can driven my car

 

bit of an update..... Ive found the limit of the yella terra rockers... After the bolt snapped , got it up and running , then a few weeks later chewed out the bearings in one of the rockers...
I couldnt get an eta on the crower rockers so gave Mr Mamo a call and he shipped a fresh set of yella terra's for me...
i thought about the YT's, thinking whether i should get them , but really, after 30,000+miles, driving it hard, towing big loads, bouncing it off the limiter every time i get in the car, you cant fault the YT's. Yes i chewed up a bearing but after that many miles it would be on the cards for any brand of rocker to chew a bearing. The rest of the rockers were still good to go, no significant wear that i could see.
In november this year Tony will send me out titanium intake valves thatll swap straight in, ill put the crower rockers on at the same time, Tony also wants to change to a different valve spring which will have a bit less pressure on the seat. Even when i put the crower rockers in , ill stick to valve spring change once a yr, and rebuild the rockers every 20,000miles....
Next for the car is in Feb the car gets new race seats in the front which are getting leather upholstery along with the entire interior getting done, new stereo system will go in and then ill get the car wrapped or painted, still deciding, Other than that im still waiting for the gearbox to blow, the syncros in 3rd a startin to go, pretty good going for a standard T56 which i bought second hand and ive done about 60,000mile

 

Thanks for the update Mick.
I’m curious about gain from Yella Terra to Crower rockers.
I wish you would change one thing at a time to find net gain from titanium valves, but even more so from Yella Terra vs Crower rockers.
There are quite a few threads blaming Yella Terra rockers for top end power loss. Unfortunately no net proof as people were doing other upgrades along with rockers before going back to dyno.

I’m still curious if your Crower rockers will be 8mm or 10mm bolt style.
If Crower doesn’t offer 10mm bolts, I will not upgrade MMS TFS heads to 10mm style when time comes, because I plan to use Crower rockers instead of Yella Terra.

My 434 block is still at RED. Once the short block is ready, I will focus on top end. I’m not there yet, so I don’t inquire about bolt size myself.

 

Ive read most of the threads blaming the YT rockers or Mamo heads for any engine woes. The funny thing is none have made any significant gains changing heads or rockers, most lost hp.
My limiter is set at 7200rpm and I’ll bounce off it everyday. It’s always revved smoothly to that

when I broke a spring, which damaged the cam that wasn’t the heads or YT”s fault, was my own, to busy building holiday shack and not keeping up on the maintenance. The bearing going is just one of those things. I’m pretty happy really, after getting so many miles out of the setup .
Also I discovered I don’t hv the 10mm upgrade, so no problems using crowers.
what I’ll do is when I put the new springs n titanium valves in I’ll dyno test with the yt rockers, then change them out and run it up with the crowers.
Its been a learning curve running solid roller on the street in regards to maintenance, I took it to the limit, found the breaking points

 

Following this thread it is clear you pushed all parts to the limit.
I spoke with Tony regarding Yella Terra rockers. I don’t believe they are responsible for power loss at the upper end. 10mm bolt upgrade add some stability.

That said I’d like to see how Yella Terra will do against Crower rockers.
Looking forward to see your results Mick.

 

I have a question for you, or forum member who might know: Would going to a 10mm bolt instead of the 8mm weaken the boss holding the rocker? Seems like it may be a trade off. We're the 10mm bolts ARP, or?? It would seem fatigue/cycles are what broke the bolt. A 10mm bolt made of quality steel is pretty tough to break......

 

Tony sells his MMS TFS heads with 10mm bolt upgrade for the last 4-5 years.
Nobody reported failure yet.

 

So ive been chasing an oil leak for the past week, whenever it gets over 4000rpm i get a smell of burnt oil and a puff of smoke.
I pulled the oil cooler lines off 3 times re-doing the fittings thinkin it was that. Was still having the same problem.
I couldnt see any oil inside the bell housing but was thinking there was no where else it could be but for the rear main seal.
Was just about to pull gearbox n i thought id have a close look over entire engine . There was a tiny oil droplet on the dipstick tube where it ties back to the head.
Turns out theres a crack in the tube , which was slowly letting the oil run down the block and when giving it some revs would burn off on inside of extractors... found the bastard.
I hate pulling the gearbox

 

Good to see you are still updating the thread.
Hope all is well.

 

Good to see you here as well, Bortous! How are things with you?

 

alls good mate.. whens your next project ?

 

So next on the list to replace is clutch. Im running a mantic twin ceramic clutch and now i need to either get new clutch plates or upgrade to a mantic triple plate.
Obviously the triple will be heavier , just wonder how it will affect how fast itll spin up

 

I would also check the end of the input shaft for wear. Normally you want .003 or less between the input on the bearing. On a stock LS the shaft is like .589 and pilot
bearing is like .590 or so. I just measured mine and it was down to .577 so a little too much wear. The last thing you want are your new clutch plates wobbling around.