Rocker Arm Setup for Mild Stroker

[EngineerDoug]

Hello all,

I am planning a stroker build for my 440 block and would appreciate some advice. I will be using the TrickFlow 240 heads on a 500 inch stroker. Cam will be a solid lifter with perhaps 0.520" to 0.550" valve lift. Spring pressures will be maybe 330lbs (open). I see that there are several choices for a complete rocker arm setup, and they vary widely in price.

This will be a street use engine, so I am interested in a rocker arm setup that will not break the bank. I don't want junk, but clearly this is not a high rpm race application either.

Your thoughts/experience? Thanks.

 

[beanhead]

Only my opinion but I like the Mancini/Harland rockers, good parts for the money. True ratios, no roller bearings on the shaft. You can spend more and not gain much other than a fancy name. More serious use/rpm would probably dictate a higher-end set. To get them spot-on they need some geometry setup work like any others, even the higher-buck stuff...that's another issue though as lots of folks just bolt them on and go. BUT check with Trick Flow, I understood that the latest heads have had the pedestals relocated for a better swipe but that may only be with a certain brand of rocker? Sure wish I was sittin' on a pair of those TFs so I could know for sure!

 

[33 IMP]

I would be completely comfortable using the crane ductile iron for your application. Crane says they are good to 550lbs spring. It avoids the various problems with getting the geometry right with roller rockers. I'm using a set on a .557 solid purple shaft.
But man, those are not cheap anymore!
But @beanhead is sure right, I would ask Trick Flow what they suggest.

 

[andyf]

Hello all,

I am planning a stroker build for my 440 block and would appreciate some advice. I will be using the TrickFlow 240 heads on a 500 inch stroker. Cam will be a solid lifter with perhaps 0.520" to 0.550" valve lift. Spring pressures will be maybe 330lbs (open). I see that there are several choices for a complete rocker arm setup, and they vary widely in price.

This will be a street use engine, so I am interested in a rocker arm setup that will not break the bank. I don't want junk, but clearly this is not a high rpm race application either.

Your thoughts/experience? Thanks.

Most anything will work for that application but you should avoid the really cheap Chinese made garbage. If it was my engine I'd probably use Comp steel rockers on there. You'll have to do a little bit of work to make everything line up properly side to side. Don't assume that you can bolt the rockers on and go.

 

[EngineerDoug]

OK I will check with TrickFlow. I had been eyeballing the Mancini kit. Good to know the quality is there, and that's about in the ballpark for what I would like to spend.

Thanks.

 

[493 Mike]

I've had good luck with Hughes products. I have their cam and entire valvetrain in my 493 with RPM heads, solid flat tappets.
Mike

 

[1 Wild R/T]

I too prefer ductile iron rockers.... Seen to many roller rockers fail... Tiny needle bearings floating around are not your friend...

 

[threewood]

Gotta say Hughes. Money well sent imho. My cam is their stl-3842 solid lifter, about .550" lift. Also got the B3R relocation kit to get the swipe narrowed.

And I started with new Crane ductile iron rockers, which wore out fast at the tips.

 

[33 IMP]

Nothing is ever as good as they used to be. My crane ductile are probably 20 years old.

 

[1 Wild R/T]

Nothing is ever as good as they used to be. My crane ductile are probably 20 years old.

My Ductiles are actually Iskys, I have three sets... They have a hardened pad at the valve tip...

 

[33 IMP]

@1 Wild R/T , was that your engine in post #7? If so, what did you think of the beehives? I'm contemplating a set of conical for a solid cam rat motor, and user feedback is always welcome.
And edit: Does isky still sell those?

 

[threewood]

Nothing is ever as good as they used to be. My crane ductile are probably 20 years old.

Agree. Older, used sets are better than the recent ones made. After I found the tip wear, Glenwood checked his as well. Sure enough, his were wearing at the tip too.

For the $450 price, it is better to pay a few hundred more and get something modern.

 

[1 Wild R/T]

@1 Wild R/T , was that your engine in post #7? If so, what did you think of the beehives? I'm contemplating a set of conical for a solid cam rat motor, and user feedback is always welcome.
And edit: Does isky still sell those?

Sorry not my motor.. Never been a fan of roller rockers, just did a search & it popped up... Along with lots of other pictures.... But that one was clearly a Mopar...

I do have two engines with Beehive springs... I've had great results but some folks have had issues... But my stuff doesn't see over 6500 rpm's anymore..

What sold me was video's of valve spring testing on the spintron... Even triple springs start getting weird harmonics at high rpm's the Beehine because the coils are all different sizes doesn't have a resonant frequency...

I wish they had used a better high speed camera for this video... The first part with the white springs are Beehives, the second part is a normal dual spring... They really should have more video of the beehives and they should have shot both setups at the same rpm....

I've seen much better video but I wasn't able to find it this morning..



Second video is higher rpm, turn the volume down.. No footage of a Beehive... But it's pretty interesting how much harmonics the valve springs see... And to tie this back to the original post these crazy harmonics are passed back to the rocker arms....

 

[1 Wild R/T]

@1 Wild R/T
And edit: Does isky still sell those?

Isky quit selling their really good rockers 30+ years ago... They sold re-boxed Cranes for another 10 years but honestly the original Isky's are the best aftermarket Ductile rockers ever made...

They use to be easy to find a swap meets, I never paid more than $100 for a set... Now when they turn up people are wanting $500 or more...

 

[33 IMP]

Thanks @1 Wild R/T ! Those videos are crazy! You would think that much spring movement would just chew the cylinder heads (Or the spring pockets )up!
I remember seeing a test somewhere of a set of beehives on a hyd( cam rat motor, and the beehives ended up giving 500+ rpm improvement due to better valvetrain stability, and the 50+ horsepower improvement that came with it.
I think I just sold myself on some beehives/conicals.

 

[1 Wild R/T]

Yeah, OE manufacturers use them on most modern HP engines.. The Hemi, LS & Coyote all use them... If they didn't do something beneficial OE's wouldn't use them...

 

[rolling_Thunder]

I went with a set of PRW steel rockers on my setup... very mild build with a rather lazy cam in it. Asked my engine builder about the quality of PRW rockers (I have heard stories about pretty much all brands so wanted his input) and his opinion was they are completely fine for a mild build - he runs them in multiple customers' engines and he has not had a problem with them in the years he's been using them.

 

[1 Wild R/T]

I went with a set of PRW steel rockers on my setup... very mild build with a rather lazy cam in it. Asked my engine builder about the quality of PRW rockers (I have heard stories about pretty much all brands so wanted his input) and his opinion was they are completely fine for a mild build - he runs them in multiple customers' engines and he has not had a problem with them in the years he's been using them.

The picture in post #7 is PRW's.. The early one's were junk.. I've heard the newer ones are pretty good...

 

[rolling_Thunder]

The picture in post #7 is PRW's.. The early one's were junk.. I've heard the newer ones are pretty good...

Yes - I've heard the same -- but then again I've heard of even high end arms fail - I had three rocker arms from INDY fail on an engine before... For every one person saying it broke there is probably 1000 people running them with no problem... I decided to find out for myself.

I just couldn't justify $1000 for rocker arms for a street engine

 

[1 Wild R/T]

Yes - I've heard the same -- but then again I've heard of even high end arms fail - I had three rocker arms from INDY fail on an engine before... For every one person saying it broke there is probably 1000 people running them with no problem... I decided to find out for myself.

I just couldn't justify $1000 for rocker arms for a street engine

I agree 100%... But thats why I like the old Isky ductile iron rockers... No much can break & if it does there's no tiny needle bearings to cause bigger problems...

If I hadn't gathered Isky's back in the day I'd probably be running newer PRW's...