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I missed the first part of the discussion, what's the problem?

BTW I bought a USED set of those Energizer rockers for the 289 about 12 years ago, been working great ever since, hundreds of blasts up over 7000RPM with a 282S solid lifer cam. I can say that I'm slightly concerned, and plan to buy a nicer, lighter weight set someday, probably the lighter weight Scorpion Platinum series, which are still under $300.

http://www.summitracing.com/parts/SCC-SCP2017/
 

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Discussion Starter #4
Wether or not 1.7 BBC rockers are good enough to run on a 335 series or bigblock Ford, with saving a little cash in mind.
 

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Wether or not 1.7 BBC rockers are good enough to run on a 335 series or bigblock Ford, with saving a little cash in mind.
sad part I agree with you . Only if you are a low end user and saving money is more important THAN RIGHT
 

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Wether or not 1.7 BBC rockers are good enough to run on a 335 series or bigblock Ford, with saving a little cash in mind.
I still feel it would be better to get a set of gently used correct roller rockers than use new rockers for the wrong application.
 

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Has anyone actually measured the "wrong" rockers compared to the "right" rockers to see if dimensionally there is really any difference? Has anyone tried and confirmed you can't acheive proper geometry with the "wrong" rockers?
 

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Discussion Starter #8
sad part I agree with you . Only if you are a low end user and saving money is more important THAN RIGHT
How much is being "RIGHT" or "correct" worth? How much power? How much longeviety? How much more right can my extra money guarantee? How often do manufacturing standards allow for a "standard" deviation? You may pay extra for "Ford 1.73 rockers" and get a BBC 1.7 just because most people dont check their rocker ratio before they install and the MFG can get away with it until someone calls BS on them... Being "right" isnt worth my extra money personally...I plan to buy a set of 1.8 ratio rockers down the road, if i can confirm that they wont detonate upon instalation that is...and guess what...they dont make em for a 400 ford...so far as i know at least...

IDK if anyone has measured them, i couldnt afford to buy two sets and measure them myself...return shipping alone would cost you 40 bucks if you wanted to measure the difference in two new sets right now, and then send them back...maybe theres and engine builder out there who will chime in with out a biased opinion and just present facts...I have only two facts at my disposal...They are listed as interchangable at a certain price point...and I have them on my running, very strong engine right now. Anyone else have any facts to present?

Disclaimer for this post: My tone is intended to be humorous, not a know it all smarty pants jack ass;)
 

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The BBC rockers have similar ratios and will physically bolt on, but don't fit properly due to different geometry and distances to tips and centerlines... Get the correct parts to begin with.... JMHO...
 

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Discussion Starter #10
The BBC rockers have similar ratios and will physically bolt on, but don't fit properly due to different geometry and distances to tips and centerlines... Get the correct parts to begin with.... JMHO...
How much different? The geometry is the ratio, correct? Its clearly different, but different enough to be detramental?
 

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How much is being "RIGHT" or "correct" worth? How much power? How much longeviety? How much more right can my extra money guarantee? How often do manufacturing standards allow for a "standard" deviation? You may pay extra for "Ford 1.73 rockers" and get a BBC 1.7 just because most people dont check their rocker ratio before they install and the MFG can get away with it until someone calls BS on them... Being "right" isnt worth my extra money personally...I plan to buy a set of 1.8 ratio rockers down the road, if i can confirm that they wont detonate upon instalation that is...and guess what...they dont make em for a 400 ford...so far as i know at least...

IDK if anyone has measured them, i couldnt afford to buy two sets and measure them myself...return shipping alone would cost you 40 bucks if you wanted to measure the difference in two new sets right now, and then send them back...maybe theres and engine builder out there who will chime in with out a biased opinion and just present facts...I have only two facts at my disposal...They are listed as interchangable at a certain price point...and I have them on my running, very strong engine right now. Anyone else have any facts to present?

Disclaimer for this post: My tone is intended to be humorous, not a know it all smarty pants jack ass;)
your disclaimer / being humorous doesnt work . reason why is you know all about (you think) the cheap fits all rockers

now there is three telling you BBC rockers dont fit correct .

they do have 1.8 ratio for the 400 , Crower , Comp Cams has them , then there is the big dollar shaft rockers by Jesel and T&D with several ratios

good engine building is not a place for smarty pants people / jackasses , for they might do it wrong
 

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Discussion Starter #12
Im not claiming to know it all, im humble at worst. But, I dont take things on face value. I wasnt sure the rockers i bought would work, but I tried it, they worked. YOu still havent proven to me im wrong. Im doing my best to be nice and open minded, and learn from someone. Telling me its wrong doesnt teach me ****-telling me EXACTLY why its wrong-with numbers does teach me. If you cant do anything except tell me im wrong-then you cant be right..
 

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I started building C motors when they first came out. 385s too. Back then all that was available was BBC roller rockers for them listed as for a Ford.
Caused lots of issues. Most didnt notice. Measuring lift, seting up pushrod lengths, having to have custom cams made to get some of the desired lift and such. Pushrod woles needing massaged to clearance pushrods.
They have dofferant geometry than a BBC ...even more interesting Ford canted valve heads because of the differant geometry of the intakes and the exhaust realy need spacific rockers for intake and exhaust.
 

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Im not claiming to know it all, im humble at worst. But, I dont take things on face value. I wasnt sure the rockers i bought would work, but I tried it, they worked. YOu still havent proven to me im wrong. Im doing my best to be nice and open minded, and learn from someone. Telling me its wrong doesnt teach me ****-telling me EXACTLY why its wrong-with numbers does teach me. If you cant do anything except tell me im wrong-then you cant be right..
you don't take things at face value !!!! you did and still are on the fits all rockers

screw what rockes are right ... FIRST learn how to set up a valve train correct .

know you can put the front runners on the rear of a drag car . does that make it .....?
 

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Effectively the difference or "bad fit" would have to be the distance between the rocker tip and the pushrod hole. The ratio is just where you locate the pivot relative to the two ends. I suppose the distance from the center of the pivot to a line drawn between the roller tip and pushrod hole would be the second place you could check for a mismatch, but I'm betting that dimension is extremely small, if not directly through the center of the pivot. How much these measurements can vary before you get into trouble, I don't know, seems the best telltale is if you can get proper rocker geometry and still have the roller tip at the centerline of the valve.
 

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Effectively the difference or "bad fit" would have to be the distance between the rocker tip and the pushrod hole. The ratio is just where you locate the pivot relative to the two ends. I suppose the distance from the center of the pivot to a line drawn between the roller tip and pushrod hole would be the second place you could check for a mismatch, but I'm betting that dimension is extremely small, if not directly through the center of the pivot. How much these measurements can vary before you get into trouble, I don't know, seems the best telltale is if you can get proper rocker geometry and still have the roller tip at the centerline of the valve.
nothing to do with roller tip to push rod cup .

where the push rod cup sit , sets the ratio .

fulcrum length and cup angle and center heights are set for the head
 

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Actually the only thing that remains fixed is the fulcrum. After certian changes everything can get out of wack. Usally it because of too much lift. Factory stuff is designed to a certian lift point which accomidates so much either side of that point. After that point a new design rocker might be required. In reality we have to purchase some most cant design there own. Fixes can be had by changing vales lenghts and or pushrod lengths.

Say like a BBC rocker on a ford. roller tip might be about right spacing but its position vertically to the valve tip is off. This causes the rocker to be at half travel valve closed. With enough lift the pushrod side of the slot in the rocker will hit the poly lock. The rocker with valve closed is were it should be at half lift. Fix might be a longer valve tip to rotate the rocker. Then the pushrod might need lengthened the rocker moves further up the stud. Might even need longer studs. Eventually this screws with the rocker design even more.
Kindof stuff found when one checks the lift at every valve during assembly.
I used to design valve trains. Spent a lot of my time correcting stuff CAD operators didnt understand because they were just CAD operators. Many didnt know how to change thier own oil.
 

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The BBC rockers have similar ratios and will physically bolt on, but don't fit properly due to different geometry and distances to tips and centerlines... Get the correct parts to begin with.... JMHO...
right on. a friend had a shop rebuild his 70 boss 302 engine. he had problems with the valve train. the shop told him it was his problem. i had him take it to JGM and it was discovered that bbc rollers were on it. the ratio is close but the physical deminsions of a bbc and ford c rocker are different. JGM said they have seen this many times during the 30 years they have ben building ford engines. he showed us a bbc and fc roller rocker side by side. yes they are different. btw i also found out that you cannot use compcams(or other brand) 1.7:1 289 type ford rockers on a ford c head and visa versa.
 

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right on. a friend had a shop rebuild his 70 boss 302 engine. he had problems with the valve train. the shop told him it was his problem. i had him take it to JGM and it was discovered that bbc rollers were on it. the ratio is close but the physical deminsions of a bbc and ford c rocker are different. JGM said they have seen this many times during the 30 years they have ben building ford engines. he showed us a bbc and fc roller rocker side by side. yes they are different. btw i also found out that you cannot use compcams(or other brand) 1.7:1 289 type ford rockers on a ford c head and visa versa.
this has been told about the BBC rockers . Boss302 , high RPM , the problem shows up quick
some want to belive its ok and use bbc .

W rockers on a C , works great if you want to push the valve open by the retainer . some might want too. LOL
 

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this has been told about the BBC rockers . Boss302 , high RPM , the problem shows up quick
some want to belive its ok and use bbc .

W rockers on a C , works great if you want to push the valve open by the retainer . some might want too. LOL
Makes the valve tip last longer that way, right? :)
 
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