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Ok, i put in some 1.6 roller rockers from a 3.0 v6 and now my engine wont start, it just spins over like there is no spark plugs in it.... and there is!! im kinda confused as someone said b4 on here that these where a bolt on upgrade, does anyone have some input on this PROBLEM... :character0056:
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Ok, i put in some 1.6 roller rockers from a 3.0 v6 and now my engine wont start, it just spins over like there is no spark plugs in it.... and there is!! im kinda confused as someone said b4 on here that these where a bolt on upgrade, does anyone have some input on this PROBLEM... :character0056:

 

sounds like the valves are being held open. Is it a stock cam? I've heard of guys installing roller rockers on stock cams but I've always wondered how it worked. Roller cams always have tiny base circles because the high ratio rocker would keep the valve open otherwise.

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I believe it is a stock Caravan cam?? it has adjustable screws on the rockers that came off of it... where can i get a roller cam?? can i go pull one off a vehicle or do i have to order one?? any input is very appreciated, Dvenable told me that the problem is the valves are being held open as well, and i believe him, but would like to know what cam i need... is it a magna cam?? and what vehicles had the cam i need? And if my valves got bent, im going to go find the ebay guy that says this is a bolt on upgrade and kick his a$$!! Does anyone know if there is enough clearance between the piston and valves?? im really hoping my new njv-head has not been ruined from my believing that :deadhorse:
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If you had a hydraulic lifter vales and cam i am told it should have bolted on. There is some debate as to weather rollers are an up grade or not, especially with a stock cam. I run in the 13 teens with the adjustable lifters. If your on a budget put the stock adjustable lifters back on. A roller cam head is best set up by a machine shop.The money you would spend is better spent elsewhere if your car is mostly stock.

 

Tim C or http://schneidercams.com/page-not-found.as...com:80/shop.htm sell roller cams.

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I believe it is a stock Caravan cam?? it has adjustable screws on the rockers that came off of it... where can i get a roller cam?? can i go pull one off a vehicle or do i have to order one?? any input is very appreciated, Dvenable told me that the problem is the valves are being held open as well, and i believe him, but would like to know what cam i need... is it a magna cam?? and what vehicles had the cam i need? And if my valves got bent, im going to go find the ebay guy that says this is a bolt on upgrade and kick his a$$!! Does anyone know if there is enough clearance between the piston and valves?? im really hoping my new njv-head has not been ruined from my believing that :deadhorse:

 

 

Could be that you had the arly longer valves, be carefull with rollers, It can cause your retainers to hit/damage the valve seals or even coil bind the springs.

 

Rollers will either work or not work- in your case they did not so take them off and go back with what you had.

 

Dad

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i just installed a set yesterday on my marnel head and ??? cam (sounds a little lopey, came with my parts car). but mine seemed to work fine. it has less of a clattering sound now. i made sure my lifters (hydrolic) were good when i intalled them. not sure if this helped but it seemed to be the same kind of situation.
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i just installed a set yesterday on my marnel head and ??? cam (sounds a little lopey, came with my parts car). but mine seemed to work fine. it has less of a clattering sound now. i made sure my lifters (hydrolic) were good when i intalled them. not sure if this helped but it seemed to be the same kind of situation.

If you put them on mechanical rocker shafts yes they will be noisey cause they aren't getting any oil and to use those rollers with the stock valves you end up with a LOT of clearance under the lifter and the valve isn't opening and closing when its supposed to from that and no I doubt the car will start and if you test your compression it will be very low that's why Tim was giving out little WASHERS to stick in under the lifter to use those damn roller rocker arms with stock valves and it makes your head so damn loud, eventually the washers get moved around and ate up, blocks the oil flow or even break the end from the rocker arm -which happened to me on TWO different heads. If you want to use those roller rocker arms you absolutely MUST have the NON U.S. ROLLER CAM PERIOD to go with them. Take the roller rocker arms back off and THROW them in the trash can, worn out crap anyway and the one that started selling those years ago should be slapped and they are still selling them. The only way you can use roller rockers on this motor is to also use them with a ROLLER CAM. Your valve timing gets all screwed up if not and that makes for a big DOWN GRADE

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going to roller rockers is a great idea, it does how ever have a few draw backs and one big one is YO CAN NOT DO SO ON A SLIPER STYLE CAM and the use of a roller grind cam is a MUST , but with the proper set up and right cam it frees up a good bit of so call'd free power

 

and for the 10 millionth time,, you MUST colapse the hyd lifters when/before installing them in the head

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1.6 roller rockers, Roller cam, Stock length valves.......... No spacers, No workie!!!! With the proper spacers... Three years now, no problems. Contact Tim C. on this site if you want info. on Roller set ups.

 

CALIBER 308

Edited by Caliber308
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going to roller rockers is a great idea, it does how ever have a few draw backs and one big one is YO CAN NOT DO SO ON A SLIPER STYLE CAM and the use of a roller grind cam is a MUST , but with the proper set up and right cam it frees up a good bit of so call'd free power

 

and for the 10 millionth time,, you MUST colapse the hyd lifters when/before installing them in the head

 

hate to diverge from the OT but shelby do you think the roller could also increase gas mileage? I've been daily driving my yellow car occasionally and the fuel pump is about to quit so I've really been limping around off boost just as mode of transport. I imagine that's a big reason the gas gauge won't move too but this thing will not burn gas.

 

I think if I converted to non-assisted steering it might get 30+mpg.

Edited by chiplee
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Roller rockers do two things:

* because of the shape of the roller vs. a slipper, the cam lobe can be more aggressive in opening & closing the valve so you get more net duration for the same total duration time. That means better breathing = more power

 

* Rollers have less friction than slipper setups... (which is why they can be more aggressive in the opening & closing slopes) so there is less internal engine friction = slightly better MPG.

 

Internal friction is why a V8 gets worse MPG than a 4 cyl motor pushing the same car at freeway speeds. Both engines are producing pretty much the same horsepower/torque at the wheels (same car, same speeds, so same drag coefficient and weight => same power needed) but that V8 has twice as many valves and piston rings making friction. Running the V8 at a much lower RPM helps counteract that - friction losses increase with RPMs. Even with lower RPMs though having twice as many moving/friction-making parts ends up costing MPG.

 

Other things that eat horsepower:

* oversize water pumps. Ideally you'd push "just enough" water to keep the engine temps correct. Unfortunately that "just enough" varies with engine speed, outside air temps, driving speed, etc... so the water pump and cooling system are designed for the "worst combination" possible. Most of the time it's oversize and the water pump is sucking down twice as much HP as the cooling system really requires at that instant.

 

* thicker oil - it takes horsepower to push oil through the engine, thick oil consumes more HP.

 

* thicker tranny or differential oils too.

 

* running a too-cool thermostat: the heat dumped out the radiator (or out the exhaust) represents energy from the gasoline that did NOT become crankshaft torque.

 

* Other friction: bearings on the V-belts, power steering pump, etc.

 

mike c.

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just to expand on the too cool engine coment,, driveing to work on the free way and going down a 1/4 mile drag strip are two very diff things and require diff things , also what the dash temp gauge says and what the temp actualy is at diff area's in the engine and head veary a great deal for example the coolant may be 190 f at the thermostat but in another spot it may be 210f or over ,, engines are not the same temp in all area's , the temp sender is only reading the coolant at it's location
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hate to diverge from the OT but shelby do you think the roller could also increase gas mileage? I've been daily driving my yellow car occasionally and the fuel pump is about to quit so I've really been limping around off boost just as mode of transport. I imagine that's a big reason the gas gauge won't move too but this thing will not burn gas.

 

I think if I converted to non-assisted steering it might get 30+mpg.

 

:) i see your finding there is gold in that there ol man driveing

i'm geting over 30 mpg doing that with a slip rocker cam but i almost never see 60 mph all county 50 or 55 mph roads with a lot of 45 mph streets in there ,, with a mild roller cam i beleave i could see 35 mph

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So to recap. ROLLER ROCKERS ARE NOT A BOLT ON PERFORMANCE PART FOR THE STOCK CAM. They change the valve opening and closing timing for the worst.

 

So it seems like a lot of people want to use them, so why hasn't anyone on these boards used a stock magna roller cam & roller rockers?

Considering the good HP & TQ numbers made with the stock cam, I think a stock roller magna cam and rockers could be a good upgrade.

 

I still haven't even seen a pic of the magna roller cam. I would really like to see someone who has the means, test one out.

And I would also think a cam with a stock roller profile would be a better staring point for a performance roller re-grind than a slipper cam, more meat in the right place, I would think. :confused0024:

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And I would also think a cam with a stock roller profile would be a better staring point for a performance roller re-grind than a slipper cam, more meat in the right place, I would think. :confused0024:

 

Want the answers?? Contact Tim C. on this site.

 

CALIBER 308

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Want the answers?? Contact Tim C. on this site.

 

CALIBER 308

 

He is free to join the conversation, but I'm not looking for just his answer. He provides a valuable service and I appreciate that, but I'm not convinced that only one person has all the answers.

Roller cam profiles do not typically look like a slipper cam profile and I dont think its possible to grind a true roller profile from a slipper cam. You can grind them so they will work, but that does not mean they perform like a true roller cam. So far the people who have done dyno testing have not seen gains from the after market roller cams compared to stock, which is disturbing, this should not be the case.

 

But if there is a stock roller cam that will work, why not use it. And why not use it for "performance" grinds? Are these cams that hard to get a hold of? Are the rockers unique to that app, or are they the same as the ones we are trying to use in the states? More info is needed.

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Seems like they either work or don't on a stock camshaft. You tried and it did not work.

 

You now need to get a hold of someone that can figure out the problem and as suggested on here there are a few.

 

As indiana said you can't run a mechanical shaft with hydraulics.. regardless if the are rollers or not. No oil will get to the lifters.

 

Are the lifters stuck? pumped up?

 

What length valves are you running? You need proper lash on hydraulics,,,, too much and it can rattle, pound out the valve tip. Too little and it can hold the valve open.

 

Be sure the extra lift isn't coil binding your springs, or causing the retainer to beat on the valve seals.

 

 

Roller rockers are Not always a direct bolt on mod.

 

Once you get the oiling figured out and the proper lash maybe it will run ok,, then again maybe you will need to again look for a roller ground camshaft.

 

 

Dad

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I am trying to get my hands on the Magna roller to see if the grind can be made on a stock non-magna core. So far, the person who had one, can't seem to find it.

There are many challenges that the roller set-up produces. All of which need overcome just to properly set one up to run without mechanical problems. i.e. proper lifter preload, valvespring pressure, stem seal clearance, etc... I overcame those issues with my grinds. However, most of my roller grinds are for moderate boost levels and definitely below 18PSI for most engines.

I have one grind that will flow as much boost as you want to throw at it, but the grind specs don't look impressive, so I rarely can convince people to buy it. Everyone wants big lift and durations that require more valvespring than an HD spring can give. You can use an HD spring, but it usually needs shimmed quite a bit to get 105-110 Lbs of seat pressure. A big reason people aren't getting good dyno numbers is the valves are floating. I guarantee it. People run way too much boost too. Anything over 18PSI severely lessons the life of the engine, so I made that my target limit for flow for most of my roller cams on a mid to large sized turbo.

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Ok, i put my slipper rockers back in today.... didn't even wanna bother with the rollers (for now) later on i will do a roller conversion, hopefully by then someone will have a very good roller grind for these engines... until then my car is running fine like it is.... if i can get this high idle problem figured out now!! Me and this car are going rounds... :fighting0061: maybe someday it can be a daily driver :driving: I agree with the magna cam idea... i think i will do some research and try to locate one as well, ppl pls feel free to keep giving out advice about roller rocker installs, and thanks for all the input :hmm3grin2orange:
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Ok, i put my slipper rockers back in today.... didn't even wanna bother with the rollers (for now) later on i will do a roller conversion, hopefully by then someone will have a very good roller grind for these engines... until then my car is running fine like it is.... if i can get this high idle problem figured out now!! Me and this car are going rounds... :fighting0061: maybe someday it can be a daily driver :driving: I agree with the magna cam idea... i think i will do some research and try to locate one as well, ppl pls feel free to keep giving out advice about roller rocker installs, and thanks for all the input :hmm3grin2orange:

 

lol, I think the guy who posted above you there has a few very good roller grinds for this engine. Just depends where you want to go with it. For daily drivable power the roller is the best thing that ever happened to my engine.

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Shelby, where is that roller cam???

 

 

man i try'd but no luck,, only one aplication i know of that has a cam that will fit our heads is the aussie magna , now that presents a problem as mention'd earlier i doubt they can be ground useing a stock sliper cam so that means new stock has to be use'd ( ups the price a bunch )or we have no choice but to go with good use'd aussie cams , and shiping is a pain from aussie and their rockers i have heard are a diff ratio then the 3.0 rockers we have been useing meaning some remachineing may have to be done to the oem magna rockers to use on our head , all this is guess work as i have not seen the aussie cam or the aussie roller rockers personaly

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If anyone has the OEM part number for the magna roller cam, I could try to order one and do the research to see if it will bolt-in, and or what mods are needed to run it.
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