SPACK 68 Posted September 4, 2018 Guys is it possible to fit ROLLER ROCKERS TO AN XF EFI ENGINE/HEAD....if so is there a NOTICEABLE DIFFERENCE, NOT ONLY IN PERFORMANCE, BUT ECONOMY. Cheers Share this post Link to post Share on other sites
gerg 10,871 Posted September 4, 2018 Guys is it possible to fit ROLLER ROCKERS TO AN XF EFI ENGINE/HEAD....if so is there a NOTICEABLE DIFFERENCE, NOT ONLY IN PERFORMANCE, BUT ECONOMY. CheersPossible: Yes (Cleveland style bolt-on rockers)Performance: noEconomy: noStock rockers are fine for stock or mild engines, just use a good quality zinc oil or a moly additive to prevent wear in the pivot over a long period. Roller rockers are mechanical insurance for a modified valvetrain ie: bigger cam, stiffer valve springs, higher rpm. With the greater forces involved with all of these aspects, the roller pivot and tip reduce friction and wear. The oil stays cleaner due to reduced shearing/breakdown.If you ever do go down that path, don't skimp on the quality. Lots of tiny hardened needle rollers floating around your engine is what we call a "Chernobyl" in the trade.Sent from my CPH1607 using Tapatalk 3 matt_lamb_160, Mixalis and SPACK reacted to this Share this post Link to post Share on other sites
bear351c 10,260 Posted September 4, 2018 Agreed. +1. Clevo adjustables like YT6015 aren't cheap. (around $900, bolt on, 5/16" stud). Scorpion do a new set #3224,but haven't found a price for them yet. Non adjustables are around $600. and you'll have 2 spares. 1 SPACK reacted to this Share this post Link to post Share on other sites
slydog 7,873 Posted September 4, 2018 If you buy the scorpian set for a v6 thunderbird there cheaper and you get the correct number. Buying a V8 set leaves you 4 left over which is handy at times. 1 SPACK reacted to this Share this post Link to post Share on other sites
ando76 4,354 Posted September 4, 2018 16 hours ago, bear351c said: Agreed. +1. Clevo adjustables like YT6015 aren't cheap. (around $900, bolt on, 5/16" stud). Scorpion do a new set #3224,but haven't found a price for them yet. Non adjustables are around $600. and you'll have 2 spares. Be careful buying Yella Terra clevo for xflow if your buying a new set. YT have changed the design of their rockers. God only knows why they would change a design that's worked faultlessly for so many years, especially on a Clevo that went out of production 40 odd years ago, but they have. The new clevo design uses a 17mm pedestal whereas the old design uses a 14mm - same as crossflow. Some sets of the new design went out with a 14mm pedestal before they realised the new design has geometry issues on clevo if you try and use a 14mm pedestal - ask me how I know. Arghhh. So long story short - if your buying new for crossflow - specify xflow. But as others have said there is no advantage in a stocker and fitting them under the rocker cover with stock efi is a right pain. 2 bear351c and gerg reacted to this Share this post Link to post Share on other sites
SPACK 68 Posted September 5, 2018 On 9/5/2018 at 4:02 AM, gerg said: Possible: Yes (Cleveland style bolt-on rockers) Performance: no Economy: no Stock rockers are fine for stock or mild engines, just use a good quality zinc oil or a moly additive to prevent wear in the pivot over a long period. Roller rockers are mechanical insurance for a modified valvetrain ie: bigger cam, stiffer valve springs, higher rpm. With the greater forces involved with all of these aspects, the roller pivot and tip reduce friction and wear. The oil stays cleaner due to reduced shearing/breakdown. If you ever do go down that path, don't skimp on the quality. Lots of tiny hardened needle rollers floating around your engine is what we call a "Chernobyl" in the trade. Sent from my CPH1607 using Tapatalk Got the CAM, and the DOUBLE VALVE SPRINGS, so it shouldnt be a problem.. Share this post Link to post Share on other sites
Lord_fahrquhar 2,580 Posted September 6, 2018 Okay flow rockers are basically clevo type but in two stud sizes. 5/16 pedestal mount - no machining 7/16 stud mount - needs machining The 5/16 this run the risk of pulling out at high rpm - but this is dependent on your cam size and valve spring pressure. This is something ando gets very passionate about. I’m surprised the mention of double springs hasn’t woken him up. the 7/16ths are more common and easy to get but need the pedestal machines to take the stud mount. They tend to be more stable but n high rpm scenarios, and then if you’re really serious in running a big cam you need pushrods and guide plates. But this is a serious engine something that sacrifices some crossy strengths ( low down torque) and drive ability for those moments when you can hold a throttle fat and go waaa waaa waaa. i have a set of the 5/16 adjustables in my xf. It’s efi, they do not fit under the efi cover without an aussiespeed spacer. It’s also not standard efi - eb inlet el ecu with quarter horse. i could have gone v8 had less hassles but I kinda like how friendly the crossy is. It’s not a fast combo but it’s a great streeter with a Bit of attitude which I’ve learnt a lot from. Other guys like rob and ando will have their own bit to add to this but hopefully this helps in the interim Dave 3 gerg, Mixalis and SPACK reacted to this Share this post Link to post Share on other sites
SPACK 68 Posted September 6, 2018 12 hours ago, Lord_fahrquhar said: Okay flow rockers are basically clevo type but in two stud sizes. 5/16 pedestal mount - no machining 7/16 stud mount - needs machining The 5/16 this run the risk of pulling out at high rpm - but this is dependent on your cam size and valve spring pressure. This is something ando gets very passionate about. I’m surprised the mention of double springs hasn’t woken him up. the 7/16ths are more common and easy to get but need the pedestal machines to take the stud mount. They tend to be more stable but n high rpm scenarios, and then if you’re really serious in running a big cam you need pushrods and guide plates. But this is a serious engine something that sacrifices some crossy strengths ( low down torque) and drive ability for those moments when you can hold a throttle fat and go waaa waaa waaa. i have a set of the 5/16 adjustables in my xf. It’s efi, they do not fit under the efi cover without an aussiespeed spacer. It’s also not standard efi - eb inlet el ecu with quarter horse. i could have gone v8 had less hassles but I kinda like how friendly the crossy is. It’s not a fast combo but it’s a great streeter with a Bit of attitude which I’ve learnt a lot from. Other guys like rob and ando will have their own bit to add to this but hopefully this helps in the interim Dave Thanks for the info..do you find it HELPS your engine in any way? Share this post Link to post Share on other sites
deankxf 20,231 Posted September 6, 2018 i think if you had EFI and needed to space the rocker cover, then the efi gear won't fit back on(the standard bananas type) so beware of that. 1 Valvebouncer reacted to this Share this post Link to post Share on other sites
Slow250XC 1,512 Posted September 7, 2018 These are what i used with mine. https://www.summitracing.com/parts/crn-52655-2 https://www.summitracing.com/parts/lun-15380-1 4 Valvebouncer, SPACK, Mixalis and 1 other reacted to this Share this post Link to post Share on other sites
Lord_fahrquhar 2,580 Posted September 7, 2018 On 06/09/2018 at 11:29 PM, deankdx said: i think if you had EFI and needed to space the rocker cover, then the efi gear won't fit back on(the standard bananas type) so beware of that. This is true too 1 SPACK reacted to this Share this post Link to post Share on other sites
Mixalis 266 Posted September 8, 2018 On 07/09/2018 at 6:37 PM, Slow250XC said: These are what i used with mine. https://www.summitracing.com/parts/crn-52655-2 https://www.summitracing.com/parts/lun-15380-1 Thats looks like a cool way around it Share this post Link to post Share on other sites
ando76 4,354 Posted September 11, 2018 On 07/09/2018 at 6:30 AM, Lord_fahrquhar said: Okay flow rockers are basically clevo type but in two stud sizes. 5/16 pedestal mount - no machining 7/16 stud mount - needs machining The 5/16 this run the risk of pulling out at high rpm - but this is dependent on your cam size and valve spring pressure. This is something ando gets very passionate about. I’m surprised the mention of double springs hasn’t woken him up. the 7/16ths are more common and easy to get but need the pedestal machines to take the stud mount. They tend to be more stable but n high rpm scenarios, and then if you’re really serious in running a big cam you need pushrods and guide plates. But this is a serious engine something that sacrifices some crossy strengths ( low down torque) and drive ability for those moments when you can hold a throttle fat and go waaa waaa waaa. i have a set of the 5/16 adjustables in my xf. It’s efi, they do not fit under the efi cover without an aussiespeed spacer. It’s also not standard efi - eb inlet el ecu with quarter horse. i could have gone v8 had less hassles but I kinda like how friendly the crossy is. It’s not a fast combo but it’s a great streeter with a Bit of attitude which I’ve learnt a lot from. Other guys like rob and ando will have their own bit to add to this but hopefully this helps in the interim Dave Very good information in here. Yes I do get passionate about a few things and spring pressures is one of them cause it's an area a lot of people get wrong. At best it causes a waste of mechanical effort, and at worst it breaks stuff that should never break. But in recent times I've learnt to just sit back and watch. One has to wonder why this efi engine has 'double springs' in the first place as the stock ecu is not capable of supporting big lift cams. I'd be more concerned with that. Just to say it has double springs isn't enough. Seat and nose pressure are more important as is who manufactured the springs. I really see no reason to go to roller rockers in this application, especially after watching several factory pressed steel rocker cars run at 6banga Nats. Sure they were turbo cars that were making decent snot through boost so they didn't need massive lift and overlap Cams, but they were getting pinned run after run. I'm returning to my slumber now Dave 1 bear351c reacted to this Share this post Link to post Share on other sites
bear351c 10,260 Posted September 11, 2018 13 hours ago, ando76 said: One has to wonder why this efi engine has 'double springs' in the first place as the stock ecu is not capable of supporting big lift cams. I'd be more concerned with that. Just to say it has double springs isn't enough. Seat and nose pressure are more important as is who manufactured the springs. I really see no reason to go to roller rockers in this application, yep. Share this post Link to post Share on other sites