The quickest/fastest GTR’s in the world all run shims in their RB cylinder heads, and they don’t spit them. If you’re spitting shims, there are other issues at play.
Interesting. On other Nissan engines, when they wanted to eliminate shims, they would use parts from Nissans that already had different cam buckets. Often it would be a VQ35DE.
I can't think of another Nissan head that uses the VQ bucket besides the VR. To get one to fit a TB is a ton of work, and the KA is a totally different bucket.
@@headgames I wouldn't say totally different bucket. KA is 34mm across by 26mm tall. VQ is 34mm across by 21mm tall. I can confirm this works as I have done it and is a good no-shim solution for high revving KA's.
Why not address the valve float issue instead of just addressing the result? Seems if you change over to shimless setup without addressing float problem then your not worrying about spitting a shim but still losing power from valve float and possibly tagging a valve. Have you looked into why it’s floating the valves to begin with? Usually it’s a lack of spring pressure or the cam profile isn’t right. I don’t build these exact engines but I do build suzuki hayabusa and gsxr1000 engines and they both use shim under bucket setups just like what you showed where the retainer has the counterbore for the shim. I’ve never spit a shim and we turn 11.5k rpm on the busa and closer to 13k on the 1000. I’ve really never heard of people spitting shims on busas and only rarely on the gsxr 1000 and it uses really small od shims and really thin too. All long as the seat pressure is set right and you use a quality valve spring with the proper pressure then it ok. Is it more of a problem with people that build their own engines and think that as long as everything spins without anything hitting then they good to go???? Or is it across the board problem from even qualified builders seeing this shim spitting problem? Anyway, interesting stuff, like your videos I just found the channel and I’m checking out more videos from your “back catalog” so to say. As I commented in another, do you do any bike heads?
To counter this reply, bike engines are most often times not turbo charged/under high boost pressures which is a high, if not the highest, contributing factor to valve float. Even more so prone to float valves if the valves are oversized since its just more surface area for the valve head forced by the boost pressure to float off the cam.
@@jameshudson8357 actually the bikes engines I build are turbocharged often or heavy nitrous. I build dragbikes for the no wheelie bar classes commonly referred to grudge bikes or as pro street or what was originally streetbike shootout class. We put 40-50lbs of boost on methanol just like the real fast car guys do. Pretty much identical design of the valvetrain/head for the most part other than just being smaller dimensions/scaled for and they rarely spit shims. Actually the only times I’ve personally had it happen is on Gsxr1000 where the bucket bores are so small they only have enough room for single valve springs not doubles like on most big bikes and so the springs available aren’t always the greatest.
Why not just go with stronger springs? I see this being an issue with once that valves wear you no longer can adjust and measuring the gap to replace the shims like prior... So now you gotta get a bunch of buckets? How does that work? Iam just curious.
That is what we did, much stronger spring and got rid of the puck. We don't need a bunch of different buckets, we machine the tip of the valve to achieve the lash.
No come backs!! Y'all doin the Lord's work
haha well, not for this issue at least.
Too humble! Shitting out the shims is THE issue on them heads
Always gotta be one step ahead... btw thats a nice looking RB Head ya got there
Theres a few oe buckets that adapt straight over making the Kelford buckets a best option but not only shimless
Great information as always.
Thanks for the great information
The quickest/fastest GTR’s in the world all run shims in their RB cylinder heads, and they don’t spit them. If you’re spitting shims, there are other issues at play.
@@flamintasty what valve spring are they using?
I gotta take the time and contact you guys for my rb26 🍻👍🏼
Interesting. On other Nissan engines, when they wanted to eliminate shims, they would use parts from Nissans that already had different cam buckets. Often it would be a VQ35DE.
I can't think of another Nissan head that uses the VQ bucket besides the VR. To get one to fit a TB is a ton of work, and the KA is a totally different bucket.
@@headgames Okay, that would explain why the time I head of it, it was someone race prepping a KA24DE
@@headgames I wouldn't say totally different bucket. KA is 34mm across by 26mm tall. VQ is 34mm across by 21mm tall. I can confirm this works as I have done it and is a good no-shim solution for high revving KA's.
with a standard length valve? What size bucket did you do? Because we tried that and it wouldn't work without a lot of work.
@@dreednlb
@@headgames Third try.... youtube keeps deleting my comment...
What about for the 25neo?
Magnetize the shim or bucket so shim doesn’t spit?
or just get rid of it
Why not address the valve float issue instead of just addressing the result? Seems if you change over to shimless setup without addressing float problem then your not worrying about spitting a shim but still losing power from valve float and possibly tagging a valve.
Have you looked into why it’s floating the valves to begin with? Usually it’s a lack of spring pressure or the cam profile isn’t right. I don’t build these exact engines but I do build suzuki hayabusa and gsxr1000 engines and they both use shim under bucket setups just like what you showed where the retainer has the counterbore for the shim. I’ve never spit a shim and we turn 11.5k rpm on the busa and closer to 13k on the 1000. I’ve really never heard of people spitting shims on busas and only rarely on the gsxr 1000 and it uses really small od shims and really thin too. All long as the seat pressure is set right and you use a quality valve spring with the proper pressure then it ok. Is it more of a problem with people that build their own engines and think that as long as everything spins without anything hitting then they good to go???? Or is it across the board problem from even qualified builders seeing this shim spitting problem?
Anyway, interesting stuff, like your videos I just found the channel and I’m checking out more videos from your “back catalog” so to say. As I commented in another, do you do any bike heads?
Well, we are solving both issues with this kit. It doesn't float and it doesn't have anything to spit out when it does.
To counter this reply, bike engines are most often times not turbo charged/under high boost pressures which is a high, if not the highest, contributing factor to valve float. Even more so prone to float valves if the valves are oversized since its just more surface area for the valve head forced by the boost pressure to float off the cam.
@@jameshudson8357 actually the bikes engines I build are turbocharged often or heavy nitrous. I build dragbikes for the no wheelie bar classes commonly referred to grudge bikes or as pro street or what was originally streetbike shootout class. We put 40-50lbs of boost on methanol just like the real fast car guys do. Pretty much identical design of the valvetrain/head for the most part other than just being smaller dimensions/scaled for and they rarely spit shims. Actually the only times I’ve personally had it happen is on Gsxr1000 where the bucket bores are so small they only have enough room for single valve springs not doubles like on most big bikes and so the springs available aren’t always the greatest.
🇦🇬
⭐️⭐️⭐️⭐️⭐️.
🙇🏾♂️
Why not just go with stronger springs? I see this being an issue with once that valves wear you no longer can adjust and measuring the gap to replace the shims like prior... So now you gotta get a bunch of buckets? How does that work? Iam just curious.
That is what we did, much stronger spring and got rid of the puck. We don't need a bunch of different buckets, we machine the tip of the valve to achieve the lash.
@@headgames Ohhh okay I seee. Very interesting. I assume it obviously works since you have had such good success with them. Great stuff!