R&D thread for shim-under-bucket conversion!
#21
2 Props,3 Dildos,& 1 Cat
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oh herro: $30 lash caps. Are these the ones you got from the weight lifter company? haha
http://cgi.ebay.com/ebaymotors/NEW-B...2em118Q2el1247
http://cgi.ebay.com/ebaymotors/NEW-B...2em118Q2el1247
#22
So, longer duration/lift allows more air through the head? I thought the limitation of the head was the actual layout of the air passages (small) and not the size/volume of the valves.
In the end, how much more RPM are we talking about here? The number for the stock valvetrain seems to be 7200 as an upper limit. To be worth anything, I'd think you'd want to see a 500-800rpm improvement. So, would converting to shim/bucket let you get up to the 8000rpm range... 8500?
I hesitate to think what the next limitation is. Turbo flow? Pump gears? Bottom end?
This mod isn't for me, but I'm still trying to figure out what the end-result in performance will be. Will it make more power? Will it rev quicker? If so, then how much... and where will you see the gains... and will the wear-and-tear on other components be worth it?
In the end, how much more RPM are we talking about here? The number for the stock valvetrain seems to be 7200 as an upper limit. To be worth anything, I'd think you'd want to see a 500-800rpm improvement. So, would converting to shim/bucket let you get up to the 8000rpm range... 8500?
I hesitate to think what the next limitation is. Turbo flow? Pump gears? Bottom end?
This mod isn't for me, but I'm still trying to figure out what the end-result in performance will be. Will it make more power? Will it rev quicker? If so, then how much... and where will you see the gains... and will the wear-and-tear on other components be worth it?
#23
2 Props,3 Dildos,& 1 Cat
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the stress on the bottom end goes up exponentially with RPM so yes, that may very well be the limitation. I think with a full top to bottom motor build, running 8k isn't out of the question. Hell, I'll try it.
Lets see... all flow related items that need more flow with higher RPM become limiting factors: injectors, turbo, pumps can cavitate, harmonic damper, etc.
but the benefits are (if you keep your torque up) linear increase in hp as revs increase. Think S2000. Look at the power go up above 7000 rpm... yet torque is constant.
#26
I don't know the specs on the springs we used with our cams but they were noticeably less stiff just by squeezing. Ideally you want less spring rate for a lighter valve train since you're moving less mass. I'm paraphrasing the engine builder, but the spring rate needs to be stiff enough for a good return on the valve (quick action) with minimal force against the lobe at compression. That said, we weren't revving past 7500. Our cams were geared more for torque and not high rpm power. So rev limit would also play into spring rate to avoid float. My guess is that's the point behind upgrading the springs on the stock valve train - to keep those giant shims from shooting out.
#34
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SO I found a couple things:
1. Manley makes 6mm lash caps that run for 30-45 for a whole set depending on where you get them (flatlander, summit, jegs).
2. the FM valve springs are the exact same rates listed on the supertech website. belfab has the set for roughly the same price.
3. Actually with a little looking around, Import Performance Parts/Flatlander has the valves and springs significantly cheaper than other places.
hmm.
1. Manley makes 6mm lash caps that run for 30-45 for a whole set depending on where you get them (flatlander, summit, jegs).
2. the FM valve springs are the exact same rates listed on the supertech website. belfab has the set for roughly the same price.
3. Actually with a little looking around, Import Performance Parts/Flatlander has the valves and springs significantly cheaper than other places.
hmm.
#35
oh herro: $30 lash caps. Are these the ones you got from the weight lifter company? haha
http://cgi.ebay.com/ebaymotors/NEW-B...2em118Q2el1247
http://cgi.ebay.com/ebaymotors/NEW-B...2em118Q2el1247
#38
The retainers are made specifically for the springs. The super tech springs require their springs seats and retainers for out cars. My super tech springs were actually shorter than the stock springs. The winding wasn't as tight though, so they could still support more lift.
I would definitely get the entire valve train in a kit Matt. Those are the shims I am using though. I probably have 40hrs invested in grinding them myself with the knife sharpener though. I couldn't find a place locally that would grind them for me. Most places thought I was crazy to even ask.
I would definitely get the entire valve train in a kit Matt. Those are the shims I am using though. I probably have 40hrs invested in grinding them myself with the knife sharpener though. I couldn't find a place locally that would grind them for me. Most places thought I was crazy to even ask.