Teaser pics of new head
10-14-2005, 10:55 AM
#11
solid lifters vs hydraulic lifters
tisk tisk...
solid lifters remove the hydraulic elements that are used to "self adjust" the contact between the CAMs and the valve lifter.
Basically solid lifters are handy when you want to go to higher RPMS and dont want to worry about valve float (aka the valves opening or staying open longer than desired)
here is a good site to do some reading on<ul><li><a href="http://www.lindseyracing.com/Merchant2/merchant.mvc?Screen=CTGY&Store_Code=LR&Cat egory_Code=944VALVESPRINGS">porsched valve springs</a></li></ul>
solid lifters remove the hydraulic elements that are used to "self adjust" the contact between the CAMs and the valve lifter.
Basically solid lifters are handy when you want to go to higher RPMS and dont want to worry about valve float (aka the valves opening or staying open longer than desired)
here is a good site to do some reading on<ul><li><a href="http://www.lindseyracing.com/Merchant2/merchant.mvc?Screen=CTGY&Store_Code=LR&Cat egory_Code=944VALVESPRINGS">porsched valve springs</a></li></ul>
10-14-2005, 11:45 AM
#12
Maybe cuz you're thinking "lift" means a direction away from earth :D
Since these are upside down in movement with respect to the traditional pushrod engine they originated from, they probably should be called pushers. But maybe if you visualize them as the thingamajigs to lift the valve from it's seat, then it might be easier to visualize them as lifters 
my 2 cents anyway.
my 2 cents anyway.
10-14-2005, 11:55 AM
#13
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Now why would any of us need to go to 9k rpms if the peak is at 7k and power drops off at 8k?
I plan on taking my stock valvetrain to 8200 only because it then puts me in the meat of my power band on the next gear.
10-14-2005, 12:55 PM
#15
I think it would depend on the car/setup
much like with your monster of a turbo...7krpms isnt going to cut it. Especially as you mentioned for staying in the power band on the next shift. What RPM does your turbo start to run out of breath? I can imagine it can hold power to 8k+.
In addition, I've heard examples of the audi hydraulic lifters starting to float around 7500 rpms, thus robbing some of that top end.
I'm also guessing if we plotted out a power curve it would at least hold flat at those ranges on your car
In addition, I've heard examples of the audi hydraulic lifters starting to float around 7500 rpms, thus robbing some of that top end.
I'm also guessing if we plotted out a power curve it would at least hold flat at those ranges on your car
10-14-2005, 10:32 PM
#18
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Here is a graph from a vag log that I did a little while back.
<img src="http://home.comcast.net/~audi2ptzero/maf-dyno.JPG">
I also just had the car dyno'd up in Norcal on a mustang dyno that tends to read 10-15% lower at the wheels then a Dynojet IME. It put down 390 whp and I should have a copy of the dyno plot on monday. This was base run of 18psi before they install the stand alone and do tuning with it.
Most of the people that I have talked to that had valve float on the 20v all missed a shift and had the rpms go well above 8500 rpms. I haven't had any problems taking the stock valvetrain to 7800 rpms so far and will push it a bit futher with the stand alone.
I also talked to the owner of TJM about the solid lifters he had on his car and he said it was a waste of time since his power band cut off within the stock valve train limits so he didn't really ever need to run it to the limits of the solid lifters. Lucas also runs solid lifter and a 2 liter BT setup, I will have to ask him if his power band reaches into the 8500 rpm range.
I also just had the car dyno'd up in Norcal on a mustang dyno that tends to read 10-15% lower at the wheels then a Dynojet IME. It put down 390 whp and I should have a copy of the dyno plot on monday. This was base run of 18psi before they install the stand alone and do tuning with it.
Most of the people that I have talked to that had valve float on the 20v all missed a shift and had the rpms go well above 8500 rpms. I haven't had any problems taking the stock valvetrain to 7800 rpms so far and will push it a bit futher with the stand alone.
I also talked to the owner of TJM about the solid lifters he had on his car and he said it was a waste of time since his power band cut off within the stock valve train limits so he didn't really ever need to run it to the limits of the solid lifters. Lucas also runs solid lifter and a 2 liter BT setup, I will have to ask him if his power band reaches into the 8500 rpm range.
10-15-2005, 11:11 AM
#20
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You will make more power at higher rpms if cams head and turbo caqn supply more air
What I think you are saying is that your engine as currently configured breaths best at 7000. My power is still rising quickly at a 7000rpm redline, so block, head, turbo combinations do make a diff. as far as where peak power is made, my current turbo and perhaps lifters will run out shortly after that, but if they were larger the curve would continue in my exp.. Altho I think the 9000rpm mentioned before is a bit out of range for almost any level. It would take a big AR Gt35 or better to do much at that level and as always power would be down @ lower rpms
Just my .02$
Just my .02$