Generation IV Internal Engine - Will someone weigh a stock 2.16 L92 intake valve!!!??

it would be much appreciated.... also do you know the weight of the stock titanium C6Z06 intake valve for comparison???

apparently Manley is making aftermarket valves... they did for Livernois?

108.5 Grams on a slightly used stock steel one. That's at least something to compare to.

You ever weight a AFR 225 valve?

Bret

You ever weight a AFR 225 valve?

Bret

for those in the know..... do you mind posting the weight of an aftermarket 2.08 valve...... hollow stem is preferred.

also do you know the weight of the stock titanium C6Z06 intake valve for comparison???




Intake was 76g. and exhaust was 72g.

Intake was 76g. and exhaust was 72g.


so if the stock LS7 valves weight in around 74grams and the L92 is around 108grams...... wont we see floating issues?

The stock L92 valve is still lighter than a 2.1" solid stem (109g) 8mm LS1/LS2 intake valve. A 8mm solid stem 2.08" valve is 107g. A 11/32" solid stem 2.02" stock length valve for your older SBC's is 111g. These number's should help put perspective on this discussion. For the size of the stock L92 heads they seem fairly light to me. With a good after market valve spring, valve float should not be a problem.

so if the stock LS7 valves weight in around 74grams and the L92 is around 108grams...... wont we see floating issues?


They are 76 g., not 74, my REV L-92's were 103g., with a quality spring, you should not have any valve control issue's. I have a set of AFR 205 valves, I'll pull the scale out and see how much they are for a comparision. I ran those heads to 7k with the 8019 springs and LSK lobes with no issues.

They are 76 g., not 74, my REV L-92's were 103g., with a quality spring, you should not have any valve control issue's. I have a set of AFR 205 valves, I'll pull the scale out and see how much they are for a comparision. I ran those heads to 7k with the 8019 springs and LSK lobes with no issues.


i was saying average of the intake and exhaust.

Weigh those AFR's for me.... and if anyone else has an LSx valve go ahead and weigh it as well..... just for comparisons sake. I wanna put this to bed.

Original LS1 2" intake 100.3G, exhaust 85.8G. Stock L92 intake 108.5G, exhaust 89.3G.

Ron

Intake was 76g. and exhaust was 72g.

what I was looking for is an aftermarket titanium valve for the l92 with stock size.... I wonder .... it the LS7 valve longer/shorter or same length?..... can it be cut down to a 2.16?

The titanium LS7 valve obviously is bigger and yes, it could be cut down, but the length of it is the problem.

My REV L-92's were 103 g., with a quality spring, you should not have any valve control issue's.
But how many rpms are you spinning with that? A lighter valve will allow you to spin more rpms. I would like to spin more than 7k if possible with a hydraulic setup.

Ti your looking easily at 83g for a L92 valve, maybe even lighter if you play with the underside of the valve, tulip and the margin.

Bret

Do you think roughly 20 (103 - 83) grams per intake valve (160 grams total) is worth $800+ compared to $130-$160 for a stainless steel set?

We kill for 3 grams, much less 20.

I measured a stock Ti LS7 and it tipped the scale at 76 grams with the lash pad.

Stock L92 intake valve - 108-109 grams
Stock LS7 intake valve - 76 grams
Aftermarket L92 intake valve - 103-104 grams
Aftermarket titanium intake valve - 83 grams (estimate)

So 20 grams is a lot? What all benefits do you obtain with 160 grams total (8 valves - 20 grams saving each)?

SStrokerAce, how are you estimating 83 grams for a titanium L92 intake valve?

The Ti Valves I am doing for the L92 are about 75 grams so that's basically 30+ grams lighter.

With the right cam lobes and springs the stock L92 valves will still probably go 7000 rpm easy but losing 30G off of them makes a lot more possible.

The Ti Valves I am doing for the L92 are about 75 grams so that's basically 30+ grams lighter.

With the right cam lobes and springs the stock L92 valves will still probably go 7000 rpm easy but losing 30G off of them makes a lot more possible.


Erik.... I sent a stock intake valve to you, it will arrive by tuesday, if ya need the other 7 let me know.

I dont plan to spin mine to 7k.... but 6700rpm would be nice, and 7k max for any stock tachometer misreadings.

I just cant see paying over 800 bones for intake valves right now. If an aftermarket set for under 250 was available that would suffice.... but not 800 bones for what I am wanting to accomplish.

Are the LS7 ex valves ti? I know they are hollow.
Also, can some one confirm that they are not the same hight as the L92 ex valve.

The LS7 exhaust valves are stainless and sodium filled and they are a lot longer than L92 valves (by about .300"). The LS7 valves could be fitted into a L92 head but the spring installed height would be quite tall. Also the rocker stands will need to be shimmed to correct rocker geometry.

Richard :)

Weight of intake valve illustrates RPM shifted upward quite a biit and no real reason to go to titanium on exhaust valve. ITs inertia which will be rpm and weight dependant which cause the float.

Its not just the valve thats the problem but everything on the valvetrain.

Is why some of us where scratching heads on where to remove weight at, and rev kit came up.

I don't think theh rev kit was ever "maxed out" yett, because doing so basically takes the lifter weight out of the equation. Isky cams quoted that even if they moderately improve RPM on even a solid roller app, that they prevent lifter on solid app from leaving the lobe, greatly improving the lifter bearing life.

Pro stock bike is hitting 14,000 RPM with pushrods, is there something that can be borrowed from over there?

DOHC is tite, but the thing that really gives the F1 DOHC RPM potential is the pneumatic "valvespring". Heard this was adapted by some to pushrods in the past but it was outlawed, as usual some tangents to explore.

Big-DEN, you have something there.... not going to say what but good thinking.

Big-DEN, you have something there.... not going to say what but good thinking.
Why must everything be a secret with you?

Has anyone even used a Rev kit around here latley? Seems like it could cure some of the "floating issues. I believe it would be a good investment for you guys wanting to go 7k+ with the heavier valves.

Why must everything be a secret with you?

Because I don't do care to share it for free.... most people who can actually do this stuff well don't care to either.

The big deal here is getting more RPM for less money, that's a hard equation to work out, always has been. Mostly it just takes the right combination of parts working together and take trade offs to get what you are looking for. The biggest problem is people keep doing the same things over and over again and getting the same dam results. You can't use cheap springs, aggressive lobes and flexable valvetrains to get something to make power and live with more and more RPM, it don't work that way.

Bret

Bret,

How many rpm do you believe one would have to back off going from say XER to LSK lobes, keeping everything else constant? Do you think that the 5/16th aftermarket pushrods have anything to do with the "flexible valvetrains"? Do you consider Patriot Golds to be cheap springs?

And since you compete in the engine masters challenge, maybe we'll let you get away with keeping a few secrets...

Compared to what lobes really..... It's a full design. Depends on your springs (all of them pushrods and rockers included), mass (all of them, spring, valve, retainer, lock) and the lobes. There can be little changes to the lobes and you can see 200rpm and it LOOKS like the same cam card. Hell how you setup the springs is part of that. Good 5/16 pushrods in a LS motor are even being taxed with the rocker ratio.

The LSK lobes should get you MORE RPM not less, due to the lift but instability/bounce might come at a earlier RPM with the wrong combination. I know PAC is doing some spintron stuff to come up with a spring that works with the LSK lobes well. Last I heard nothing is good enough yet. Again I think it's a combination of things in the end. People just don't pay attention to details (not PAC, not to inferr that they are doing the right thing) but I think as a group there is not enough scientic tests done to get to the problem.

I'd really like to know more about those Patriot springs. I just can't believe you can put Ti barstock with Kobe quality pure spring wire and come up with a cheap spring and retainer setup. (You can't) To take money out you have to be doing something less, or buying something really cheaply, either machine time, spring wire, ti quality. I realize there is a advantage to large quantities but I guess I missed that Econ class where you lock your money into materials and then don't get a return on that money when you are waiting for the products to sell? I don't know the economies or specifics of those parts so I can't say anything on that.

I do know that you just can't get something for nothing unless someone is getting passed a tube of KY when they get paid.

Bret

Why must everything be a secret with you?

All babblers do that. :jest:

And who has the 11,000 posts? Hmmmm

And who has the 11,000 posts? Hmmmm moron.
LMAO some of the people just don't get it Bret.

The exhaust valves are hollow the intakes are titanium with lash caps, I am quite sure they are longer and if my memory serves me........ + .100 sounds correct.

What about 2002 LS6 exhuast valves?

Are they 1.55", or 1.59" like the L92?
Supposedly they only weigh 63 grams!

From http://www.idavette.net/hib/02ls6/page2.htm
"The ’01 intake weighed 99 grams but the ’02 weighs only 76. The ’01 exhaust weighed 86 grams but the ’02 exhaust weighs 63 grams."

I'd have to weight one at the shop, but yeah the stock LS6 valves are about as light as you are going to get. I have a set of Ti replacements for them in the shop and they save like 2-5g's per valve!

Bret

To give an idea of how things have changed:

Big Block Stainless OEM Valves: 2.19 intake - 151.2 g., 2.25 intake - 162.4 g. and 1.72 exhaust - 121.8 g. :cry:

I didn't have a 2.3 intake or a 1.88 available, but I'm sure they would be grim indeed! :eek2:

Be glad that you didn't have to deal with these!

And who has the 11,000 posts? Hmmmm



point goes to the stroker