TU and F4 Camshaft Follow-on Discussion

[moparzrule]

The specs are already posted as far as what we are going to get from the cam grinder. So until someone actually takes the time to degree/ instal one, we won't have anything more.

Can you enlighten us as to where these are posted? I can't seem to find any info on the F4 contained in this thread (that isn't posted on FWD's site already anyway). I might be blind, but I don't see any....and I don't think I'm the only one.

[Shadow]

Okay here is some elusive specs on the F4 that I asked for and received early this past summer. Please note I did not degree this camshaft in, but have degreed many others in. FWD lists intake centerline at 116° ATDC along with LSA at 116°. This camshaft was installed at 109° ATDC. So that means it is installed 7° advanced from what FWD catalog lists. 6 degrees advanced from where Rob (Shadow) lists his F4 is installed at. I corrected exhaust duration 1 degree based on open and closed #'s. I also listed overlap which wasn't listed, based on #'s provided. I felt this is an important spec. to list. The rest of the numbers came straight from vendor. Hope this helps.
Todd



Intake: Exhaust:

- Duration @ .050 213 204

- Duration Advertised 282 276

- Valve Lift .470 .467

- Open @ .050 4 ATDC 45 BBDC

- Close @ .050 37 ABDC 21 BTDC

- Overlap @ .050 negative 25°

- LSA 116

- Centerline 109* 123
*advanced 7° based on FWD catalog.

Sure Bro, post #165 by Todd, but Remember, the duration specs are taken off the Lobe, Not the valve, and That is what has confused Most

[bakes]

He is, what made you think otherwise

post333 There is (probably more than one) reason Warren went away from a hydraulic roller camshaft.
Todd

[Shadow]

post333 There is (probably more than one) reason Warren went away from a hydraulic roller camshaft.
Todd

Sure, the reason to get rid of the Hydraulics would be twofold; the .020+ that you're Losing vs solid lifters And the Fact that you Can run a Much more Aggressive cam profile with solid lash adjusters as you can with hydraulic.

[4 l-bodies]

As requested, here is a couple pics on the MP adjustable lash adjuster used for degreeing in cams. Asa, you should be able to make one up easily with your fab skills. Thread is 7/16-20. OD of adjuster is .0015 smaller than OE lash adjuster so it can be easy removed. I'll bet you could also sell some, as I've seen plenty of people looking for them over the years. Last pic shows lighter springs, dimples I place in retainer to help keep indicator from walking around, and how indicator is on same axis and is perpendicular to camshaft. BTW this is slider camshaft and follower.
Todd

[acannell]

As requested, here is a couple pics on the MP adjustable lash adjuster used for degreeing in cams. Asa, you should be able to make one up easily with your fab skills. Thread is 7/16-20. OD of adjuster is .0015 smaller than OE lash adjuster so it can be easy removed. I'll bet you could also sell some, as I've seen plenty of people looking for them over the years. Last pic shows lighter springs, dimples I place in retainer to help keep indicator from walking around, and how indicator is on same axis and is perpendicular to camshaft. BTW this is slider camshaft and follower.
Todd

Those look great. Did you make those? You just gave me something to make on my old worn out lathe finally!!

[bakes]

http://mantonpushrods.com/products/adjusting-screws/

[acannell]

http://mantonpushrods.com/products/adjusting-screws/

do TU or FWDP sell them? that seems like a perfect tool for them to stock

[moparzrule]

Sure Bro, post #165 by Todd, but Remember, the duration specs are taken off the Lobe, Not the valve, and That is what has confused Most

Oh I remember reading that post now, thanks for the reminder. But, now I recall why I didn't remember them....because I did not take them seriously. I have no idea how those numbers are anywhere close to reality. They make no sense. The specs I posted of the R5 are also at the lobe, not the valve. At .050 lobe lift it has 243/235 duration. If those numbers he posted are accurate, the F4 has 30+ degrees less duration than the R5 at .050'' lift and I seriously seriously doubt that.

[bakes]

nope they dont to my knowledge . i Love to run a mechanical again MP at one time long ago had a turbo mechanical slider cam with those lifter adjuster's that's in Todd's pics

[acannell]

riddle me this:

So when comparing cam specs..is it true that all the following can be known regardless of whether the specs are at the lobe or at the valve?

comparisons of duration between cams
centerline
comparisons of overlap between cams if the same point is used for start and end, even if its lobe
LSA
relative valve lift (if cam A has a peak lobe lift of 0.4" and cam B has a peak lobe lift of 0.5", then cam B has 0.1" more actual valve lift than cam A, even though the specs are at the lobe. In this case the actual valve lift cannot be determined without knowing the follower multiplication, but the difference can be determined as described. )

[Shadow]

Oh I remember reading that post now, thanks for the reminder. But, now I recall why I didn't remember them....because I did not take them seriously. I have no idea how those numbers are anywhere close to reality. They make no sense. The specs I posted of the R5 are also at the lobe, not the valve. At .050 lobe lift it has 243/235 duration. If those numbers he posted are accurate, the F4 has 30+ degrees less duration than the R5 at .050'' lift and I seriously seriously doubt that.

Well, this is where things will get Very interesting. Cause IF what you're saying is true, that would mean the R5 has about 280/272 @.050, at the valve, which would also mean that it has over 350/350 advertised which I Highly Doubt.

Why do I Highly doubt it? Because it would mean that, Other than lift, it would be a Wilder cam than the Mechanical that Warren is running!

Which would Also mean that it would be in the neighborhood of 8000rpm and No bottom end at all!

Now, don't get me wrong, I'm Glad you said that, as that is EXACTLY what this thread is here for. To Straighten up all the confusion and BS out there. Not saying the BS and confusion is on purpose, quite the opposite. I believe it is simply Ignorance over the years that was Never understood, to the point where #'s were getting thrown left right and every other direction.

So, will be interesting to see what the #'s say when any Real measuring takes place

BTW, the F4 duration @ .050 #'s Are the Real deal, confirmed it myself. So Those #'s you can take to the Bank, but like I said.....at the lobe.

[moparzrule]

Well, a good point but on the cam card I posted it only gives specs up to .250 lift....because the cam has ~.280 lobe lift. How could it be talking about duration at the valve when it maxxed out at .250 on the card? It's impossible to be talking about at the valve. otherwise it would give duration specs all the way to .500''.

If anyone local to me can measure the R5 for these specs, I'd be happy to bring it over.

On another note, does anyone KNOW what our rocker ratio is? I've searched and searched and I see anything from 1.7 to 1.8 mentioned. So I'm guessing somewhere in that range, but would like to know exactly what it is.

[Shadow]

Well, a good point but on the cam card I posted it only gives specs up to .250 lift....because the cam has ~.280 lobe lift. How could it be talking about duration at the valve when it maxxed out at .250 on the card? It's impossible to be talking about at the valve. otherwise it would give duration specs all the way to .500''.

If anyone local to me can measure the R5 for these specs, I'd be happy to bring it over.

On another note, does anyone KNOW what our rocker ratio is? I've searched and searched and I see anything from 1.7 to 1.8 mentioned. So I'm guessing somewhere in that range, but would like to know exactly what it is.

Funny you said 1.7- 1.8 because 1.75 is what I use. (or 1.74x would have to look where I wrote it down)

I hear what you're saying on the cam card, but since almost None of this makes any sense, best we Stick with it to the End and Finally make sense of it All! lol

I would also like to mention that with this much confusion, it should be Clear to see that our vendors were only posting what was given to them and really had no idea of the accuracy or Lack of that existed. (simply posting the specs given and Trusting that they were given Correctly)

So no matter how any of this falls, I just want to say that neither Chris nor Cindy should be looked at like they did something Wrong. I think Chris has done the best he could under the circumstances and IF the cam card is Inaccurate, it is the Fault of the Co. that did it.

I Will be doing a thorough degreeing on the F4 And the Taft S3 shortly, so IF someone can do the same on Matts cam we could Really start something Good!

Then add to that, anything anyone else want to contribute and we may just have a Cam database after all these years

[4 l-bodies]

Well, a good point but on the cam card I posted it only gives specs up to .250 lift....because the cam has ~.280 lobe lift. How could it be talking about duration at the valve when it maxxed out at .250 on the card? It's impossible to be talking about at the valve. otherwise it would give duration specs all the way to .500''.

If anyone local to me can measure the R5 for these specs, I'd be happy to bring it over.

On another note, does anyone KNOW what our rocker ratio is? I've searched and searched and I see anything from 1.7 to 1.8 mentioned. So I'm guessing somewhere in that range, but would like to know exactly what it is.

Matt, Rob beat me to this. Yeah I seriously doubt the specs you listed are lobe lift. The #'s I listed for the F4 make perfect sense (to me anyhow) now that we know they were listing .050 lobe lift and not .050 valve lift. In post #349, you are comparing F4 lobe lift @ .050 to the R5's probable valve lift at .050. That is why the R5 looks so much bigger (which even you doubted). This is why I have said from the very beginning that we need to degree these camshafts installed and not using some Cam-Pro #'s generated on a machine (that was designed to measure a translating follower), that are not easily checked or verified as installed at the valve.
Our roller follower ratio is 1.75:1 at max valve lift. That is quite easy to check with a dial indicator. There were at least two different OEM suppliers out there. One had rounded corner and other one had square cut corner at lash adjuster end. I seem to remember measuring one @ 1.77:1 but new followers seem to come in at 1.75:1 at max valve lift.
Todd

[acannell]

How is lash set to zero using the solid adjustable lifter without setting positive lash and forcing the valve open?

I'm thinking you could take a stock lifter, fully drained, then confirm that its preload (displacement into itself) is correct when installed and operating under the base circle. Then take it out, measure its length and adjust the solid lifter to correspond to whatever the length the stock lifter would have been in its preloaded state previously measured.

Or would it make more sense to adjust the solid lifter length to what would end up creating nearly 0 lash? Since the solid lifter wont "bleed" and the gap between the lifter plunger and follower will only tend to decrease off the base circle, then it would seem that setting to a zero or nearly zero gap would work okay, yes?

So in that case, you'd set it to whatever the stock lifter length measured to, out of the head, minus how far it was compressed at the stock base circle, and that would give you zero lash.

EDIT: wait a second maybe those two "ways" are actually the same..yup I think so. Stock lifter length when at the base circle = zero lash length. So setting the solid lifter to that sets lash to zero. There is no alternative that gets closer to zero. A length longer or shorter will increase/decrease valve lift proportional to the follower ratio, yes? But a very small amount since the follower is nearly horizontal at that time. So a 5 thou gap would probably affect valve lift 5 thou (total guess).

[Shadow]

The solid adjustable lifter is able to be adjusted In Place. So you adjust it and check lash till you get what you're looking for and freeze it there.

[moparzrule]

I just don't see how this can be anything other than lobe lift, lemme post more of the card-




It says straight out that that the lobe lift is .280/.287, then gives duration specs that stop before .300''. Makes zero sense if those duration specs are at the valve.

Todd, do you have plans to measure an R5?

[acannell]

The solid adjustable lifter is able to be adjusted In Place. So you adjust it and check lash till you get what you're looking for and freeze it there.

Ahh okay. Lash gap measured by feeler between roller and lobe at base circle? And do you shoot for zero lash or slightly more or less and why? It would appear that a few thou lash would translate to only a few thou error in valve lift measurements. And would be divided by the follower ratio to have even less of an effect.

[acannell]

I just don't see how this can be anything other than lobe lift, lemme post more of the card-

It says straight out that that the lobe lift is .280/.287, then gives duration specs that stop before .300''. Makes zero sense if those duration specs are at the valve.

Wouldn't duration at full lift be zero degrees? And if so, then stopping at some point before that seems to make sense. ??

EDIT: Oh I see what you are saying nevermind. Because it would clearly have more than 0.280/0.287 lift at the valve an so the cam specs could extend much further into the 0.3", 0.4", etc..right?