[565CamaroSS]

Checked the spring rates on the Comp 948 springs last night, using a cheap, simple, Proform spring tester I ordered from Summit.
Just to get a baseline and to see how close of a reading the tester gave me to Comp’s stated seat pressure of 336# @ 2.10” I.H., I first tested the full triple spring with the retainer installed. At 2.10” it showed 340#, so it seems pretty close to what it should be. In any event, it gave me a baseline.

Next, I removed the inner spring and tested it again with the retainer installed at 2.02” and got 300#.

So, based on what I’ve learned on this thread, I can use the 948 converted to a double spring, and install it at 2.02-2.03 and that will be better than using it as a full triple spring installed at 2.10.

So far, I’ve installed 4 of the intakes at 2.03”. With the standard locks, there’s plenty of clearance between the rocker body and the retainer:

BUT, note position of roller tip on exhaust valve…

I haven’t installed the exhaust springs as yet, because after carefully checking the stand heights again, it looks like I will have to use lash caps to get the right rocker geometry on the exhaust rockers, since I can’t get the stand any lower and the rocker tip is too far back on the stem even at the fully closed position. As you can see below, using the T&D #750 checker tool, the tool is showing zero clearance between the rocker shaft and the tool, although I’m supposed to lower the rocker shaft by half the difference between .750 and .816. That’s with the stand sitting directly on the pad, with no shim under it:

So, I threw a .080” lash cap on it, rechecked the clearance and moved the rocker through its full range (closed to .816”) and it looks much better in terms of sweep and position on the valve tip and at mid-lift (measured) the roller tip sits right in the middle of the lash cap.

Exhaust valve half open:

Exhaust valve fully open:

Please let me know what you think.

But before anyone says anything about I need to machine the heads or buy new valves, let me say that’s not happening, because one of these heads (which I just got back from Brodix in December) is on the motor already and the valves are brand new Inconel valves that I just bought from Brodix when they reconditioned my heads.

So, on the premise of a man has to do what a man has to do, it looks like I’m going to be running lash caps on the exhaust. The only problem is that I don’t have locks that are recessed for the lash caps (I’m sure I do, somewhere, but can’t find them), so I’ll have to order some from summit. Always fun, these projects…

 

[565CamaroSS]

The other thing that I want to mention in here is that it seems that Comp uses the .060” from coil bind rule of thumb as well, at least for computing max lift, based on their published specs.

I say that because based on their specs, the 948 spring has an installed height of 2.10”, coil bind @ 1.13” and a stated maximum lift at .910”

Thus:
2.10 - 1.13 = .97
.97 - .91 = .060

So, by my calculation, 2.03“ I.H. on my intake valves should work (assuming that C/B is 1.13):

2.03 - 1.13 = .90
.90 - .836 = .064

 

[565CamaroSS]

I would advise that you send these photos and script to Sheldon at T&D. They may offer shorter stands. I would call him first, though. Have valve length and as much information on what you have when you do. Are you using Brodix recommended valve lengths?
You are too far to the intake side on the exhaust valve with respect to the roller contacting the valve at full lift by a good bit. Do the intakes look the same?

Thanks.

I'll see if I can reach T&D and see what they say.

The valves are the exact length specified by Brodix for this head, both intakes and exhaust.

The intakes look better than this, although they aren't perfect either. I'm using a .040" shim under the intake stand. The T&D kit only included .080' and .040 shims. Not sure how you're supposed to get it accurate with just those two options...

The roller tip is perfectly centered in the middle of the exhaust valve stem at mid-lift with the lash cap in place, but it does move inboard a bit at max lift (.816"). It's far worse without the lash cap in place though.

 

[565CamaroSS]

Go on the T&D website, look for the installation tech. section, video tech 101 , something like that. There is a video where Dragzine interviewed Sheldon Miller, tech guy at T&D. This article in tech101 shows different scenarios of problems, why, and what to do.
In the T&D catalog, the application charts for Brodix heads, show installation notes, I've noticed Brodix heads requires what I seem to remember was something like "machine work required not normally done at home" or some shit like that. I'll look and see what it says & let you know in a few minutes.
I noticed where you said the other head is already installed, let me make a comment about myself.
I'm kind of a prick, (as I've been told), I will go to whatever lengths needed to make something "exact", even to the point of working myself almost to exhaustion, and pissing people off.. It may have something to do with being of German descent, BUT, I can honestly say, it has served me well so far. "Yes, I worked my ass off for awhile, but now it is exact!". Just saying....

Thanks man. I have watched that video and read all the documentation I could find on setting the stand height, including stuff relating to Crower and Jesel.
The machine work that was necessary for the T&D rockers was done by Brodix at my request. Apparently all the 3XTRA heads Brodix produced since 2012 came with that machining work, but my heads are circa 2008, so I needed to have it done. Basically, the corners of the spring pads needed to be cut back as shown in the photo below:

But Brodix certainly knew I was going to use the T&D 3128 rockers, because I literally asked for the necessary machining for those rockers to be done to my heads. They certainly didn’t tell me there would be an issue with those rockers and that length valve, although I’m really not trying to blame them for anything. And I don’t know if the pads can even be machined down without weakening the heads/rocker mount?
A longer valve would solve the problem, but would prefer to change the stand height if that’s possible.
As far as you being a prick, don’t worry, I’m probably far worse, although I admit sometimes my laziness displaces my desire to be meticulous. I get the German thing though. The wife’s one of them and we spend a month or so there every year, so your thinking is probably spot on on that count.
God help me…if I have to pull that head back off, I’ll probably sell the whole damn thing.

 

[565CamaroSS]

Sounds like your close to letting her rip and hopefully not R.I.P

LOL, hopefully not the latter: “reduced into pieces”

 

[565CamaroSS]

That rocker set doesn't show anything in the footnotes saying machining required not normally done at home.
Using the .750 tool, my figuring, your shaft should be below the tool .043 for the intake and below the shaft .033 for the exhaust. Are you getting this? Either with the lash caps or without?.

Your calculations are correct, according to my understanding as well.
Yes, I’m getting close to .043 on the intakes (with the 0.040 shim under the intake stand) and I somehow stupidly forgot to measure the exhaust with the lash cap on. I’ll do that and report back.

That little T&D measuring tool is a PITA to keep in position though.

The Jesel one is nicer and you don’t have to rip a rocker apart to get a shaft to measure off of.
WTF can’t T&D include a dummy shaft like Jesel does with their tool. I like that the Jesel tool goes over the valve stem too. BTW: the Jesel tool can’t work with the T&D rockers, because the shaft on the jesels are smaller in diameter.

BUT, here’s the thing that really got me scratching my head: the Jesel tool instructions say the tool is for valve lifts between .600 and .800”, and if you’re over .800, you should remove .050” of shim?! So, if my cam was .800” lift, I’m good, but if its .816”, it needs to be adjusted down by .050”??? Really? Somethings not right with that…

So, I’m starting to wonder if I’m not being to fussy about the precise height of the stands being absolutely spot on? There’s no way to achieve that anyway, without a million shims, of various thicknesses, instead of a stack of .080 and .040 shims.

 

[565CamaroSS]

Please don't take this comment as arrogant, but you are overthinking this. First of all, you're saying you intakes are real close with the .040 shim. OK, the intakes are DONE and correct. Stop thinking about the Jesel stuff, you got T&D....I'm assuming you have the 1 piece intake stand, right? The exhaust stands are 4 each per head, bolt to the head and have the small bolts that bolt to the intake stand. Is the exhaust shaft lower than the tool, with the lash cap, measure with a feeler gauge. What is the measurement? I know the little flat tool is cumbersome to hold with the lash cap on, but It can be done by holding down somewhat on top of the tool keeping the angle against the side of the lash cap.
I went thru all kinds of bullshit when I converted from rocker studs to shafts on my old GM Bowtie heads, then when those heads destroyed themselves and could not be repaired, I bought Dart 355 cc. bare, and started all over again with a new set of T&D's. Just part of the fun....
Again, shaft below the tool by .043 intake
shaft below the tool by .033 exhaust with the lash cap right now, nothing else matters....

No worries man. I’m grateful for the assist.
I understand what I need to do.
I just checked the intake again and it’s not .043, and without a different shim set I can’t get to that number. It’s closer to .035” as best I can measure it. That’s with a .040” shim under the intake stand.
On the exhaust without a shim and the lash cap on it, the gap between the tool and the rocker shaft is too big, something like .070. So I stuck a .040 shim under that stand and it’s pretty close to perfect at about .032 - 0.35.
It is a bitch to hold the valve up without a spring on it, whilst keeping the tool square against the valve stem and measuring the gap with a feeler gauge. But it looks like I’m getting there.
Thanks again for your help.

 

[565CamaroSS]

OK, so you're off on the intake by .008, you're good there.....
Now you're off on the exhaust by a whopping nothing.....
Remember to check your stand bolts for proper length, need them as long as you can without bottoming out.
Also, use pipe sealer on your stand bolts, I use Rector Seal 5, available at Home Depot, if you have Home Depot in the Cayman Islands.
The fun will continue with the pushrod length......

Yep, I’m thinking that’s as close as I can get them. Checked the sweep and that looks decent on both.
The stand bolts are good. The intakes stick slightly into the intake ports and the exhaust stand only has that one 0.040” shim on it, so I’m sure that there’s plenty of engagement.
I was wondering if I should use blue Loctite on the stand bolts, since I noticed that a lot of guys use that for sealing NPT threads on nitrous fittings these days?
I typically use Locktite brand Teflon thread sealer for that kind of thing though. Might just stick with that, if I can’t find the Rector Seal 5 stuff.
We don’t have a Home Depot brand store, but between the various home supply and automotive stores we have here, we pretty much have any sort of product that you can find in the US. What we don’t have, unfortunately, is a decent modern machine shop, IMV.

 

[565CamaroSS]

Why not have someone mill the bottom of the exhaust stands to get your correct height... I do it all the time.

Don't worry too much about location of the sweep on the valve within reason, you want the smallest sweep pattern period.

Thanks. I was thinking about that, but the instructions warn you not to do that, although I can’t see how taking ~.030” off the bottom could compromise them. If I had a bigger can and >1000# springs, then maybe.
But, I will probably just use the lash caps, which I would have to use if I had Ti valves anyhow.

 

[565CamaroSS]

I like the Rector seal because it never hardens, stays pliable, and it really seals. I've never tried the Loc-Tire Teflon. If it stays pliable I'd use it. One other thing to remember in dealing with pushrod picking in your application, is the 210 degree ball end with the lift you have. Also make sure your heads have large enough holes in them if you are considering 7/16 in. diameter. BigblockMark has experience with that can of worms issue....
Got a question for you, isn't the Cayman Islands kind of known for the beaches, beautiful women in thongs on the beaches, and whatnot?....why fool with cars and the like, when you got that?....just saying.....

Hahahaha! We’re actually known for “tax avoidance” for our resident wealthy retired millionaires and billionaires and the consequent highest cost of living on earth, last time I checked. I live about 100’ from the beach, and trust me, it’s nice, but gets old in a hurry. This place is very small and boring, so I do this kind of thing to keep my sanity.
I think I have the clearance for 7/16” pushrods and will definitely get the 210 degree tips. I’m thinking of ordering the series 5 from Manton,once I measure the length properly.
Thanks for all your help.

 

[565CamaroSS]

Smith Bris actually make very nice 210 pushrods too. A while back, no one but them has the tubing to make certain diameter and wall thickness pushrods. Could be better now.

Thanks. I know about Smith Bros. They’re certainly an option as well. I’ve dealt with Manton before and they treated me right, so I’ll give them a call first. Smith Bros are also up in Oregon, IIRC. When you’re overseas like me, sometimes you have to make a purchase decision based on costs of shipment, because shipping can get expensive, so returning stuff is almost cost prohibitive and customs here will still charge you 25% import tax on the cost of shipment.

 

[565CamaroSS]

LOL, they say alit in them instructions, ask them why the hell you gotta cut them, why the hell they don't fit per your application..... You'll get crickets...
I was onec told they had no stands that fit a brodix bb4 head... But listed one for a bb5... I told Sheldon it was the same... He insisted no, till i sent him the picture of them on the bb4...
I've cut exhaust stans .060 already with 1000 psi open pressures and never ever had a problem.

I'd cut the stands.

Thanks. I hear you on the disclaimer/warning on everything approach. Most likely they’ve been advised to put that in their instructions by their lawyers, lol.
It is reassuring to know that you can machine them. Hell, come to think of it, how thick is the outer lip on a retainer, and they seem to hold up fine, no?
My only problem is that if I take them to one of the cobblers that we have around here that call themselves machinists, they’ll probably just fuck them up and I’ll be buying a new set from T&D anyway.

 

[565CamaroSS]

Wanted to post this diagram up that I just pulled down off Manton’s website, which is very instructive.
This is also what I’m seeing now in terms of movement across the valve tip.

 

[565CamaroSS]

No worries man. I’m grateful for the assist.
I understand what I need to do.
I just checked the intake again and it’s not .043, and without a different shim set I can’t get to that number. It’s closer to .035” as best I can measure it. That’s with a .040” shim under the intake stand.
On the exhaust without a shim and the lash cap on it, the gap between the tool and the rocker shaft is too big, something like .070. So I stuck a .040 shim under that stand and it’s pretty close to perfect at about .032 - 0.35.
It is a bitch to hold the valve up without a spring on it, whilst keeping the tool square against the valve stem and measuring the gap with a feeler gauge. But it looks like I’m getting there.
Thanks again for your help.

Just for the sake of accuracy, I wanted to report in here that I did a very careful re-measurement of the rocker heights tonight. I discovered that the intake actually didn't have .035” of clearance between the tool and the rocker shaft with the .040” shim under the stand like I stated, but only close to .010”. I have no idea where I got that from. Maybe I confused the intake with the exhaust.

So, I took the shim out and bolted the intake stand directly to the head, and remeasured the gap and it came out to .046-0.050”, as measured with a mini feeler gauge. I made sure to keep the checker tool square and the intake valve up, so I’m sure that’s as accurate a measurement as anyone could get with the tool.

Then I put a checker spring on it, used a marker on the valve stem and rocked the valve open several times as close to the full lift as possible. I used a checker spring on it and measured the open height with a caliper. I took a picture of the pattern on the valve stem, and it looks pretty good to me:

So, it looks like the intake stands are actually pretty damn close to where they need to be without any shims under them, and I’m pretty sure that I’m going to install it without any shim under the intake stand. I’ll check the other head to make sure it’s the same.

Then on the exhaust, I decided that although I only have about .005” between the tool and the rocker shaft without any shim under the stand it, even though I need .033” of clearance, I would try it like that (without the lash cap) and use the Manton instructions to see where the roller sits on the valve stem at closed, mid-lift and full open.

The weird thing is that the sweep on it looks very close to what I’m seeing on the intake. So, although according to the T&D instructions, the stand “needs to be” lower, the sweep across the exhaust valve looks pretty damn good anyway (according to the Manton diagram). So, I’m wondering now if I shouldn’t run it like this or whether to use the lash caps and shim the stand to get the desired .033” clearance?

Here‘s where the roller tip sits with the valve fully closed:

And here’s where it is with the valve fully open ( I measured the open height with a digital caliper):

So, since I’ve ordered a bunch of shims, some .060 lash caps and the recessed locks, I’ll check the sweep again with the lash cap and some different shims once I get those things, to see if I can get as close as possible to the required .033”, but I’m pretty sure I could just bolt these damn exhaust stands on without any shims under them and let it eat without any problem.

 

[565CamaroSS]

Permatex #2 nonhardening brown sealer in a tube works for rocker stud threads. Shelden at T&D has exchanged stands with me for $200 for special stands. Had to move rocker bolt positions up .040" to get pattern in center on valve stem before on Dart and AFR heads. Still offset left to side .030" on stems after that. Tuff to get done from out of 48 states? On shaft rockers pushrod length or lash caps should not be needed to get pattern correct. Stand height is all you need. Just measure for pushrod length after pattern is correct. Don't even need heads on block to do. With checking springs, just lift rocker thru sweep. I use red dry erase markers for checking pattern on stem. They don't supply less than .040" shims because they will deform under use according to Sheldon. The .080" shims can be ground on a magnetic base surface grinder to less thickness.

Thanks for all of this. I read your thread on your struggle with setting up your rockers and what I have here is nothing compared to that, I think, lol.
After what I saw last night, I wondering whether the reason T&D don’t supply a wide range of shims like Jesel does is because stand height doesn’t change the contact pattern as much as you think.
I say that because on my exhaust valve, the contact pattern or “sweep” of the rocker tip is pretty much the same with the ~ .033” lower stand height (achieved with an .080” lash cap and a .040” shim) as it is with @ ~.005 ( you can barely see a gap) without the lash cap and with no shim.
I get it that you’re not supposed to use pushrod length with a shaft rocker setup, because the rocker height is fixed, whereas with a traditional rocker pushrod length can be used to change the geometry, since the pushrod itself, together with valve height is what holds the rocker in its position.
But I think there’s nothing wrong with using lash caps as a tool to change the valve stem length in order to set the geometry of the rocker shaft. In fact, that’s what Jesel’s instructions tell you to do if you can get the stand low enough.
I’m personally no fan of lash caps, simply because I’m paranoid about having tiny little pieces of metal inside an engine that aren’t fixed or “trapped” somehow. But the truth is that they are trapped and as long as a pushrod doesn’t bend or break or the adjuster doesn’t come loose, they really aren’t going anywhere, sort of like the needle bearings in the rocker fulcrum.
In any event, if I had Ti valves, I’d need to use them anyhow.
The positive thing about them that I see is that they create a wider contact patch for the roller and they protect the valve tip from wear, if that’s even a problem.
I have a set of Jesel shims on the way as well, which includes .025 and .050 shims, so that, along with a set of .060” thick lash caps, will give me the ability to set the rocker shaft height more precisely.
Once I see what that does with the rocker sweep/position, I’ll decide what to do.
Thanks again.

 

[565CamaroSS]

Int sweep pattern looks good, Ex is a little low on the valve tip like you said but not terrible. You could try it as is and just keep a eye on it after its running.

The exhaust sweep without the shim and lash cap (as shown in the pictures I posted last night) looks pretty damn close to the intake. I forgot to take a picture of that, as well as the contact position at mid lift, where it’s just barely past the center on the other side of the valve stem. It’s not perfect per the Manton instructions, but close.

 

[565CamaroSS]

Re: Thread sealant for stand bolts, since the 4 intake stand bolt holes are open into the intake ports in my heads and since I wanted some kind of thread locking compound on the stand bolts, this is what I’m going to use:

Permatex® Seal & Lock Thread Compound, 35 ML – Permatex

www.permatex.com

Seals like their Teflon thread sealant, with the strength of their blue thread lock.

Found it at a local automotive store yesterday. Didn’t know it even existed.

 

[565CamaroSS]

Thanks man. That is all very useful information. I checked the other head that’s mounted on the engine today and the stand heights seem to be identical. That stupid little tool that T&D supplies is a real PITA to hold, especily since the fukin valve keeps dropping when you’re ensuring it, be use you have to take the spring off.
I saw a video a while back where Crower was demonstrating how to set the stand height on their rocker shaft and they had a tool that measured off the top of the valve tip with the retainer on. That wouid make life so much easier.
I bought a Jesel tool the other day too, just for the hell of it, since it was only $16.
That is also a much nicer tool to use, since it goes over the valve stem and basically squares itself.
But the dimensions are different and the even dummy shaft they sell, which is also a nice touch, is a smaller diameter than the T&D shaft.
It would have made my life much easier if the T&D tool was like that.

 

[565CamaroSS]

Yes, thanks very much for taking the time to explain in detail how it’s done. Very grateful for that.
I think your diagram confirms the Manton instructions as well, which dictate that roller tip starts on the “inboard side” (closer to rocker fulcrum) of the valve stem and as the valve opens, it moves outwards away from the fulcrum so that by mid-lift, it’s an equal distance across the center on the “outboard side” of the stem, then rolls back to where it started.
It’s very useful to know what the width of the sweep should be (0.050”) so many thanks for that.
The only reason I‘m considering lash caps on the exhaust valves is because I couldn’t get the exhaust stand low enough to meet the T&D instructions, which call for my exh rocker shaft to be .033” lower (.816“ lift) than the tip of the tool. So I added the lash caps to lengthen the valve and then shimmed the rocker stand to try to hit that number, and I can get real close to it (~0.035”) doing that.
But the strange thing is that I can’t see a better pattern doing that anyhow, although the lash cap is harder to read. But I’ve looked at this damn thing now until I’m cross-eyed, so I’m going to put it together with the recessed locks on the exhaust - so that I can use lash caps if I “need” to - but will use a test spring and roll the motor over until I can get a reading on the valve stem and see what that gives me.
Because at the end of the day, it’s where the roller meets the valve stem, and how much it moves across it that matters.
Thanks again for all the help.

Wait…”pushrod geometry“ you say??? JK, I’m confused enough as it is now, lol.

 

[565CamaroSS]

It makes sense to me as well.

I suppose the way to explain the need for it is if that 90*/90* relationship doesn’t exist, then you not going to get the lift from your cam that the lobe and rocker ratio predicts?

xlcr77, I was wondering the same thing. I’m thinking that if the adjuster is extended too much, it will lower the pivot point of the pushrod, so (in addition to starving the oil flow into the rocker), that will also adversely affect lift, no?