R3W7 Assembly

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Well, I was all set to grind some clearance notches for the rod bolts into the bottoms of the cylinders....but there's so much room already it looks like that won't be needed.

The Diamond pistons fit the chambers very well....so however they know what the chambers look like, they know.
piston tdc.jpg
piston tdc.jpg


rod bolt clearance.jpg
 
gregcon said:
So, tomorrow I take the block in to get bored and honed.


Ordered the remainder of the valvetrain today after talking to Isky. These heads use a 2.00" installed height, so I went with the 9985RAD springs; these are their 'toolroom' steel springs. I used these as I had a few guys tell me they last and last and last. I discussed the pressures of 245/600lbs and Isky said that 600lbs was heavy but not super-heavy. They're using 1000lbs springs pretty commonly now. I should note that even 600lbs is about 200lbs more than recommended by the various Mopar books I have. I mentioned this and they said, "Those guys are 20 years behind the times" lol.

The retainers are their 92-ST, which are also 'toolroom' steel and are only a tiny bit heavier than titanium. I used these as I am not wild about the long term prospects of titanium retainers.

The locks are VL-700, which are their 7 degree chrome moly steel locks. The Isky guys told me 7 degree locks are their top choice; they sell 10 degree locks to stay in the market but their own testing shows 7 degree locks are best. They did qualify this with the usual 'as long as you're not buying junk parts".

Valve pocket locators are Isky 800-VSL; these work on the W7 head with the 1.565" pocket size.

Shim kit #8, 72 shims in 3 different thicknesses will allow me to set the final compressed height where I want it.

Last, Crower .090 deep lash caps.

View attachment 1715632620
Click to expand...

i used those exact roller springs on my W5 heads.
245/600 pressures, 273/280 comp roller that Dwayne specced. 699/672 lift with 1.6 Jesel sportsman rocker gear.
Shifted it at 7, trapped at 7500. Had hundreds of passes on those springs. 9.80 car that weighed 3350 with me in it.
Springs still checked fine at freshen up. Reran them, were still on car when i sold it. Very nice pieces.
 
Good to hear! My cars do lots of sitting....the last thing I want is a set of springs that 'go away' over time. I think, in general, the old school companies that are still independent have a lot to offer, for just a few more dollars.
 
gregcon said:
Good to hear! My cars do lots of sitting....the last thing I want is a set of springs that 'go away' over time. I think, in general, the old school companies that are still independent have a lot to offer, for just a few more dollars.
Click to expand...

the tool rooms are excellent springs. Its smart running a roller and RPM to not scrimp on valvetrain components.
I backed my rockers off every winter on that car. Dont know if it contributed to the longetivity or not, but it certainly didnt hurt.
Back then i raced a lot more than i do now
 
Made an initial piston-to-valve check, looks like there is lots of of room. The intake is around .235" and the exhaust is even more. I'm going to try advancing the cam 4 degrees then rechecking it. I don't plan to run it that way but I want to get some reference points while it's easy.

PVC.jpg


PVC IN.jpg
 
gregcon said:
Made an initial piston-to-valve check, looks like there is lots of of room. The intake is around .235" and the exhaust is even more. I'm going to try advancing the cam 4 degrees then rechecking it. I don't plan to run it that way but I want to get some reference points while it's easy.

View attachment 1715636489

View attachment 1715636490
Click to expand...


You’ve got more than that if you are using checking springs. You can run as tight as piston to head clearance for intake valve clearance. I’ve run as tight as .055 with aluminum rods. Of course, I run a Milodon gear drive so the timing doesn’t move.
 
No, the check was made with the actual 9985 valve springs and lashed at .020". I also have the head bolted down using a pre-flattened (used ) gasket so the compressed thicknessed will be very close to actual.

This is the first set of Diamond pistons I've bought; so far I'm pretty impressed. Haven't found anything that looks 'off' or needs massaging. I also like how the entire top of the piston is CNC milled, notice how all the edges are rounded. In the past, I've had to go in and do all that by hand.
 
I advanced the cam 4 degrees and rechecked PV clearance.....as expected, the exhaust went up and the intake went down. The intake was at .235" and it went to .204"...still plenty. I don't plan to run 4 degrees advanced but it's nice to know I could, if I wanted.

I haven't messed with the T&D rockers until now, but they're a really nice setup. Much easier to work with than the stock setup. The bracket bolts to the head, and then the rockers bolt on in pairs. This makes it easier to adjust, if you needed, and easier to work on one cylinder without affecting the rest. A couple small negatives...the rockers must be removed before you can access all the head bolts, and the hardware needed to bolt the brackets to the head is very specific in terms of thread length and also head thickness. That's not a big deal, but if you lose a bolt in the mud you won't be running to Home Depot for another.

TD.JPG
 
Here's another nice feature of the T&D rockers....their setup allows the use of a simple height gage that establishes, easily, the proper geometry of the rockers. They sell these gages, but they also give you a drawing in case you want to make your own. Since I didn't want to wait a week to get in a gage, I made one. This compares the height of the valve tip to the centerline of the rocker shaft, and they give you some basic math that allows you to know how much shim to use under the rocker shafts. In my case, with .680 lift, I will need about .100" of shim. Use less shim for higher lift. This is a good thing....it's an indicator that I could run around .800" lift without any machining, if I wanted!
T&D gage.jpg
 
So I spaced up the shaft assembly .100". The shims go between the head and the black anodized rocker support, not under the round shaft itself, so it's easy to make a shim out of flat stock. The pattern looks good. The "IN" means the side that is toward the intake manifold. This is what T&D says they want to see for roller contact....a slight offset toward the intake side when the valve is closed. As it opens, it moves a little toward the exhaust side, then at half lift it begins to move back toward the intake side. The pattern shown is with right around the .680 lift I plan to use.
Rocker tip pattern.jpg
 
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gregcon said:
Here's another nice feature of the T&D rockers....their setup allows the use of a simple height gage that establishes, easily, the proper geometry of the rockers. They sell these gages, but they also give you a drawing in case you want to make your own. Since I didn't want to wait a week to get in a gage, I made one. This compares the height of the valve tip to the centerline of the rocker shaft, and they give you some basic math that allows you to know how much shim to use under the rocker shafts. In my case, with .680 lift, I will need about .100" of shim. Use less shim for higher lift. This is a good thing....it's an indicator that I could run around .800" lift without any machining, if I wanted! View attachment 1715638039
Click to expand...

They used to include that gauge in every rocker set I ever used. I have several in a drawer. I prefer the T&D paired shaft over the single shift stuff any day. J.Rob
 
I bought these new-but-old so the gauge probably is in someone's toolbox.
 
gregcon said:
So I spaced up the shaft assembly .100". The shims go between the head and the black anodized rocker support, not under the round shaft itself, so it's easy to make a shim out of flat stock. The pattern looks good. The "IN" means the side that is toward the intake manifold. This is what T&D says they want to see for roller contact....a slight offset toward the intake side when the valve is closed. As it opens, it moves a little toward the exhaust side, then at half lift it begins to move back toward the intake side. The pattern shown is with right around the .680 lift I plan to use. View attachment 1715638128
Click to expand...


How wide is the pattern?
 
I don't know. I'm gonna do some more checking today. I didn't pattern it with the rocker higher because when I raised them up, the tip wanted to migrate toward the exhaust side. But I haven't made enough trials to decide where I want to end up at. I'll probably call T&D Monday to ask a few questions, too. I know I 'm close, but I know I'm not 'best' just yet.

This is a good example of why I shudder at pre-made pushrods for any engine. As I adjust the rockers, the pushrod length changes accordingly. And, on the T&D's, they are very specific about how much thread they want on the rocker adjuster.
 
@gregcon I hood this question doesn’t annoy to much.

Where & how did you take the pushrod measurement?
 
The method I use is pretty simple...and it's the same as T&D mentions in this document. With the actual cam/lifters/valves, etc. in place I use a feeler gauge to maintain the lash then adjust the pushrod thread to the right length. Once that's determined, I send the pushrod(s) to the pushrod company and tell them to replicate it.

Note how in the T&D sheet it says to establish the initial thread on the adjuster at 1 thread down then never deviate more than one turn from there. It shows the need for an accurate length pushrod, at least with their setup.
http://www.tdmach.com/wp-content/uploads/2018/01/Instructions-P-N-05899.pdf
 
gregcon said:
I don't know. I'm gonna do some more checking today. I didn't pattern it with the rocker higher because when I raised them up, the tip wanted to migrate toward the exhaust side. But I haven't made enough trials to decide where I want to end up at. I'll probably call T&D Monday to ask a few questions, too. I know I 'm close, but I know I'm not 'best' just yet.

This is a good example of why I shudder at pre-made pushrods for any engine. As I adjust the rockers, the pushrod length changes accordingly. And, on the T&D's, they are very specific about how much thread they want on the rocker adjuster.
Click to expand...


I agree with Mike at B3 in that I’d rather have the pattern off centered a bit and get the sweep tighter. IIRC my sweep is .040 an it’s a touch to the exhaust side.
 
gregcon said:
Off centered in which direction?
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To the exhaust side IIRC. When it goes back together I’ll check it again. It’s apart because I went against my gut when putting it together and then jacked up some stuff when I had the shafts off. Bent some valves and dinged up my cam and lifters.
 
So I changed to a .187" shim and it moved the contact 'over the hill' to the exhaust side. It reduced the width by a little, it's now about .070"
pattern .187 .jpg
 
I tried a few more thicknesses on shims; I can move the pattern around but it more or less stays in the .070-.080" range. I should try to find a better marking compound as the stuff I am using is not giving a really clear definition. I think there is some 'pull away' when the roller leaves the face of the lash cap and it's making the pattern look wider than it actually is. I can see some faint lines that look like the actual contact but I am not sure. I guess I'll dig out some different compound.
 
gregcon said:
I tried a few more thicknesses on shims; I can move the pattern around but it more or less stays in the .070-.080" range. I should try to find a better marking compound as the stuff I am using is not giving a really clear definition. I think there is some 'pull away' when the roller leaves the face of the lash cap and it's making the pattern look wider than it actually is. I can see some faint lines that look like the actual contact but I am not sure. I guess I'll dig out some different compound.
Click to expand...


Is that leaded grease? Hard to find that anymore, and I have some stashed away. I use Prussian blue, but it does the same thing.

That .070 wide swipe may be as good as it gets.
 
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