First engine build! 1776 with a pushrod question

[eccentricvelo]

Hi all,

I acquired a fresh 1776 long block from a buddy who is getting out of VWs. Since it's been sitting for a long while, I've torn it down, checked clearances, and made sure everything generally is correct. So far so good. As I'm getting things buttoned up, I'm trying to figure out the rocker geometry. Forgive me if I use incorrect terminology or if I'm doing something obviously incorrect. I'm comfortable with regular maintenance, but this is my first complete engine build.

The cam is a Webcam 163 with 044 ported heads and 1.25 ratio rocker arms. According to my calculations, the lift should be .479, but in practice it's closer to .494 - is that too far of a difference?

I am having a really hard time trying to figure out the rocker geometry. The photos I've attached are at half lift at .247 and the numbers are the amount of shims under each stand in 0.030 increments. I think the pushrod length may be the culprit? I have an adjustable one on order, but I want to see if I've missed anything else in the meantime?

Using 1x 0.030 means I have 0 adjustment - I can only just barely set 0 lash on #2 exhaust.
2, 3, and 4x 0.030 - photos are attached
5x 0.030 - the adjusters are all the way out and flush with the locknut. This felt wrong.

Pushrod is 277mm long from tip to tip.

Any tips?

Thanks in advance!

[/img]

[94touring]

I believe I've read that the scat 1.25s are closer to 1.3, which explains your readings. I just went through setting up rocker geometry this past week and you really need that adjustable push rod tool. In my situation aside from some shims, I was also required to grind down the face of the rocker arms to back them out a bit more.

[bsairhead]

Pic. 2 looks really close to me.

[modok]

.060 looks a bit short, but close enough.
Might grind the rockers just a touch to gain more adjustment room, will "work", I can't believe scat doesn't machine the end of the rocker square
.090 looks best IMO but will need a longer pushrod.
.120 looks ok but will need a longer pushrod.

I don't think they can ever be perfect, but good enough.
Shim up until the ball to the shaft is about 90 degrees at half lift, then adjust the pushrod to get the adjuster out the right amount, and there some wiggle room for fudging one to fix the other.

OR adjust the adjuster right, then shim out until it's 90 at half lift, and find pushrods to fit.

Both ways should end up same result, assuming rocker is made right, which it roughly is, as in close enough, it isn't perfect.

.060-.080 is typical, so I'd go with .080
also known as 2mm or 14 gauge.

[RandyV]

One more thought....(to my eyes)....

Order up some lash caps (I prefer CB's) and that'll get you a hair more into the fat of that .090" stack and will also get the nose of those adjusters off the edge of the valve stem. You don't need to be dead center (or even want to be depending on who you ask) but I'd like to see it within the circle of the valve stem and with some lash caps you'll help on both of those fronts.

You might also consider ditching those particular swivel feet for some real elephant feet too as some folks here will tell you they really shouldn't be used with higher lift cams. (Some don't even like them over .400 lift and you're closing in on .500)

[Dan Ruddock]

I would go back to stock 1.1 rockers. That is too much lift for stock style rockers. If you really want that much lift use the 1.3 Porsche style.

[eccentricvelo]

Thanks so much for the info! I'll order some lash caps and I'll probably need to order some new pushrods.

CB says they don't recommend their elephant feet for high lift cams over .470. Any other options for different adjusters?

[Alstrup]

,470 is a good safety set up. I have done 0,494" with elephant lifters. The geometry has to be bulls eye, or there will not be enough travel in the foot.

that said, you need to work on your geometry. Your adjusters are too far out. you should aim for apprx 1,5 turn from fully backed out. Also, if you want to continue with stock style rockers (Which I dont see a problem with as long as evberything clears) you should machine the iunderside of the rocker arms so you can back the adjuster further. The difference will be about 2 maybe 2,5 mm and will do a massive difference to your set up, in a positive way.
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[74 Thing]

Yes, grind the rockers on the underside for more clearance then back out the adjuster a bit more and then re do the rocker geometry.

https://www.thesamba.com/vw/forum/album_page.php?pic_id=1403979

[eccentricvelo]

[Alstrup]

[John Connolly]

Those rockers are not back-cut yet, that's the problem. Back-cut .100" (2.5mm). clean, then re-mock and measure.
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[modok]

[Alstrup]

Good catch. I forgot that Scat does odd sizes on the adjusters.
We are approaching than Dan gets his will
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