40Hp big bore refresh - cam selection

[gerg]

So it’s been many years since I posted here. I put about 10k miles on my 40Hp since it was built in 2010. Engine always had a noise that irritated me to no end - almost sounded like excessive end play to me. Well, in 2020 I got another lift for the home shop and out the engine came. What I found was unexpected. The cam gear I used has ZERO markings on it - I presume it is a cheap import POS. I had perfect lash in one location and at least .040” 180* out from that . . . Like it was cut off center / out of round.

Built on a ‘65 case, ‘65 square boss heads and 28-PICT up jetted (size unknown right now), W-100 and 1.1:1 rockers. Correct ‘65 intake and distributor (will amend p/n here) and stock exhaust.

Donnie over at Square 1 Restoration has been helping me get things sorted. Many other small issues were found - one being what looks like a bad deck job from RIMCO. He was able to clean the case up perfectly.

What we are using:

83mm big bore P&C
65 square boss heads that he detailed, ported, back cut the intakes, new valves / seats and 3 angle job.
1.1:1 rockers with Mazda style swivel adjusters
.040” deck
Currently 45cc heads (7.9 SCR)
Looking at maybe using a 30-PICT
Vintage speed stock style muffler (curious best place to put an O2 bung for wide band)
Donnie has a VJ 4BR8 mech. adv. distributor - considering using, looking for thoughts (supposed to have similar curve as 019)
Rotating assembly is balanced
Oil galleries drilled and tapped
Hoover mod @ center cam journal
New Engle lifters

I believe Donnie was reading here that the 100 comes alive closer to 8.25:1 CR. He was ready to work the heads to attain that (original plan was to reuse W100) but is now waiting on cam selection before he continues to work the heads.

So the choices being considered are:

W100
W90
WEB 86
CB 2280

Looking for thoughts or suggestions and any other combo optimizations I should consider.

I will get the exhaust, intake and distributor part numbers here shortly.
_________________
Gerg

. . . I got 99 problems and my bus ain't one . . .

'65 Sunroof Beetle
'65 Vert
'60 Singlecab

[gerg]

So I forgot to ad the missing part numbers from above:

Intake 113 129 701 D
Distributor 111 905 205 N
Vintage Speed 40Hp fresh air muffler 111 251 051 H VS
_________________
Gerg

. . . I got 99 problems and my bus ain't one . . .

'65 Sunroof Beetle
'65 Vert
'60 Singlecab

[Bub]

Sounds like a good setup.
And YES, from my experience you'll benefit from bumping CR up a little bit. With the 83's it's noticeable. Don't know how far you want to go, but dual carbs even on that 40hp make a HUGE difference.
8.25:1, street cam, and 83's with anything that gets you better flow and a bit more fuel than the stock intake will add up. People will warn you about the cooking the 83's, and they do run hotter, but we ran them daily in the 80's and 90's and I do not remember any big failures.
I'm running them on a 36hp and the engine absolutely hits some sketchy temps, but it just keeps going.
Also, down the road *if* you can find a BR25 / 010 distributor it does seem to go a bit better than the 019- but vacuum advance will beat any other distributor most days.
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[gerg]

Thanks Bub!

The one reply I can find from the original build was that the W100 was too much cam for the stock intake.

My original goal was a stock looking engine with whatever extra Hp I could get out of it. Felt like it ran decent with the 100, but who knows how much better it could have been.

I am not opposed (at some point) to running a vintage dual carb setup. Likely not happen, but who knows.

So if a milder cam is in order now is the time to do it.
_________________
Gerg

. . . I got 99 problems and my bus ain't one . . .

'65 Sunroof Beetle
'65 Vert
'60 Singlecab