Changes to my 1835

[apensity]

I'm having a bad kncoking/tickeing noise coming out of a newly acquired 1835. I'm taking it into my local v-dub specialists who build VW drag cars. However, i am looking for speed and reliability (I know I can't have "cost" too, as I have to pick one of the three :^). So here is my current build:

• German Case
  NOS German STD/STD Crank
  NOS German Rods
  NOS Steel Backed Main Bearings
  NOS Shadek 26mm oil pump
  Engle 110 Cam
  Lightweigth Racing Lifter
  Mahle double thrust cam bearings
  Chromoly push rods
  AA thick wall 92mm P&C cut for 94 case and 94 heads
  AA heads 40x35.5 cut for 94 cylinders, 49cc chambers, stainless valve with rev springs, chromoly retainer
  Scat solid rocker shafts, 1:1 rocker with swivel foot adjusters (just had one break a few weeks ago)
  AA lightened flywheel
  1 1/2 quart deep sump
  Doghouse oil cooler
  Petronix SVDA
  Bosch plug wires
  NGK 12mm plugs
  Brosol fuel pump shimmed to 2psi
  Dual 40mm Kadrons with rebushed throttle bodies
  Scat Universal Linkage
  Empi GT Exhaust
  German Sachs clutch, pressure plate, throw out bearing
  3.88 Ring and Pinion

Here are the changes I will definitely be making:

• 3515 A-1 Sidewinder Ceramic Coated Exhaust (1 1/2") with Flanged Heater Boxes or CB3644 1 1/2" Flanged Pro-Flow Street System with large heater boxes (1.5") - to allow the exhaust to breath better
  Check deck height (.050)
  Install 1.25 rockers
  Install HD springs (or duals?)
  Possibly P&P/Blueprint (talk me into it please ;^)

If head is ruined, then I may do this as well:

• Steve Tims 37x32 Super Stocker
  Possibly going to a 2110
  DPR Counterweighted crank

Here is a video of what it sounds like with the knock/tick:

Any suggestions or help is greatly appreciated! Thanks guys!

[Marc]

I'm unable to identify the noise from this distance, if I were there in person I'd probably be jacking up one side at a time and running the engine briefly with a valvecover off to see if I could "feel" the noise in the valvetrain.
The most likely cause for an adjuster breaking is a problem with rockerarm geometry; not saying that's directly related to the noise but it should be double-checked.

I'm not a proponent of running 1.25 rockers on the W-series cams (the grind design predates their existence; the "safety margin" built into the ramps is all but gone at the higher ratio...but they'll work).
The W-110 is on the cusp between using HD singles and a light set of duals - with a light valvetrain singles are often just fine, but the addition of heavier adjusters and steel/CrMo pushrods may necessitate duals...and that's with 1.1:1 rockers.

You can expect a few headaches if you go with the 76 stroke; "A" pistons could have clearance issues at BDC, and you'll need ~.140" cylinder base spacers/shims to maintain nominal deck height at TDC. Engine gets wider, enough that longer pushrods will probably be needed. Compression ratio goes up significantly, you'd need to add ~6-8cc of unswept volume to keep it where it is now.
Switching to "B" pistons introduces problems as well, in that case you'd have ~.140" too much piston deck and need to have the cylinders shortened (again changing req'd pushrod length) or switch to longer connecting rods (possibly both).

The Kadrons aren't a bad choice overall for a "street" 1835 but you'd get more top-end power with more carburetion - that'd make more difference than upgrading the heads IMO. Dunno what you've got room for with the A/C, perhaps you could get bigger throttle bodies for the Kads. An 1835 w/Kads that's not being flogged can get away with the stock heater boxes but I'd upsize 'em if it's in your budget - by all means do it for a 2021 or 2110.

[apensity]

Thanks for the feedback, guess I'll stick with the 1835.

Going with the 32mm vents (heard the 32's run well with the 40 Kadrons, though everything I read says go within 4mm of the carb size, so that would be 36mm vents, but I hear thats a bad match with the kads) and 1.5" from headers to exit (with larger heater boxes) since the exhaust seems to be backing up and causing overheating

[Marc]

The larger heater box pipes are still smaller than the rest of the system but they will help with head temps. Note that they have no heat-exchange "finnage" like the stockers (they're just pipes in a can) so you won't get as much cabin heat, but the resultant low restriction to air flow yields decent defogger action.
Dual-singles don't follow the same rules-of-thumb as one-venturi-per-cylinder carbs. I wouldn't go larger than 32mm vents for a street 1835, and the stock throttle bodies should be sufficient for your purposes too. If you go larger on either you should get more top-end power but driveability/low-end throttle response will suffer.

[apensity]

Nice info.
So the 1.5" heater boxes and headers are smaller than what is needed? I thought the 1 5/8" was too large? Or are you saying that the heater boxes aren't a true 1.5"?

[Marc]

...are you saying that the heater boxes aren't a true 1.5"?

They're about the same size O.D. as the I.D. of the 1½" header tubing.