Its interesting to note on aircooled.net that they mention needing upgraded springs. The rubbish idle is one thing, that is one thing to do with a different cam profile, if you dont stiffen up the springs then you are effectively running a cam with e.g. the inlet valve hanging open for longer and longer, reducing compression the faster you spin the engine... This cam is similar to the Engle W100 grind, it will work great even with the stock carburetors or FI, but it also shines with dual 1bbl carbs, or a single 2bbl. This is a nice upgrade on stockish engines, it's an outstanding bus cam! HD Springs are required! This cam works best with Compression from 7.5-8:1. Power band is from off-idle to 4000.
I have fitted the Scat HD springs during the build. The lumpy running smoothes out as the revs increase. I would say over 2000rpm it sounds smooth.
You need to upload to youtube then paste the link into your post... video appears when you post it up on here Sent from my SM-T580 using Tapatalk
Please let me know how you get on with your checks. I studied Deffer66’s video “wheres your timing at” closely last night and compared it with pictures i took of my cam position at number 1 TDC. Position of cam does look correct. You could post the video on YouTube & send me the link or title.
..yeah I no..I did it before but for some reason yt wont allow me to do it ..anyway I will be tinkering on my bus this afternoon for sure so let you no but honestly doubt in success ..it is the only thing on my bus that really annoys me despite Im „in the business” for over 25 years so have some experience only with type1s tho Sent from my iPhone using Tapatalk
I know it gets very frustrating. I am also in the business, Diagnostic tech. More plugging a computer in though on modern vehicles. I remember carbs, points & condensers from back in the day but was cutting my teeth as an apprentice back then.
if your idle is lumpy it might be because the cam duration is too long, it would make sense to confirm (measure) what sort of cam you have before putting it into the engine - some of the more aggressive camshafts hardly idle and are gutless until 3-4k rpm.
It’s a Scat C25 Cam which i was informed is mild. Other folk on here who have used a C25 don’t seem to have had an issue. Beginning to wish i had just opted for a standard grind now.
you cannot tell the cam timing by looking at it, is your cam is stamped (not casting marks but stamped on the flat where the wheel is bolted on? if not it could be anything.
I presume its a C25 thats what I purchased and what was written on the box. You say the flat where the wheel bolts on, would Scat have stamped there C25 ?
they often do yes, otherwise I would measure it to confirm what it actually is. https://www.thesamba.com/vw/gallery/pix/984637.jpg https://www.thesamba.com/vw/gallery/pix/965555.jpg
..yeah that could be the truth in my case anyway..I could had been given a NON std camshaft therefore the rough idle issue..who knows.. Wysłane z iPad za pomocą Tapatalk
if you fancy, you could do it while in the engine, you need the dial gauge, remove pushrods and tubes, make sure you have a way of measure the degrees of the crank (cam).
The c25 in a type 4 2.0L has a smooth idle. Spray some easy start into both carbs while its running and see if the shake stops. do it 1 carb at a time.
..well here’s a short video of my bus running..I did it yesterday still plan to go out if only weather permits.. Wysłane z iPad za pomocą Tapatalk
I’ve had carbs off. Cleaned, blown out & rejetted. Tried 55 & 60 idle jets. Balanced at idle & at 3k rpm both sides drawing equally. No significant difference.
