Engine rebuild: Which Cam, Full Flow and Bellows?

[gvee]

I'm nearly ready to start putting my engine back together but before I do that I have to order a few bits and pieces. So I need your advice on a few bits.

I am running a 1641TP with a single 34 carb. I don't know much about engines (before stripping mine down I didn't know a cam from a crank!) so be nice and bare with me :lol:

1) turns out my cam was the point of failure (see here for the pics) so I needs to get me a new one. But what do I replace it with? I've done a lot of reading on this site and the Engle 100 or Scat c25 look like the advisories other than stock. But what benefit can I expect from the non-standard? Oh and 3 or 4 stud, what's the difference? I've noticed that some oil pumps are designed for 3 stud.. eh? How does that one work?

2) I've been advised to go full flow. My understanding of why to do this is that the type 1 engine has no form of oil filter, meaning we have to change oil more frequently. Putting in full flow allows for the addition of a filter which should not only extend the time between changes and oil capacity, but overall engine health should be improved. Am I getting close? Instead of having the case tapped I have been looking at the cheaper options, either CSP full flow adaptor or a maxi oil pump. What do you reckon? Bear in mind I have a '72 and am not sure that the items on the cbperformance site will clear the engine support bar. If I get a new oil pump with dual outlets I don't need any other kit, right? But if I go for the CSP option I need to get a new pump cover with a single outlet, too?

3) What is the bellow-type thing that sits under the push rods on the right (when looking in the engine bay) that has a linkage to the flaps in the fan housing? Whatever it is, mine looks pretty darn crusty! Going to have a go at cleaning it up, but have a feeling it will need replacing. Couldn't find a reference to this thing in my manual so can someone let me know what it is and what its purpose is please?

Cheers,
George

 

[67panel]

CAM,now thats a can off worms ,tbh i think twin carbs would be better with a stock cam than better cam and stock carb,thing is with a "bigger"cam you get some trade of ,loss of low end power and raise the rpm peack power is made at,stock single port in mine but with twin port heads,flowed and port matched and twin itc webers.evan with this you can feel the power coming in(when towing race beep)starting at 2K and comes in again at 2500K to 5500k.
3 and 4 rivet cams make a differance to the oil pump fitted,all after market cams are 3 bolt.
full flow with built in filter should fit ok with late style engine bar.

 

[gvee]

Sadly twin carbs are a no go for me for at least another year. One word: insurance. Benefits of being under 25 :roll:

So bigger cam means I "lose power" at lower revs, but pick it up higher in the range?

 

[67panel]

to some extent ,but you will make more power than you will lose,just higher up rev range.the bellows thing is the thermostat for the air flaps in fan housing ,test it in hot water or with hot air gun to see if it works(opens)make sure all the linkage and flaps are there and free.if you use stock carb you will need to rejet it and its worth porting your heads as well .

 

[lynn71]

personally i would go with an engle 110 cam plenty of power and nice meaty sound i would also got with some 043 heads that have oversized intake valves then top it off with a progressive weber trust me it does wonders for a bug maybe one day ill cram the list of junk into my bus

just remember if you upgrade the cam also upgrade your valve springs and possibly lifters stock springs will break with a 110 cam trust me ive done it

 

[D@VEY]

Hi im about to be buiding my engine soon ive been advised to go with a Web 86 cam from Stateside tuning its got the Low end torque you need to get a bus moving.

 

[67panel]

yes he doesant rate engle or scat cams ,not very accurate.got a webb in our race engine ,just set rocker shims and cut to length push rods this aftey.with ratio rockers its got 14mm lift at the valves :shock: dont think that will work in a bus,cant remember the grind but no power below 3k,well it is a drag motor.I liked the finish on it,better than scat.worth getting the book How To Hot Rod Your Air Cooled Engine.lot of useful info if a little dated but assembly and checking parts still the same.

 

[weeboll]

+1 vote for a scat c25 though i beleive an engle 110 is pretty similar. more power at higher revs and once you've got the heads and carbs breathing more (in other words bigger) then you can rev a fair bit higher too

you do need bigger springs but high lift not necessary so my engine man advises

the thing about the cam is that once its in its in (unless you want to take the whole thing apart again) so when you get bigger carbs in a years time then your well set..

full flow oil filter is a very good idea, if the engine is apart, why not tap the case now rather than an after market bolt on?

never had bellows on any of my engines, those 1641 thin walled barrels are going to heat the whole thing up faster anyway so no need - actually ignore that, 1641 barrels dont create more heat, they just distort/wear more due to greater heat from buses

WB

 

[D@VEY]

When I spoke to James it was more the springs and bits you get with the kits that are around that he doesnt rate. The Cams themslefs are fine.