Big Bore issues?

[j.nathan]

Have heard that 1641 and 1679 motors lead to reliability issues, is this true?
If so, what problems do they cause?
Why is a W110 cam not suitable in a Bus?

 

[Clarkson46]

Can't speak for the 1679, but a 1641 has been in the rear end of a '68 Westy for the last 10k with no issues. So what have you heard? Was it it from the bloke in the pub, must be true, the bloke in the pub said so. :mrgreen:

 

[sparkywig]

I can vouch for a 1679 and a 110 cam. Never had a problem, used as a daily driver and family holiday bus.

 

[surf]

Hi, I have a 1641 in my bus, it's a volkspares one and they have got the worst reputation, but I have never had a problem with mine after 5 years and around 15K. I think someone had a problem with one once and it got blown out of all proportion and they blamed the big bore kit or replacment engine, because it is supposed to get hotter because the cylinder walls are thinner.

 

[currylager]

Have 1641 too, been very well mannered so far. I believe the concerns are down to the thickness of the barrels, heat dissipation etc, fable or fact is another matter :roll:

 

[j.nathan]

Thats what i'd heard.
Also that mild cams were not suitable for T2's without using twin carbs??

 

[sparkywig]

I can vouch for a 1679 and a 110 cam. Never had a problem, used as a daily driver and family holiday bus.

Thats what i'd heard.
Also that mild cams were not suitable for T2's without using twin carbs??

I also had the unfashionable/dreaded Weber 32/36 twin choke carb fitted :roll:

 

[mjknight71]

.............isn't there two forms of the 1679cc :? ................one with machine case the other without :shock: ..........

...........I think the one without the machined case (i.e bolt on like the 1641cc) has had negative comments due to (from dodgy memory) the small end bearing being weak :? the machine case has a larger bearing :? :?

 

[currylager]

Not sure on that one :roll: . I am wondering whether it is possible to get a good standard bottom end, machine it out to take 1800 or 1900 B+P, would it be too weak and unreliable for the extra BHP???, or do i have to spend loads for posh crank etc :roll:

 

[the councillor]

:shock:

keith seume's 'air-cooled engine interchange manual' is an excellent starting point for those travelling on the road of VW flat 4 modification 8)