I’m wanting to fit new cylinders and barrels to my heads can I fit the slip in 2056cc ones without affecting the compression too badly? Or should I play safe and go for the 2000cc Sent from my iPhone using Tapatalk
The extra capacity is not going to give a noticeable difference in power. I would be more concerned over the quality of the bits. I would choose Mahle over AA any day
I’ve been running AA 96mm Biral cylinders and KB pistons in a 2316cc engine for several years now but I wouldn’t use AA iron cylinders, 94mm or 96mm. Whatever you use don’t fit head gaskets and adjust the CR with cylinder base shims.
All else being the same ...mostly deck height likely to change.. probably about a 5% drop in CR I made it when i looked... and wouldnt say a massive difference given its a brick . I had a set of stock barrels bored out to fit bigger pistons
Why? Maybe a set of new rings would be just as good and you get to keep your better quality VW parts?
Although, the pistons look OK. The one got hit by valve is dented but OK. I’m a bit concerned about the scoring but it’s not awful. I have ordered both new ring set and a new p and b set. I am hoping to send one back but I just want to be able to create a reliable engine. That’ll get us away on holiday next week Sent from my iPhone using Tapatalk
Seriously, though I'm me, not you obviously, if I was going on holiday next week I'd fit one new head and call it done. Then I'd spend all the time I could trying to figure out why that head got so hot the seat fell out. Could be a problem with the vac servo for example.
I appreciate that input. I’m going with the mindset of whilst it’s on the bench make it good. The bandp set already fitted are AA, some small scoring on the skirt but no play in the pins and are generally well held up. But no worries about changing VW for inferior. As for the head failure, I’ve no idea why it dropped. The heads I’ve got were clearly reworked at some point and pretty certain from 1700 914 heads originally. They’ve been on the van atleast 10 years when the last build was. When it failed I was only cranking it over on the driveway with the fuel tank disconnected just hoping the pump will push out the last of the fuel for 30 seconds. Sent from my iPhone using Tapatalk
That's typical. When its running and loose it literally doesn't have time to fall outs the valve keeps it in place. then when you crank it does. In that case I'd replace both but it's more than likely they will larger combustion chambers which will reduce your compression ratio. Without knowing the cam, the head cc's and the deck height it's not possible to calculate that, but if you could measure the existing and ne head ccs you'd have an idea how much you'll be changing it at least.
Great advice new head is 52cc iirc I’ll measure both tonight before fitting. I’ve now got actual correct 2.0 heads and barrels so it will be more of a correct bus motor Sent from my iPhone using Tapatalk
My original heads I took off turns out they are Porsche 914 1.7 heads that have been bored for 2.0 pistons. They have slightly larger valves and higher compression I’m told Sent from my iPhone using Tapatalk
Unsure on crank size but I can’t see why it wouldn’t it’s a GE case and other than the heads all been 2.0 Sent from my iPhone using Tapatalk
You're probably right. You just never know with these motors after 50 years a case number is just a case number...
Absolutely agree I’ll measure the stroke when I’m checking deck height. I guess it’ll be 71mm for a 2.0? Other than the heads being incorrect but possibly for a performance benefit? The engine seems really decent. All the fuel injection stuff and tins even the thermostat are functioning and correct. Sent from my iPhone using Tapatalk
Why were the cylinder head rings stopped being used? I bought a set as I took a set off? Incase I needed them but not expecting to fit them Sent from my iPhone using Tapatalk
They had a tendency to burn through if a slight leak developed. I "forgot" you have FI - it's more than likely your assumptions are all correct and it's a stock 2l that someone thought those heads would improve. I think for a bus that difference would be minimal if you noticed at all.
