From another thread: New Gearbox now fitted, so I thought i'd update this thread with the impact it has made. New box was built by Bears and is based on an 002 box with same gears as standard, except 4.57 ring & pinion (apparently it's only the final drive that alters the overall gearing). Tyres are 185/65 R15 88T. Engine is 2110cc type 1. New gearbox: 70mph @ 3,200 rpm. Doing 105 Miles on motorway & a roads at 70mph produces oil temp of 80c Old gearbox: 70mph @ 4,000rpm. Doing the same 105 mile journey as above produced oil temp of 90-95c Summary: Very pleased with gearbox so far. I would thoroughly recommend Bears. I'm glad I went this route rather than fitting a 2nd hand 009 gearbox or buying a freeway flyer from VW heritage. New box feels nice and tight. A gearbox with 4.57 final drive is better suited for a 2110cc engine than a 1600 box. Engine temperature has gone down as engine not working so hard for same driving speed - some thought it would run hotter as fan wouldn't turn as fast. Fuel economy has improved by approx 2.5l of fuel per 100miles. I've not done much driving around 'town' yet. I hope this info will be helpful for people with large engines who are considering a new gearbox. I obviously don't drive the van for fuel efficiency but I'm happy it is slightly more efficient now. If any of you need to justify the cost of a new gearbox to yourselves or your other halves then i roughly calculate that it will pay for itself in about 28,000 miles! Cheers for all the input people gave in the past. Feel free to message me with any questions based on my experience. Thanks Paul
@paulcalf are you measuring cylinder head temperature? The drop in oil temperature at lower revs is because the bearing surface speed and oil shear has reduced but the fan speed has also reduced so I’d expect to see an increase in head temp with less cooling. Your van weighs the same, it has the same wind resistance and the engine has to produce the same power to maintain the same speed regardless of the engine capacity or revs. At the same speed a 2110cc engine is working just as hard as a 1600cc it’s just not so close to its maximum power.
The fan speed is directly proportional to engine speed. 1:1 for a type 4 and whatever the crank to fan pulley ratio is on a type 1. Do you mean the speed at which the fan produces most air flow? Bigger capacity engines can get you to a desired speed at lower revs because there is a direct relationship between capacity and torque and a big capacity engine will generally (depending on the cam profile) produce maximum torque at lower revs, but the engine is working just as hard and producing the same amount of heat. It’s actually working harder to accelerate the same mass quicker, but it’s over a shorter period of time.
No I'm not measuring cylinder head temp. Just passing on what I've experienced, without understanding things! Oil temp is lower No idea on what my cylinder head temperatures have ever been on any set up. Pleased to have extra fins on my current cylinder heads, now that I've read your post!
Oil temps of 80c are way to low .....burning fuel creates water and the oil needs to reach at least 100c occasionally to burn of the water otherwise it reacts and creates acids which damages bearings ....
Don't worry I let my oil get hotter than that. That was just the temperature on two identical journeys. No white gunky emulsion crap in my oil
It's still very low ...mine sees 90-95 and max 115 c , are you running a deep sump or remote oil cooler ?
I'm running a remote oil cooler, but don't use it a lot of the time. Don't get hung up on the 80c reading or the 90-95, taken years ago. They just happened to be the readings on two journeys where the difference was a changed gearbox. I've done about 12k on that set up now and oil temperatures are where you want them
Thanks for all the info folks. Still haven't decided. @paulcalf thanks for the email with your own experiences. 1776cc sounds more than enough. Dropped my case to jon white in vwspares in kildare on friday. He's bringing it to dave in the north. Jon reckons the end float in my case is borderline so lets see what happens there first before I decide where to go after that
so my engine case is shot! there was actually corrosion on the underside underneath all the gunk. So in a way that leaves me with a blank canvas size wise but at the same time I'm not made of money so I need to have a think about it. and maybe a little cry
Do it right and do it once Consider: How often you will use the bus? How many miles per year? How long do you intend to keep the bus? How deep your pockets are? Can you 'justify' spending LOADS as the cost per year will work out as very little? Various options, all dictated by money: I got an old case rebuilt with all new parts into a 2110cc, it leaks oil, 20mpg tops but I love driving it and it has plenty of power! Hindsight I should have got a new case and fitted velocity stacks under the air filters. A mate bought a 2nd hand John Maher 1776cc engine, going well so far My off the shelf experience was not a good one - I would really try and steer clear of this, but others have had more luck Many are going Subaru, they have loads of power and some say/claim 35mpg!
Funny you should mention subaru because I've been look at that option for the last half hour. If I can pick up an engine reasonably cheap, the conversion would probably still work out cheaper than an aircooled engine? I'd like to use it a lot and plan to hold on to it for a long time.
I think Fellows costs are comparable to getting an aircooled specialist to build you a top motor Subaru engines can be picked up cheap- you may be quids in, if you can do the conversion yourself If you can do a scooby conversion yourself, then you could probably build yourself a decent air cooled engine though?
