Advice on engine gearbox upgrade for a 16"

[bigblue16]

I have a 16" Reimo hi-top camper with a 1.6TD diesel. The gearbox is needing a repair with third going out and second getting a bit snikky and my wife cannot double declutch so its a new car or a repair job (can't bear the thought of losing the syncro). I thought while I am having the gearbox done I might as well think about uprating the drive train so that I can improve the cruise speed (currently 90kph) so the semi-trailers will stop flashing me to get out of the way. I am waaaay out of my depth here so though I would prevail upon the vast knowledge of this forum for some tips.

Intentions - Primarily longevity, simplicity and economy. Improve power and cruising speed to 110kph plus, Remain OEM as far as possible and not go overboard with power increase so as not overstrain the existing mechanical systems.

Gearbox ideas:
Gearbox and front diff to Aidan Talbot for overhaul. Replace 3rd and 4th with longer, stronger gears (poss 0.77 4th). 4.86 final drive. Fit oil plates
I already have an oil cooler fitted

Engine ideas:
Convert to mTDi 1.9l so that I can use all the bits from my current JX (1z engine avaulable). Upraded injectors, charge cooler etc with target around 120 HP

Other stuff
Tighten up the gear linkage and replace any worn bushings.
Check the prop shaft and possibly repack the U-joints and replace the bushings.
Check the viscous coupling,

BY the time I finish all this I will need to strip the body and repaint. But seriously does anyone have any opinions on the mechanical premise here. Will the 4.86 final drive mate well with the 1.9l engine choice and the 16" syncro ? Any tips will be well received thanks

[Mudlark]

Looky Here : http://www.haywood-sullivan.com/vanagon ... y_tdi.html

[John Potter]

Hope you’ve got a nice deep bag of money, that lot won’t be cheap.

All good stuff though....

[silverbullet]

I think Aidan has closed his diary now for his well-earned break, but no harm in asking. The question is - who's going to pick up the slack during his sabbatical?

[bigblue16]

I think Aidan has closed his diary now for his well-earned break, but no harm in asking. The question is - who's going to pick up the slack during his sabbatical?

Hi Silverbullet - way ahead of you there - I already have the booking but was advised to let the experts here have a gander at my proposals to see if anyone could come up with good reasoning against the numbers. I have been lurking around this and many other forums and have learned a lot here, mainly to keep quiet and listen to my betters.

So if you think there is a problem...i.e. is 4.86 too low for a final drive? Originally a 6.16 and it was slooow, but I don't want to overload the transmission and axle/CV joints etc read some horror stories about that which is why I dont want a lift kit. Anyway if I did that I would have to build in elecric stairs for the wife.

[lloydy]

mines got a 6.16 60mph tops if i want the engine to last the journey!
But i can live with that, don't really want to spend 5-6k on a TDI and gearbox. Personally i'd rather accept it's an old van and enjoy the journey.
An AAZ would be the only thing i'd consider (unless of course i win the lottery then it will be a V6 TDI for 12k by bernd jager)

[spannermonkey]

Bigblue16,

I'm in a similar situation with my 16 and planning for this over the next 18months. Absolutely love my syncro, but want to make some improvements over time; much as I like the reliability of my little 1.6TD lump, it's lack of power/gearing can be tiresome on a long drive. I'm of the mind like you, if your gearbox is coming out, you might as well make the ratio changes and powerplant swap then. First off, have you seen this Gear Ratio calculator?

http://www.syncro.org/Files/syncrotirea ... tiosdd.xls

It takes a bit of work on google to fill in the missing gaps of your tyre sizes and current setup of ring and pinion for gearbox and front diff, it's also been designed around the wasserboxer engine, but still gives you the right idea. For a TDi conversion I imagine you would want to keep the revs in 4th as low as possible (around the 3000-3500rpm mark) to preserve economy. I like your design brief;

Primarily longevity, simplicity and economy. Improve power and cruising speed to 110kph plus, Remain OEM as far as possible and not go overboard with power increase so as not overstrain the existing mechanical systems

The only difference for me is that I want to preserve my 6.17 R/P ratio in the gearbox and front diff (original 16'' 1.6TD spec afaik) to maintain the stock G gearing (I like the way it drives off road)- I'm happy to lose some top end speed so long as I can make some improvement over what I've got! I think this is achievable in principle with a 0.7 4th gear. I also think to change your ring and pinion gears for gearbox and front diff could up the overall cost considerably, but Aidan can no doubt advise. What ratios have others used?

I too am thinking of TDI, still weighing up the pro and cons of m- or e-. Poss. AAZ.

As John Potter says though, I hope you have a healthy budget for all this!

Steph

[bigblue16]

mines got a 6.16 60mph tops if i want the engine to last the journey!
But i can live with that, don't really want to spend 5-6k on a TDI and gearbox. Personally i'd rather accept it's an old van and enjoy the journey.
An AAZ would be the only thing i'd consider (unless of course i win the lottery then it will be a V6 TDI for 12k by bernd jager)

Apreciate the logic but after living with the bus for over a year and having driven an uprated syncro I have realised that I will enjoy it more with greater capability.

I put about 15-20,000km or more a year on my campers ( having 6 months a year off helps) and with having to do the gearbox anyway I have figured that with the increased economy I will get most of the cost back in a couple of years. I live on the continent, and the semi-trailers here tailgate you if you drop below 100kph and flash til you get out of the way so a slight improvement in cruise to 110kph will be very welcome. Besides my wife has a hard time keeping it down to 90kph (she can't seem to hear the screaming, either from me or the diesel) and I am not going to try to fight that.

As for Berndt, a very interesting bloke. I spent a couple of weekends down at his place and I like a bloke who has been out and done it. He and his wife have lots of good stories and he and his mechanics do excellent work and will work to a fixed quote. But before you go down there you better know exactly what you want 'cos he is not waiting around for you to make up your mind.

[syncropaddy]

Be careful what you do with the final drive ratio if you change 3rd and 4th. You might make it undriveable. I have a gear ratio/ speed thing if you want to work stuff out but if you can get 100kmh @ 3000 rpm then that is good. I also think that 120 BHP is a little optimistic. A 130 TDi engine out of a Passat does NOT give 130bhp when fitted to a Syncro so be carefull with the engine. A good AAZ installation is as good as a 1Z and revs better.

[bigblue16]

Be careful what you do with the final drive ratio if you change 3rd and 4th. You might make it undriveable. I have a gear ratio/ speed thing if you want to work stuff out but if you can get 100kmh @ 3000 rpm then that is good. I also think that 120 BHP is a little optimistic. A 130 TDi engine out of a Passat does NOT give 130bhp when fitted to a Syncro so be carefull with the engine. A good AAZ installation is as good as a 1Z and revs better.

Thanks for that syncropaddy - this is ths type of information I am looking for. As I say I am not any kind of an expert here and need some advice peferably from someone who has done this conversion or something like it.

I would really appreciate your gear ratio/speed thing so I can do my sums. Interesting note about the AAZ, it was originally my first choice but I was put off by the stories of crank pulley failure. What do you mean by "revs better"? wider rev range? Do you have any figures? The 1Z was offered to me as when coupled with an uprated fuel pump and injectors it would easily provide the power I needed. Having said that I am not after a stoplight screamer just a reasonable amount to enable a 110kph cruise with a bit in reserve and anything near 100HP is an improvement over my JX .

Once again thanks for the information. I look forward to having a play with the gear ratios.

cheers

[Russel]

An AAZ is nothing like a TDI and never will or can be.
Wot you are looking for in an engine is torque.
Ideal rev range for TDI at cruising speed [ 100 to 120 km/h] is 3000 to 3200 rpm. No more. You can go less {not much though} but this will depend on the weight of your van and drag on it { high top MT tires etc}
Keeping your stock final drive is a good thing but this will depend if you can achieve the correct rev range with your combination of gears and tire size.
An AAZ will not give you a better top end over a JX. It will give you a bit more torque and make your drive less hassle.
Russel

[syncropaddy]

Be careful what you do with the final drive ratio if you change 3rd and 4th. You might make it undriveable. I have a gear ratio/ speed thing if you want to work stuff out but if you can get 100kmh @ 3000 rpm then that is good. I also think that 120 BHP is a little optimistic. A 130 TDi engine out of a Passat does NOT give 130bhp when fitted to a Syncro so be carefull with the engine. A good AAZ installation is as good as a 1Z and revs better.

Thanks for that syncropaddy - this is ths type of information I am looking for. As I say I am not any kind of an expert here and need some advice peferably from someone who has done this conversion or something like it.

I would really appreciate your gear ratio/speed thing so I can do my sums. Interesting note about the AAZ, it was originally my first choice but I was put off by the stories of crank pulley failure. What do you mean by "revs better"? wider rev range? Do you have any figures? The 1Z was offered to me as when coupled with an uprated fuel pump and injectors it would easily provide the power I needed. Having said that I am not after a stoplight screamer just a reasonable amount to enable a 110kph cruise with a bit in reserve and anything near 100HP is an improvement over my JX .cheers

Yup the AAZ revs to 4600 as far as I know which is about 200 more than a JX does. Yup there are pulley issues on some AAZ engines but Mr Baxter sells stuff to sort that out and there is good info on Brickwerks site.
As regards the gear ratios I have standard ratios but a final drive which is almost 1.00 taller than standard and there are issues when cruising on motorways when a nice long hill appears so I would follow the 3rd and 4th gear route.

[silverbullet]

FWIW, any T3 is at it's best when cruising at 60-65 tops. After that the - for want of a better word - aerodynamics cone into play and fuel consumption rises alarmingly, whatever the gearing.
I simply went from 185/80/14 on our DG syncro (4.86 diffs) up to 215/75/15 and whilst it performs great offroad in G, top speed went from a comfy 65 to more like 55 and breaking a sweat. A little bit of clutch slip is now needed to pull away in 1st, even on the level and it's nothing like as sprightly on the road. More like plain slow.

[jed the spread]

I think Russel will agree an AAZ is a great replacement engine for a JX. It will give you much more and without having to modify your standard gearbox (oil plates though if it was me for the extra few quid) if you run 215/75/15 wheels/tyres. I love mine

Now then...

I am not going to give you aload of flannel here relaying what I have read on the internet as my actual experience and knowledge, the thing is I like to have ago and learn some stuff while actually doing it with the help of people mainly off here.

About a year ago I was in your position, only a buggered engine and shagged gearbox on my Camper. As it happened back then I had a good few grand saved as I had a really good run of work for a while and took it to Russel@Synconutz just for some advice really but with the insight to let him get on with it really. I bought my van quite cheaply and had about £6000 left after the bit of bodywork that needed doing was done, next thought was what engine. My situation was I needed an engine of some kind and a gear box rebuild and I also had a f*cked VC.

I settled on an AAZ conversion with a gearbox rebuild with the extra oil plates (good gearing for an AAZ if you have wheels with 215/75/15 tires). I could have gone MTDI (extra £2500 maybe), Got Aiden to put the longer 3rd and 4th (extra £500-£600).

For under £4000 I got an engine conversion with enough power and does 30mpg, new turbo, oil cooler, gearbox rebuild, new VC, and loads of other stuff I cant think of that makes the van run better than VW made it and a perfect 4wd running system. With the rest of the money I went off and enjoyed the van around UK, Wales, France, Belgium, Holland, Germany, Spain, etc...

The only time I think I would prefer an MTDI is when I am with people who have them and thats only on twisty turny country roads, off roading in G gear is not quite as good but miles better than any of the petrols I have driven. On motorway driving apart from an Mtdi will do about 8 better than me on MPG (with the one I am used to driving with and the owner doest bullsh*t like a good un) and is abit better up the short steep hills. I love an AAZ as they run miles smoother than a MTDI and sound really nice, a great replacement for a 1.6td. Saying that now I am developing my mechanical knowledge I am aiming on getting an MTDI when I feel like it but upping the gears with big wheels and with what I have as a set up now It will only cost £1500 if I do all the work (apart from fiddleing with the pump) myself.


jed

[bigblue16]

An AAZ is nothing like a TDI and never will or can be.
Wot you are looking for in an engine is torque.
Ideal rev range for TDI at cruising speed [ 100 to 120 km/h] is 3000 to 3200 rpm. No more. You can go less {not much though} but this will depend on the weight of your van and drag on it { high top MT tires etc}
Keeping your stock final drive is a good thing but this will depend if you can achieve the correct rev range with your combination of gears and tire size.
An AAZ will not give you a better top end over a JX. It will give you a bit more torque and make your drive less hassle.
Russel

Russel, thanks for the input. I appreciate the time that traders on this forum put in for little return so thanks for whatever gems you can toss my way.
As mentioned the bus is a hi-top with stock standard tyres 1.6TD and packed with only basic camping gear. However I may load it up a bit when I go further afield later. Regards the final drive: originally it was 6.16 and I was looking at possibly a 4.86 together with the 0.7 4th gear. The engine offered is a 1z mTDi with uprated fuel pump and injectors charge cooler etc which the builders say will get 120 HP. Would you consider this engine and gearbox to be a good combination on a 16" syncro with standard tyres, or is it a bit of a reach and is there a possibility I will run out of revs or torque where I want to cruise - about 110kph? If so would I be better off with a final drive in the order of 5.43? Any other suggestions?
Cheers