6 rib gearbox question

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Not sure if this helps, but my '71 van runs a 1641 (brand new ssp engine) mated to a standard gearbox and will sit at 60/65 all day. I decided to keep the original box as we take the van abroad and it has to handle some pretty big hills, fully loaded with camping gear. I would get your old gearbox reconditioned and put up with the higher revs(/better airflow to the engine).
 
I would just like to throw this one out there now.

As I said before I was having my 3rib box rebuilt with the 4.57(or 2ltr size) ring and pinion for higher cruising speed.
Got a 1600 with stock cam + 1.25 rockers, twin Weber 34 ICTs, and custom exhaust.

Now I've got the engine back and driven it, I can't say there's a huge issue running a slightly uprated 1600 and 6 rib, especially given that the 6 rib would have a slightly higher final ratio in fourth ,0.89*4.57 vs 0.82*4.57 in my 3 rib.

Will sit at 70 no issue at 3500 rpm, drops to about 60-65 on the hills but was dropping to 55 with the old R&P.
Takes a little longer to get to 70, 1-2 seconds slower max.. Not really noticeable.

I've already got a separate oil cooler, but can't see why it wouldn't be fine on the stock set up. My understanding is that the fan tops out at max CFM not much over 3000 rpm anyway.

So unless I'm getting unusual HP + Torque out of my 1600 then a 6rib is no big issue for one.
 
195/70 R14's all round, about 4% smaller circumference than stock 185/80 R14. Which is 3mph or so at 70.
 
Impressive. Your engine must be putting out some good hp otherwise you would be back to 3rd on motorway inclines. :D
 
Trikky2 said:
Impressive. Your engine must be putting out some good hp otherwise you would be back to 3rd on motorway inclines. :D

With those upgrades I'm sure it's making a similar power to 2 litre
 
K@rlos said:
Trikky2 said:
Impressive. Your engine must be putting out some good hp otherwise you would be back to 3rd on motorway inclines. :D

With those upgrades I'm sure it's making a similar power to 2 litre

Surely if that's the case, the OP with a 1641 + 34 ICT's won't be far off 70-75 HP also?
Might need a better exhaust if still running stock, but that's about all?
I've not done many more changes than the OP, I've only got 1.25:1 rockers because I'm using 33/30mm small valve Mexican EFI heads at the moment so will most likely be loosing power to those on something more stock, 35/32mm or similar.

My concern for the OP would be it could cost somewhere upwards off £400 for a rebuild of his 3rib, but a decent 6rib on eBay wouldnt cost you much more.
 
unknown 6 rib boxes are currently fetching £400 plus, I sold one at the end of last year for £425 plus the cost of a rebuild you are looking at close to £800 for a ready to fit box.
 
I run a 1641 with a 6 rib box with 14" fuchs.

Mine goes very well and very happy with my set up. RPM has dropped, got a remote oil cooler so temp is not a worry.
 
I've been looking for a new gear box for future upgrades on my '72 and have found a 2 litre box with a 1.8 litre nose cone, has anyone heard of this mod before?
 
PICT said:
I've been looking for a new gear box for future upgrades on my '72 and have found a 2 litre box with a 1.8 litre nose cone, has anyone heard of this mod before?

never heard of a 1.8 nose cone? AFAIK 3 rib=1.6L and 6 rib=2L or there abouts?
 
The five rib box fitted to the 1.8 is a nice gearbox but relatively rare since they didn't make them for very long. Ratios are a great compromise between the 1.6 and the 2.0 :)
 
If you're lucky enough to have an 091 I'd fit it, lot less hassle than a beetle box. I'm running an 091 with a 1641 and it's fine, no probs at all. It's the second one I've fitted to my bays and the only thing they have needed is the front mounting changing.
 
Trikky2 said:
The five rib box fitted to the 1.8 is a nice gearbox but relatively rare since they didn't make them for very long. Ratios are a great compromise between the 1.6 and the 2.0 :)
I've got one, but the final RPM's aren't much different then a regular 002 because of the diff used... So I'm going to go to a type 3 box
 

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