How bad are BW35's.....really?

Oldskoolrob

Active Member
I have a quandry. I'm gathering stuff to throw into my Mk2 Cortina. It's easier/cheaper to go with a BW35/65 as they bolt straight up to the engine. But I could get an adaptor bellhousing and use a Ford C4 or TH400. The bellhousings aren't cheap, and the car is a cruiser, so would the BW be 'adequate' wouldn't it...they're not that bad of a box really....are they? I mean the one in my P6 shifts ok, but the clutches must be worn as she shudders if you get 'sprirted' with it....and you can't park on a hill or it leaks....but it's not ever been rebuilt. A rebuilt one should be .....ok?
 
Just been down that road with my BW35. The gearbox man used my original shell and replaced everything inside with updated parts for an Auzzie Ford Falcon box. So far Im very happy with the result after 6 weeks.
 
I am inclined to say that the BW35 is as good as the person that rebuilds them, and as good (or bad) as the person that drives them. My BW35 (rebuilt as an M51) has been working perfectly behind my Rover's 4.6 litre V8 engine since 2009 with 183,400 miles (295,274km) covered in that time.

Rob, the Ford C4 or the Turbo 400 are both considerably stronger than a regular BW35, but it all depends upon what you want from it? If as you say your car is a cruiser, then in my mind the BW35 is more than adequate. The greatest load imposed upon any transmission (drive train) is when accelerating from a static position. The faster you wish to accelerate, the greater the load imposed.

Ron.
 
If you go for a BW66 then that stayed behind the Jag XK 4.2 engine without too many problems. If you use the BW66 converter and gearbox that will bolt straight in with the RV8 bellhousing and driveplate. I'd do that in preference to the BW35, but if it is a just a cruiser then it should be adequate.
 
PS Remember that the BW35 is a lot wider than the BW65/66 and if your Mk2 is a manual car then the tunnel probably won't be wide enough for the 35, whereas the 65/66 might just squeeze in, avoiding the need to fabricate a new tunnel.
 
PS Remember that the BW35 is a lot wider than the BW65/66 and if your Mk2 is a manual car then the tunnel probably won't be wide enough for the 35, whereas the 65/66 might just squeeze in, avoiding the need to fabricate a new tunnel.
Thanks for that Harvey, I didn't know that. I'm contacting a bloke about a BW66, but he's 4000km away....Just have to see if I can find one closer. My engine is only 1600km away lol. PS Car is an auto with a 4cyl BW35 in place at the moment.
 
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Car is an auto with a 4cyl BW35 in place at the moment.

That does make the conversion a lot easier, but that BW35 won't be the same spec as the one that goes behind the RV8, but could easily be uprated. If the RV8 would fit on to the front of that box without fouling the bulkhead that I think I'd go that way, it will save having to make a propshaft and recalibrate the speedo/make a cable.
 
Hi, A much more straight forward conversion gearbox wise, the next thing is getting the engine to fit in the 'bay especially round the steering box.

Colin
 
Yeah It all gets a bit squishy there... I guess once I have the engine and a box physically in my possession I can start looking at solutions. Worst case will have to be a rack and pinion conversion I guess.....will see....
 
That does make the conversion a lot easier, but that BW35 won't be the same spec as the one that goes behind the RV8, but could easily be uprated. If the RV8 would fit on to the front of that box without fouling the bulkhead that I think I'd go that way, it will save having to make a propshaft and recalibrate the speedo/make a cable.
That's an idea I never even thought of.....I'll have to contact a local box builder to see what's possible I guess.
 
I'll have to contact a local box builder to see what's possible I guess.

Uprate the clutch packs from what is probably 3, to five, which may just be a case of different pressure plates, if not bigger drums, fit the largest possible front servo, and replace all clutches and bands doing all you would during a normal rebuild.
 
Uprate the clutch packs from what is probably 3, to five, which may just be a case of different pressure plates, if not bigger drums, fit the largest possible front servo, and replace all clutches and bands doing all you would during a normal rebuild.
Looks like I've bought the '66 on the other side of the country. Just have to organise getting it here.....
 
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