Need a gearbox, but what could I use?

mike332 · Post by **mike332** » Wed Jul 18, 2007 3:44 pm

Right then, I'm looking for a suitable gearbox. The one's we usually use are the bedford cf zf gearbox with a 3rd gear ratio of 1.6something. These are proving hard to find (well to me at least)

I need a good strong box, to take around 210 bhp for my stockcar, it will be fitted to a 3.5 rv8. Any ideas? I want something that's quite easy to find and cheap too!

stevieturbo · Post by **stevieturbo** » Wed Jul 18, 2007 5:37 pm

Obvious choice would be the normal LT77 that usually comes on a Rover V8.

Or whatever is fitted to those Sherpa vans, although the stick is in a totally different location with those.

ChrisJC · Post by **ChrisJC** » Wed Jul 18, 2007 8:32 pm

Or an R380 if you can get a 2WD one.

Chris.

mike332 · Post by **mike332** » Wed Jul 18, 2007 9:10 pm

Anybody know the ratio of 3rd gear in an lt77?

Post by **katanaman** » Wed Jul 18, 2007 10:18 pm

SD1 box is 1st 3.21 2nd 2.08 3rd 1.396 4th 1 5th 0,792
Sherpa 1st 3.985 2nd 2.519 3rd 1.507 4th 1 5th 0.831

mike332 · Post by **mike332** » Wed Jul 18, 2007 10:31 pm

katanaman wrote:SD1 box is 1st 3.21 2nd 2.08 3rd 1.396 4th 1 5th 0,792
Sherpa 1st 3.985 2nd 2.519 3rd 1.507 4th 1 5th 0.831

Thanks, sounds like the sherpa is closer to what I need then, still quite a bit over geared though

Post by **katanaman** » Wed Jul 18, 2007 10:36 pm

then change your diff ratio if you can. You also have to remember where a V8 makes its power as it isn't the same as a pinto

mike332 · Post by **mike332** » Wed Jul 18, 2007 10:44 pm

katanaman wrote:then change your diff ratio if you can. You also have to remember where a V8 makes its power as it isn't the same as a pinto

True, don't think we've got much choice on diff ratio, we are using volvo 240 and 740 axles, we chop 240 n/s axle tube off and weld it on the 740, that offsets the rear axle and diff, which gives us more inside weight on the rear, helping to get more bite when booting it out of the corner. Because we only turn left, it can help a lot.

Paul B · Post by **Paul B** » Thu Jul 19, 2007 3:45 pm

mike332 wrote:
katanaman wrote:then change your diff ratio if you can. You also have to remember where a V8 makes its power as it isn't the same as a pinto
True, don't think we've got much choice on diff ratio, we are using volvo 240 and 740 axles, we chop 240 n/s axle tube off and weld it on the 740, that offsets the rear axle and diff, which gives us more inside weight on the rear, helping to get more bite when booting it out of the corner. Because we only turn left, it can help a lot.

I've got a Sherpa axle in my Morris, with a 3.9:1 Westminster diff in, but I want something with a ratio closer to 3.2, and about 8" narrower, so I can fit wider shorter wheels. Any idea which Volvo axle would be my best bet? Any with an LSD?

mike332 · Post by **mike332** » Thu Jul 19, 2007 4:01 pm

Not sure about lsd, I don't think any of the volvo axles had them in as standard. The 240 axle is 59 inches face to face, and the 740 is wider by about 3 or 4 inches I think, either that or the 740 is 59 inches and the 240 is narrower. Another option we sometimes use is a transit mk1/2 twin wheel axle, these are quite a bit narrower, but I think the highest ratio in them is around 4.1, the volvo I think is closer to about 3.8 or 3.9

mike332 · Post by **mike332** » Thu Jul 19, 2007 9:52 pm

Found this on fleabay. Is this the same box as the lt77, and if so which ratios should it have? Are they any good for what I need?

5000SE · Post by **5000SE** » Thu Jul 19, 2007 10:02 pm

mike332 wrote:Found this on fleabay. Is this the same box as the lt77, and if so which ratios should it have? Are they any good for what I need?

Fairly sure it's the same LT77 as the SD1, with ratios the same (SD1 box is 1st 3.21 2nd 2.08 3rd 1.396 4th 1 5th 0,792 ).

mike332 · Post by **mike332** » Fri Jul 20, 2007 8:46 am

Thought it might be........ cheers

Paul B · Post by **Paul B** » Fri Jul 20, 2007 4:19 pm

mike332 wrote:Not sure about lsd, I don't think any of the volvo axles had them in as standard. The 240 axle is 59 inches face to face, and the 740 is wider by about 3 or 4 inches I think, either that or the 740 is 59 inches and the 240 is narrower. Another option we sometimes use is a transit mk1/2 twin wheel axle, these are quite a bit narrower, but I think the highest ratio in them is around 4.1, the volvo I think is closer to about 3.8 or 3.9

3.8, 3.9 would be same as my current axle, 4000rpm at 80mph

Back to the drawing board methinks.

topcatcustom · Post by **topcatcustom** » Tue Oct 28, 2008 10:36 pm

katanaman wrote:SD1 box is 1st 3.21 2nd 2.08 3rd 1.396 4th 1 5th 0,792
Sherpa 1st 3.985 2nd 2.519 3rd 1.507 4th 1 5th 0.831

Sorry to bring this up again all, but just wanted to check that this is true of all SD1 'boxes, my serial number is 28A0011412D and I think is a Vitesse lump!