Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: Sir Sideways on 06 January 2007, 12:26:23

Title: 2.5 G/box on 3.0?
Post by: Sir Sideways on 06 January 2007, 12:26:23

After much searchin ive not been able to find a 3.0 donor car so im lookin towards a 2.5. Would a 2.5 manual gearbox be strong enough for the 3.0?

Many Thanks

Jim

Title: Re: 2.5 G/box on 3.0?
Post by: Markjay on 06 January 2007, 12:29:54

Quote

After much searchin ive not been able to find a 3.0 donor car so im lookin towards a 2.5. Would a 2.5 manual gearbox be strong enough for the 3.0?

Many Thanks

Jim

I don't know the answer for fact, but from my experience with other cars the difference in manual gearboxes between engine sizes on the same car is usually different gear ratios rather than actual strength - it's the clutch that needs to be up to the job in terms of meeting the power and torque, and on large engine cars the clutch will have larger diameter i.e. larger surface area etc.

Title: Re: 2.5 G/box on 3.0?
Post by: Markjay on 06 January 2007, 12:34:37

Incidentally, the manual gearbox listed for 2.0 and 2.5 is R25, and for the 3.0 it is R28. As said before, I would imagine it's down to different gear ratios - i.e. your car will improve on the 0-60 run but will have lower top speed, plus you'll run out of revs and need to change-up sooner than before.

Title: Re: 2.5 G/box on 3.0?
Post by: Marks DTM Calib on 06 January 2007, 12:52:33

Bigger bearings etc in the R28...much stronger box so, no the R25 would not last so long....

Title: Re: 2.5 G/box on 3.0?
Post by: TheBoy on 06 January 2007, 13:37:46

Probably best place to look for 3.0l manual box is from a written off ex-plod...

Title: Re: 2.5 G/box on 3.0?
Post by: Sir Sideways on 06 January 2007, 15:09:26

Its just finding one, thats the problem im having. searched through a cpl of salvage yards too for a write off but still nothing. maybe 1 will turn up when it snows  ;D ;D

Title: Re: 2.5 G/box on 3.0?
Post by: Marks DTM Calib on 06 January 2007, 16:34:36

What about this one:

http://cgi.ebay.co.uk/VAUXHALL-OMEGA-ELITE-5-SPEED-MANUAL-GEARBOX-PEDALS_W0QQitemZ170067631683QQihZ007QQcategoryZ10404QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Ask him what it came from.

Title: Re: 2.5 G/box on 3.0?
Post by: Sir Sideways on 06 January 2007, 18:29:00

Thanks for the link Mark, ive asked too.

Jim

Title: Re: 2.5 G/box on 3.0?
Post by: tunnie on 06 January 2007, 18:40:04

Quote

Its just finding one, thats the problem im having. searched through a cpl of salvage yards too for a write off but still nothing. maybe 1 will turn up when it snows  ;D ;D

Jim,

How about going to an ex-police auction. The one up here in Witney is supposed to be good, and they go cheap.

Buy one (fully working) and swap it over... and sell the plod as an Auto. Be cheaper... :y

Title: Re: 2.5 G/box on 3.0?
Post by: Markjay on 06 January 2007, 18:41:02

Quote

Bigger bearings etc in the R28...much stronger box so, no the R25 would not last so long....

So I was right!  :y

Not about the gearbox - I got that wrong - I was right when I said I don't actually know the answer...  :(