Omega Owners Forum
Chat Area => General Car Chat => Topic started by: Thomas-Elite on 30 April 2011, 20:18:47
-
Any mechanical guru's know what six speed box will fit the 3.0 omega? f28? would like to keep my clutch because its a mega one and it cost a fair pop, has only covered a few k miles. dont like the standard box due to being so long. With the map and cams in my car alot of the power is from about 5k up. If i could get someting to keep it in that power band it would be good :) Any input would be grate cheers guys :y
-
If the power's higher up you probably don't want a 6 speed box, certainly not from a modern car ;) ;)
-
If the power's higher up you probably don't want a 6 speed box, certainly not from a modern car ;) ;)
Wouldnt a six speed box have a closer ratio?
-
If the power's higher up you probably don't want a 6 speed box, certainly not from a modern car ;) ;)
Wouldnt a six speed box have a closer ratio?
Some do, some don't - obviously you want one that is.. but if you take the MR2 for example, when Toyota added the 6th gear in 2003, all they did was add a longer gear for cruising and left the rest the same. Then again, it was already a very short-geared box.
None of which helps you in your quest to find a close-ratio 6 speed that'll mate to the Omega :-[
-
Isn't the F28 for FWD ?
-
Isn't the F28 for FWD ?
:-/ yea it is.
-
Isn't the F28 for FWD ?
:-/ yea it is.
if for fwd wont fit a rwd. best bet is a ford mtx75 5 speeder from a seirra cossie
-
Ford box in a GM car !! wash your mouth out Dan. :D ;D ;D
-
Can't you find a BMW gearbox that'll fit?
-
Isn't the F28 for FWD ?
:-/ yea it is.
if for fwd wont fit a rwd. best bet is a ford mtx75 5 speeder from a seirra cossie
MT75. :y
(The MTX75 was the FWD version.)
Still not a close ratio box by any means, although superior to an Omega box in the quality of shift, IMHO. Tediously short first gear, very limited alternative gearkits available and the integral bellhousing would make it hard work to mate to a GM V6 IMHO.
The type 9 has a good selection of gearkits available, and GM pattern bellhousings can be fitted, but I fear it wouldn't be strong enough. :-/
Kevin
-
I'm sure you could get a Tremec T56 with gear ratios you're looking for, and have a bell housing made up to suit - even the 'littlest' one will handle 330lb/ft, and there's always the 'Magnum' if you need >450lb/ft torque cap.
Not cheap, mind, and a little agricultural in it's shift (although a million miles better than the last manual Omega I sat in, which appeared to have the standard Vauxhall Vague-o-Matic gearshift).
-
What about changing the diff? If i got a diff with a shorter ratio wouldnt that close up all the gears? With my engine i do feel that the box is a big hinderance on its power.
-
What about changing the diff? If i got a diff with a shorter ratio wouldnt that close up all the gears? With my engine i do feel that the box is a big hinderance on its power.
It will make the gearing shorter, which may help, but the relationship between each gear and the next is the real problem, and this will be dependant only on the gearbox.
For example, let's say you want to keep the engine in the 5000 - 6500 RPM rev range.
If you change up at 6500 and the engine speed drops to 4500 that is a function of the difference in the two gear ratios. Changing the diff will change the speed at which that upshift is required but the rev drop will be the same, and if that causes a peaky engine to bog down, it always will with those gearbox ratios.
Kevin
-
think it might be worth while talking to a g/box specialist as you might be able to alter the ratios in your box to suit you better,also dont forget tyre size will also have a effect as well.
-
I was thinkging about sticking a 2.0 box on it, but my cars putting out a fair bit of torque and would turn it inside out in a matter of miles. :-[ but im shur that would give me the affect im looking for. Even if for only a short space of time.
-
2.5td manual box has short ratio,s in it? bell housing may need some mods to fit though!!
-
2.5td manual box has short ratio,s in it? bell housing may need some mods to fit though!!
Fair point. Could be something to try. would be strong enough to handle the extra tourque to :)
-
Best thing you can do is to take the gear ratios for various Omega boxes (some are here:)
http://www.omegaowners.com/forum/YaBB.pl?num=1163895469/0#0
.. then plug them into a gear calculator such as this:
http://westfield-world.com/gtc.html
..and see what you're going to end up with.
The important factor for you is going to be the rev drop between gears. So, look at what speed you will hit your shift point in one gear, then find that speed in the next gear and see what engine speed you'll be doing. This is where you'll be after upshifting, so you can decide if you'll still be in the power or if it'll bog down.
Fair point. Could be something to try. would be strong enough to handle the extra tourque to
Will you have any extra torque? Torque is largely proportional to engine capacity so conventional tuning will just move the torque peak to higher RPM and give you more power. Unless you are going forced induction you won't have significantly higher torque.
Kevin
-
I would guess at a 6 speed box off a supra (or a T56) with an Omega auto bell housing plus an adaptor plate between the bell housing and box.
-
I would guess at a 6 speed box off a supra (or a T56) with an Omega auto bell housing plus an adaptor plate between the bell housing and box.
now I am really impressed - I have a Borg-Warner T5 sat in the shed ready to go in the track-day car using just that - an auto bellhousing with a welded-on rear plate.
the options as I see it are :-
use a standard gearbox and have done with it
use a Ford type 9 (5-speed) gearbox as per Kev's post
use a Caterham gearbox which is basically a 6-speed type 9
Toyota 6-speed will need a bespoke bellhousing
T56 will need a bespoke bellhousing and is damn near as heavy as the rest of the car ( I should know, I've just rebuilt one )
The ZF box will need a bespoke bellhousing
.... and any bespoke bellhousing I'd trust would be in the order of £2K
there does also come a point where you'll spend more time changing gear than putting down power in the gear.
My previous track-day Omega had a 2-litre gearbox in it from the moment I took the auto out.
-
T56 will need a bespoke bellhousing and is damn near as heavy as the rest of the car ( I should know, I've just rebuilt one )
;D ;D Granted weight isn't as much of a concern for me, given it'll be sitting behind an iron V8 from 1967, but..
You don't happen to know if the Tremec TKO500/600 is any lighter than the T56, do you?
-
reckon they're about the same.
I suspect that there's a lot of shared architecture ;)
-
I thought that might be the case.. might as well stick the sixth cog on, then :) (Unless I happen across a fantastic deal on a TKO, of course)