Has anyone fitted a 3.0 12v box to a 3.2 GTA gearbox without to many modifications.
Geraint
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Has anyone fitted a 3.0 12v box to a 3.2 GTA gearbox without to many modifications.
Geraint
Dont know anybody Geraint but shouldn't hold too many problems, just clutch parts??
Should be fine Geraint.
As John says, just need to match clutch type to your 5 speed box (push / pull + bearing) - 24v clutch is bigger diameter than 12v but box inputs are the same. I went the other way ok and changed 5 speed to 6 speed on 24v.
Are you keeping the GTA flywheel?
Neil AKA Turbo Nutter is doing the same but he swapped to light flywheel and twin plate clutch and re balanced
Haven't done it to my 12V 3.0 Alfa, but did do it to my 24V 3.0 Alfa. I used the 24V flywheel and the GTA clutch assembly.
Thanks one and all
Your comments suggest that maybe the best solution would be 12v gearbox 24v flywheel and remain with the GTA clutch assembly.
So, I need to ask, why are you doing this?? Is the GTA gearbox a 6speed?? Are you replacing a gearbox in your car (Stratos kit)? Does the cable shift mechanism scare you?? Fear not, there are kits out there being developed and should be markets soon.
It's because:Quote:
Originally Posted by tipo158
Geraint's car is already up and running with a 12v and 5 speed
So that saves making new engine mounts and a new gear shift
The 6 speed has a weakness (only in extreme cases)
I have a GTA which has only done 7,000 miles therefore I am now in the process of replacing the engine, and have discussed the 6 speed selection issues with other members at the NEC during the weekend. I will need to fabricate new engine mounts, and thought that I could use my existing Hawk selector shafts. I believe that selecting sixth can be a hit or mis as the reverse position is fairly close. Before I committe myself to replacing the box I need to ensure that this is the correct way forawrd.Quote:
Originally Posted by ProtoTipo
Hitting sixth instead of reverse isnt a problem if you fit some sort of detent/lockout for reverse, just that most people can't be arsed making something to fit on their gearlever.
The only thing I needed to modify for motor mounts was that I needed a longer piece of threaded stock for the mount for the gearbox. It just seems to be a lot of work. My kit is a Litton.
John,Quote:
Originally Posted by strat6v
I had a solution in mind for that, but as I've reverted to 4 pots, that's as far as it went.
I can see the sense in Geraint retaining the 5 speed. Then all it needs is the oil filter/foot mount mod. 'Same as your's.
It's less work to do that way. Leave all the mounts as they are, leave the gear shift as it is.
Facility is there on old alfa gearboxes, albeit slightly different.
Getting 6th on a six speed is NOT a problem Ger - no where near reverse, don't let that put you off if thats your only concern.
The gate across to reverse is much further across and not a problem. Unless you are in the habit of going to 6th from anything other than 5th you'll only ever be going straight back. I've never missed reverse and got 6th instead ever either.....
maybe its testiment to JH's linkage design or the set up I've done but not ever had a problem with it. On saying that though I'd not worry that much about going back to a 5 speed if I had to. May be straightforward for you as Chris says.
What I think may need some thought is swapping flywheels, you could be lucky and just make it a bit lumpier. But could also ruin your mint smooth engine without a rebalance (or worse). If you are set on that though, If I remember right I think the 156 2.5 was the lightest.
I don't think mine is particularly light but still picks up and revs like a bike.
...however I wouldn't recommend dropping a paddle clutch at 7000 RPM on a 6 speed with hot sticky tyres...........:) 2nd box (strengthend) now in service and going well ..but the ratio benefits outweigh the drawbacks...
I've never driven an Alfa engined car, but I mentioned to Geraint (at the NEC) that people had about the top gear on a 6 speed being great for Motorway use. The thing is, Geraint said (if I remember right?) that he'll use the car for sprints and stuff, so that's another reason for sticking with the 5 speed?Quote:
Originally Posted by Sando
Useful comments from Rob's experience with 6 speed, I could be compromising the smoothness of the existing setup, and creating problems with adapting to a 5 speed. Are all these cabled selectors, and would someone have photos available showing the linkages. John could you supply the selector parts? Rob would you have photos showing how you've strengthend the box?
All thats required is a new rear section of linkage, your frontbit with lever and the centre bits all stay the same. I can supply the rear linkage bits if you want, will have to work out a price.
I've got a photo here of John's linkage Geraint. I can email it. 'Won't post it on this forum, unless John doesn't mind.Quote:
Originally Posted by strat6v
If you could supply the linkages and work out a price for me that would be great John some photos would be useful as well.
I put a GTA box on my 12V motor. Gear linkage took a bit of work (mostly by CJ with minor tweaks by me). After some tinkering, the reverse lockout worked a treat - gearchanges were lovely. My motivation for the swap was changing an old (but OK) 5 speed for a relatively new GTA box with Q2 as at the time, I had intended keeping the car. If you happened across a NOS 24V 164 box it would be an excellent option for your situtation I'd think.
Did you have to modify the GTA box to fit the 12v. Did you use the GTA flywheel and clutch assembly?
You really need to stick with the flywheel from YOUR Gta. Whole bottom end is setup with that and the harmoic balancer at the other end. Change things for differently balanced items isnt the best idea, you could send your bottom end to vibration free?
No mods to the box as such - I retained the flywhel and clutch from the 12V gearbox and used a combination of 12V push and 24V pull clutch parts to relocate the slave to somewhere convenient. As far as ratios go, the 6 speed covers basically the same span as the 5, so would be better for sprinting I'd think. Or at least, I ended up with the same mph/1000 in 6th that I'd had in 5th on the previous box. Does of course depend on which final drive ratios you had.
As John says - retain the flywheel and clutch that belongs to the engine then just use the required bits to make the clutch actuator work - they are all pretty interchangeable. Worst-case and you might have to tweak the operating arm and/or slave cylinder locating bracket. None of those things is hard.
Going back to this thread, not sure what the outcome was for Geraint, but I am using a lightened 12v flywheel on my 24v engine, with a 12v gearbox (and push-type clutch).
If I put on a 24v gearbox, what are my options regarding the clutch - assuming I will be keeping my flywheel, as it's the only one I have?
Does the 24v clutch fit onto the 12v flywheel, or does it have larger mounting bolt pcd?
With the 24v gearbox having pull-type clutch operation, if I fit a 24v clutch, does the 12v slave cylinder fit onto the 24v gearbox, using the mounting bracket for either box?
Or should I stick to push-type operation and put the 12v clutch operating arms, linkages and slave cylinder onto the 24v box, and use a 12v clutch plate too?
Will put an uprated clutch in there if I can find a suitable one, whether 12v or 24v fitting.
Cheers,
John
As Chris has said above John, you'll need to use 12v clutch (you are right different clutch size and bold pattern to 12v). And swap actuating arms over to keep push type slave using mix of bits from both boxes. Six speed still works with 12v clutch and flywheel. Mine is same but I use Helix paddle clutch.
Cheers Rob, that all makes sense.
Does that paddle clutch work with standard flywheel and release bearing, or does that change as well?
And dare I ask what sort of price is attached to the paddle clutch, is it a standard part from Helix?
J.R.
Yep std flywheel fine john, not sure about std release bearing, but they do one with the plate and cover or individual parts . Both 12 and 24v listed ...... not cheap unfortunately probably near £4-500 now for al the bits.Quote:
Originally Posted by rutthenut
If youve coped ok with a standard clutch up to now I'd continue that way. Maybe just an uprated organic plate ?