[active]

Hello guys,

Has anyone tried to fit any gerabox to alfa romeo 33? For example subaru impreza ant etc. I'm intresting in awd gearbox fittings, because the standart alfa 33 4x4 gearbox looks very "sad" with supercharged engine. All comments and ideas are welcome.

 

[blacknight]

hey mate, thats a good question i was thinkin bout it the other day, i have a 1985 33 wagon, the 4wd version, its getting a fair bit of engine work done to it soon and ive heard about the alfa g-boxes being fairly.... soft? so i got thinking if there is an alternative gearbox for it or do we just have to bare with the fact that we will be breaking them very often....

 

[active]

Breaking very often is one thing and other thing is braking it every time you want to start quicker. I'm will try to fit gearboxand rear diff from subaru impreza wrx.

 

[77SudTi]

What sort of engines will you guys be running? What sort of power do you think you'll be getting out of them? Peronally I think the boxer gearbox is great, and those who use them for racing dont seem to complain about failures that often. If your sensible with it and are kind to it (ie let it warm up and double de-clutch) I think it will be fine for ~ 170 - 190bhp

For upgrades to the Alfa Box, check out ahmotorsports.co.uk, they're doing some crazy stuff, for a price of course.

 

[Spooty22]

Power doesn't break gearboxes. Torque does.

 

[77SudTi]

indeed, but if you are modifying a boxer engine, I doubt torque figures will be going sky high unless your spending megabucks then probably nothing the boxer 'box can't handle. Perhaps look at uprating the clutch and the input shaft before installing jap crap (no doubt someone will come back with how good jap gearboxes are now...waiting.....)

 

[fly33boxer]

I agree my man, i used to thrash my 16v through the gears and i mean alot of punishing hills changes and the only thing is just the wear factor which will occur in any kind of box.
But if you have a look at the ah motorsport parts they made to replace, it indicated the housing will crack, the drive hubs are a bit weak, and the rear main bearing needs more support......But in saying that they have 260+BHP @ the wheels and i only have 130 so there is a limit they can handle but it would be safe in saying it would be around 160 to 180.
And even if you striving for this kind of power, how would you get it without BIG spendings???

 

[southern75]

Apparently the gearbox starts to get a bit fragile 220hp + ... apparently the biggest issue with the gearbox is flex.

I have been told that the 16v casing as well as those in the latter boxer engined vehicles e.g. 145/146 are more rigid.

The gearbox in the 146 does look slightly different (it definitely has a different linkage setup and sump) Is this for rigidity ... i don't know

However for all intensive purposes the gearbox will cope with most things that you throw at it .... unless you turbocharge.

 

[budweiser_sud]

Here's a spanner to throw in the works...

What about turning a sud/sprint/33 into rear wheel drive? Some people I've mentioned this to have said it would mess up the handling of the sud/sprint/33 chassis, but I'm not convinced. I guess the simplest way would be to use a P4 rear axle/diff and botch a P4 gearbox (which pretty well defeats the purpose as you've got 4WD to start with). Or possibly adapt a Fiat gearbox, driveshaft, axle, diff from a 124, 131 or even a 130 (if you can find a manual 'box. The ZF box fitted to the Fiat Dino, 130 is also the same fitted to the Montreal). 105 series 'box and driveline might be another option. Independent rear suspension would be complex, but certainly doable with enough skill/time. Going mid-engine is the ultimate idea for me (1982 'sud Ti is sitting in my workshop awaiting the angle grinder and the welder!), but front engine RWD really seems a sensible big modification if your looking for a challange. You have the benefit of that low mounted boxer engine to start with and an awesome chassis.

Perhaps I should have started another thread!!

~Benjamin

 

[blacknight]

thanks heaps guys, im actually going to be running the 1.5 8v carb engine with a toyota sc14 supercharger, so i was a little worried bout the gearbox handling it.... but from the sounds of the replies it should be fine.

i might have to start my own thread on the progress of it which should be starting soon.

cheers

 

[PSk]

Sorry guys you are miss informed regarding the strength of Alfa Sud gearboxes. They and the clutch are not strong.

My 170hp Sud turned a rebuilt gearbox into a concrete mixer in a couple of years racing. The gearbox and clutch was fine when the engine was about the 105hp, thus standard.

You will most definitely need to upgrade the clutch and I think binning the gearbox is a sensible idea. Note my car was an inboard braked car and that would not have helped. Also make sure you run the exhausts pipes as far away from the gearbox as practical to ensure you don't cook it ... I didn't and this would not have helped either.

Yes club race guys might get them to last a while, but mine didn't and I'm pretty mechanically sensitive ... and also a seriously raced 33 in NZ in the touring car series went through many gearboxes I believe.

If a Subaru won't work, how about a Hewland from a single seater?
Pete

 

[77SudTi]

A Hewland??.....maybe if you have $$$ leaking from your back passage....

But seriously I have heard pros and cons about the sud/33 gearboxes, and I must say Im a PRO man. I doubt a company like AHMotorsports would make parts for upgrading it if it was a load of dung and should be replaced.

Its all just opinions.........

 

[PSk]

I doubt a company like AHMotorsports would make parts for upgrading it if it was a load of dung and should be replaced.

I guess those parts fix the weaknesses ... if they were strong enough there would be no upgrading required.

A standard Sud gearbox should hardly have the reputation of a strong gearbox, that is just a lie. It's a great little (but heavy) thing, but other gearboxes deserve that strong reputation, ie. Toyota Supra, Ford Cortina (can take 300hp I believe in standard form, or maybe that is only after upgrading too?).

Infact AHMotorsports site proves they are weak and need upgrades, ie: This is what they sell and say:

• SUD/33 UPRATED INPUT SHAFT. Uprated input shaft supplied for unsprung race clutches as the standard ones can break.
• SUD/33 UPRATED PINION BEARING. STD OUTER RACES CAN CRACK DUE TO POOR RADIUS & LARGE UNDER CUT.
• SUD/33 BILLET ALLOY SUMP TO BRACE.
• SUD/33 GEAR BOX END CASING WITH EXTRA BEARING TO HELP FRONT PINION BEARING LOADS.

Pete

 

[Sudmeister]

The Sud diff was only really meant for 60-70 bhp. The 145 for example will break its diff (same as 33) merely because it's so heavy.

 

[active]

What gearbox ratio on 4x4 ? (front, rear ) 50/50? Do the P4 gearbox and rear diff can handle the same amount of torgue as 4x4 ?

 

[lenus]

the 4x4 has no rear dif, and it is a standard 50/50 arrangement. it will just always spin both back wheels at whatever speed the gearbox is turning.

I guess if you take into account the front dif, if all the wheels were spinning more like 66% of the drive would goto the rear wheels between them.

The p4 equipment is out of a fiat panda.

It's already being pushed pretty hard in a p4...

 

[Serpent33]

The gears inside a late 146 models are finer. Which means thay are quieter and filmsier. The early ones have lesser teeth. Having performance clutch can be more punishing to the gearbox than higher hp.

 

[active]

Hm.. but mine has the rear diff. Maybe it's from p4, but the gearbox is defenetly from 4x4. it has manual switching 2wd 4wd. Do all p4 had rear disk brakes? Or maybe some of them still had rear drums?

 

[77SudTi]

sounds like you have a box from an earlier car 4x4 system like the montecarlo wagon or similar where there was no centre diff / viscous coupling. Pretty sure all p4's got rear discs and some 2wd's if you opted for ABS in the later models, yet to see one of them!

 

[active]

I defenetly have rear diff.I saw it ! And about center diff.. is it in gearbox ? 50/50 front rear? or left wheel right wheel?