Alfa race transmissions - Page 2

genericwood · #16 (**permalink**) 06-06-2006, 08:51 AM

You may also want to post your request for a 4-speed on the 750/101 list on YahooGroups. I put out a request a couple years ago and had several offers in the $50-$200 range. There are a TON of Giuliettas that have been upgraded to a 5-speed. The 4-speeds that are removed are sitting under benches and in sheds. You just have to shake them out! You don't even need a complete 4-speed. I think all that Schwitters needs is the input shaft/gear assembly and the layshaft.

My brother has the Schwitters Hewland box. Right now he is running an underdrive 5th, something like a 1.18 ratio!

Erik

gtvracer · #17 (**permalink**) 06-06-2006, 08:54 AM

Hey, Thanks again. It is great having all of this help from experts.

Jason

OldAlfaGuy · #18 (**permalink**) 06-06-2006, 04:36 PM

I remember reading that Horst Kwech found on his Trans Am cars that the Alfa gearboxes (i.e., GTA close ratio) were marginal with the power of the racing 1750, and definitely not up to a race-prepped 2 liter. (After all, they were designed for horsepower and torque of a 1.6 liter.)

I was also told that the Colotti gearbox and any gearbox with Hewland internals is OK behind high power Alfa 4 cylinder engines.

Alex · #19 (**permalink**) 06-07-2006, 03:17 AM

Didn't I also read somewhere that Kwech made a (totally illegal) six-speed gearbox, using the reverse throw for top?

alfabender · #20 (**permalink**) 06-07-2006, 01:55 PM

I am the proud owner of not one but two Colotti transmissions that I bought on ebay a couple of years ago (from a fellow BBer I think). They are sitting open on my workbench right now. To answer a couple of the postings above:

1) The Colotti boxes could be made into a 6-speed by modifying reverse. I would guess the same is true of a stock type box. I think I saw something here on the BB about someone here local doing that--perhaps Al Cortez.

2) The Colotti boxes don't look to me like they can take a lot of horsepower for extended times. The gears are straight cut with really coarse teeth-in several cases only one tooth at a time is contacting so they aren't sharing the load between teeth. Also there's quite a bit of backlash which is why the box is so noisy. I took the box to a local gear shop and the guy there just shook his head, then showed me gears he was making for 500 hp offroad vehicles--finer pitch and several teeth sharing the load at any given time. Several of the gears that came in the two boxes I got are pretty well worn so I ordered some new ones from Colotti--big bucks! I'm happy to run these trannys with a 1600 but I think with a 2-liter I'd go with a close-ratio stock type setup like you can get from Alfaholics or Anthony Rimicci.

Doug Bender

Max Banks · #21 (**permalink**) 06-07-2006, 02:10 PM

Just so you guys know, we are in the middle of doing a batch of absolutely 100% as per original GTA gear clusters which will feature all the scoopings and drillings of the original gears, we are also toying with the idea of rifle drilled main shafts as per GTA. We are using a gear cutting company that supply Williams F1, Jordan/Midland F1 and BAR so quality should be better than anything we have seen so far.

The project came about from retiring Richard's original GTA box fromt he racer, as we thought 6 seasons racing with over 200bhp was probably enough for the box and that it should go back into Richard's 1600 GTA road car. We then bought an Italian cluster that will remain nameless and it was a horrible thing to use, baulked changes and a reverse gear that bearly worked. This was when we decided to do it ourselves... which is how we have got to where we are now!

pinshaw · #22 (**permalink**) 06-09-2006, 09:50 PM

if you still need one, I just posted 2 5 speed boxes, one from a 63 spider, the other from a 67 GTV. Replaced both with CR boxes from schwitters. 63 has a cr 5th gear from Autodelta; 67 is stock Peter

Max Banks · #23 (**permalink**) 06-13-2006, 09:13 AM

Quote:

Originally Posted by OldAlfaGuy

I remember reading that Horst Kwech found on his Trans Am cars that the Alfa gearboxes (i.e., GTA close ratio) were marginal with the power of the racing 1750, and definitely not up to a race-prepped 2 liter. (After all, they were designed for horsepower and torque of a 1.6 liter.)

I was also told that the Colotti gearbox and any gearbox with Hewland internals is OK behind high power Alfa 4 cylinder engines.

Dick NL · #24 (**permalink**) 10-10-2007, 04:19 PM

Hello, just recently discovered this forum. I am racing a 1973 Alfa GTV in the Dutch Alfa Romeo Challenge. Have been reading a lot about the "Schwitters dogbox", but I cannot find a website or adress details to contact the constructor or a reseller. Can anybody help me out?
regards, Dick

**Zunige** · #25 (**permalink**) 10-10-2007, 04:32 PM

Quote:

Originally Posted by Dick NL

...the "Schwitters dogbox", but I cannot find a website or adress details to contact the constructor or a reseller. Can anybody help me out?
regards, Dick

Curtis · #26 (**permalink**) 10-10-2007, 04:32 PM

Dick,

"Schwitters gearbox" can mean a lot of different things.

Steve makes a close ratio synchro box with stock 1st.

He makes a close ratio synchro box with a 1.99 1st.
These boxes have far superior ratios (for pure racing)
than the original factory close ratios.

Steve also converts Alfa boxes to Hewland Mk 5 internals
with either a fixed 1:1 4th, fixed 1:1 5th, or an all gear
ratios variable like I run. These are non-synchro dog
engagement boxes.

Not sure what he uses for a business phone however if you
will leave me your contact info at curtis@thiscrazygarage.com
I would be happy to have him contact you, or give you his
phone number.

I do know he does not have a web site.