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Re: From Road car to Race car - Alfa 33

Posted: Mon Sep 29, 2014 11:29 pm
by SteffenJ3316V
If max is 7 kg pr bhp you are only allowed 134 bhp. Is that wheel power or crank?

Re: From Road car to Race car - Alfa 33

Posted: Tue Sep 30, 2014 8:08 am
by Brovold
According to the sheet, with all it's +/- for different settings, I'm currently on:
- weight 920kg (could reduce to 853kg according to calculation with original engine)
- effect 120,01hk (calculated)
- 7,666 kg/hp (calculated)

This gives me the window to change ECU and tires to 205/50/15, and end up with 7,041 kg/hp (limit is 7,000 kg/hp)

I forgot to mention that I have a 1.5 gearbox

Regarding lap times, there is 3 different tracks we're using:

Sweden, Gelleråsens Motorbana - flat, curvy circuit where the car have good tracktion. Never completed a race there, but have good laps times.
Norway, Vålerbanen - flat, curvy circuit. Here I have track record for my class, so no problems when engine is ok :-)
Norway, Rudskogen - high speed circuit with steep hills. Last year I did lap times of 1.47.00, but last race only 1.49.00 (winner in class had 1.45.00)

So my challange is not the small, curvy tracks, but any track where top speed is an issue....

Pål

Re: From Road car to Race car - Alfa 33

Posted: Tue Sep 30, 2014 9:07 am
by PETROLHEAD
Are you revving out on the bigger circuit, or finding the car will not pull up to the rev ceiling on the biggest straights?

I'm thinking back to the point Bryan made earlier, that exiting onto the straights quicker, with the use of an LSD, would change things significantly, but how does your car suffer for top speed at these bigger open circuits?

Re: From Road car to Race car - Alfa 33

Posted: Tue Sep 30, 2014 2:55 pm
by Brovold
petrolhead wrote:Are you revving out on the bigger circuit, or finding the car will not pull up to the rev ceiling on the biggest straights?

I'm thinking back to the point Bryan made earlier, that exiting onto the straights quicker, with the use of an LSD, would change things significantly, but how does your car suffer for top speed at these bigger open circuits?
I have same/higer speed out of corners, but suffer mid/end on straights. Feeling good speed up to 3rd gear, then "empty" and the others thunder past me

Re: From Road car to Race car - Alfa 33

Posted: Tue Sep 30, 2014 3:11 pm
by SteffenJ3316V
If it's a 1,5 gearbox from a S2 ti or a S3 ie it has the same gear ratios as the 16V

Re: From Road car to Race car - Alfa 33

Posted: Tue Sep 30, 2014 3:24 pm
by Brovold
Last year I just used 4.th gear, this year 5.th on the high speed track - so there must be some difference.

Re: From Road car to Race car - Alfa 33

Posted: Tue Sep 30, 2014 3:27 pm
by Johnboy
Here you go ;)

Re: From Road car to Race car - Alfa 33

Posted: Tue Sep 30, 2014 4:54 pm
by SteffenJ3316V
Brovold wrote:Last year I just used 4.th gear, this year 5.th on the high speed track - so there must be some difference.
Then it's not a 1,5 ti or ie gearbox :)

Re: From Road car to Race car - Alfa 33

Posted: Tue Sep 30, 2014 7:18 pm
by KevJTD
fit a 1.2 ti gearbox, you will be able to use the gears then and keep it in the higher rpm's
worked a treat in my old sud, 16V engine with 1.2 'box.

i've got a couple here ready for check over/rebuild

Re: From Road car to Race car - Alfa 33

Posted: Tue Sep 30, 2014 8:02 pm
by Brovold
When buying the gearbox, it "was" a 1.2 but based on experience - it's not. It's to close to the original 1.7, but as mentioned there is some difference.

My fear is that a 1.2 is running out of gears on the high speed track. Today I shift to 5th 100-200m before the end, so it might be enough with a 1.2...??

Re: From Road car to Race car - Alfa 33

Posted: Tue Sep 30, 2014 8:26 pm
by Brovold
Here you can enjoy tha last video, tge summery of 2014

http://youtu.be/LYNJ-QzY2mM

Re: From Road car to Race car - Alfa 33

Posted: Tue Sep 30, 2014 8:41 pm
by KevJTD
Brovold wrote:When buying the gearbox, it "was" a 1.2 but based on experience - it's not. It's to close to the original 1.7, but as mentioned there is some difference.

My fear is that a 1.2 is running out of gears on the high speed track. Today I shift to 5th 100-200m before the end, so it might be enough with a 1.2...??
the 1.2 ti 'box not only gets a low diff ratio but the gears themselves are pretty close together, making all 5 gears useable.
without spending a fortune on a bespoke gearbox with special gears i'd say it's a great choice for track use.
the main advantage is that the revs don't drop down that low as you go up the gears so the change from 3rd to 4th keeps the engine in it's main power band and doesn't feel to bog down, same again into 5th.

Re: From Road car to Race car - Alfa 33

Posted: Tue Oct 07, 2014 7:59 am
by Brovold
Here is video from race 9, and you can see the difference in speed. A good start from 9th place on the start grid, up to 2nd for a few seconds in turn two, and then down to 4th when the others find their direction again. The 75 have turbo, the Sud carburetors, and the 156 you can see in the drivers mirror the hole race have V6.

The 156 is "the car to beat" regarding over all victory in class 4, but after 6 rounds I'm not able keep him behind me any more, so he takes the victory. The camera goes empty of power before this, but you can see his last attack just before it goes black....

http://youtu.be/TBHAVhLSXQk?list=UUHNI2 ... MTr--9llyA

And here the same race from another car:

http://youtu.be/XbF06FUB7Jc

Re: From Road car to Race car - Alfa 33

Posted: Thu Oct 09, 2014 9:55 pm
by Veesix75
What max rpm are you using before changing gear?

It's hard to tell from the video, but 5th seemed to drop low down in the revs on the odd time you used it.

Even with a 1200 gearbox it's surprising how little 5th is used on tighter circuits - I pulled 5th once on a lap of Brands Indy. I use it twice at Donington, and twice at cadwell.

I might be wrong, but you might need a few more rpm before pulling 4th and 5th, or holding it in 4th at the end of that run in the video might be faster than going up to 5th and then straight down again?

Re: From Road car to Race car - Alfa 33

Posted: Sat Oct 11, 2014 9:51 pm
by PETROLHEAD
I agree with you there Tim,

the moments in fifth don't sound like they allowed any useful acceleration, and simply flattened your approach speed.

hanging on to 4th might feel harsh, but would probably result in a quicker arrival at the next turn by the looks and sounds of it Paul.


what do you think from in the cockpit?

Re: From Road car to Race car - Alfa 33

Posted: Sun Oct 12, 2014 10:33 am
by Brovold
From cockpit I feel the engine is missing 10-20% power from 4000 rpm and up. It feels slower and not that responsive as it did earlier this summer. The start was ok, so 1st and 2nd gear worked, but from 3rd and up it strugles. Don't know if it's low fuel pressure, a valve gone bad, exhaust leak or something else.

You can see it in this film, same track but earlier this summer. Here I feel the engine gives me all it's power:

http://youtu.be/tJ8k89KRdi0

Well, I have to pick the engine out, split it and see.....

Pål

Re: From Road car to Race car - Alfa 33

Posted: Fri Oct 31, 2014 11:05 am
by Brovold
I see that in another tread here, there is talk about an rear ARB to prevent body roll, but could someone post a pic/explain this to me? Not sure I understand how to do this on an fixed rear axle like the 33....

Pål

Re: From Road car to Race car - Alfa 33

Posted: Fri Oct 31, 2014 11:10 pm
by BS25
Hi,

We designed our own, here's a few pics. I apologise in advance for the state of the car, the pics were obviously taken after a wet race!

Re: From Road car to Race car - Alfa 33

Posted: Sun Nov 02, 2014 4:23 pm
by Brovold
Thanks!

Make more sense witth pics :-)

Pål

Re: From Road car to Race car - Alfa 33

Posted: Fri Nov 07, 2014 7:33 am
by Brovold
New question:
- anyone done an adjustable cam pulley?

I know I can buy this, but a bit steep price when you need 4:

http://www.gazzellaracing.com/product.p ... ctid=20245

Thinking about new ECU and to put the engine in a dyno for trimming, and one of the guys asked if the cams are adjustable or if it's possible to make them adjustable. He had a set for a 8V where they had made one adjustable out of two pulleys by cutting out the inner/outer part, and made sliding holes for adjustments.

Pål

Re: From Road car to Race car - Alfa 33

Posted: Fri Nov 28, 2014 4:14 pm
by Brovold
Just to give you a quick look at our series here i Norway, here is this years collage

Re: From Road car to Race car - Alfa 33

Posted: Fri Nov 28, 2014 10:10 pm
by PETROLHEAD
Some fine pedigree in there Pal, and check you out looking all menacing too! :twisted:

Lol!

Re: From Road car to Race car - Alfa 33

Posted: Fri Nov 28, 2014 11:34 pm
by Brovold
When speed is to low, a mean look is a good substitute - but next year.....next year speed will be no issue ;-)

Re: From Road car to Race car - Alfa 33

Posted: Sat Nov 29, 2014 11:07 am
by Veesix75
I like the Fiat x19.

We don't have the same variety of Italian cars racing over here since the old Auto Itala series ended.

I can't remember when I last saw an old Fiat racing, just the odd Lancia.

Re: From Road car to Race car - Alfa 33

Posted: Fri Dec 12, 2014 10:39 pm
by Brovold
Engine out and part of this years xmas gift to myself test mounted :-)

Re: From Road car to Race car - Alfa 33

Posted: Sat Dec 13, 2014 1:22 am
by mbakermarco
Johnboy wrote:Morning

If your keeping it white then go for the black and white , but if it was black the go for the flag ;) both look cool
I agree Johnboy !

Re: From Road car to Race car - Alfa 33

Posted: Sat Dec 13, 2014 1:26 am
by mbakermarco
Veesix75 wrote:I like the Fiat x19.

We don't have the same variety of Italian cars racing over here since the old Auto Itala series ended.

I can't remember when I last saw an old Fiat racing, just the odd Lancia.
I raced in the AutoItalia championship for a few years and absolutely loved it - reverse grids, rolling starts - really good racing ! I started with a Fiat 127 Sport, so I was usually on the front or second row, so the first lap or two really focused ones attention I can tell you, with all the quicker cars coming through, sometimes not at all politely lol ........

Re: From Road car to Race car - Alfa 33

Posted: Wed Dec 17, 2014 2:12 pm
by Brovold
Ok guy's, need your input agian on choosing ECU. The options are:

Megasquirt 3
Megasquirt 2
Haltech Sprint 500

The guy with the dyno know's this systems, so this is not a problem, but my wallet would like your inputs.....

Pål

Re: From Road car to Race car - Alfa 33

Posted: Wed Dec 17, 2014 2:18 pm
by AlfaCorseChris
Sorry mate, cant express any opinions here as I've never tried megasquirt.

I run on OMEX ecu

Re: From Road car to Race car - Alfa 33

Posted: Wed Dec 17, 2014 6:44 pm
by PETROLHEAD
If it were down to just those three options and nothing else, i'd probably go Haltech,

Historically, Megasquirt, are so , err, Ford! :x

:mrgreen: :mrgreen: :mrgreen: