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Re: No longer a ''budget" race GTV

Posted: Sun Oct 30, 2011 9:15 pm
by kevin
My camber finished off at 2.5 degrees. So far i am getting fairly even wear . Remember i am running similiar set up to rons car with 200 kg springs upfront and no torsion bars . The factory 75 touring car that came here begining of year was 0n 2 degrees, but yes different suspension geometry.

Re: No longer a ''budget" race GTV

Posted: Sun Oct 30, 2011 10:24 pm
by GTV27
I'm fairly sure mine is -3.5 camber (have yet to check my file). I had about -2 in it previously but it was destroying the shoulders and went up some to try and keep my tyres alive for more than 3 laps!

It is, however, still in road-car spec. I am running 28mm torsion bars, which I guess the wheel rate to be 280ish (or about double the standard bars) and a 24mm ARB, so I suppose that must still be a lot less stiff that a 'proper racer'? As it doesn't see track time anymore (and is not likely too for the foreseeable future) I really should decamber it...

Re: No longer a ''budget" race GTV

Posted: Mon Oct 31, 2011 7:21 am
by 75evo
I have -3* in the front and -2* in the rear. The rearvwill be widened via spaces too, maybe by 1" on each side. I can only test it at Laguna Seca on new year's eve. Also gonna get a compression increase to 11:1.

Only thing I'm a little worried is the rear has 0 toe-in, so under braking could be a little less stable with the added camber.

Re: No longer a ''budget" race GTV

Posted: Mon Oct 31, 2011 9:22 am
by Giuliettaevo2
My road car had 2.5 degrees camber, as much caster as possible i believe it was 8 degrees and zero toe in/out. very neutral handling was the result, but this was a Giulietta with TS, not a heavy v6 in the nose. :wink:

Also 30mm AR bar and yellow koni's all around, almost fully closed up front and half open in the rear. no AR bar in the rear.

Re: No longer a ''budget" race GTV

Posted: Mon Oct 31, 2011 9:35 am
by kevin
I used to run 3.5 degrees three years ago but as the suspension became stiffer (upgrade to pure track) I monitored tyre wear and temp and thats how I ended up at 2.5 deg . Also helped with braking.
1deg toe in on rear would be great but I must do more track time and finish other cars off. (got to change lower controls ,cv's,AR on GTA wagon - its a sh*t job as I stripped on Sunday.

Re: No longer a ''budget" race GTV

Posted: Thu Nov 03, 2011 9:34 am
by Mats
I hope you mean 1mm of toe-in? 1 degree of toe-in is crazy!

Re: No longer a ''budget" race GTV

Posted: Thu Nov 03, 2011 11:43 am
by kevin
Youre right 1mm :D

Re: No longer a ''budget" race GTV

Posted: Mon Nov 07, 2011 12:55 pm
by kevin
Greg , i have two spare torsioj bar adjusters . It works out to 760 us dollars. Pm if anyone is interested. I have found out i can only do three international transactions in one year according to my country laws so maybe i would have to swap it for some patrs overseas :D
Yeah , i dont want to be a vendor here and apply for a tax break.
I must still find weight of unit. I would definitly trade for a set of 36mm torsion bars :D

Re: No longer a ''budget" race GTV

Posted: Mon Nov 21, 2011 10:55 am
by kevin
Here some pics of Race day on Saturday. We had 33 entrants and mixing in with the American muscle cars at the same time.
As usual there were only two clowns who drove to the track and home after the race and in a proud way I was one of them as it meant nothing broke. On the positive note I had 5th fastest time of the the day. This included the cobras, daytona, and other Alfas but finished in a poorly 15th as a cobra stalled on startline and I was stuck for 30 seconds(and another lightweight Giulietta) behind it while the rest of the field were long gone. Not even 1 second seperated the top 5 fastest cars.Anyway I will post later on what were the positives on the car
Ps the speedometer is just for show incase the feds pull me over.

Re: No longer a ''budget" race GTV

Posted: Mon Nov 21, 2011 12:03 pm
by kevin
After reading Jims book , i decided to relook into the engine oil department . I have been using a Shell 15w40 which has been good for road use but under track conditions and hot weather the oil pressure has been dropping to scary 2bar at 120 degrees (4500 rpm) Remembering this 24v motor has hydraulic lifters and combined with forged pistons its needed a bit of experimentation but in the right direction . I think i have found solution and decided to change oil after qualifying with a castrol edge sport 10w60 . I managed to gain a further 0.8 bar but im still not to convinced its even close to perfect but its now its 2.8 bar at 4500rpm at 120 degrees . My water temp was only 80 degrees which has come down since i have opened up the front bumper.
Some questions to you guys
Should my oil temp be getting that high in these hot racing conditions . (track temp was 34 degrees) even with an oil cooler.
Whats a minimum pressure you should be running ?
Even after opening up bumper to get air in I still forgot to take my number plate off for race - i totally forgot as I was running out of time trying to bleed brakes and change oil.

Re: No longer a ''budget" race GTV

Posted: Tue Nov 22, 2011 11:16 pm
by MD
Kevin,

A lot of NA race engines use that oil over here without any problems. Maybe your oil pump needs to be rebuilt to closer tolerance. I think the oil pressure should not fall below 40 psi.

The water temp is way too low at 80*. Your combustion efficiency is crap. It should be close to 100*C with appropriate additives and pressure. I run the Cab at 98*C.

Re: No longer a ''budget" race GTV

Posted: Wed Nov 23, 2011 1:03 pm
by kevin
Md , i hear you but if i have 7 bar at start up and gradually loses pressure as heat increases is it a tolerance issue ?
Next question what would you set the temp forfans to kick in andthen what temp to switch off . Maybe i am engineering my own problems here

Re: No longer a ''budget" race GTV

Posted: Thu Nov 24, 2011 1:03 am
by MD
Yo Kevin,

Far out man ! 7Bar oil pressure that would be way more than you need and a waste of horsepower. I had 5.5 on the Brick at the start, no oil cooler, ran a 20W60 oil and never had a pressure problem. IE. it remained above 2.7 which in my view is OK.

I cannot remember if you're using an oil cooler on the engine or not but it sounds like you should. If you are already using one, then I am fresh out of ideas for you.

As for the temps, well kick the fans in around 102-3*C and switch off at 95*C. Currently I am not using a fan at all and just let the forward motion of the car do the heat exchange and remember, our tracks are in the sub-tropics.

Re: No longer a ''budget" race GTV

Posted: Thu Nov 24, 2011 10:30 am
by Giuliettaevo2
MD wrote: just let the forward motion of the car do the heat exchange
And that's the way it should work me thinks :) ... the fan should really only be needed when driving slowly in traffic or standing still.

Off course i can say that since our local temp very rarely exceeds 40 degrees celsius. :wink:

A bigger oil cooler sounds like a good plan if you get up to 120 degrees with the current one. I believe 130 degrees is the breaking point for oil, after that it start degrading quickly.

My friends use the Castrol Edge 10w60 stuff in their turboengines and speak very highly of it.

Re: No longer a ''budget" race GTV

Posted: Thu Nov 24, 2011 6:48 pm
by GTV27
The old rule of thumb is 10psi oil pressure for every 1000rpm - so if you have 2.8bar (about 40psi) at 4500rpm you are just under par.

120 deg is not outrageously high for a modern synthethic oil - the high temp rating for viscosity levels is at 100deg - but I think your move from 40 to 60 was well advised.

Agree the coolant temp seems low - is the thermostat working?