Author Topic: 75 Performance.  (Read 52507 times)

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Duk

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Re: 75 Performance.
« Reply #90 on: March 05, 2013, 09:17:33 AM »
Is Plastidip a DIY spray can or what? How will it hold up against stones (chips)?

2.5 L bumpers are the same, except the TS ones have the small add-on 'cornices' to meet with the wheel arch flares.

:)

The Plastidip can be bought in spray cans, un-thinned and thinned tins. It can be applied by dipping, brushed or sprayed with a typical spray gun.
How it holds up against stones I can't say yet. It remains flexible so I think it should do well.
An added convenience is that it can be removed by pealing it off as it's almost like a layer of shrink wrap. That makes it easy to spray things like badges without removing the badge from the car. You simply mask of the general area, spray, let dry/cure and then peal away the plastidip from the body, and so long as there is a nice defined edge or gap the coating on the badge will be left behind.

Check out Youtube for videos on the stuff, that's how I got keen on using it.

Duk

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Re: 75 Performance.
« Reply #91 on: May 18, 2013, 05:25:58 PM »
Still some very slow progress with next to no updates  :-[.

Something that I am keen to change about the car, is the location of the charcoal canister.
A significant part of the changes I have made, has been removal of weight forward of the front axle line. The fitting of a non impact absorbing bumper bar and the battery getting moved under the boot floor (1 day  ::) ), will make significant changes (on top of the other changes) to how the car attacks corners. These will be offset somewhat by the bigger radiator, the supercharger and the water to air intercooler's radiator and circulation pump.

So, can anyone name a reason or 2 why I can't move the charcoal canister (for the evaporative emission system) into the boot?
The Adaptonic computer has a dedicated control system to drive a solenoid valve that regulates the purging of the charcoal canister. And with suitable vacuum plumbing, is there any reason why I can't mount the charcoal canister in the boot, near the fuel tank?

Despite the slow progress, on the whole I am really happy with how the car is coming together. My philosophy is to create a car that works well in as many situations as possible. It needs to be reasonably compliant to help it negotiate my favorite piece of treacherous, bumpy, winding back road. And at the same time do all of the normal, boring shit really well (big radiator for the 45* SA summers and 120 amp alternator with some upgraded wiring to help make sure the electrical system works perfectly and reliably over a long period)!

MD

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Re: 75 Performance.
« Reply #92 on: May 18, 2013, 06:07:32 PM »
Sometimes one can get so engrossed in the project upgrades that some really important stuff gets overlooked. No one should ever lose sight of compliance issues. Whatever changes are made need to be legal ones if the car is to be on the road.
Non-compliant vehicles are deemed to be unroadworthy and worse still unisurable. So if such a vehicle was previously registered for road use and its use is recommenced in its altered state without such changes being formerly approved, the use of such vehicle can land the user in knee deep doodoo.

If the vehicle is involved in an accident or causes third party damage,the driver/owner wears all the expenses-at fault or not.

Always a good idea to consult the eventual blue plate certifier AHEAD of time with the intended modifications to be sure that all your work will get the nod.

Now I just know you have planned well.. :)
Transaxle Alfas Haul More Arse.

Duk

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Re: 75 Performance.
« Reply #93 on: May 18, 2013, 06:27:15 PM »
Sometimes one can get so engrossed in the project upgrades that some really important stuff gets overlooked. No one should ever lose sight of compliance issues. Whatever changes are made need to be legal ones if the car is to be on the road.
Non-compliant vehicles are deemed to be unroadworthy and worse still unisurable. So if such a vehicle was previously registered for road use and its use is recommenced in its altered state without such changes being formerly approved, the use of such vehicle can land the user in knee deep doodoo.

If the vehicle is involved in an accident or causes third party damage,the driver/owner wears all the expenses-at fault or not.

Always a good idea to consult the eventual blue plate certifier AHEAD of time with the intended modifications to be sure that all your work will get the nod.

Now I just know you have planned well.. :)

In reference too???

MD

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Re: 75 Performance.
« Reply #94 on: May 18, 2013, 08:17:59 PM »
General advice to anyone modifying their vehicle and to those following your thread.
Transaxle Alfas Haul More Arse.

Southern75

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Re: 75 Performance.
« Reply #95 on: June 13, 2013, 10:14:17 PM »
How do you get to the dipstick ... is there room?
Rust, nah that's not rust .... its iron oxide!!!

Alfas:
1977 Alfasud ti (race)
1980 Alfasud ti (race)
1987 75 V6 (toy)
2008 147 JDTM (sensible?)

Duk

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Re: 75 Performance.
« Reply #96 on: June 14, 2013, 11:15:16 AM »
How do you get to the dipstick ... is there room?

Just.
If need be, I'll extend the handle so it's easier to get.
« Last Edit: June 17, 2013, 04:44:23 PM by Duk »

Duk

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Re: 75 Performance.
« Reply #97 on: October 06, 2013, 11:25:25 PM »
Some progress photos.
« Last Edit: October 06, 2013, 11:27:50 PM by Duk »

Duk

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Re: 75 Performance.
« Reply #98 on: November 08, 2013, 02:55:22 PM »
Have been moving about as fast as road kill lately, when it comes to this thing.
But here is some feedback on the bump steer issues that the Pace Engineering Long Shank Top Ball Joints (LSTBJ) cause.
The obvious behavior of having the LSTBJs was a dramatic increase in toe in with bump travel. Now interwebs research showed that the answer to toe in with bump travel is to lower the outer rod end or raise the inner (raise the steering rack)...................
So I initially bent the passenger side arm to lower the outer rod end, but I started with WAAAAY to much adjustment. Long story short, I bought another upright.  :P
I knew that the R32 Skylines used the same M14 thread for their tie rod ends but the tapered stud is too big. So I bought a good quality, adjustable  bump steer correction kit for the R32 Skyline and machined down the taper so it fits the Alfa's steering arm.

Now, at this point I will mention that I am a huge fan of having plenty of positive caster in my wheel alignment. So using my digital inclinometer I wound 7.5* of caster into it.................

With the new correction kit fitted solidly but in a temporary state (the top nut uses a rather aggressive locking mechanism that I didn't want to have to unwind unless absolutely necessary), I mounted the outer rod end as high as I could, using the kits usual layout and worked the suspension thru some of its travel.
End result, toe in with bump travel.
So I lowered the rod end again.
Still toe in with bump travel.
Lowered it more (by this time I was concerned with the rod end running out of articulation near full droop).
Still toe in with bump travel......................  >:(
In fact, the more I lowered the outer rod end, the more toe in with bump she appeared (at this stage I was just watching the wheel hub move about) to gain.

So I removed the top spacer and put the 2 thinner bottom spacers at the top. Hmmmmmmmmmmm, less apparent bad behavior. And this time I had stuck my little laser pointer to the brake rotor, but wasn't bouncing it off a mirror yet, just watching it wander across the shed wall.

Long story short, after going back over just about every conceivable set up and bouncing the laser off a mirror and back onto a vertical surface I bolted to a wheel stud, I had to reduce my caster angle to 5.5* (only 1 more than standard) and have the thinnest bottom spacer at the top, to get an acceptable (read: really friggin low) level of bump steer.
A quick comparison with an old factory tie rod end shows the new rod ends pivot point is actually higher than where the factory rod end's pivot point would be.........  :o
« Last Edit: November 08, 2013, 05:34:36 PM by Duk »

MD

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Re: 75 Performance.
« Reply #99 on: November 08, 2013, 06:40:07 PM »
   
Quote
Now, at this point I will mention that I am a huge fan of having plenty of positive caster in my wheel alignment.

Hi Dukster,

Just want to say that I used to think that too. However in reality, the 116 transaxles do not need more than 3.5* of caster to work well. I cannot imagine the 75 is any different in this regard.

I am saying this if it helps you solve your set up.
Transaxle Alfas Haul More Arse.

Duk

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Re: 75 Performance.
« Reply #100 on: November 08, 2013, 08:50:42 PM »
Standard caster angle is 4.5* for the 75 (though for some reason I had thought it was 3*).
Caster is a definite helper in trying to keep the outside front wheel perpendicular with the road to help maintain good tread contact patch, during cornering.
The higher roll centre height and the more aggressive camber curve from the LSTBJs, the higher spring rates and eventually chunkier anti-roll bar all help to keep the tyre contact patch much closer to ideal than standard, but I wanted to apply all of the techniques to do the job.
Oh well, I'll have to see how effective the end results are with the set up I have. I'm sure those changes along with the non impact absorbing bumper bar, the battery in the boot and the wider track width will make big changes to the cars ability to turn into corners and should massively reduce the understeery nature of the car.
Tho even when it had 'only' the LSTBJ, 105 lb/in additional coil springs and 4.5* positive caster, it was much improved over standard (well, lower, Koni's and heavy, shite 17x7 rims with a poxy +40 offset).

Duk

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Re: 75 Performance.
« Reply #101 on: December 30, 2013, 07:10:34 PM »
Thought I'd post a photo of my incomplete fabricated front 'bar.
Based on some 1.25" diameter x 0.120" wall thickness 4130 (Chromoly) tube/pipe and uses 40x40x3 RHS arms, it weighs noticeably less than the original 24mm solid bar and calculations show that it should be about 60% stiffer too. Or about the same stiffness as a solid 27mm bar.
« Last Edit: January 04, 2014, 03:28:00 PM by Duk »

Colin Edwards

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Re: 75 Performance.
« Reply #102 on: April 24, 2019, 01:10:07 PM »
Further to the performance of the 3.0 12V fitted to the 75, exhaust system work for the old girl needs serious consideration.  Specifically from the heads - but not including the rear muffler section.

Two design philosophies appear popular with regard to the headers:
* A virtual copy of the cast headers - fabricated three into one, featuring primaries around 500mm long
* Fabricated headers - two piece / joined primaries about 1200mm < 1500mm long - three into one collector located somewhere under the hand brake

Given the second arrangement would be near three times the weight of the first arrangement, would the extra mass be offset by any "PROVEN" engine output increase of the more complex solution?  Not looking for much performance increase.  Just don't see the point in adding mass for very little (if any!) gain.

Engine is as per factory apart from SZ cams and re-profiled / lightened inlet valves.

Colin

 
« Last Edit: April 24, 2019, 04:01:01 PM by Colin Edwards »
Present
2020 Giulietta Veloce
2018 Abarth 124 Spider
1987 75 3.0

Past
2015 Giulietta QV
2009 159 3.2 Ti Q4
2012 Giulietta TCT Veloce
2006 147 Ti 2 door Selespeed
1979 Alfasud Ti 1.5

Duk

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Re: 75 Performance.
« Reply #103 on: April 26, 2019, 01:49:30 PM »
Making sure the pipe lengths are as close to equal as possible is very important.
A tubular version of the original manifold is basically pointless. When decent factory exhaust manifolds started to apear on equally decent engined cars, less than honest manufacturers would simply build a tubular version of those manifolds and claim improvement over the original manifold.
But unless the diameter and/or lengths are changed, how can there be any change in exhaust chacteristics???
Basically there can't be any changes if things are ultimately very, very similar.

1 good thing about the shorter primary pipe extractors is that it can be worthwhile to play with secondary pipe lengths and diameters to further chase power or a broader torque curve.

Personally I'd use 500mm primaries, 1 5/8", equal length pipes, with proper merge collectors and look at secondary pipes at least 700mm long, 2" diameter into a 2 1/2" collector before the cat.
Whether you could buy those extractors off the shelf or not, is anyone's guess.
The Daily: Jumped Up Taxi (BF F6 Typhoon). Oh the torque! ;)
The Slightly More Imediate Project: Supercharged Toyota MR2.
The Long Standing Conundrum: 1990 75 V6 (Potenziata)............. What to do, what to do???

Storm_X

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Re: 75 Performance.
« Reply #104 on: June 16, 2019, 07:05:42 PM »
So how's the car going now, has much happened in the 6 years from the last update
"Alfa Romeo built to excite.. Some dream of driving the ideal.. I drive it"