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With std management and turbocharger, if you use a 10548... intake cam, an aftermarket fuel pressure regulator, a special (O-ring) head gasket, head milled for 8:1 CR and a max boost of 1.2bar (18psi) you can see a max of 210-220hp (engine) and 310-320Nm (~230ftlbs) torque while keeping afr ~11.5-12.5:1.
If you install the Marelli management system from the old Ford Sierra Cosworth 2wd car and a modern snail, you can easily see 290-300hp -after mapping of course.
Jim K.
 

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Discussion Starter #4
With std management and turbocharger, if you use a 10548... intake cam, an aftermarket fuel pressure regulator, a special (O-ring) head gasket, head milled for 8:1 CR and a max boost of 1.2bar (18psi) you can see a max of 210-220hp (engine) and 310-320Nm (~230ftlbs) torque while keeping afr ~11.5-12.5:1.
If you install the Marelli management system from the old Ford Sierra Cosworth 2wd car and a modern snail, you can easily see 290-300hp -after mapping of course.
Jim K.
Which turbo is that with?
 

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The GT3071R will do all that at 1.7-1.9bar (~26psi) with a good front-mount intercooler. However, I believe you can have a much more useful power band with a GT2871R.
These engines can take more than 2.5bar (36psi) and are good for close to 500hp with race gas! Don't ask for how long, the people that have them rarely flog them for more than a mile or so!
Jim K.
 

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Discussion Starter #6
Excuse my limited knowledge.....running the 10548 cam and keeping the original intercooler, what could I have the standard turbo rebiult/upgraded to without going to a GT2871R, for cost reasons? Would there be any advantage to running the Cosworth ECU as these here in the UK are CHEAP. Trying to build a good £ per bhp motor.

Regards

Jonathan
 

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The std snail will not last too long with boost exceeding 1bar (14.7psi). The way to make it last up to 1.5-1.6bar is to rebuild it with a 360* oiling thrust bearing. However, there's a downside to this, it will take longer to spool up...You will have to wait until 3400-3600rpm before you can start smiling! The original intercooler is fine for road use but in the track it will heat up soon after a few laps -depending also on outside temperature of course.
The Cosworth setup is good if you want to run higher boost than ~1.3bar (19psi) the reason being the ability to map suitably on the dyno, which you can't do with the std management -at best, you can install a special chip in the ignition ecu which will allow operation to over 1bar. Couple this with a manual wastegete bypass valve set at a max of 1.2bar, a good aftermarket fuel pressure regulator (ie Aeromotive) a little drop in the static advance (from 8* to ~3*BTDC) and with a good exhaust system you're on your way to ~210hp. Hope this is enough to help you decide!
Jim K.
 

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Discussion Starter #8 (Edited)
Thinking ahead, if I'm to use a front mount intercooler I need a plenum with a forward mounted throttle body that attaches to the standard manifold that comes off the head. Anything out there? Also if I'm to run a different turbo then possibly a different exhaust manifold as well. This is not a "throw money at it exercise" so if anyone has any bright ideas?


Regards

Jonathan
 

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I'm sure Luis will take some notes for the Turbo Evoluzione.....

Thanks, Jim.
 

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Thinking ahead, if I'm to use a front mount intercooler I need a plenum with a forward mounted throttle body that attaches to the standard manifold that comes off the head. Anything out there? Also if I'm to run a different turbo then possibly a different exhaust manifold as well. This is not a "throw money at it exercise" so if anyone has any bright ideas?


Regards

Jonathan
I *think* the non ts, bosch injected 4cyl 75s (and late rwd spiders) have a manifold that will do the trick, doesn't face forward though, but should be better than the turbo one for a FMIC. Alternatively, a TS 75 plennum section should fit, but it has a forward facing throttlebody but it's at the back of the manifold.
 

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Hi All,

Without going mental, what can be achieved with this engine power wise?
The usual old school turbo tricks should work well:

Free flowing exhaust. 3" is preferred but 2.5" is probably fine. Twin 2.25" pipes under the car for 3" will give better ground clearance for the low points. Mandrel bend for all bends. 'High flow' muffler and cat (if fitted).
A good dump pipe of the back of the turbo is probably a good idea (never seen Alfa turbo engine in the metal).

Make sure the turbo can get all of the cool air it can use. Pod filters under the bonnet (pod filters in general, actually) are total BS. Making sure the air gets into to filter housing, out of the filter housing into the AFM and then to the turbo with minimal flow restriction will achieve best results.

Some extra boost pressure via a bleed valve is straight forward.

Then you could try something like a capacative discharge ignition system like an MSD6A for the poor old distributor based ignition system, colder plugs and bigger plug gaps.

Check air/fuel ratio's to make sure they are safe (no leaner than 12.5:1) and listen for detonation.
 

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Discussion Starter #12
I *think* the non ts, bosch injected 4cyl 75s (and late rwd spiders) have a manifold that will do the trick, doesn't face forward though, but should be better than the turbo one for a FMIC. Alternatively, a TS 75 plennum section should fit, but it has a forward facing throttlebody but it's at the back of the manifold.
OK, looks like the inlet manifold problem is sorted, now I've got to try and sort out an intercooler, I'm thinking of something that is mainstream that I can have modified with the appropriate bracketry, some sort of aftermarket Audi/Golf or the like....any suggestions?

Regards

Jonathan
 

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OK, looks like the inlet manifold problem is sorted, now I've got to try and sort out an intercooler, I'm thinking of something that is mainstream that I can have modified with the appropriate bracketry, some sort of aftermarket Audi/Golf or the like....any suggestions?

Regards

Jonathan
Ebay for intercoolers... they're cheap, in a bunch of sizes and configurations. Sure, the cheapy chinese universal ones aren't quite as efficient as the super spendy ones, but they'll be a stack better than the factory setup, and you can always just go a size larger :)
 

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Head gasket has gone on my 75 Turbo Evo - want to keep the car original spec but any suggestions as to the best head gasket - am based in the UK

Cheers for any recommendations
 

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Your best bet is to get a 2-piece (with steel O-rings) from Nava, Italy. Comes in two thicknesses, 1.6/1.9mm. We run these for years up to 2.5bar+, no problems ever.
Jim K. Cost is ~200€ now.
Jim K.
 

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75 turbo head gasket

Thanks Jim

The 80029 is 1.9mm and I presume this is one to go for if head skimmed 1mm.

Do you know the part number of the correct 1.6mm standard gasket from the page below -assuming head only has light skim and not wanting to lower compression ratio?

 

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I used to have a 1.8 Turbo too. What I did was:

I decided to keep the original intercooler because the boost line is very straightforward and you don't get any lags when you need boost but in other way, the original intercooler is not so effective for high performance (230+HP) applications. I transformed the intercooler to a water-to-air intercooler and installed a tiny radiator and used an electric pump from Subaru Legacy to circulate the water and I got IAT around the ambient temperatures. This can be modded for better performances. This is the most effective way to lower the IAT. Some people choose to use FMIC's and proudly show them but I don't like a car seems like crushed into a radiator and turbo lags...

Keep the original turbo because it generates the boost just your engine can get. That is why you don't get any compression surges under any circumstances without any dumpvalves. It will be all right for any setup below 250 HP. In fact you wouldn't want more than that power because the driveline of these cars especially the shaft donuts and transaxles can't deal more power and they won't last long; also in other way any 1.8 Turbo which producing around 230ish HP is a very fun car to drive. It is not as heavy as the V6's and much more powerful than any model of Alfa 75's.

You can choose to keep the original ECU and use bigger injectors and/or higher petrol pressure to deal with the need of rich A/F mixtures under boost but it would be very vise to choose a modern, intelligent engine management system and get it tuned by a specialist. Your car would be much more powerful, economic and reliable then the stock ems when especially after getting this job done good.

Also you can use some tools like turbo-times boost controllers to make your life easier.

My car was a 230HP car and I really miss the way she drives. I was getting 165HP with 0.4 bars boost and 230HP with 1.2 bars boost.

Best wishes for your car.
 

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Dont think so... maybe with a different head gasket, standard 1.8 turbo runs 0.6-0.7 and still blows its head gaskets so regular one wouldnt hold on that boost.

Also think of the compression rings, they could maybe take it for a short while but arent really made for boost.

Safe answer is no then, but there are TS engines with standard pistons from 1.5 boxer running 1 bar of boost so in that regard maybe....
 
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