Q4 modifications - Alfa Romeo Forum
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Q4 modifications

Thanks for all the info so far guys. Here's a few more questions though:

I have bought the larger turbo (T34) from the early evo integrale which should give me up to 1.5 bar peak boost, holding say 1.3 bar. What other engine mods would be recommended to both improve performance and ensure some amount of longevity?
I was planning tubular exhaust manifold, custom exhaust, thicker head gasket, freeflow airfilter and custom written chip. Have I missed anything?

Will the standard intercooler be sufficient or would it be wise to install water injection activated by a pressure switch? Also How can I check that the intercooler water jets are working?

I guess the clutch will need uprating too as I reckon near 300bhp should be realised with these mods, which is the one to go for?

Suspension: the front needs attention as it clatters a bit over bumps, I just ordered new wishbones, anti-roll bar bushes and Eibach springs to fit during the rebuild. Does anyone know how much new standard shockers are and would it be better to ditch them and get bilsteins or konis? My car car has done 74k miles and still has the original ones so I guess they could be a bit worn out.

I know there are a bunch of questions here but bare with me, I've just got the Q4 and I'm sucking up all the info I can.

Cheers guys,

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as i remember form a post ages ago you should already have water injection it just needs connecting up...if you look in the side pockets in the boot you should find a spare water tank.
maybe someone can comfirm this before i look a right wally... eek!
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Different things Jimbob, the car has water jets for the intercooler, Water injection would inject direct in to the airfeed (from the turbo) to the plenum.
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If you got a Garrett TB0385 check with GibbonQ4, he has fitted one to his car and combines it with Tipo 16V inlet cam. I do think Bazza at Evocars have chip ready to plug in for that configuration. If you are thinking of more upgrades I would recomend the intercooler before 300 hp. The intercooler itself isn't that bad but the air feed is below all criticism. Then if you're not heading for the really extreme power levels it's better to keep the compression ratio standard. A good example is the configuration mentioned above combined with increased CR to 8.5:1 by milling down a mm from the block that gives 270 hp at 1.0 bar boost. Then you will have a lot of bottom torque and much better response as a bonus.

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As andreas says.. you can go down one of two routes.. low compression, big boost & lots of BHP, or higher compression, lower boost & more drivability.

Moving the intercooler is worth while - Steve Webb might be able to give a little more info on that..

Fiat Tipo 2.0 16v 5 door\thema 2.0 16v inlet cam will also give an extra 500rpm at the top end which will be good if you are running the larger turbo.

For anything about 1.3 bar I'd recommend getting hold of a grp N head gasket & some ARP bolts. Also if you are fitting the inlet cam it might be wise to fit ARP conrod bolts..

The exhaust manifold, down pipe & exhaust system is restrictive & good for quite a few BHP.

The main thing is to get a chip to cover all of the mods you do.


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