ALFAGTV6.COM

SydneyJules · Post by **SydneyJules** » Thu Feb 07, 2008 1:21 am

But then again, Greg, isn't the whole point of going down that path so you can throw more boost/revs at it and make more!?!?!!!!

I would be going down that route with a Nord or TS, but yourself and GTV6GPTT have done a fine job on stock internals- 12-15psi in a well tuned V6 should be plenty- and probably just under the "break the transaxle with your right foot" threshold.

It's almost worth the extra weight over the front wheels for all that torque....

GPTTs car pulls the long ratio's easily.... then again, I'm sure your 75 does a fine job of it too.

Ahh I need a better job!

Burger · Post by **Burger** » Sun Mar 16, 2008 4:34 pm

Read on alfabb that 5 year is now swapping in a G.M. powerplant and supercharging it.Man,just rebuild your stocker!

GarthW · Post by **GarthW** » Wed Mar 19, 2008 10:16 pm

Nah Jules just save for a new snail, cooler and bits, if you can do most fabrication stuff yourself, you will save alot. I spent hours fitting the cooler, making sure everything would fit, work etc.
I've saved at least over 2grand in labour, and more to come.
I've saved alot more money going forced than i would have if i went n/a.
A hot N/a setup would have cost me like over 6-7grand easy i believe.

How long will a standard 2.5 last with stock internals running 12-15psi?
2-3 yrs..? Still a great achievement though damn.

Cant wait to boost a 24v 2.5 quad cam soon, will be insane.

SydneyJules · Post by **SydneyJules** » Mon Mar 24, 2008 5:21 pm

Very true garth- but now i have body issues to sort out... as well as flying stuff to pay for!

But I cant see any reason a stock internalled 2.5 wouldn't last forever under 15psi boost- as long as you where nice to it!

Hot na setups are great for not breaking things and engine bay space, but horrible for the bank!

GarthW · Post by **GarthW** » Thu Mar 27, 2008 12:38 am

My god if i knew a stock 2.5 would handle 15psi forever i wouldnt have bought forged pistons!

But then my turbo is made to run 20, so hopefully they will prove their worth then lol. Thats once driveline is beefed up too of course

sh0rtlife · Post by **sh0rtlife** » Thu Mar 27, 2008 1:35 am

you guys are kidding me about the 2.5 handleing 15psi without issue right?!?!?!?....and what do you mean by "being nice"....no driveing like ya stole it?....thats the fun part

Greg Gordon · Post by **Greg Gordon** » Thu Mar 27, 2008 10:50 am

I probably wouldn't put 15psi through a stock 2.5, although I agree it could hold together if everything went well, you had no detonation, and you were careful.

Forged pistons get you a larger margin of safety. They are less likely to be damaged by detonation, and if they do suffer damage from detonation it won't be as catastrophic.

Greg

GarthW · Post by **GarthW** » Fri Mar 28, 2008 1:17 am

Ah thankyou Greg, feeling much better about my purchase now!

SydneyJules · Post by **SydneyJules** » Thu Apr 03, 2008 1:50 am

Yeah OK a bit optimistic on that one then!

Duk · Post by **Duk** » Thu Apr 03, 2008 6:49 pm

Just as an example, there is a guy on a Toyota forum (Toymods) I'm a member of that pumps 20psi into a standard, 10:1 compression ratio, Toyota 1UZFE 4ltr quad cam V8. It pumps out nearly 400KW at the wheels running 98 octane pump fuel, water injection, a big intercooler and 2 turbo's that aren't overworked. An impressive achievement and a great example of what having excellent control of your engine can produce.

kevin · Post by **kevin** » Fri Apr 04, 2008 11:20 am

Garth, great project there. Let see some more pics.

GarthW · Post by **GarthW** » Sat Apr 05, 2008 2:43 am

Thanks Kevin, more coming.
I must say i've been keeping an eye on what these guys are doing with toyota engines. 1800HP from a 2JZ!!

OK, back to Alfa stuff!!

Greg Gordon · Post by **Greg Gordon** » Sat Apr 05, 2008 1:45 pm

Duk, that's a good example of what can be done with a good setup. It's no longer unusual to see people running huge amounts of boost with higher compression engines. However in most cases they have seriously retarded ignition timing and would probably make more power with a little less compression and more timing (unless the forced induction system is near it's practical limit). Keep in mind many of these later engines have knock sensors that have been well developed by the factory so they can run things closer to the edge than those of use with older design mechanical valve trains.

I watch the Cobra and 2JZ stuff pretty closely. It's quite common to see 03'-04' Cobras with 25 psi and all stock internals. Toyota's 2JZ engine is remarkable. Those engines and a lot of other Japanese engines are supported by a lot of factory development and a huge amount of aftermarket development.

As impressive as all this newer stuff is, I think it's important to look to the past as well. Alfa got 450hp from a 1.5 liter supercharged engine in 1959!

Greg Gordon,
www.hiperformancestore.com

Duk · Post by **Duk** » Sat Apr 05, 2008 5:04 pm

Hi Greg.
The car in question uses an after market computer, Autronic from memory, so no factory knock sensing.
I can't comment with any authority about the engines ignition mapping, but the car has been running for years, getting the crap caned out of it and it's still going strong with no reported high exhaust gas temp related failures like cracked (fabricated) manifolds or burnt valves.
Deffinately in this guys favour is the cost of such an engine. If he every blew it up, another wrecker special engine isn't exactly expensive ($less than $1200AU).
Kind of frustrating that of my 3 cars, the Alfa is the slowest, most expensive to get more power out of and would cost the most to replace/rebuild the engine if/when it needs to be

PS. Honda exceded 1000HP by the end of the turbo era of Formula 1 and had the best record for reliability also from a 1.5ltr engine

Greg Gordon · Post by **Greg Gordon** » Sat Apr 05, 2008 6:47 pm

I'll bet it does have factory knock sensing. Like most engine management systems Autronic will retard the timing when knock is sensed, but the sensing is almost certainly done by the factory equipment, and that's the hard part to work out (type, location, sensitivity, etc.). I don't think Autronic even makes a knock sensor.

Making that work on a 2 valve per cylinder Alfa engine is problematic at best. Not even Jim Steck has been able to do it.

I certainly agree about the economic advantage of building up a Japanese engine. Most Japanese engines are relatively easily and economically replaced. I was recently at a shop that specializes in Japanese performance and they commented that when the blow engines they don't even bother to take them apart, they just plug in another low mileage JDM unit.

Overall my point here (and I think we are in agreement...) is that getting 20psi into a good late model Japanese engine with stock internal components is not that unusual anymore. However to do this reliably with an Alfa V6 you will need internal engine mods, and they won't be trivial. Forged pistons are a good place to start.

Greg

GM?