As I recently saw my engine (stock 3.0 12v) starting to oil burn, I'm thinking about the future and what's the best option to go for.
I know rebuilding it with 10.5:1 pistons (where to buy?), CB cams, ported heads, bigger intake valves, CSC headers, bigger runners and plennum, larger AFM & Megasquirt sounds kinda porn , but too pricey, and I guess it would had about the same HP as a stock 24v, wouldn't it?
I'm not in a hurry, but I'd like to know what's the best option for the buck.
hi jose,the best hp for the money is THE SUPERCHARGER!
you'll have a lot more torque AND hp.
if you rebuilt your engine with VERY expensive parts ,MAYBE you will have some 20 real hp gain,but no extra torque!!
the supercharged and with standard internals gtv6 will beat the crap out of you!!!!
for about 2500$ (i think) you'll have yourself a monster!!
i can bet!
Yep, you're damn right, but I can't fit a supercharger or the TÜV guys will arrest me!
I should make it look as standard as possible. I could see a picture of LENZ's 24v conversion on his 75, that looks extremely clean and like it was stock, but couldn't contact him to ask
you guys have Tüv in tenerifa????
i think here they won't even notice it!!!
as long as your tires are not worn or holes in the chassis,or steering failures....they'll see NOTHING!!
when they see my car they think i made it myself!!!
i'll pass always,there is no standard for this car.hahahaha
stupid tüv guys
Get Greg's Blower kit, and rebuild your engine with 9:1 pistons so you can put some worthwhile boost into it.
With an intercooler and management, 12-15psi of boost could go into it on 98 octane fuel, maybe around 12-psi tops on 96 octane, with less aggressive ignition, and straight away you're talking at least 350 flywheel HP, not to mention the torque....
The 24v stuff is all pretty horn, and you can count on around 270hp flywheel from a stocker with management, but where will you go from there?
Blower kit on the other hand, leaves you with a host of little things to do down the track, that will give more rewarding increases in HP and torque- starting with extractors and an exhaust, moving to cams, porting, HPC Coating- 400hp is there for the taking, and all of a suddne, the only probem will be your diff! If you go naturally aspirated, you can basically make a bigger engine, or rev it harder.... I may have a naturally aspirated engine, and Im a big fan of it, but right now, Im looking for ways to make it bigger, simply beccause there is no way I can go about more HP!
If I had gone turbo four at the start, I would have more torque and HP, and would simply be turning up the boost as I go!
I know power and torque gains with turbos are bigger, but I just can't do that or I could get in trouble with the authorities . on the other hand, the aspirated sounds far better .
I'd go for 220-250HP, that would be enough for me. That's why I want to know what's the best option between the two engines.
hi jose,the 24V will give you with only squdra chip 250 hp!! with all the modifications necessary for installing this engine :brakebooster,headers,injectionsystem $$$$$$$$,................
you already have a 12V fitted in your car.
if you take it apart and have a 3,5 linerset,you'll have about 230 hp,take some nice cams maybe some flowing and different valves and you'll probably have 250 real hp!!
maybe just buy a porsche???
rz – not true on the “…maybe 20 hp gain with a rebuild using very expensive parts…” comment… rebuilding with forged aluminium alloy pistons etc gets that little 2.5 154 horse motor up to 280 with about 10.7:1 compression ratio… (Far from “maybe 20 horses”…) And as for torque – these things become low-end monsters!
I don't know... Reading this, I just can't help but respond... I am VERY fortunate to have been able to drive twin turbo 12 valves, twin turbo 24 valves, naturally aspirated 12 valvers and 24 valvers in 3.2, 3.3, 3.45 and in 3.7 litres...
Keep I mind though; you don’t just “throw-in” a set of high-compression pistons real quick…Bang for the buck - you can't beat the 12 valve 3.45 for 7-8-9K USD... Next up; the 3.45 24 valve in the 8-9-10K range is even more amazing! (The best value if so it be called...)
From a cost stand-point: I just bought the 24 valves, new valve guides, new valve stem seals and an OEM gasket set today with new tensioner pulley and new belt for my street 24 valve 164... 2500 USD - JUST FOR THE PARTS!
Here is TRULY your cheapest conversion: Stock standard 24 valve 3.0. Take the rods out and have a machine-shop push open the small end by .5mm (up…) KEEP the 3.0 pistons but machine them down just a hair. With the compression now up to a healthy 10.5:1 or so, just add Dawie’s Group 1 cams: 208 horses at the wheels AT 6000 FOOT ELEVATION!!!! (That’s more than the 3.2 litre 147 GTA race cars make with full electronics, open exhaust and 7500 rpm limiter on that same dyno!!!) Stock 164 Q makes 156 on that dyno!
You CAN NOT just simply bolt-on an SC or Turbos to the stock sub-assembly, crank up the boost and rev it all to hell and expect good results. Low-low boost, yea fine, but don't expect more than 220 to 230 horses from the 12 valve.
24 valve with a chip and good exhaust takes you to 250 already, yes, but with nowhere near the torque off the built 3.45 12 valve... And the built 3.45 12 v hits 280 horses like a dream! (And now you have the option to build it with the correct level of compression and do turbos the right way.) 3.45 24 valve hits 300...
...to Alfa, or not to Alfa? That is the question...
Yeah, basically you "lengthen" the rod by pressing the top bushing out and then cutting open the inside of the small end (the inside of the opening at the top) and filling in the bottom of the opening at the bottom and then pressing in a new bushing...
This places the wrist-pin holding the piston higher (and by extension the piston itself) by .5 of a mm...
Sorry, no drawings. To compensate for the higher piston position, the pistons are machined down a hair to ensure valve clearance.
The cams; he can do pretty much anything, but he seems to favor his Group 1 profile that he uses a great deal on several different engines! Not too lumpy - very smooth at idle, huge torque way down low and fantastic power up top...
As far as contacting Dawie, sorry no website - I have launched www.glenwoodalfa.com to help him with his marketing a bit... Please contact me there for pricing on his products...
...to Alfa, or not to Alfa? That is the question...
junglejustice wrote:
Here is TRULY your cheapest conversion: Stock standard 24 valve 3.0. Take the rods out and have a machine-shop push open the small end by .5mm (up…) KEEP the 3.0 pistons but machine them down just a hair. With the compression now up to a healthy 10.5:1 or so, just add Dawie’s Group 1 cams: 208 horses at the wheels AT 6000 FOOT ELEVATION!!!! (That’s more than the 3.2 litre 147 GTA race cars make with full electronics, open exhaust and 7500 rpm limiter on that same dyno!!!) Stock 164 Q makes 156 on that dyno!
Yes, we've heard about this - and I do know that Dawie's dyno doesn't lie. This is truly something, considering the 147GTA cars (also built by Dawie) hit only 204bhp.
What causes this? smaller stroke and lighter pistons? (and hence obviously less torque on the motor but with more top end power?
What causes the increase, is the raised compression in the engine, and the increased squish band that occurs. Now the piston is protuding slightly more in the liner, and therefore further into the combustion chamber.
But, the biggest gains come from the cams, as the 147 race cars have to run 'production spec' and use standard gta cams.
Jose_76
You could also try as a cheaper alternative, skimming the 24v head by 1mm, to up cr to 11.1:1 and run some glenwood cams, or C&B fast road (very very good), Saves on the rod work, and piston machining - not cheap. Results are very similar.
Hamishm00 wrote:
junglejustice wrote:
Here is TRULY your cheapest conversion: Stock standard 24 valve 3.0. Take the rods out and have a machine-shop push open the small end by .5mm (up…) KEEP the 3.0 pistons but machine them down just a hair. With the compression now up to a healthy 10.5:1 or so, just add Dawie’s Group 1 cams: 208 horses at the wheels AT 6000 FOOT ELEVATION!!!! (That’s more than the 3.2 litre 147 GTA race cars make with full electronics, open exhaust and 7500 rpm limiter on that same dyno!!!) Stock 164 Q makes 156 on that dyno!
Yes, we've heard about this - and I do know that Dawie's dyno doesn't lie. This is truly something, considering the 147GTA cars (also built by Dawie) hit only 204bhp.
What causes this? smaller stroke and lighter pistons? (and hence obviously less torque on the motor but with more top end power?
Yeah, but I don't like taking meat off of heads unless I NEED to...
Never know when you are going to need that margin down the line... (like when you overheat, warp heads or loose a head-gascket and then you're screwed....)
...to Alfa, or not to Alfa? That is the question...
, but too pricey, and I guess it would had about the same HP as a stock 24v, wouldn't it?
. on the other hand, the aspirated sounds far better 
