V8, V10, V12

[T-Bird]

OK just for basics to try this thing out Ford 427, 4 valve V8 Methane Turbo at 30psi
and a 36 degree overlap, intake 2.0 and exhaust 1.6 compression ratio 11.5:1
hydraulic lifters, racing cam (if available) you can do the little stuff if anything doesn't quite mesh well
WTF throw in a 200 shot of nitrous just for kicks

[fedezyl]

MMmm interesting! so if I gave you some info you could see wich modifications make more power....cause i'm looking to modificate my alfa's engine, it's a 1.3 4 pot 8 Valve twin cam, it makes 82 bhp stock, and 105bhp I think with twin webber carbs...

[T-Bird]

your car is carburated? what year is it?

[RC45]

T-bird - what brand and model turbo? Fuelie or carb? And what sort of CFM you thinking about? Intercooled?

And you want a drag race cam profile or a streetable/road course bump stick?

[T-Bird]

ok Garrett GTP38R turbo with dual 800CFM Holley 4 barrel carbs

[fedezyl]

the 1.3 liter engine in the Giulia Ti comes with a single double opening (don't know the name in english) Solex carburator, on the Giulia Super it comes with a twin double opening webber carbs

[T-Bird]

I think you mean a 2 barrel(the openings) Carb

[fedezyl]

hehe yeah, barrel that's the word! english improves everyday hehe
now...there's something I never really quite got straight, how does the size of the carb changes the powerband, as well as size of the jets? I remember reading something about it but never got it quite clear in my head....

[T-Bird]

do you mean the like the overall power curve or just the top HP number?
It all has to do with the CFM flowing through the Carbs and into the engine the ironic thing is that I have seen people install new carbs and install the largest jets and they make less power than with th enext size down that I never understood myself.
Jets are basically fuel injectors so the bigger the more fuel in essence. and larger Barrels means more air it's that simple but sometimes like in your case you may have to change out the intake manifold to fit the larger carbs but that's a case by case thing but I would recommend replacing an Intake manifold and carbs at the same time. and remember if you are messing with Carbs and your not 100% sure becareful even the pros have lit them on fire before priming them for the first time.

[fedezyl]

heheh, nah, i'm not actually doing the fitting, i'm installing the Super's .40 DCOE webber carbs, it has it's own different intake manifold though so it shouldn't be a problem, it's more like i'm interested in how it works though....and well trying some stuff out, specially like cam settings and compression ratios...also fiddling a little bit with exhaust and intake manifold lenghts too..
oh about the power curve, I meant overall, I came to realizing a while ago that peak power isn't everything and it's best to have a large power band than a typical honda engine that has to be really thrashed....

[T-Bird]

yeah it's nice to have low end torque (as in the bigging of the curve) and HP more towards the top with a nice overlay not like some Turbo cars that are flat till about half way.

[fedezyl]

Thing is I remember having read somewhere on a web site, well actually the web page is from an ex Fiat engineer that worked for Fiat Argentina and he was explaining how different venturi sizes on the carbs gave more low end power than higher and viceversa

[RC45]

How is this for a "simulated" 1.3l Alfa

[ahmedgiyab]

I think that the most HP comes from the V12, but a V8 has more torque......

[sergei_dekker85]

Originally Posted by nejcdolinsek I have a question: Which engine, either a V8, V10 or V12, would produce more power/torque, if all had the same displacement (for instance 5.5l), all had the same amount of valves per cylinder, all were naturally aspired, etc., etc.,...???

I'd take the V12....more cylinders make quite a bit of diff....tts y the FIA decided 2 use V8s instead of the current V10s for F1 in the future....and I've driven a E240(Inline 4) and a 328I(Inline 6) and theres a noticable difference esp in power