beerhead Posted March 7, 2006 Report Posted March 7, 2006 This just shows you how similar the 20V valve head is in terms of valve layout to a Ferrari V12 item. Haven't ever seen an image of one b4, thought someone might be interested. 60V V12 is nice but won't fit in my rolla! Why hasn't toyota made a 40V 3.2L V8 damn it, imagine that, anyone got a thick checkbook :wink: Ferrari Quote
Tiger Posted March 7, 2006 Report Posted March 7, 2006 How about that, huh? VERY interesting. I think the 20V head looks abit better... needs about 4 more sets of 5 x valves on the head... but yeah... personal loan required :wink: Quote
Teddy Posted March 7, 2006 Report Posted March 7, 2006 Ferrari has a 60V V12 ? *teddy just melted onto the desk* Quote
love ke70 Posted March 7, 2006 Report Posted March 7, 2006 they are very similar, but i don't think there is alot of room to get creative when you are squeezing five valves into one combustion chamber :wink: Quote
Biggo Posted March 7, 2006 Report Posted March 7, 2006 Anyone noticed that the 20v has slightly bigger exhaust valves? Well it looks like it to me... I wonder what it means in terms of performance vs all the same sized ones? Quote
Teddy Posted March 7, 2006 Report Posted March 7, 2006 This is how i look at it ! - may not be proven / correct / total crap :wink: The way i look at it, you have 5 ports. As i have no experience in port air flow terminology, ill just make up numbers as an example. (CFM.. is that the term they use?) 5 ports - 3 intake, 2 exhaust - all the same size? If you have 5 ports, all the same size, each port flows 100 CFM. Intake totals 300 CFM, where as exhaust totals 200 CFM. Now, going by most theory's out there, the motor doesn't push the exhaust gases out on the exhaust stroke, but 'vacuumed' out, by the vacuum created in the section of 4 gas exhaust pulse's - that stroke being one. (hope that made sense?) - Now, if you have 300 CFM of intake gas being 'vacuumed' out of the cylinder, through 200 CFM's area of exhaust porting, isn't that going to create airspeed in the exhaust, in a compressed way possibly creating excessive back-pressure? In the 20V head (Toyota) - the 3 intake valves are smaller than that of the exhaust ports. Take a 16v 4age for example. They get there power from reving. Why, because the ports are small, (small ports, ported the correct way, creates air speed boys and girls - not big ports :y:) and there is 2 of them. Lots of air fuel mixture into the cylinders is good mmm k ? With that said, Toyota has gone "mmm... lets add 1 more to the party" - make the valves slightly smaller, but add 1 more, and you can get even more volumetric efficiency into the cylinder per stroke & use up more physical space on the cylinder head - which in it self, theoretically is a good design. From the motors ive seen, the exhaust valve is always larger than the intake valve. Get the TRD Brothers onto this topic.. thats as far as my brain can go, on 1st year apprentice wages. :y: Oh, and btw, please, someone tell me if I'm headed in the wrong direction with most of that.. as its a miss or possibly hit the outer edge topic for me atm ! Quote
Toycrash Posted March 7, 2006 Report Posted March 7, 2006 This just shows you how similar the 20V valve head is in terms of valve layout to a Ferrari V12 item. How many different ways is there to fit 5 valves in head? Most 20valves look exactly the same. But i would love to see how ferrari made their intake and exhaust PORTS... Quote
Biggo Posted March 7, 2006 Report Posted March 7, 2006 Teddy - thats makes a bit of sense (to me atleast... You noobs might need help) But don't forget Bigger ports = more air flow as opposed to air speed :wink: Quote
Teddy Posted March 7, 2006 Report Posted March 7, 2006 (edited) Yes, Bigger ports means more air flow, - i was saying that in a selected context, but i know that you know that i know where it were it was coming from *rofl* Bigger ports + standard valve = more air flow = more volumetric efficency (if ported corectly) = more air speed. Big ports + Big valves + not ported to create air speed = can slow the air down. Edited March 7, 2006 by Teddy Quote
love ke70 Posted March 7, 2006 Report Posted March 7, 2006 bigger valves in a 20 valve head also results in a reduced squish area doesnt it? which means more area of 2 valves are sucking on the same air, which isnt too good. Quote
Dimitri Posted March 21, 2006 Report Posted March 21, 2006 its hard to tell but it looks like the ferrari is running more squish beside the exhaust ports. also ferrari don't use 5v/cylinder anymore do they? Quote
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