Fast Guy said:
RishiGTiR said:
and no i didn't copy this from a book :lol: :lol: :lol: :lol: :lol: :lol: , but thats about the jist of it
deisel weasel said:RishiGTiR said:
going to competely disagree there
an engine is a pump, all it does is pump air, which through the combustion process produces power, with a turbo you are forcing far more air into the engine.
The air can only get into and out of the engine through the valves, no other way. The valve is obviously controlled by the cam, How effectively the air flows that is generated by the turbo is all effected by pipe run, intercooler restriction, inlet manifold design, ports and the valves. On the exhaust side its obviously valves, ports, manifold, then the turbine, before it all f*cks off out the exhaust :lol:
A small turbo with a very long duration, high lift cam would be a complete waste of time as the turbo will not be able to flow enough air at the point the valves would be fully open for it to be beneficial, you'd never create enough air with a small turbo that the engine would be capable of using.
example for simplicity sake: tiny-nob turbos ltd weener turbo : power range 3000-7000rpm, why have a cam setup that would efficiently allow air flow to 10000rpm ?
A big turbo with too short a duration and low lift cam will be physically prevented by the cam set up from flowing the air that the turbo would be able to provide. All you'd end up with is a hideous, laggy, nasty to drive mobile waste of money
example for simplicity sake : humdinger turbos inc : super todger turbo : power range 5000-9000rpm why have a cam set up that would only efficiently allow airflow to 7500rpm ?
On a small turbo you want it spooling at low revs, the small turbine wheel wont require loads of revs to get it going and if, for example, it was possible to rev the engine to say 9000rpm it would be miles out of its efficiency range
On a big turbo if you cant flow the air, you cant produce the exhaust gasses and you cant get the turbo spooling, so with the wrong cam set up you'd never be able to use anyhere near the airflow the turbo could provide, you'd would probably end up with a car slower than you had before
for making the best power possible its all about getting the cam set up spot on to the turbo you are using 8) theres obviously more to it as other factors effect the power an engine will produce but this has been a far to sensible reply from me and my head hurts
some of it might be worded badly
p.s the fact carl is interested in the gtrs puts him right inline for the tiny-nob turbos ltd : weener turbo :lol:
i have doneRishiGTiR said:
its not that simple: , where as a gt30 with a smaller exh housing would be better for the lower rev limit as its going to spool quicker, which would give you a better track, road car 8) , deciding which set up is going to be best for the way you want to use the car. Its reasonably easy for a drag orientated car as you dont need to make any compromises (which is why most of the bigger power cars will be running pretty much the same cam setup) using lots of revs, lots of lift/duration, peaky powerband and no need to worry about idle or low down power/torque, but for track and fast road cars you're trying to get reasonable power and torque with quick spooling response and a nice wide power band, the choice of turbo and cam are directly related to achieving that aim
deisel weasel said:i have doneRishiGTiR said:
for example : if you had a gt30 with 1.06 exh housing that required revs to get it spooling it will perform better on the revver than it ever would on exactly the same size displacement engine that cant carry the revs
But you're then not using the same turbo
You'd have the same turbo/comp wheels, but different housing to match the engines ability to rev, which is directly related to the choice of cams
what i'm trying to say is it isn't just a case of bolting on any old turbo and expecting the engine to work as efficiently, with the power band where you want it and making as much power as it should do :? everything has to be calculated and the combined parts have to work well together,
But like you say, it all depends on what you plan to use the car for 8) which is where it gets hard
exactly 8) which is probably why theres so many people that are unhappy that their car doesn't make the powerRishiGTiR said:
deisel weasel said:p.s can someone say something i can take the p!ss out of now please
nah..wont take you up on that offer thanksRishiGTiR said:
:lol: :lol:
deisel weasel said:nah..wont take you up on that offer thanksRishiGTiR said:
i think i'll just stick around on here in the hope that someone asks what would be the best turbo/cam set up for a car running 1 bar on a bleed valve, on 17's and whether changing the gearbox oil after fitting an safc would have an effect on the chances of them beating every other car on the road when doing laps of their local town centre
Fast Guy said:deisel weasel said:p.s can someone say something i can take the p!ss out of now please
WIll I need a 6inch straight through exhaust for my big turbo, long duration cammed 246bhp engine? (and an FCD of course)
Fast Guy said:WIll I need a 6inch straight through exhaust for my big turbo, long duration cammed 246bhp engine? (and an FCD of course)
:lol: :lol: :lol: price would be the decider for me, the pipers come in at nearly £450 :shock: and thats without pulleysstr_motorsport said:
and they do the same spec, 280, 11.5lift
