Discussion
Oh poo, why did we have to lose the thread on the purple pipes. It was the best, most informative, and possible the most interesting thread I've read on the Cerb forum in months.
Okay, it got a little heated in places but I'm sure most of us reading the comments are well used to the idiosyncrasies of the major players on the thread and were willing to look past it to learn.
So here I go to try and understand this. Does anyone know home many degrees of crankshaft rotation the inlet valve on a 4.5 Cerb is open for?
If we have this information we could THEORETICALLY work an optimal tuned length.
Okay, it got a little heated in places but I'm sure most of us reading the comments are well used to the idiosyncrasies of the major players on the thread and were willing to look past it to learn.
So here I go to try and understand this. Does anyone know home many degrees of crankshaft rotation the inlet valve on a 4.5 Cerb is open for?
If we have this information we could THEORETICALLY work an optimal tuned length.
It was my fault .. many apologies for ruining carbon al's glory by getting all heated.
the pipes did look stunning.
I got *told off* (like being back at school again
) for pushing the point too hard about showing where the power came from.
It was as you said by far the best thread on the cerbera forum for bloody ages and it really pisses me off that you can't say what you want in front of the amassed crowd, but like i said to Ted .. i fully appreciate his right to tell me to shut up on his forums if i upset people. It's his bat and his ball after all.
No apologies though except to carbon al and Ted, i stand by everything i said.
Now then, back to proper cerbera topics .. are yellow ones really the best???
incidently, i got just over 350hp at the wheels on a car today and had very low rolling losses, but I admit that I cheated .. i ran it in third gear just to see what graph it would give
the pipes did look stunning.
I got *told off* (like being back at school again
) for pushing the point too hard about showing where the power came from. It was as you said by far the best thread on the cerbera forum for bloody ages and it really pisses me off that you can't say what you want in front of the amassed crowd, but like i said to Ted .. i fully appreciate his right to tell me to shut up on his forums if i upset people. It's his bat and his ball after all.
No apologies though except to carbon al and Ted, i stand by everything i said.
Now then, back to proper cerbera topics .. are yellow ones really the best???
incidently, i got just over 350hp at the wheels on a car today and had very low rolling losses, but I admit that I cheated .. i ran it in third gear just to see what graph it would give
joospeed said:
how come you posted on my thread but I can't see what you've posted Jools. Come on rotation???
erm i can see it ..
rotationrotationrotationrotationrotationrotationrotationrotationrotationrotationrotationrotationrotationrotationrotationrotationrotationrotationrotationrotationrotationrotationrotationrotation
The number of degrees of crankshaft rotation that the inlet valve is open for in every 720 degree cycle.
The camshaft dictates the inlet valve opening time and therefore dictates the pulse pressure wave created.
So I need to know the valve opening time in relation to the cycle
>> Edited by Julian64 on Thursday 19th May 20:05
The camshaft dictates the inlet valve opening time and therefore dictates the pulse pressure wave created.
So I need to know the valve opening time in relation to the cycle
>> Edited by Julian64 on Thursday 19th May 20:05
Well pretty theoretical seeing as I don't have a rolling road in my garage.
The greatest deceleration of the valve is at closing or opening, and therefore the pulse wave should be created at this point regardless shouldn't it?
Humour me here. I'm searching everywhere for the cam profile and therefore angle of opening?
Shoot me down in flames once I've actually got airbourne why don't ya
>> Edited by Julian64 on Thursday 19th May 20:15
The greatest deceleration of the valve is at closing or opening, and therefore the pulse wave should be created at this point regardless shouldn't it?
Humour me here. I'm searching everywhere for the cam profile and therefore angle of opening?
Shoot me down in flames once I've actually got airbourne why don't ya
>> Edited by Julian64 on Thursday 19th May 20:15
there's 5 cam profiles that i know of, though i think only two made it onto production cars.
there's a guy on PH who's an engine tester and has a lot of camshaft experience .. time to bring an expert in to answer this one i think .. cams aren't my bag so i can't bring much to the topic i'm afraid.
there's a guy on PH who's an engine tester and has a lot of camshaft experience .. time to bring an expert in to answer this one i think .. cams aren't my bag so i can't bring much to the topic i'm afraid.
Trouble is my question is very specific to the AJP8 and not general to a cam designer.
I'm trying to theoretically work out the path and timing of the pulse pressure wave created at the trumpets of the Cerb.
Obviously this is related to the cam profile and the particular rev range your trying to improve. Assume for a second I'm trying for the magic 400+ bhp at the expense of everything else.
For quite some time I have made intake pipes for model ram jet engines. I'm just wondering how close the calculations get to each other.
But to go any further I need rotation info. It should be easy to get if your doing an AJP8 tappets. How many degrees does the crankshaft turn between the inlet valve starting to open to the time it closes.
If nobody has this info I'm gonna start taking my car apart.
>> Edited by Julian64 on Thursday 19th May 20:34
I'm trying to theoretically work out the path and timing of the pulse pressure wave created at the trumpets of the Cerb.
Obviously this is related to the cam profile and the particular rev range your trying to improve. Assume for a second I'm trying for the magic 400+ bhp at the expense of everything else.
For quite some time I have made intake pipes for model ram jet engines. I'm just wondering how close the calculations get to each other.
But to go any further I need rotation info. It should be easy to get if your doing an AJP8 tappets. How many degrees does the crankshaft turn between the inlet valve starting to open to the time it closes.
If nobody has this info I'm gonna start taking my car apart.
>> Edited by Julian64 on Thursday 19th May 20:34
I'm a cam guru!
Bloody easy making cams up for a blowed engine...
but anyway, more seriously,
getting as much air in at the fastest velocity with some well harmonised turbulence and the splash a dose of well atomised fuel into the stream and you've got a killer.
so again, I raise the point, why not just throw the lot away and put a straight BIG rectangular pipe coming off the throttlebodies and straight out with a single K&N panel filter element.... I mean if it works for mega-high-compression NA Nascars, then its gotta work for the cerbies....
Stop fiddling with whats there, and start from scratch. A set of well polished unrestrictive throttlebodies and a solid aluminium intake manifold gasket is definitely where you need to start, and then use carbon or aluminium sheeting, whatever scratches your nuts to package it all up for a good price to the masses.... plus if you do a little A-R-T it can look better than standard, which is another BIG selling point....
Bloody easy making cams up for a blowed engine...
but anyway, more seriously,
getting as much air in at the fastest velocity with some well harmonised turbulence and the splash a dose of well atomised fuel into the stream and you've got a killer.
so again, I raise the point, why not just throw the lot away and put a straight BIG rectangular pipe coming off the throttlebodies and straight out with a single K&N panel filter element.... I mean if it works for mega-high-compression NA Nascars, then its gotta work for the cerbies....
Stop fiddling with whats there, and start from scratch. A set of well polished unrestrictive throttlebodies and a solid aluminium intake manifold gasket is definitely where you need to start, and then use carbon or aluminium sheeting, whatever scratches your nuts to package it all up for a good price to the masses.... plus if you do a little A-R-T it can look better than standard, which is another BIG selling point....
S-X-S said:
I'm a cam guru!
Bloody easy making cams up for a blowed engine...
but anyway, more seriously,
getting as much air in at the fastest velocity with some well harmonised turbulence and the splash a dose of well atomised fuel into the stream and you've got a killer.
so again, I raise the point, why not just throw the lot away and put a straight BIG rectangular pipe coming off the throttlebodies and straight out with a single K&N panel filter element.... I mean if it works for mega-high-compression NA Nascars, then its gotta work for the cerbies....
Stop fiddling with whats there, and start from scratch. A set of well polished unrestrictive throttlebodies and a solid aluminium intake manifold gasket is definitely where you need to start, and then use carbon or aluminium sheeting, whatever scratches your nuts to package it all up for a good price to the masses.... plus if you do a little A-R-T it can look better than standard, which is another BIG selling point....
stop muscling in on my thread with your dragster nonsense
I wanna sort what I got not chuck it away and start again.
Pick up that bent camshaft you got on the floor ash and measure it for me.
joospeed said:
It was my fault .. many apologies for ruining carbon al's glory by getting all heated.
Now then, back to proper cerbera topics .. are yellow ones really the best???
Hey Joolz....nothing wrong with those threads......
At least they stay light hearted
and create some healthy banter....... All innocent fun......and not in ANY way techy...
.....but a laugh just the same..... 
YP Okay...I'll mess off back to the Sagaris Forum now.....
lol, how'd you know its bent???? is this topic livecam or soming???? eeeeek
hehe
my point was, those office plumbing big black hoses and fake carbon boxes and blue-peter throttlebodies need to be thrown away, and back to basics old school ram box the air in without changing the flow path, also use 270degree funnel trump's on the TB's, similar to the old Ferrari V12's.... also, you can possibly substitute the injectors for two injectors per port, one above and one below the plate, of course resistance wired in to halve the load or possibly use a pintle type downstream, and disctype upstream...
Julian, what you want to know about the cams? I've got detailed blueprints and technical specifications here, not for the general public, but any peice of info you need, email me.
hehe
my point was, those office plumbing big black hoses and fake carbon boxes and blue-peter throttlebodies need to be thrown away, and back to basics old school ram box the air in without changing the flow path, also use 270degree funnel trump's on the TB's, similar to the old Ferrari V12's.... also, you can possibly substitute the injectors for two injectors per port, one above and one below the plate, of course resistance wired in to halve the load or possibly use a pintle type downstream, and disctype upstream...
Julian, what you want to know about the cams? I've got detailed blueprints and technical specifications here, not for the general public, but any peice of info you need, email me.
yellow peril said:
nothing wrong with those threads......
At least they stay light hearted
True, but when my mates notice a page left open on the laptop once, they pissed themselves laughing... its kinda wierd with things like 'the yellow meet' and 'the yellow cruise' and 'the yellow bash'....
Yeah, its all good fun... but it would be great if we actually had severe technical discussions in here, where all the tuners and engineers could just debate things.... maybe a special forum that only engineers have access to could be set-up by Ted, and all the techies (licensed) get access to it? Ted you'll need security, so I'll watch the doors in that one
Julian64 said:
I'm sorry but anyone who chooses a saggy arse in preference to the work of art that is a Cerbera
SHOULD NOT BE MUSCLING IN ON MY THREAD.
I own this thread. The next poster better be able to give a correct angle. Or I want this thread to die.
Oops...
So there should be a new rule, whoever is the owner of the thread, should be able to delete posts of other users as they wish... Ted? What you think?
S-X-S said:
Julian, what you want to know about the cams? I've got detailed blueprints and technical specifications here, not for the general public, but any peice of info you need, email me.
The ROTATIONAL angle and therefore the time in any one crankshaft cycle that the valve is open.
Sorry, if I didn't make that CLEAR earlier.
Now, I may have to kill you if you open up another make it more like my dragster reply.
>> Edited by Julian64 on Thursday 19th May 20:59
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