i've been reading about these and i'm alittle confused
wat exactly do they mean by vtec killer toda cams? is that like running high cam 24/7?
also with spec A B and C, after installation does the rev limit rise or soemting?１
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i've been reading about these and i'm alittle confused
wat exactly do they mean by vtec killer toda cams? is that like running high cam 24/7?
also with spec A B and C, after installation does the rev limit rise or soemting?１
yes VTEC killers run on the high lobe only
A, B and C get progressively wilder. You will need to turn your motor tighter to take advantage of the gains they provide
Did I mention that I'm selling my Toda A's??????
Vtec killer cams are without a high cam.Quote:
Originally Posted by kiddoDC2
It is not like running on the high cam at all...
It is the same as running a non Vtec dohc engine, as this is what the engine becomes. It is done for reliability at extreem rpm.
(That is, one cam lobe per rocker arm, per valve. No central lobe, no centre rocker, no vtec solinoid, no vtec mechanism, no lost motion devices, no oil pressure fluctuation)
The rev limit of an engine is an engine management function. The camshafts selected has no bearing on this. Though using a TODA camshaft would allow you to extend your usable rpm range it would not give you the ability to actually do it. that is change the actual rpm limit.
Why would someone buy VTEC killer cams for a VTEC? Apart from your mentioned reliability at higher RPM's, wouldn't that defeat the purpose of VTEC?
You'd be better off building a DOHC non-VTEC if you wanted to go N/A right or am i missing the point...?
:?
how much usable rev range is there from the A and B cams?
i heard somewhere that C is someting like 10,500 rpms?
Id say u can make power to 10500 on the Cs however its not as simple as just whackin in these cams.They are pretty wild and you will need to upgrade your valve springs,retainers, oil pump gear etc.. Wouldnt really want to rev to 10,500 with stock rods either.. Also intake manifold, TB, ecu,bigger exhaust etc would all need to be done to make power that far.Quote:
Originally Posted by kiddoDC2
I think i know where u got the above idea from..some other thread recently posted here..the person who posted that also said that with C's VTEC engages at 8000 rpm...which is false :roll: :roll:, with the Toda Cs ull be making about the same power on your low lobe as your car already makes on its high lobe. I dont know what car you have but if your looking at something mild and not over the top where u have to modify alot of other components id suggest going for ALLMTRs Toda As or if u have a vtir of some sort maybe an upgrade to just some TYpe R cams..
vti-2: Possibly turbo applications.
Sorry guys... Better get a coffee... This is a long one...
I appologise for the post whorishness...
Cheers
vti-2 - Vtec killer camshafts were originally designed for N+ racing applications where Vtec is banned... In any case it has drifted into other forms of motor sport because of its benefits...
The benefit of the DOHC Vtec engine is not only the Vtec it possesses for the street but the engine as a whole...
The rod ratio is more ideal than other comparable engines. The cylinder head is a great starting point. The block is very good & some of the factory crankshafts are just excellent...
Obviously this doesn't relate well to road engines but there are a variety of applications where losing the Vtec is a good thing...
Example, a circuit car needn't use Vtec, nor a drag car...
The fastest of Honda drag machines do not use Vtec... both NA & turbocharged... this is not to say they use small cam profiles. On the contrary they use very aggressive camshafts.
Trying to get your head around this or that camshaft is difficult enough for the average punter. When people who don't know sprout off on the Internet, more mud is added to the already clouded waters of people's minds...
Fact is they work; there is an application for them. They are not suitable for street use, as a Vtec camshaft will deliver superior results on the street.
kiddoDC2 - The useable rev range of any camshaft is application dependant. Furthermore it is set-up dependant. Should you have a mixed & matched set-up as most do... You will not achieve the power you could nor will you make it at extreme rpm.
To get large cams working well at high rpm is a lot more involved than simply putting them in.
A lot of time and effort must go into the cylinder head to achieve power at 10,000+rpm... This is just 1 aspect...
Havok - what you're saying is basically correct... Cheers...
Regarding revs & Vtec swap etc...
B16A turbo application with Spec C's we swapped at around 8000rpm...
B18C NA application, we swapped the Spec B's at 6700rpm...
K20A NA application, we swap the spec A's at 3,900rpm...
F20C Supercharged application, the stock cam is swapped at 4,400rpm...
F20C Turbo application, the stock cam is swapped at 4,800rpm...
F20C NA application, the Spec A cams are swapped at 4,500rpm...
This is in these particular applications...
Each engine is different; there is no pattern... Each combination is different...
Examples (re above engines)
The turbo B16 engine is this case could be revved to 11,500rpm...
Rpm limit was set to 10,500rpm, peak power was 326kw @ wheels...
Peak power arrived at 10,000rpm...
9.4:1 CR + lots of goodies
The NA B18c engine in this case is limited to 9,400rpm...
Peak power of 146kw arrived at 8,800rpm... 118kw was achieved on the low cam... 12.4:1 CR (all TODA parts)
For a road engine, Spec A's are excellent if you're on a tight budget...
If you're serious about performance you'll go bigger & use B's or C's...
Don't make the mistake of wanting C's because they are the biggest...
It doesn't work like that...
Guys... You have to realise combination is everything...
Mixing & match without experience doesn't work...
Ok... I'm off the soapbox now...
Cheers
So if i wanted to keep the car as my daily driver but with more power I'd go for A's or B's because the C's would be overly aggresive ?
Or am i reading this wrong ?
-2ds
It’s not that you’re reading it wrong…Quote:
Originally Posted by 2ds
Cam selection isn’t as simple as some people would have you believe…
In truth, cam selection is dependant upon set-up, application & engine type / configuration… There is more to cam selection than simply lift & duration figures…
Lobe centre angles (LCA’s) play a vary big part in it too…
Other misconceptions are that the idle will somehow become awful using large Vtec camshafts. This is not the case at all…
Though the idle is noticeably more solid, it is in no way unacceptable or rough.
Re: Spec B & C
Other areas often overlooked is the set-up required to maximise certain camshafts…
What sort of exhaust system you really need rather than what you think you want…
Which headers really work vs. popular cheapies that only offer gains on engines that are scarcely modified…
ECU selection… This will make or break the whole package…
Who tunes it? Not all tuners are equal…
The amount of effort needs to go into your cylinder head…
The list goes on…
On top of that, the greatest conundrum of all… Who do you believe?
Some answers to the above questions are under your nose...
Others aren't what you might expect...
i recently went from 4-2-1 to a 4-1 header and i also installed an ITR intake manifold with TB. and on the dyno it made power past 8,600 with stock cams. This is for a B16A.
So the setup of your car will determine how high up your cams will make power.
we also fiddled around with the VTEC x-over and suprise suprise. The stock x-over point was the best
hmmm, so I can probably raise the redline another 1000rpm at least on stock cams. thanks weezer =)
-2ds
Using stock cams will limit you to very minimal power gains.
The same can be said for OEM engine management systems...
2ds - Without any internal changes to the engine, increasing your rpm limit is a good way to drive over your engine.
toda:
Man I'm not _that_ ignorant, changing cams is pretty major as opposed to putting a new exhaust on though.
-2ds
im just saying it made power up that high with the proper setup. I wouldnt rev it that high on the road. ive set the rev limit pretty close to stock because my engine is still internally stock. and yes. engine management is very important
don't you dare make a post about valve springs toda =)
-2ds
?
gonna steal this thread
im thinking of doing cams valve springs etc...head work
do you think that it is wise or worthwhile on a B18C that has done 190,000 ??
am i wasting money or you see this as worthwhile ?