K24A3 vs. K20A cams

[integral90]

Does anybody have the exact profile for these 2 engines' cams?

From the research I've done the K20A intake cam seems to have a more aggressive vtec profile but more tame before vtec. Does anyone have any suggestions for a cam swap? I've been told to just swap the K20A intake cam and leave the stock K24A3 exhaust cam.

Any help would be appreciated :)

[EG5]

the k20a intake cams gotta be from k20a2 or jdm k20a.

[integral90]

Yeah, have you found any yet Yonas?? I have cash ready if you do :)

[TODA AU]

Got loads of ém...
You want one?

[bennjamin]

id just like to mention this is for a k24. Give him a proper idea girls :)

[LiL FiLo]

if im not mistaken u just cant put k20a2 cams into a accord euro motor?

wouldnt you have to do a head swap?

k20a2 head will have provision for the third cam lobe. on the k20a2 head both ports are open, once vtec kicks in the valves are opened longer

where as a k24a3 head vtec machanism does not carry a third cam lobe and only opens up a second port when vtec is engaged

please correct me if im wrong but from what i have read, this seems to be true

[EG5]

if im not mistaken u just cant put k20a2 cams into a accord euro motor?

wouldnt you have to do a head swap?

k20a2 head will have provision for the third cam lobe. on the k20a2 head both ports are open, once vtec kicks in the valves are opened longer

where as a k24a3 head vtec machanism does not carry a third cam lobe and only opens up a second port when vtec is engaged

please correct me if im wrong but from what i have read, this seems to be true

You dont need to do head swaps to run k20a type R cams
What he needs is type R valve springs and k20a type R valve springs based.

i think you got mixed up with k24a3 USDM spec.

[LiL FiLo]

my bad! yonas correcto

[fatboyz39]

You dont need to do head swaps to run k20a type R cams
What he needs is type R valve springs and k20a type R valve springs based.

i think you got mixed up with k24a3 USDM spec.

Is it required if limiter is kept around 7400rpm?

[EG5]

Is it required if limiter is kept around 7400rpm?

if you want to rev it to 8000 rpm, valve springs from type R is required.

[Chris_F]

how reliable would an K24a3 be at those rpm? (assuming upgraded valve springs/retainers)

[integral90]

Yeah that's my question too... I thought the rods would be in much more danger earlier than the valvetrain

[EG5]

how reliable would an K24a3 be at those rpm? (assuming upgraded valve springs/retainers)

I will know soon as I got my buddyclub cams , valve springs , retainers , type r valve spring based installed last weekend. Dyno tuning will be on monday.

7600 rpm is proven to be all good on 06+ k24a3. Drove it for 1 year + 3 months without any problems .

[Chris_F]

Looking forward to hearing the result.

I'm hoping to have my car tuned soon and will be sticking with the proven 7600rpm.

Once I've upgraded the cams/valve tran, I'm hoping 8k rpm is possible.

[EG5]

Looking forward to hearing the result.

I'm hoping to have my car tuned soon and will be sticking with the proven 7600rpm.

Once I've upgraded the cams/valve tran, I'm hoping 8k rpm is possible.

177.5kw@wheels with buddyclub N+ cams , valve springs , retainers .
Gotta be happy with that as Im still running full exhaust with metal cat.

Next step is to tune it with open header + megaphone set up

[Chris_F]

177.5kw@wheels with buddyclub N+ cams , valve springs , retainers .
Gotta be happy with that as Im still running full exhaust with metal cat.

Next step is to tune it with open header + megaphone set up

damn, that's impressive.

So that's with the standard Accord Euro (k24a3) engine + buddyclub cams, cold air intake, intake manifold, header, metal cat and exhaust (3"?). Still using the standard VTC gear?

What rpm did you take the motor to?

:thumbsup::thumbsup: awesome power figure

[EG5]

damn, that's impressive.

So that's with the standard Accord Euro (k24a3) engine + buddyclub cams, cold air intake, intake manifold, header, metal cat and exhaust (3"?). Still using the standard VTC gear?

What rpm did you take the motor to?

:thumbsup::thumbsup: awesome power figure

standard bottom end , standard head from k24a3 euro , buddyclub n+ cams +valve springs + retainers , OEM DC5R valve springs seat base + valve stem seals , toda chain tensioner , 50 degree VTC , JDMyard intake manifold + 80mm throttle body + Velocity stack , JDMyard 4-2-1 header + 3 inch exhaust with metal cat .

I got 2006 k24a3 , 8k rpm rev limit.

[Chris_F]

Obviously an awesome combination of parts. Any chance of a dyno chart? :D

[EG5]

Obviously an awesome combination of parts. Any chance of a dyno chart? :D

http://i278.photobucket.com/albums/kk99/egk24/DSC09342.jpg?t=1227230207

Still running 98 Octane BP ultimate

[Tofu]

any ecu tuning or is that with stock ecu?

[EG5]

any ecu tuning or is that with stock ecu?

Hondata KPRO

[Benson]

any ecu tuning or is that with stock ecu?

LOL :p

[EGBOY]

177.5kw@wheels with buddyclub N+ cams , valve springs , retainers .
Gotta be happy with that as Im still running full exhaust with metal cat.

Next step is to tune it with open header + megaphone set up


thats impressive numbers, what sort of power would this setup make on a 2lt block? ( roughly )

[EG5]

thats impressive numbers, what sort of power would this setup make on a 2lt block? ( roughly )

Depends if its on jdm k20a or audm
On AUDM K20A around 150kw@wheels
On JDM K20A abit more than 150kw@wheels

[euRo.e]

what tranmission are you running? euro or dc5?

[EUR003act]

mmmmmm i so wanna run my K24/K20 to 8,000k...

just hope my choice in engine tuning can do it :o

[EG5]

mmmmmm i so wanna run my K24/K20 to 8,000k...

just hope my choice in engine tuning can do it :o

Too easy to do it
Im pushing it to 8100 rpm now
179kw@wheels

[EUR003act]

Too easy to do it
Im pushing it to 8100 rpm now
179kw@wheels

hehe yeah well my K20Z1 head stock runs to 8500rpm... so my valvetrain is all sweet!

its just my rods and oil pump i worry about lol

P.S im gonna need another (3rd lol) intake manifold gasket off you.. ill PM soon

[B18cEG]

Depends if its on jdm k20a or audm
On AUDM K20A around 150kw@wheels
On JDM K20A abit more than 150kw@wheels

On my mates Dc5-s k20z he makes 202whp with STOCK EVERYTHING just a cai and ecu, i can also get dyno paper but not for a few weeks.

[EUR003act]

On my mates Dc5-s k20z he makes 202whp with STOCK EVERYTHING just a cai and ecu, i can also get dyno paper but not for a few weeks.

lol i wanna run my car on that dyno! mmmmm 250whp here i come! :thumbsup:

[B18cEG]

lol i wanna run my car on that dyno! mmmmm 250whp here i come! :thumbsup:

hey, im just saying they were the numbers on the stock motor with tune, i will post up the paper and dyno type in a couple weeks

[EUR003act]

hey, im just saying they were the numbers on the stock motor with tune, i will post up the paper and dyno type in a couple weeks

sorry i wasnt having a go at you... different dynos give different readings, thats why id love to run my car on that same one! give me higher figures lol :thumbsup:

yeah post dyno sheet once youve found it, then we can see the torque curve! :thumbsup:

[EP3EVA]

EG5 what kind of exhaust set are you running??

[EG5]

EG5 what kind of exhaust set are you running??

3 inch exhaust
JDMyard 4-2-1 header

[felixd]

so will the k20a intake cams + type r valve springs work on the k24a3 block ? without ecu / kpro

[DR HONDA]

so will the k20a intake cams + type r valve springs work on the k24a3 block ? without ecu / kpro

It will work. Also if you use the 50deg actuator the ECU will definetely get confused without aftermarket ECU control. Why would you want to go backwards using K20A cams in a 2.4? The Euro cams especially 05YM onwards have a lot to offer especially with the use of a 50deg wheel and tuning, ask Yonas:thumbsup:

[TheSaint]

old thread - but the best that a search came up with

does anyone know if the 2006+ Euro has the better intake cam like the US TSX does?

do our australian CL9 euro's have the same cam specs from 2003-2005 and then the better intake cam from 2006+

basic question is would the AUDM 2006+ or USDM 2006+ euro/tsx intake cam be a good upgrade for a 2004 model 6mt euro (K24a3)
(would be installed along with toda 40deg VTC)

[Vvvtec]

Afaik, no, we didnt get the bigger cam.

Get yourself an 08+ TSX cam.

K20a.org is your friend with these types of questions.

[TheSaint]

cheers for the quick info =)

does the 08+ intake cam and 40deg VTC require engine management to run?

i was about to order a flashpro from hondata but realised they dont work on the older TSX - do we have the same problem with the older euro's?

is there any alternative engine management systems that people are using with their K24's?

[Benson]

What year euro do you have?

[TheSaint]

mine is a 2004 CL9 6-spd manual

starting to get conflicting info - some people saying the 2008 is the CU2 and the cam doesnt fit
some people saying our 2006+ CL9 has the better cam - some people saying in australia - it doesnt

also getting alot of australian feedback saying not to bother without engine management and that theres no way to keep cruise and VSA with it
yet the yanks say its still worth the gain - but management will give the maximum potential (same with any engine mod really)

trying to put together a plan of attack for the euro - so far i only have comptech icebox
but i want to get comptech/toda etc headers, a good quality cat, the better intake cam, toda or milled 40deg VTC and eventually engine management
keeping the OEM exhaust - only other mods are FN2 Type-R 18" wheels and ill be getting Eibach Pro springs as well - keeping it fairly simple and clean =)

[Benson]

mine is a 2004 CL9 6-spd manual

starting to get conflicting info - some people saying the 2008 is the CU2 and the cam doesnt fit
some people saying our 2006+ CL9 has the better cam - some people saying in australia - it doesnt

also getting alot of australian feedback saying not to bother without engine management and that theres no way to keep cruise and VSA with it
yet the yanks say its still worth the gain - but management will give the maximum potential (same with any engine mod really)

trying to put together a plan of attack for the euro - so far i only have comptech icebox
but i want to get comptech/toda etc headers, a good quality cat, the better intake cam, toda or milled 40deg VTC and eventually engine management
keeping the OEM exhaust - only other mods are FN2 Type-R 18" wheels and ill be getting Eibach Pro springs as well - keeping it fairly simple and clean =)

Ive done 2 Honda euro accord now with the Hondata Flashpro. One was an 04 and 07 manual. Both required 07-08 TSX ECU upgrade, CAN bus adaptor and Hondata Flashpro. All function works perfectly fine. I have a complete package in stock. Email me on benny@bypracing.com for futher details

Here is what i recommend base on what i've put on fellow Euro customers -
- PLM Header 4-2-1 for TSX
- RBC intake manifold
- J35 65mm Throttle body DBW
- CAI
- 50vtc gear
- Upgraded mid pipe with high flow CAT
- Hondata Flashpro

Expect 145-150kw at the wheels once tuned properly

[Benson]

With regards to OEM cam upgrade, i wouldnt bother. Just leave it and work on the bolton mods. If you want more power after all the bolt-ons, go with a stage 2 camshaft upgrade and that will give you another 10kw across the powerband. Other mods with the stage 2 camshatfts is recommended to make it work all together

[TheSaint]

i wouldnt use a 50deg VTC if you paid me to - i wouldnt trust the ECU to hold it back from the 45+ line
TODA 40deg or a machined stock unit would be alot safer

the cam spec on the 2006+ intake cam is one of the best setup cams that honda has ever produced
im very keen to build around it and see what kind of results i get
http://www.hondatuningmagazine.com/tech/htup_1209_acura_tsx_power_struggle/

i just have to make sure i get the right one

i also wouldnt use a CAI on this car/engine
i really like the results from the comptech icebox as seen here and felt on my car from switching between different intakes:
http://www.heeltoeauto.com/tech-articles/engine/intake-shootout-04-08-acura-tsx.html

[Vvvtec]

lol @ 50deg gear comment

[Chr1s]

With regards to OEM cam upgrade, i wouldnt bother. Just leave it and work on the bolton mods. If you want more power after all the bolt-ons, go with a stage 2 camshaft upgrade and that will give you another 10kw across the powerband. Other mods with the stage 2 camshatfts is recommended to make it work all together


^ this.

I've mixed and matched OEM cams in the past on my K24 and the results were not worth the trouble.

[TheSaint]

lol @ 50deg gear comment

why?

why would i want to use a 50deg RSX VTC when theres a chance of valve kiss
its just as much trouble and effort to use a toda unit or make your own
sure some people use them and use engine management to limit it
but its still not a 100% sure bet

healthy debate is good

chr1s - any more details on what cams you used and what results you got?
which engine was it? pre-facelift K24a3?

getting very black and white information from american forums vs australian forums
the USDM K24a2 isnt that much different to the AUDM K24a3 is it?

[Benson]

Havent had any issue with using brand new 50VTC gear with big cams and limiting it to 35-40vtc

[mocchi]

i wouldnt use a 50deg VTC if you paid me to - i wouldnt trust the ECU to hold it back from the 45+ line
TODA 40deg or a machined stock unit would be alot safer

the cam spec on the 2006+ intake cam is one of the best setup cams that honda has ever produced
im very keen to build around it and see what kind of results i get
http://www.hondatuningmagazine.com/tech/htup_1209_acura_tsx_power_struggle/

i just have to make sure i get the right one

i also wouldnt use a CAI on this car/engine
i really like the results from the comptech icebox as seen here and felt on my car from switching between different intakes:
http://www.heeltoeauto.com/tech-articles/engine/intake-shootout-04-08-acura-tsx.html

dont use it if you dont wanna use it but dont say it as if youve known it to be true.

50 vtc is fine for k24a3 with 06 tsx intake cam.

inb4ban

ohwait

[TheSaint]

have any of the people that are saying that the 50deg VTC is ok to use on this setup actually clayed an engine or tested it at high rpm?
on the USDM version of this engine there is a higher risk of valve to piston contact AT 50deg VTC with the 2006+ intake cam

rather than cheaping out and slapping in an RSX OEM 50deg VTC and relying on EMS to keep the degrees back
(bare in mind the tolerance is +/- 3 degrees for VTC systems and the 2003-2005 k24a3 has slightly shallower piston valve reliefs)
wouldnt it be prudant to just buy/make a 40 or 45 deg VTC mechanism so you KNOW it will never be a problem?

seems that if you are going to go to the effort at least do it properly eh?

http://hondata.com/tuning_k24a2_tsx_engine.html

Hondata on using the OEM 50deg VTC:
"Although you could probably purchase and bolt on an RSX VTC mechanism for 50 degrees travel, there is less valve to piston clearance on the TSX pistons. Our measurements suggest 45 degrees maximum cam movement is much safer. Allowing the full 50 degrees movement leads to a greater risk of valve to piston contact should you accidentally mis-shift and over-rev."

http://hondata.com/help/flashpro/index.html?tuning_for_vtc.htm

Hondata on tuning VTC with EMS:
"Warning
With Honda cams there is a physical stop limiting cam advance to prevent valve to valve contact and valve to piston contact. With after market cams it is up to the manufacturer to ensure that the cam lobes are positioned so that valve to valve and valve to piston contact is not possible. Because the cam control mechanism uses a closed-loop feedback system, limiting the cam position in the ECU will not guarantee that the cam position will not exceed what is set in the ECU. Because of this all cams must have a physical stop to prevent valve contact."


Results of VTC slippage (cammed motor but still good read):
http://www.k20a.org/forum/showthread.php?t=7661

[mocchi]

I got k24a3 with new tsx 06 intake cam and 50 vtc. I rev it to 8k.
Bought in cam new from auto fair.

Do you have it in your jdm deefuf.. I mean cl9?
You insist on what you think is correct? Byp guys have a lot more experience and they've done it.
You should take their advice just like you take advice from hondata

Don't be so easily biased I guess.

[EKVTIR-T]

I think he's just being cautious

its a leap of faith to trust internet people and risk blowing up your pride and joy

so I kinda see his perspective,but as above guys have tried and tested it already

[mocchi]

I think he's just being cautious

its a leap of faith to trust internet people and risk blowing up your pride and joy

so I kinda see his perspective,but as above guys have tried and tested it already

yeah its been done and its fine.
his comments were misleading saying "i wouldnt use a 50deg VTC if you paid me to - i wouldnt trust the ECU to hold it back from the 45+ line"
saying that no one should ever use 50 vtc with 06 intake cam.

[EG5]

Ive been using 50 degree VTC on my k24a3 since 2006
8500 rpm rev limit. Engine done 200 passes down the 1/4 mile and say 30 track days.
No problem so far.

[TheSaint]

well nobody has shown any proof otherwise
at least hondata links have proven results and are a reputable company
havnt heard of any of these guys before - so what makes them different?
they only suggested otherwise - no proof

[TheSaint]

Ive been using 50 degree VTC on my k24a3 since 2006
8500 rpm rev limit. Engine done 200 passes down the 1/4 mile and say 30 track days.
No problem so far.

theres a voice i know and trust
is that with stock cams at all?
and which version of the intake cam did it have stock?

[mocchi]

well nobody has shown any proof otherwise
at least hondata links have proven results and are a reputable company
havnt heard of any of you guys before - so what makes them different?
they only suggested otherwise - no proof

what you mean no proof, lotta guys from US done that.
yes there were some that physically limit vtc movement to 45. hytech does this mod too.

lotta guys here in au done that too but you cant seem to believe otherwise.

[TbM]

i also wouldnt use a CAI on this car/engine
i really like the results from the comptech icebox as seen here and felt on my car from switching between different intakes:
http://www.heeltoeauto.com/tech-articles/engine/intake-shootout-04-08-acura-tsx.html

ummm in that link the k & n cai seems to be equal to or make more power/talk than the icebox everywhere but 2300-3k rpm range so dont know what your point is unless im reading the graph wrong.


http://heeltoeauto.com/gallery/var/resizes/Product-Features/TSX-Intake-Comparo/CTE%20KN%20Injen.JPG?m=1341414582

Graph showing our top three finishers. K&N is the red dashed line, CT is the green, and the Injen is the solid red.

[TheSaint]

the k+n makes a very slight over all improvement over the icebox
but the icebox retains alot more torque and has a much nicer sound
(look at the icebox torque spike)

read the article - iv tested both on CL9 and its pretty much what they say

[Vvvtec]

Im running karcepts cai on my k24. Seems to like it. Lol.

Also running 50vtc.

[newpaddy3]

the k+n makes a very slight over all improvement over the icebox
but the icebox retains alot more torque and has a much nicer sound
(look at the icebox torque spike)

read the article - iv tested both on CL9 and its pretty much what they say

A whole 5.279lbft more!

Nice!

[TheSaint]

just under 3000rpm
spikes a good 12lbft
and similar results have been reported by others from other forums
the extra size of the box really helps the engine to get up and go at lower rpms
but CAI would be the way to go once the car is geared more toward top end

the icebox just sounds so good tho lol

[wuism]

I'm using 50deg vtc with stock bottom block and Toda spec c cams. Limit to 40deg and rev to 8300rpm. Tracked car already as well and no issues....

[TheSaint]

im just not sure how much i would want to rely on EMS to limit something that could potentially damage the engine
at least with 40-45deg VTC there is a mechanically stop so that it will never happen

what management you using wuism - and when are you taking it to the track next?

[Vvvtec]

No one is forcing you to use the 50deg VTC. if you can get your hands on a pinned/modded gear, do it.

Or better yet delete the VTC system off your K24 so the ecu cant fuk anything up at all :p

[wuism]

Kpro and going again in march...

[EG5]

theres a voice i know and trust
is that with stock cams at all?
and which version of the intake cam did it have stock?

7800 rpm with stock cams ( stock k24a3 cams + 50' vtc)
8500 rpm with Buddyclub N+ cams , valve springs , retainers + 50' vtc)
Im still using the same motor till today. Still running strong.

[mugsee]

My 2 cents:

Having an ECU hold a certain cam angle is not the most reliable of methods to prevent P2V contact, and if you inspect the cam angle on a datalog, you might be surprised at how much over/under your nominated cam angle your motor move to, because of mechanical behavior. Thats why tuners will generally limit their max cam angle to give a buffer for error within their tune.

Also:
- VTC set at 45 degrees doesn't do much for a stock K24A3 so theres no need to play with cam angles that high.
- Even if you set your VTC to 50 degrees, theres no hard evidence that says that driving it within its limits (not over-revving) will create P2V within a standard K24A3. Non-stock motors are a different story.

[TheSaint]

thats why in an earlier post i said that you must consider an angle tolerance of plus or minus 3degrees when tuning VTC

i think 40deg would be max for a stock engine, like you said, 45-50 really wouldnt help much
hence the Toda 40deg being a great bolt on product (not that its hard to modify a stock one if theres a reliable machinist nearby)

and again - i am still trying to find somebody that has clayed a motor running high VTC to see what kind of clearances there actually are
there are stories of VTC slipping past their allowed tolerance at both low constant RPM (cruising) and high raising RPM (acceleration)
in most cases the bottom end is destroyed along with valves - even if one cylinder goes first the intake manifold will be filled with peices of piston and valve which get sucked back into the other cylinders

[hanzzi]

Im using a stock RBC (50deg) vtc gear and have pined it to 40deg using tractuff vtc limiter which cost $30.

http://shop.tractuffstuff.com/TracTuff-K-Series-VTC-Limiter-TT-VTCL.htm

Dont waste your money buying a toda or Hytek vtc gear.

I have also done many datalogs and i have never spiked over 40 deg.

[TheSaint]

thats actually a very good solution hanzzi - thanks for the info on that =)
since we have a cnc mill at work im going to just get a stock 25deg VTC gear machined out
but if the workshop doesnt have time this could be a simple and cheap alternative

[nuk1ear]

what was the basic conclusion on this? If you have a K24a3 engine being put back together and you have both sets of cams (06 k24a3 cams and k20a2 cams) sitting there, which ones are best to use? I gather theres very little difference? More mid range with the a3, slightly more top end with the a2?

[RenzokukenJ]

K20z4 cams

[newpaddy3]

personally i like to use my penis to actuate the valves for maximum lift and duration.

nothing beats a beaten knob

http://www.ozhonda.com/forum/customavatars/avatar28992_27.gif

[nuk1ear]

hmmm i guess it was a waste of time posting here then

[Fredoops]

what was the basic conclusion on this? If you have a K24a3 engine being put back together and you have both sets of cams (06 k24a3 cams and k20a2 cams) sitting there, which ones are best to use? I gather theres very little difference? More mid range with the a3, slightly more top end with the a2?

http://www.k20a.org/forum/showthread.php?t=76662

stock k20a2 cams wont do much.

if you insist on stick to OEM cams then the Post Facelift Acura tsx intake cams from the LATE model K24A2 is the one to go for.

[nuk1ear]

I dont insist on anything, I simply have both sets of cams here and im putting my engine together and wondering if theres any preference.

[Vvvtec]

K20 intake k24 exhaust

[nuk1ear]

K20 intake k24 exhaust

Cool, any reason? Taking the 2 cams with highest lift is preferred? duration difference on the exhaust is very small (few degrees less for the k24 cam)

[webbrowan]

Thanks everyone for sharing your personal experiences regarding this topic of discussion especially Dr Honda for the technicality involving the ECU. Sometimes before visiting an actual shop for your motor needs, you need to get suggestions and who else better to help you with those if not experienced ground users who have had hands-on experience before.