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L8eight
05-01-2006, 09:15 AM
I am looking @ cams right now, and i am wondering what the max lift you can run w/ out having to replace the stock valvetrain. i have read alot of different things but most of them got me more confused. anyhelp is welcomed :)

-Rocky

drunk monkey
05-01-2006, 09:29 AM
the way i hear it is lift or duration doesnt matter its revs that matters if you want to change the the valvetrain. now this is coming from a guy who use to own a high reving honda motor. but it also depends on the cams on where it makes power. ie honda skunk2 stage 2 doesnt make power till past the stock redline. i dont know if the evo cams from hks or any others are design to have stock redline. or if the cams move the powerband up or down.


carlo

dohcvtec
05-01-2006, 09:38 AM
the way i hear it is lift or duration doesnt matter its revs that matters if you want to change the the valvetrain. now this is coming from a guy who use to own a high reving honda motor. but it also depends on the cams on where it makes power. ie honda skunk2 stage 2 doesnt make power till past the stock redline. i dont know if the evo cams from hks or any others are design to have stock redline. or if the cams move the powerband up or down.


carlo
Duration doesn't matter as much as lift does with valve springs. The higher the lift you go, you can run into coil bind on stock springs. Duration could be a factor if the duration is too much, the ramp angle could be really steep. I say the HKS 272 with its 10.2 (? or is it 10.8, i forget) mm lift would be max for stock springs.

drunk monkey
05-01-2006, 09:43 AM
Duration doesn't matter as much as lift does with valve springs. The higher the lift you go, you can run into coil bind on stock springs. Duration could be a factor if the duration is too much, the ramp angle could be really steep. I say the HKS 272 with its 10.2 (? or is it 10.8, i forget) mm lift would be max for stock springs.

good info. i knew it was something liek that. haha so 272 is the max the stock springs can go. now is that stock redline?


Carlo

dohcvtec
05-01-2006, 09:48 AM
Duration doesn't matter as much as lift does with valve springs. The higher the lift you go, you can run into coil bind on stock springs. Duration could be a factor if the duration is too much, the ramp angle could be really steep. I say the HKS 272 with its 10.2 (? or is it 10.8, i forget) mm lift would be max for stock springs.

good info. i knew it was something liek that. haha so 272 is the max the stock springs can go. now is that stock redline?


Carlo
Yes, all assuming stock redline. I know people are running 280's on stock spirngs, but again they have the same lift as the 272's, so you should be fine. If anything had any more lift than the HKS cams, I would get springs.

L8eight
05-01-2006, 09:49 AM
I believe what DOHCVTEC means is that duration is not the issue, as it just keeps the valves open for longer, but lift is how high the valves open up. if they open too high for stock valve springs the springs bind and can cause valve float.

so my quistion is with the cosworth cams which have a lower duration, but a 11.0mm lift on both intake and exhaust cams can i run my stock springs? or would i be pushing it?

dohcvtec
05-01-2006, 09:51 AM
I believe what DOHCVTEC means is that duration is not the issue, as it just keeps the valves open for longer, but lift is how high the valves open up. if they open too high for stock valve springs the springs bind and can cause valve float.

so my quistion is with the cosworth cams which have a lower duration, but a 11.0mm lift on both intake and exhaust cams can i run my stock springs? or would i be pushing it?
You would be pushing it for sure.

SouthernCrane
05-01-2006, 09:57 AM
I believe what DOHCVTEC means is that duration is not the issue, as it just keeps the valves open for longer, but lift is how high the valves open up. if they open too high for stock valve springs the springs bind and can cause valve float.

so my quistion is with the cosworth cams which have a lower duration, but a 11.0mm lift on both intake and exhaust cams can i run my stock springs? or would i be pushing it?

IMO, If you are going to spend the money on the Cosworth cams (or any cams) and have the head open, I would just replace your valve springs and retainers at the same time for peace of mind.

Jamie@WORKS
05-01-2006, 10:43 AM
I believe what DOHCVTEC means is that duration is not the issue, as it just keeps the valves open for longer, but lift is how high the valves open up. if they open too high for stock valve springs the springs bind and can cause valve float.

so my quistion is with the cosworth cams which have a lower duration, but a 11.0mm lift on both intake and exhaust cams can i run my stock springs? or would i be pushing it?

IMO, If you are going to spend the money on the Cosworth cams (or any cams) and have the head open, I would just replace your valve springs and retainers at the same time for peace of mind.

+1

The additional labor with the cam install is fairly small. There's no reason not to do them.

mikeart
05-01-2006, 11:00 AM
I believe what DOHCVTEC means is that duration is not the issue, as it just keeps the valves open for longer, but lift is how high the valves open up. if they open too high for stock valve springs the springs bind and can cause valve float.

so my quistion is with the cosworth cams which have a lower duration, but a 11.0mm lift on both intake and exhaust cams can i run my stock springs? or would i be pushing it?

IMO, If you are going to spend the money on the Cosworth cams (or any cams) and have the head open, I would just replace your valve springs and retainers at the same time for peace of mind.

+1

The additional labor with the cam install is fairly small. There's no reason not to do them.

so then which valve springs and retainers are good? i haven't seen to many recommendations out there for what to get

dohcvtec
05-01-2006, 11:43 AM
In every case i've seen the cam manufacture has springs/retainers they recommend.

L8eight
05-01-2006, 12:14 PM
in that case i think i may do the revolver springs/retainers, and possibly the revolver cams, cosworth, or maybe even the pipers...

WORKS Engineering
05-01-2006, 05:47 PM
The height of the stock retainer does not allow the use of higher lift (than stock) cams. This results in the bottom of the retainer making contact with the valve stem seal with each revolution.

We highly recommend our WORKS valvetrain kit with our Power Cams and designed our retainers with Titanium considering the lightness of the stock retainers which are made of some "Unobtainium."

http://www.worksevo.com/store/product_info.php?cPath=21&products_id=33

L8eight
05-01-2006, 06:09 PM
how much more is labor are we talking like an hour, or 2-3 hours? if its a few more hours then i might just do HKS 272's...

Stormtrooper
05-01-2006, 06:28 PM
if you're planning to do any autox i would recommend valvetrain to allow for safe higher revs...

Its saved me from a few 3rd gear shifts on the straights.

EVO GRIM
05-01-2006, 06:39 PM
Hks and buddy club with stock lift you are ok. My pipers are 11.2 so I had to upgrade. Depends on what you want to do. Higher revs the upgraded springs/retainers are insurance eaven for stock lift.

L8eight
05-01-2006, 08:39 PM
would i be making more power with the higher lift cams? or is it all around the same +/-5 whp ballpark of each other

evo_dadi
05-01-2006, 09:08 PM
just stick with HKS ;) :lol:

L8eight
05-01-2006, 10:21 PM
just stick with HKS ;) :lol:

just noticed that HKS 280's have a reletively low lift (10.2 on both sides) which i am sure is compensated for with thier huge duration :shock: so if i do go HKS, it will most likely be the 280's.

evo_dadi
05-01-2006, 10:24 PM
doooo eeeeettt :lol: at least the 272's.

L8eight
05-01-2006, 10:33 PM
well if i am going to do 272's i might as well do 280's :twisted: lol

Matz
05-02-2006, 05:51 AM
doooo eeeeettt :lol: at least the 272's.

If you can find anyone that actually has them in stock. :wink: They've been on backorder for a couple of months at least... that's one of the reasons why I ended up getting 269s.

Jamie@WORKS
05-02-2006, 12:04 PM
how much more is labor are we talking like an hour, or 2-3 hours? if its a few more hours then i might just do HKS 272's...

A little over an hour with the cams. Or you can pay for the cam labor all over again if you decide to do it in the future ;)

Racecentric1
05-02-2006, 12:19 PM
I have Tomei 280's in stock.

drunk monkey
05-02-2006, 12:21 PM
how much more is labor are we talking like an hour, or 2-3 hours? if its a few more hours then i might just do HKS 272's...

A little over an hour with the cams. Or you can pay for the cam labor all over again if you decide to do it in the future ;)


how easy is it to install cams? i have done cams install on a honda dohc before. is it relatively the same? or is shims involved to get the valve clearance correct?

Carlo

Jamie@WORKS
05-02-2006, 12:36 PM
how much more is labor are we talking like an hour, or 2-3 hours? if its a few more hours then i might just do HKS 272's...

A little over an hour with the cams. Or you can pay for the cam labor all over again if you decide to do it in the future ;)


how easy is it to install cams? i have done cams install on a honda dohc before. is it relatively the same? or is shims involved to get the valve clearance correct?

Carlo

No shims to contend with in the EVO. I've never dealt with Honda internals, so can't say, but would guess it's relatively the same on the scale of difficulty. There is the balance shaft and a few other items to deal with on the EVO. Springs/retainers aren't too difficult, but do require patience, a little finesse, a compressor and more special tools.

dohcvtec
05-02-2006, 01:42 PM
how much more is labor are we talking like an hour, or 2-3 hours? if its a few more hours then i might just do HKS 272's...

A little over an hour with the cams. Or you can pay for the cam labor all over again if you decide to do it in the future ;)


how easy is it to install cams? i have done cams install on a honda dohc before. is it relatively the same? or is shims involved to get the valve clearance correct?

Carlo

No shims to contend with in the EVO. I've never dealt with Honda internals, so can't say, but would guess it's relatively the same on the scale of difficulty. There is the balance shaft and a few other items to deal with on the EVO. Springs/retainers aren't too difficult, but do require patience, a little finesse, a compressor and more special tools.
Carlo, I come from working on Honda heads myself. Although I've never done a cam swap on the Evo, I hear the tough part on the Evo is the balance shaft. I guess it can easily skip a tooth and is easy to mix up 180 degrees off. I assume this is why people zip tie the cam gears to the timing belt and replace one cam at a time, reattaching the cam gear before moving onto the next, to avoid messing with the balance shaft.

smack
05-02-2006, 02:05 PM
I assume this is why people zip tie the cam gears to the timing belt and replace one cam at a time, reattaching the cam gear before moving onto the next, to avoid messing with the balance shaft.
i did it this way except i did both cams before putting gears back on since when the gears are zip tied to the belt you can't really get one on without the other very easily. i just felt like it's safer to move the whole thing as one and only one time.

Liquid-R1
05-02-2006, 10:15 PM
One of the Socal mods is selling a set of HKS 272/272's...

http://www.socalevo.net/index.php?option=com_smf&Itemid=26&topic=21930.0

Matz
05-02-2006, 10:24 PM
One of the Socal mods is selling a set of HKS 272/272's...

http://www.socalevo.net/index.php?option=com_smf&Itemid=26&topic=21930.0

WTH? Goku searched high and low for those cams a couple of months ago, and he's already getting rid of them? I wonder why. :?:

Liquid-R1
05-03-2006, 01:55 PM
WTH? Goku searched high and low for those cams a couple of months ago, and he's already getting rid of them? I wonder why. :?:

Not sure, but I heard he goes through cams like no tomorrow. No reason, just keeps getting different ones.

:?

EVO GRIM
05-03-2006, 07:02 PM
It's true I bought my pipers from him.

EFIxMR
05-04-2006, 01:06 AM
the cosworth cams go by actual duration measured at .050 lift, thats why the numbers seem lower.

hks goes by advertised duration in which case the cosworth m2 would be near 280.

cosworth m2 cams are designed to be used with upgraded valvetrain.

they also make a lower lift profile that can be used with stock valvetrain.