Camshaft Guide for SOHC

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Calesta
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Camshaft Guide for SOHC

Post by Calesta »

I put together a text file a while back with cam information for the SOHC KA24E. I figured I'd go ahead and post it here to help out everyone who's always asking about cam specs.

Format:

Cam name / part number
Description
Specs
Comments from manufacturer / retailer / forum
Installation notes (if any)
Link to information verifying specs or link to store to order cam

-----

KA24E cams

Price current as of 10/31/2004


89-90 240sx STOCK cam
intake: 240 degrees duration, .409 in valve lift
exhaust: 248 degrees duration, .409 in valve lift
http://home.att.net/~mabuhaycarlos/Cam.html

90-97 Hardbody STOCK cam
intake: 232 degrees duration, .382 in valve lift
exhaust: 232 degrees duration, .382 in valve lift
http://forums.nicoclub.com/zerothread?id=58181 (from lovemysan2's factory service manual)

HybridKA - KA24E Stage 1 GB4 $185 + core charge (?)
Intake 270 duration, .443" Lift
Exhaust 272 duration, .448" Lift
note: core exchange required
http://www.hybridka.com/sohccustom.htm

4x4parts - High Performance Cam $319.95
Billet, no core required
270 degrees duration, .402 in valve lift (same as R4 Nismo cam)
"These cams will give you a 15% increase in horsepower. They are ground to specification for optimum setting. Specifically designed to increase midrange performance. .402"/270* lift and duration. Highly recommended to replace stock rocker arms which are sold separately. 12 required. All cams are ground from billet, not reground."
http://www.4x4parts.com/public_html/sho ... 0725d8c89e

PDM - C.406 $200 + $250 core charge
Regrind, requires stock core
Intake 260 degrees duration, .424 in valve lift
Exhaust 268 degrees duration, .441 in valve lift
"mild performance upgrade, that wakes up any stock engine with good emissions results, and good in automatics."
http://www.pdm-racing.com/products/cam_corner.html

PDM - C404.H $200 + $250 core charge
Regrind, requires stock core
Intake: 268 degrees duration, .441 in valve lift
Exhaust: 272 degrees duration, .447 in valve lift
"Strong performer, with good midrange pull to redline. O.K. with automatics. Our strongest seller with the most smiles!"
note: requires cam towers to be milled .025 in
http://www.pdm-racing.com/products/cam_corner.html

PDM - C.404.HTurbo $200 + $250 core charge
Regrind, requires stock core
Intake: 268 degrees duration, .441 in valve lift
Exhaust: 272 degrees duration, .447 in valve lift
"Same strong performance as our naturally aspirated C404 cam, but designed with less overlap to ease with the exhaust valves on a turbo motor. Very good good midrange pull to redline."
note: requires cam towers to be milled .025
http://www.pdm-racing.com/products/cam_corner.html

PDM - C.411.H $300 + $250 core charge
Regrind, requires stock core
Intake: 300 degrees duration, .506 in valve lift
Exhaust: 300 degrees duration, .506 in valve lift
"Full race - not very streetable, and requires stiffer valve springs, computer re-programming and possible injector and fuel pump upgrades. Not a bolt-in cam, and not recommended for street use."
note: requires cam towers to be milled .060"
http://www.pdm-racing.com/products/cam_corner.html

Gude Bullfrog - Performance Cam: Part # NSCS03
(909) 244-3533
intake: 228 degrees duration, .500 in valve lift
exhaust: 228 degrees duration, .500 in valve lift
"First time I called to speak to a rep, a female who assisted me was only able to quote me a price for the cam which was $577.50. Second time I called, I spoke to Bill himself. He told me there was a 15 HP increase in the high rpm range. Then HE quoted me a price of the cam for $750. ??? Then he turned into a salesmen and tried to sell me a head package (including the cam) for a 40 HP increase. Becareful with these guys, although they DO great work, just make sure all quotes are correct."
http://home.att.net/~mabuhaycarlos/Cam.html
Description: Strong from 4000 rpm to redline
Power band: 4000 rpm to 6800 rpm
Idle: Good
http://www.gude.com

Jim Wolf Technology - Part # A2409-N00S1 (Discontinued)
(619) 442-0680
"Jim Wolf has discontinued their auto-cross billet cam. A 2nd cam for the SOHC 240 is in still in development and won't be avaliable till late September. Jim Wolf rep told me that the cam will sell around $400."
http://home.att.net/~mabuhaycarlos/Cam.html

Nissan Motorsports: (310) 538-2610

Nissan Motorsports - R6 "High Performance" $317.50
(866) 754-5500 (nissanparts.cc)
intake: 248 degrees duration, .422 in valve lift
exhaust: 256 degrees duration, .422 in valve lift
"R6 is a milder cam designed to work with automatic trans"
http://www.nissanparts.cc/catalog/?section=316

Nissan Motorsports - R4 "High Performance" $317.50
(866) 754-5500 (nissanparts.cc)
intake: 270 degrees duration, .402 in valve lift
exhaust: 270 degrees duration, .402 in valve lift
"The R4 camshaft is a mild range/loopy idle for manual trans cars"
http://www.nissanparts.cc/catalog/?section=316
"I talked to a female rep at Nissan motorsports. She told me the cams were currently out of stock, they sell for about $300 and at 6000 RPM there is a 20 HP increase."
http://home.att.net/~mabuhaycarlos/Cam.html

Nissan Motorsports - R5 "Race" $317.50
(866) 754-5500 (nissanparts.cc)
intake: 288 degrees duration, .550 in valve lift
exhaust: 292 degrees duration, .563 in valve lift
"The R5 race cam requires the use of race pistons and alternate valve train components."
http://www.nissanparts.cc/catalog/?section=316

Nissan Motorsports - KA24E billet blank $190.50
(866) 754-5500 (nissanparts.cc)
"Cam lobes are underground. SOHC 12-valve engine only."
http://www.nissanparts.cc/catalog/?section=316

Nissan Motorsports - KA24E cam sprocket $66.04
(866) 754-5500 (nissanparts.cc)
"OE KA24 SOHC sprocket modified to use offset bushing for adjusting cam timing. Selection of bushings included. For use with OE timing chain only."
http://www.nissanparts.cc/catalog/?section=316
Last edited by Calesta on Fri Aug 05, 2005 7:05 am, edited 1 time in total.
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Post by veilside180sx »

Good to have, had similar list on my laptop...but you picked up some that I missed.
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Post by -Incomplete- »

Have a cam to add to that list....

KA24E Stage 1 GB4

Intake 270 duration, .443" Lift
Exhaust 272 duration, .448" Lift

From www.hybridka.com

PPL are very friendly and seem to adament about performance

No idea of the HP gains...

OOPPS! Didnt see his post^^^^^^^^^^^^^^^^^^
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Post by SOHC 240SX »

People love to hear advertised cam duration values. Supposedly, these numbers represent how many degrees of a circle (total 360) that the camshaft is acting on or depressing the valve. Unfortunately, these numbers don't really tell us a whole lot. This is because there is NO set standard for where advertised duration is measured. Remember that all cams have 360 degrees of duration at 0.000" of lift. So, at 0.004" of lift, a cam may have 268 degrees of duration but at 0.002" of lift, the same cam may have, lets say, 280 degrees of duration. At 0.010", this same cam may now have only 242 degrees of duration. As you can see, advertised duration means almost nothing because there is no standard to were and when to take measurements. To make things worse, not much air can flow through a valve until it is depressed at least 0.050". Advertised duation values tend to sell cams, so this information is pretty much junk. It is important to ask the dealer to quote you the duration at 50 thou. This will tell you how long you valve will be open from opening half way to closing half way....the period of duration when you can flow the most air to make power.

As you can see from above, PDM/Colt cams C404 turbo cam advertises the cam to have 268 degrees for the intake and 272 degrees for the exhaust. They wouldn't quote me duration at 0.050" because "they didn't want their cams to be copied". So I took my cam to my machinest and this is what we found.

Duration @ 0.050": Intake: 178 degrees Exhaust: 184 degrees

You can see how it is way off from the advertised specs. Lift was also off as well. On american V8 motors, valve lift is measured at the push rod. The rod moves up and down giving true valve lift. But on the KA24E, we have rocker arms. They pivot back and forth in a rocking motion. So getting a true reading of valve lift is impossible. So my machinest measured the valve lift at the valve itself with the lash set on the cam. This is what we found.

Valve lift @ valve w/ lash set: Intake: .407" Exhaust: .405"

These specs aren't very aggressive, but for a turbo motor, the cam doesn't need to be so. If I am not happy with the numbers I make with this cam, I will probably swap out for something more aggressive. Probably 210-225 duration @ 50 thou.
-los
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Post by Joel07 »

Actually advertised duration is measured at .006". If someone is measuring adv. duration at something other than .006", they're doing it wrong.

American V8's have rocker arms too. The difference is, we know the ratio's on the V8's, so we simply measure the cam lobe lift, and multiply it by the rocker arm ratio to find valve lift. Could do the same thing with the SOHC if we knew the rocker arm ratio. I'll have to see if I can measure a SOHC rocker arm and find the ratio if someone doesn't know it.

Also, interested in knowing how you measured the lift at the valve. Do you have the solid rocker conversion? It's impossible to test with a hydraulic lifter, because with no oil pressure to keep the lifter pumped up, it'll collapse a certain amount before you ever actually see lift at the valve.

Pretty amazing that they advertise 268/272, but only get 178/184 at .050". That must be one crazy looking lobe to get 90* of duration in .044" of valve lift! :shock: :D
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Post by veilside180sx »

^IIRC he is running a solid lifter conversion.
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Post by veilside180sx »

^IIRC he is running a solid lifter conversion.
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Post by SOHC 240SX »

Joel07 wrote:Actually advertised duration is measured at .006". If someone is measuring adv. duration at something other than .006", they're doing it wrong.

so we simply measure the cam lobe lift, and multiply it by the rocker arm ratio to find valve lift. Could do the same thing with the SOHC if we knew the rocker arm ratio. I'll have to see if I can measure a SOHC rocker arm and find the ratio if someone doesn't know it.

Also, interested in knowing how you measured the lift at the valve. Do you have the solid rocker conversion?
Ok, you said advertised duration is measured at .006" and if you don't do it that way, it is wrong. :shock: By who's standards? Who decided it was correct to measure at that lift instead of another section of lift? Can you prove to me this is an accepted standard rule in the automotive industry? Can you show me that everyone follows this "set standard"? How is this standard enforced so that all dealers properly quote cam specs at this exact lift? Do big name companys like Crower, Comp Cams, and Crane cams all follow your rule or do they measure duration as soon as the dial begins to move?????

Their is no set standard. Everyone measures advertised duration differently. If everyone starts doing it the same way, that is when a standard will be set. Right now, measuring at 0.050 thou is the semi-used standard for the industry, but not set in stone.

OE rocker arm ratio is 1.422:1

Yes, I do have the solid rocker arm conversion.

You can't measure valve lift on a rocker arm that pivots back and forth. Only ones that move up and down, such as the pushrod. As the rocker arm pivots, it is creating slack and will give totally false readings. The only parts that acutally moves up and down in the KA24E is the valve itself. So that is were the valve lift measurement was done once the slash was set. Once you have the measurements, then you can use your formula to get valve lift.
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Post by Jordan Gladman »

deviousKA wrote:
BTW, PDM lists a c404 turbo grind, that they advertise has less overlap. This is incorrect, as there is no possible way with a regrind to retain the exact same lobe specifications (lift, duration) and reduce overlap with a regrind. This is only possible when grinding from a billet. In other words, the camshafts are the same.
They grind the base value of the lobe and essentially enlarge the "top" of the cam. They can control overlap by either removing or adding material on the back of the cam.

The downside of removing material from the base of the lobe is you have to have your cam towers milled.

The only advantage to a billet cam is not having to mill your cam towers. Otherwise, no difference.
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Post by SOHC 240SX »

Jordan Gladman wrote:
deviousKA wrote:
BTW, PDM lists a c404 turbo grind, that they advertise has less overlap. This is incorrect, as there is no possible way with a regrind to retain the exact same lobe specifications (lift, duration) and reduce overlap with a regrind. This is only possible when grinding from a billet. In other words, the camshafts are the same.
The downside of removing material from the base of the lobe is you have to have your cam towers milled.
The advertised specs are the same, which is junk info. If you measured the two cams at .050 thou, the specs would be different. Showing that the turbo cam would have less valve overlap.

The advantage of solid adjustable rocker arms is that you can use any regrind cam and do not need to mill your cam towers.
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Post by deviousKA »

Jordan, thanks, I know what regrinds/billets/and cam tower modifications are. You could say I have some experience 8)

You can grind the ramps so that you will have less lift during overlap, but the actual overlap in degrees will be the same if both profiles have the same duration using a low lift or advertised duration type measure. The lobe seperation angle on a regrind is not changed, at least not with these in question. This can only be changed when grinding from a billet.

Like others have said, only way to truly compare two profiles is to start measuring them at the same amount of lift, and use the same tool/setup for both. When you measure starting from x amount of lift, you are ignoring certain amount of duration in degrees with up to x amount of lift, which could be overlapping the other lobe/s. Its just a simple fact to be aware of.

These profiles are relatively mild, the NA cams under 280 duration work great with turbo sohc.
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Post by Joel07 »

Ok, you said advertised duration is measured at .006" and if you don't do it that way, it is wrong. By who's standards? Who decided it was correct to measure at that lift instead of another section of lift? Can you prove to me this is an accepted standard rule in the automotive industry? Can you show me that everyone follows this "set standard"? How is this standard enforced so that all dealers properly quote cam specs at this exact lift? Do big name companys like Crower, Comp Cams, and Crane cams all follow your rule or do they measure duration as soon as the dial begins to move?????
It's ASE Standard procedure to measure advertised duration at .006". And yes, all the big cam companys, and even all the small ones measure it the same way. Like I said, if they're measuring it when the indicator starts to move, they're doing it wrong.

Still not sure what you're talking about with the rocker arm deal. Of course you can't measure on the rocker arm, you measure with a dial indicator on top of the valve, like you did, or if you can find a way to set it up solidly enough, you could also measure directly off of the cam lobe while it turns, and multiply by the rocker ratio to get valve lift, just like the V8's.
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Post by Calesta »

Everyone- thanks for the comments and the extra input. I didn't think this thread would generate this kind of discussion.

devious- sorry I left out your cam. I had compiled this list long before I found your site. Someone on NissanMinis of all places even pointed out to me that I had left your cam off the list! It's added to my file now.

As for cam lobe durations, I always assumed that advertised durations were measured from the base circle. Most good cam manufacturers will list a duration at 0.050" along with the advertised duration, but not all of them do. I know that Crower lists this spec on their site. I wish there was a way to measure the "slope" of the lobe and post it up along with the duration/lift specs, but I know a bunch of cam makers want to keep that information secret. :)
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Post by Calesta »

Reading back through, I just saw the information devious posted about the 90-94.5 D21 cam. I didn't know that... and I don't have an older D21 engine to measure the specs against either. I'll try and have my 95 cam measured when it comes out.
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Post by tastyratz »

as far as the turbo cams go I asked geof the same thing when I called him. the cams retain the same amount of duration and lift specs, but what he does to decrease overlap is "widen" the lobes seperating the i/e a bit. I.E. start opening the intake a few degrees sooner and start opening the exhaust a few degrees later. I dont know if he seperates one more than the other but that is how that is achieved. essentially they are offset a bit.
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Post by SOHC 240SX »

deviousKA wrote:BTW, PDM lists a c404 turbo grind, that they advertise has less overlap. This is incorrect, as there is no possible way with a regrind to retain the exact same lobe specifications (lift, duration) and reduce overlap with a regrind. This is only possible when grinding from a billet. In other words, the camshafts are the same.
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The specs they give out to the public are general and vague. Thats why they are referred to advertisted duration, it is merely to advertise the cam and make it sell. The true specs of the 2 cams (N/A and Turbo) are different. By looking at cylinder 1's intake and exhaust lobes, you can see much separation they did from the regrind.

N/A motors are basicly air pumps. In a N/A motor, the motor has to draw in the air verses a FI motor which compress the air in. It is because of this main difference that N/A motors make more power with higher duration and high valve overlap. To draw in as much air as possible.

FI motors on the other hand, have 2 different areas of pressure. The pressure in the exhaust manifold and the pressure in the intake manifold. If valve overlap is too high in a FI motor, the pressure in the exhaust manifold will flow backward and return back to the head and even back into the intake manifold. This causes the motor to see higher combustion temps and can even cause detonation. Thats why N/A cams will not be effective for FI motors and why valve overlap must be kept as low as possible on FI motors.
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Post by JGSturbo »

It should be noted most stock cams have decent amounts of seperation... which in alot of applications makes the "turbo" one of the lesser power gainers.
Which would be why the cam would be one of the last items I would put on.
Don't get me wrong, I'm not dissing the turbo cam but theres plenty of more important areas to spend $$$ before the turbo cam.
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Post by SOHC 240SX »

I wouldn't upgrade the cam for reasons of more power, but for reasons of keeping valve overlap down as much as possible. This will allow the motor and turbocharger to work better together versus making them fight each other. When the motor and turbocharger compliment each other, higher power gains are easily obtainable. I would always use this as a premise for deciding what modifications to do to your motor and turbocharger system.

But then again, there are some people who are more interested about shiny chrome bling bling looks than effectiveness. It is important to understand that you can have both.
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Post by tastyratz »

flowing back to the intake manifold is more of an extreme case. more than likely your just gonna have wasted boost from too much overlap. your pressurizing the intake charge and just blowing it right out the exhaust instead of pressurizing the cylinders. overlap on na uses the vacuum of the exhaust flow to suck in more fresh air through the intake. doing that when you spent all that work and time pressurizing the air doesnt work so well
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Post by SOHC 240SX »

Backpressure in the exhaust manifold is not an extreme case. This is based on several different things like exhaust turbo manifold design, turbocharger size, restrictive exhaust system and for every given amount of pressure loss through the intercooler system will show up as an increase in the exhaust manifold pressure X2. So if you build or design all these areas of a turbocharge system poorly, reversion back into the intake manifold via valve overlap is totally possible...not extreme.
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Post by deviousKA »

I can see that turbo cam does have the lobes chopped down a bit, the lift is reduced. The actual overlap in degrees is the same like i mentioned above, but this would only show if you began your measuring at .005-.006". The

The stock profile even looks more aggressive in some parts of that lobe/s, but i may be wrong.

The cams we are discussing are fairly mild, NA included. I dont build turbo KA really, If i did i would have something much more aggressive than any in discussion. Single cams are cheap enough to have a rack full of grinds, only way to know is to test.
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Post by Joel07 »

Reason the lobes look smaller is because they have been ground. Hard to put metal back on em... :lol:

They reduce the base circle, which allows them to grind the lobe the way they want, to a point anyway. There's still only minimal material they can take, since they're only taking about .020 off of the base circle. Just can't get that aggressive of a cam without starting with billet cam blanks.
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Post by SOHC 240SX »

They machined the base circle fairly low. Almost to the point were there is no lip. I tried ordering a billet cam from Nissan Motorsports. The darn thing kept being put on back order for over 4 months. I couldn't wait any longer so I just send my stock cam to PDM/colt for the regrind which turn out to be fast and cheaper. I wish though I did get the billet cam and send it to Crower. I would have like to see what kind of specs they would machine out for me. Just a little worried if they would be able to index it correctly as the stock cam is already index from the factory.
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Post by deviousKA »

Joel07 wrote:Reason the lobes look smaller is because they have been ground. Hard to put metal back on em... :lol:

They reduce the base circle, which allows them to grind the lobe the way they want, to a point anyway. There's still only minimal material they can take, since they're only taking about .020 off of the base circle. Just can't get that aggressive of a cam without starting with billet cam blanks.
My reply was much more specific, I was commenting on specific areas of the profile itself. We are discussing regrinds which obviously have smaller base circles and lobes to suit. All comments are "to scale".

There is enough material to work with to get plenty aggressive on ka24e cam regrind. I have a couple race only cams at the shop, .506" lift/310 duration both intake/exhaust, regrinds.

Main limit with a regrind is the lobe seperation cannot be changed, within reason. The lobes can be ground to "simulate" extra seperation by working with one side of the lobe, reducing lift. The other side of the lobe generally stays more intact (intact as in ramp similar to an oem profile). This does not change the lobe seperation it is just a more mild profile which yeilds less lift during overlap, the overlap in degrees is the same depending on where you start measuring. These comments regarding c404 vs c404t cams, other profiles would not have the same overlap in degrees.
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Post by tastyratz »

interesting devious. ive been working with geoff on the sohc cam and ill ask him about that next time I talk to him. Technically its not less overlap in degrees at the lowest ase measurement point, however it still achieves that in a more mild stance if what you say is correct. there should be some new interesting cam development for the sohc soon and I will post more on it later.
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Post by JGSturbo »

SOHC 240SX wrote:Backpressure in the exhaust manifold is not an extreme case. This is based on several different things like exhaust turbo manifold design, turbocharger size, restrictive exhaust system and for every given amount of pressure loss through the intercooler system will show up as an increase in the exhaust manifold pressure X2. So if you build or design all these areas of a turbocharge system poorly, reversion back into the intake manifold via valve overlap is totally possible...not extreme.
Reversion is going to happen with any overlap because something alot of people don't talk about is the fact that ALL (for our purposes) turbo systems have higher exhaust pressures (compared to the intake pressure). A small turbo like the Sil T25 intake to exhaust pressure ratio is around 1:4 (a guess, depends alot on engine size)...
That would mean for every psi of intake pressure there will be 4 psi inbetween the turbo and the head on the exhaust side.
THe larger/more efficent turbo you use, the lower the ratio but its damn near impossible to have 1:1 backpressure ratio because the backpressure is what drives the turbo (something has to). If you where able to put in pressure and get the same pressure out it would be 100% eff. which is impossible considering the weight of the turbine wheels, the friction of the bearings, etc.
So as you can see maintaining seperation is very important with about any turbo engine (unless your running methonal and need a little heat to get a good/full burn)... And while a long tube header will have better control on the pulses, your still cracking a valve with lots of pressurised exhaust gasses behind it... reversion will happen. A long tube header and other anti reversion tactics (like an over ported exhaust head flange) will help reduce the volume, even a little reversion can still hurt by detonating the incomming charge when you pushing higher boost levels.

But like I said stock cams don't overlap very much to start with (hey, it was the 80s they had to cut emmisions and save gas)... but more lift is always better. Something that I would like to see is a high lift / low duration cam... whether the stock valve train can take it has yet to be seen.
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Post by tastyratz »

Ok guys I talked to Geoff @ colt cams and actually emailed him a link to this thread to get the lowdown and full out information from him. We have been going back and forth since then on this and getting our information on things straight and that explains the delayed reply. What he was saying to me made a lot of sense and he seemed less than happy with the **** that was flung here. He was telling me to measure the cam he went with a 2.5 in radius pad which will produce a much true-er reading. Measuring with a dial indicator is not going to provide accurate readings for duration because it wont react like a *properly sized* pad would through the rotation due to the arc in the pad. Devious: you admitted openly to just copying someone else’s work and selling it as your own. Personally I wouldn’t have just come right out and said that, there’s a lot of legal ties to just plagiarizing someone else’s work and design. This thread is full of propaganda **** flinging competition which Is not very professional and makes you look bad to people as a business. Geoff gave me the numbers of the stock cam to post on the forum and blow things open a bit.
0
stock duration

0.001 272.5 Deg
0.002 264.1
0.003 256.5
0.004 249.9
0.006 238.1
0.010 224.8

Since his cam is already being copied it doesn’t matter posting the specs of that for people to view for them self.

C.404 sohc grind:

0.001 304.5 Deg
0.002 286.9
0.003 275.9
0.004 266.3
0.006 254.3
0.010 243.3

Note there isn’t really a true "industry standard" and especially with a hydraulic cam system if you measure @ .006 its an irrelevant place since you wont actually achieve those numbers due to slack and absorption into the drive train. Measuring @ .050 is a much more accurate and honest spot to do so. Harley engines measure around .053 and European engines tend to measure around .040. Higher numbers measured @ .006 thou are actually negative to engine performance. Doesn’t make sense to think of at first but below 6 thou its irrelevant and higher numbers will negatively impact your ramp speeds. think of it as the shorter distance will get you there faster.

As far as decreasing overlap without changing the duration and lift numbers its absolutely possible in the way you grind a cam. if you can make it bigger why can't you grind things smaller and space them out a little bit more? Depending on how far down you want to grind you can almost put those lobes wherever the hell you want really.

I also asked him about the numbers game in advertising saying a cam is a 272 for example and he completely agrees the numbers put out are b.s. Think of them more as a reference to guide you that’s what its established for. its an advertising thing. people would look at a cam and say "I don’t want a 266 cam that’s probably smaller than stock" no people would grab the 272 because it sounds bigger. the general public is just one idiot zip tied to the next by the same general thinking propaganda. This is the same reason AMD came out with the XP rating system on their processors because people would just buy the computer processor with a bigger number. If amd tried to explain workload per cycle or anything more technical most people just wouldn’t understand. so to keep with the competition its a marketing thing. This is why nobody who sells a 272 will dyno the same, because they are all different grinds. is it honest or accurate? nope not a bit it sucks he thinks so, I think so, and most people who read this probably will think so. However its a business world and you’ve got to be able to market your product to the general public even if it mainly consists of people with the IQ equivalent of a ball point pen.

and directly quoted by Geoff in addition:
"240's are running 2 int valves. So should duration be doubled? or would an advertised duration that people are comfortable with for an rpm power range be better! I would think the latter one and that is what I tend to go with. Another good point to mentions on solid lifter cams, if you take your advertised duration @.006 and you are running
an average of .010" - .020" or so for clearances. Then 006 is irrelevant."

P.S. updated numbers
Originally valve lift is a little lower.
He was using 1.52/1 as the ratio, but recently discovered it is 1.5/1
Not a big deal but it is more accurate.

STOCK
INT: 186° @ .050 / ADV. 240° .409 Lift
EX: 193° @ .050 / ADV. 248° 409 Lift

C.404.H
INT: 204° @ .050 / ADV. 268° .435 Lift
EX: 210° @ .050 / ADV 272° 435 Lift

any questions ladies?
SOHC 240SX
Dont Question My Nissan Knowledge
Posts: 514
Joined: Fri Oct 22, 2004 5:53 pm
Location: Austin, TX
Contact:

Post by SOHC 240SX »

First of all I am not a lady.

Second, I am not going to take your word that those numbers represent the C404 turbo specs. I asked for a spec card from Colt and was denied. Any REAL cam shop always supplies specs with the product sold. Hell, I didn't even get any install instructions or break in instructions (not that I need them anyways), but to me that seems less than acceptable for a Professional Company. I am not saying their quality is poor, in fact its the best I have seen around, but to only send the stock cam back without a spec card, paper work, or sometype of serial number is poor in my opinion.

I agree that the dial measurement is not accurate, I stated that from the beginning. But all I was provided with was advertised duration specs, which you admit is junk, nothing more solid. So a dial was used as a starting point to at least get a ball-park figure of were to start from.

Third, all my posts are factual and true to the best of my research and findings. I do not nor ever fling any kind of crap on this thread. If you want to knock someone out, address them specificly, but don't group me to the pile because someone said something that was incorrect.

Finally, you said the 1.52 or 1.50 to 1 is the ratio....ratio to what? If your talking about the rocker arm ratio, then you missed my previous thread where I stated the rocker arm ratio to be 1.422 to 1. That information was from Nissan Motorsports directly. If you think that is wrong, just prove it and I'll accept it. Seeing how Nissan Motorsports own joo, I'll believe them over you until you have undeniable proof they got it wrong.

The only thing I agree with you is that there is not SET STANDARD to measuring cam duration. Everyone does it differently with different equipement. If everyone begins to do it the same way, like measuring at 50 thousandths, then a common standard can be set. Its like measuring horsepower. That is a set standard everyone follows,

Until you can prove anything you just said above, it looks like your the throwing around false information. Talk about looking like an idoit. :roll:
Last edited by SOHC 240SX on Fri Sep 16, 2005 4:44 pm, edited 1 time in total.
-los
deviousKA
240sx Wannabe
Posts: 157
Joined: Sat Jul 30, 2005 11:23 pm
Location: Idaho

Post by deviousKA »

tastyratz, jfyi the cams that I sell are completely legal and not just copied without consent. My grinder is in constant contact with Colt Cams for various reasons, just over the border here in the states. In fact, the cams are ground on machines (some) that were purchased directly from Geoff himself a couple years ago. That should ring a bell to anyone that should know anything about the situation, and out reading a internet message board for whatever reason.

So you might want think twice before jumping to slander someone about something that has nothing to do with yourself. Look bad to people as a business? Are you serious? You know nothing about my business or me personally so take a hike MR. PEDOPHILE AVATAR.
deviousKA
240sx Wannabe
Posts: 157
Joined: Sat Jul 30, 2005 11:23 pm
Location: Idaho

Post by deviousKA »

Oh and BTW, just to add.

"This thread is full of propaganda **** flinging competition which Is not very professional and makes you look bad to people as a business"

Calesta put together a comprehensive sohc camshaft list, and wanted to include all cams available for the ka24e. The only reason I ever posted was to help share information. I answered questions that were asked. I dont post around trying to sell parts. If you actually knew much about KA, in general you would know that.

If anyone was to have a problem with this (besides yourself obviously) I could be contacted or my posts deleted, easy as that.
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