Evo 8 cams?

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I think this may help...Brian Crower Cams sells the 4G63 Cams and i noticed in a magazine that they are both the same exact application for the Evo and GVR-4 (so no difference there)...so i would say that i am 99% sure they will fit and work (stock evo cams in a GVR-4)...but good luck with the install and let me know how it goes...btw - i have evo cams n gears for sale...

On his website the evo cams have diff. part numbers then the DSM ones. The lift profile is on the wrong side, so they are diff. The evo cams would spin backwards in a dsm so the ramp up is way more aggresive going up rather then coming down. Just for you that care. But im sure they work, I just know it will be hard on your drivetrain.

 

[85tr]

actually doing it tonight didnt get around to it last week ill let you all know if i bend all my valves ha

 

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On his website the evo cams have diff. part numbers then the DSM ones. The lift profile is on the wrong side, so they are diff. The evo cams would spin backwards in a dsm so the ramp up is way more aggresive going up rather then coming down. Just for you that care. But im sure they work, I just know it will be hard on your drivetrain.



That may be true if you swap the intake and exhaust cam, but if you cut a new slot in the end of the EVO intake cam then you're still using them in their original orientation.

 

[punisher]

Would it be possible to clock a hall effect cam angle sensor by turning the rotor 90 degrees?

I've been emailing everyone I could find on dsm boards that claim to have done it about what they did, but my searches have come up empty. I kinda get the feeling that we are missing a simple solution somewhere.

 

[85tr]

so does that mean its gonna bust up my lifters or will i be fine and what would ramping up faster than down gonnna do for power ?

 

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On his website the evo cams have diff. part numbers then the DSM ones. The lift profile is on the wrong side, so they are diff. The evo cams would spin backwards in a dsm so the ramp up is way more aggresive going up rather then coming down. Just for you that care. But im sure they work, I just know it will be hard on your drivetrain.



That may be true if you swap the intake and exhaust cam, but if you cut a new slot in the end of the EVO intake cam then you're still using them in their original orientation.

You have to be really good with a cut off wheel, because it has to be perfect or your spark will fire a millisec, or two off and how are you going to start troubleshooting that. You also wouldn't know where your timing is. Cut away if you wish, but im just saying they are not for me.

 

I found this info from 4g61t forum and it said that 4G67 has most aggressive cam from 4g63 cam

4g67 camshafts (G) are
intake - 260
exhoust - 264

4g61 camsafts are:
(D) marked camshaft:
intake -252
exhoust 251

(E) marked camshaft:
intake - 244
exhoust - 240


4g67 (G) marked camshaft:
inteke - 35.79
exhoust - 35.49

4g61 engine:
(D) marked camshaft:
intake - 35.49
exhoust - 35.49

(E) marked camshaft:
intake - 35.20
exhoust - 34.91


4g63

camshaft identification mark...(A).......(C)........(D)........(G)

intake valve open BTDC.........26.........23.........21.........18
............close ABDC.........46.........57.........51.........62

exhoust valve open BBDC........55.........57......... - .........63
..............close ATDC.......9..........15......... - .........21

4g67 uses only (G) marked camshafts from 4g63

cam height(mm):

camshaft identification mark....(A)..........(C).........(D).......(G)

.....................intake....35.49......35.79.....35.49....35.79
.....................exhoust.....35.20.....35.49.....35.49....35.49

how to calculate eg (G)
intake
18 + 62 + 180 = 260
63 + 21 + 180 = 264

so do you thing use the 4G67 head is better and cheap way to increase power because

1. More degree
2. small combusion chamber 47cc (4G63) vs 43cc(4G67) will increase around .4 the compression from 7.8 to 8.2


well FYI currently i'm using this setup for my engine...4G63T block + 4G67 head and cam

 

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You have to be really good with a cut off wheel, because it has to be perfect or your spark will fire a millisec, or two off and how are you going to start troubleshooting that. You also wouldn't know where your timing is. Cut away if you wish, but im just saying they are not for me.



The slot in the end of the cam does not have to be that precise (nowhere near perfect) as long as it is centered on the end of the cam. The timing is adjusted by loosening the CAS and turning it to either advance or retard the timing. So if the slot is off by say 3 degrees, you would simply have to adjust the CAS another 3 degrees to compensate for it. You would set the timing exactly the same as always, whats to troubleshoot? You'll still know exactly where your timing is.

I understand if you say these cams are not for you, they wouldn't be the best choice for very many people. But I have to say, a lot of people in this thread are really making an effort to say that using them is horribly difficult or will destroy your motor, etc etc. This stuff isn't rocket science, its a freakin camshaft! I'm really surprised to see how many people are so hostile to an idea that is a little outside the box.

 

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I found this info from 4g61t forum and it said that 4G67 has most aggressive cam from 4g63 cam



Isn't the 4G67 a nonturbo motor? Some people would say that in theory using a cam designed for a nonturbo motor wouldn't be a very good choice, but in practice it may actually work quite well depending on the rest of your setup. I remember reading the same info at the 4G61T board about using the different heads and cams and considered doing it on my old car. I understand some people have had positive results with it (I guess you're one of them). Although my new motor has 9:1 pistons so I wouldn't need a smaller combustion chamber. The EVO cams interest me because my motor is going to have several similarities to the EVO motor (similar compression, turbo, etc) so I figure they would be a decent match with the rest of my setup.

 

[Rausch]

the only concerns i can see thus far is:

first, the cas slot. it would obvoiuslt have to be re-done as close to the 1g cam as possible, granted ther is plenty of movement with the cas, but the closer the better.

and second, Ramp angle. as BOOSTIN pointed out, the ramp angle is not going to be the same for both sides of the cam. while this may not be dramatic, it will cause the valve train (especially if stock) to endure alot more stress. by that logic, if you have the $$ to upgrade the valvetrain, a set of higher profile cams is not that expensive when you consider all the options...

other than those two things, it should work fine.

 

i'm using the 4G67 head + cam currently and it does improve my top end but my low end a bit drop...maybe because still using cyclone mani...so far it i love it and it still cheap upgrade for me usd50 only for the head..(after 8 0f old 4g63 valve going bad - tensioner leak + noise lifter).

 

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You have to be really good with a cut off wheel, because it has to be perfect or your spark will fire a millisec, or two off and how are you going to start troubleshooting that. You also wouldn't know where your timing is. Cut away if you wish, but im just saying they are not for me.



The slot in the end of the cam does not have to be that precise (nowhere near perfect) as long as it is centered on the end of the cam. The timing is adjusted by loosening the CAS and turning it to either advance or retard the timing. So if the slot is off by say 3 degrees, you would simply have to adjust the CAS another 3 degrees to compensate for it. You would set the timing exactly the same as always, whats to troubleshoot? You'll still know exactly where your timing is.

I understand if you say these cams are not for you, they wouldn't be the best choice for very many people. But I have to say, a lot of people in this thread are really making an effort to say that using them is horribly difficult or will destroy your motor, etc etc. This stuff isn't rocket science, its a freakin camshaft! I'm really surprised to see how many people are so hostile to an idea that is a little outside the box.

If the slot is not perfect, how do you know where TDC is??? You don't, the slot is cut in refrence to the peak of the lobe so it is perfect to the cam. I agree you can cut a slot, but you would never know exactly where the cas see's TDC.

 

That is completely wrong. It doesn't matter where the slot is, as long as the rotor on the CAS is pointing at the alignment mark when the #1 piston is at TDC. And because the CAS is made to be adjusted back and forth there is no absolutely set spot where the slot must be when at TDC. The timing has to be adjusted using a timing light and rotating the CAS no matter where the slot is and that compensates for any difference in the slot. If the CAS had enough adjustment you could even use the slot in the EVO exhaust cam which is 90 degrees off from the stock cams. The only reason you can't do that is because the CAS just won't rotate that far. It has nothing to do with the slot being in line with the cam lobes. It is best to cut the slot as close to the original angle as possible, but that is only to ensure you still have enough adjustment range to advance or retard the timing as needed.

EDIT: Maybe this is a better way to explain it...when you install a new CAS or any new cams you first put the motor at TDC so that you know where the pistons and valves are. Then you turn the rotor of the CAS until it lines up with the mark on the body of the CAS which represents TDC. You install the CAS on the camshaft, then use a timing light to make the final adjustment to the timing. It would be exactly the same procedure in this case. Line up the motor at TDC, line up the CAS at TDC, bolt them together, make the final adjustment with your timing light.

 

[punisher]

Why do people keep bringing up the ramp angles? The Evo head geometry is the same as a 2g, so why would the ramps be so drastically different that it would cause any issues on a 1g? This arguement makes no sense to me at all since most of the valvetrain is the same between both the Evo and 1g. Even with swapping the intake and exhaust, why would one side have rediculous ramps that would cause issues on the other side?

There is no reason whatsoever to be concerned with the ramp angles.

 

[656of1000]

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There is no reason whatsoever to be concerned with the ramp angles.


From what I gather after reading 2 pages of this debate, the reason ramp angles are of any concern is because the evo 8 cams are said to rotate backwards from those of a dsm. I realize the evo 8's motor is a different orientation in the car, and the intake/ exhaust cams are swapped relative to a dsm, but does the evo 8 4g63 really spin backwards from a dsm? That's the question I don't know the answer to- any enlightenment? If they in fact rotate the same direction, we can throw ramp angle out the window. If not, than I'd personally be sceptical of the extra thrashing my stock valvetrain 'may' get. (not saying it would, but I'd still be sceptical, for long term durability sake.)


I noticed a lot of people saying 'why go to the trouble for such little gain?' For anyone with a setup requiring 272's or the like, this discussion isn't even for you. Myself, like others, am very interested in a mild, cheap upgrade for a stock/ lightly modded daily driver setup. If this mod works out like some say it will, it would be a perfect, all around upgrade for the lightly modded, dd dsm. Remember, not all dsm's are built for the 1320, some just like having a quick street car.

 

[punisher]

The Evo engine was only spun 180' and the head was mirrored (intake and exhaust on opposite sides). The engine still spins in the same direction as ours.

What we are trying to do would be similar to you swapping your intake and exaust cams. Yes the cams are different, but they are so similar in specs and profiles that the engine would run perfectly fine if you could get the cas to work.

 

I did a quick sketch of the way cams are positioned and which direction they rotate in an EVO motor, and then what the difference would be if they were swapped to a DSM. From what I can tell, if you were to switch the intake and exhaust cam (use the EVO intake in the DSM exhast position) then the cams would rotate in their original orientation. Any concern about ramp angles would be moot. This would require either some kind of CAS modification, or switching plug wires and injector clips around to make the timing work properly (bad idea in my opinion.)

If you use the EVO intake cam in the intake position in the DSM motor then the cams would rotate opposite of their original orientation. You would then cut a new slot in the intake cam to work with the DSM CAS and no other mods or swapping should be necessary.

So are the ramp angles going to be a problem in the second senario? Personally I highly doubt it. The EVO cams are stock street car cams. They may be more aggressive than DSM cams, but they are nothing like FP3x's or HKS 272's. The EVO doesn't open its valves with a gentle ramp angle then allow them to slam shut with a steep drop. That would put just as much stress on the valvetrain as having a very steep opening ramp angle. People run aftermarket cams (that I'm sure have steeper ramp angles then the EVO cams) with stock valvetrain all the time and it doesn't destroy anything. I have faith that the stock valvetrain in our cars can more then handle the angles of the EVO cams.

 

[Rausch]

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So are the ramp angles going to be a problem in the second senario? Personally I highly doubt it. The EVO cams are stock street car cams. They may be more aggressive than DSM cams, but they are nothing like FP3x's or HKS 272's. The EVO doesn't open its valves with a gentle ramp angle then allow them to slam shut with a steep drop. That would put just as much stress on the valvetrain as having a very steep opening ramp angle.

not exactly...

the angle of ramp up is definitely more crucial to longevity as well as performance, as opposed to the down slope of the cam. the ramping down is important to prevent from slamming thing shut too quickly. besides, we don't even how reversing the rotation of the cam will affect performance. in that respect, someone would have to really test it out. but i guarantee you that the health of your valvetrain will be diminished by running a cam that was designed to go the other way.

 

[jepherz]

I can understand angles affecting the designed performance, but is there really any lateral force on the valve itself? Remember it's being pushed by the roller, which is also held by the lifter, so verdict?

 

[Rausch]

^^^ you know, i didn't even take that in to consideration...scratch the brunt of the lateral force portion...the more i think about it, the more i would suggest measuring the ramp angle and comparing it to something that can be run with a stock setup....and against something that requires aftermarket springs etc...that would give you a good indication. i'll go delete that part of my other post now. i really shoud not try to get technical after work anymore... /ubbthreads/images/graemlins/grin.gif