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Is there any benefit to using the stock cam in my 1986 635CSi vs. a cam from a 745?

I'm running a Callaway turbo set-up.

Thanks fellas.

Not sure about the one from a 745i but, I've read here that some guys use the cam from the M30 3.3l on the 3.5l 'cause it has a more aggressive profile.

You're going to lose low end grunt with a more aggressive profile. I'm running a 265 in the S2.

right,
weve discussed this alot. The 3.3l cam is a 272-274. You loose ~10% torque in the mid, gain 10% hp on the top end. Id make that trade any day. The power delivery is one I like alot as the engine dosen't laydown at 4800rpm. The power delivery is more like a ///M5.

From what I know, the M106 cam is no upgrade, in any sense. It's not different enough from the stock M30 to be of any use.

RussC

[QUOTE="Monotalonawd"]Not sure about the one from a 745i but, I've read here that some guys use the cam from the M30 3.3l on the 3.5l 'cause it has a more aggressive profile. [/QUOTE]



[Edit by russc on [TIME]1132648060[/TIME]]

i will be using the b33 cam when i crack the head open for some mods towards the summer time.

Does no one make a turbo grind cam for the M30 ?

well metric mechanic made a cam for NA m30's but it turned out that it also worked very well with the FI m30's. i know bmw335ist (jason) had one before his horrible accident.

I'm running an M106 cam right now. Why?? I don't know other than when I was putting my regular M30 head back together with all new stuff this last time I had one laying around the shop (motronic one) and though I could tell no difference what so ever between it and my original euro L-Jet one or a regular US3.5L one, I used it anyway just because. I had to put the converter nut on the end of it to run it with my old L-Jet controls (for the old-school distributor drive).

I imagine a higher lift cam like a Schrick(?) would allow more air to be forced in with a turbo engine too, but I'm not sure how it would run in general. Ha sanyone done that? I've profiled my rocker arms to recieve a cam like that but do not have one to try yet. ~_~

right, his car made lots of power also.

RussC

[QUOTE="gol10dr1"]well metric mechanic made a cam for NA m30's but it turned out that it also worked very well with the FI m30's. i know bmw335ist (jason) had one before his horrible accident.[/QUOTE]

the Schricks are too much overlap for street use, but can work. If you need to pass a smog test, forget it, ovelap is way to high in a FI car. You'll burn up cats fast when under acceleration, as lot of overlap dumps unburnt fuel in the exhaust.

If you can get a low duration(~274 or less) with more lift in a Schrick, that would be good.

RussC

[QUOTE="Jesse "]I'm running an M106 cam right now. Why?? I don't know other than when I was putting my regular M30 head back together with all new stuff this last time I had one laying around the shop (motronic one) and though I could tell no difference what so ever between it and my original euro L-Jet one or a regular US3.5L one, I used it anyway just because. I had to put the converter nut on the end of it to run it with my old L-Jet controls (for the old-school distributor drive).

I imagine a higher lift cam like a Schrick(?) would allow more air to be forced in with a turbo engine too, but I'm not sure how it would run in general. Ha sanyone done that? I've profiled my rocker arms to recieve a cam like that but do not have one to try yet. ~_~ [/QUOTE]

[QUOTE="russc"]the Schricks are too much overlap for street use, but can work. If you need to pass a smog test, forget it, ovelap is way to high in a FI car. You'll burn up cats fast when under acceleration, as lot of overlap dumps unburnt fuel in the exhaust.

If you can get a low duration(~274 or less) with more lift in a Schrick, that would be good.

RussC[/QUOTE]

"FI" = "Forced Induction" or "Fuel Injected"? I have a Schrick 282 in my NA motronic engine, and it passes smog no problem with the stock chip, and the catcon is 3 or 4 years old and healthy. Is the problem in a boosted engine that the combustion is incomplete due to the boost forcing the mix out during overlap?

[QUOTE="russc"]the Schricks are too much overlap for street use, but can work. If you need to pass a smog test, forget it, ovelap is way to high in a FI car. You'll burn up cats fast when under acceleration, as lot of overlap dumps unburnt fuel in the exhaust.

If you can get a low duration(~274 or less) with more lift in a Schrick, that would be good.

RussC[/QUOTE]

[QUOTE="Velocewest"]"FI" = "Forced Induction" or "Fuel Injected"? I have a Schrick 282 in my NA motronic engine, and it passes smog no problem with the stock chip, and the catcon is 3 or 4 years old and healthy. Is the problem in a boosted engine that the combustion is incomplete due to the boost forcing the mix out during overlap?[/QUOTE]

Well,
I guess I need to be more clear. Yes, FI as in Forced, sorry. Thats usally the nomenclature here. But I see the confusion. With the smog test, it can vary by state also. CA were Im at can be a bitch to pass even w/o the high duration CAM. Other states are easier. You may be in one of them. It can help alot if you can tune the car as I do for the different configurations.

RussC

I don't have exhaust inspections - so would the schrick be beneficial at all? What kind of improvements would we see.... would they be drastic?

Just like any high duration cam, you loose low end torque, gain high end power. Economy would suck. If you run a cat, it will burn out fast with a turbo and high duration cam. The gains to me would not be drastic over a 274 cam. Say another 10%. Since no one here has ever used one, know one knows for sure. We know about the stock b34, b35, b33 and MM turbo grind.

RussC

[QUOTE="Tjn182"]I don't have exhaust inspections - so would the schrick be beneficial at all? What kind of improvements would we see.... would they be drastic?[/QUOTE]