Ive read that a cam acts different in different size engines ie, a 224 duration at .050 .500 lift will seem/act like a bigger cam in a 350 vs seeming/acting like more of a mild cam in a 455 or stock in a 502. Im wondering if this is true? Im thinking of doing a cam and intake on one of my 215's and im also looking at cams for my 455 so I have those type of specs in mind. I dont want to put a cam in it that is small for a 455 but will act big in the 215, its in front of an auto will stock stall. I have a 212 duration .490 lift cam in my 181ci 4 cylinder nova but idk if it idles/sounds built because the cam is big for the cid or because its not running perfect.
Frrom a Mike Drew post: The following are LCA's that are commonly associated with high performance engines in regards to carbureted SBC CID. These are only guidelines and should not be a primary bases for cam selection. They get me "in the ballpark" only and should be used with discretion. 112-114 302 110-112 327 108-110 350 106-108 383 104-106 406 102-104 420 The following are duration at .050" numbers that I have been using when looking for grinds. They are for 350 CID. When building larger engines, I will add 5-10 for 383 CID and 10-15 for 406 CID. When building a smaller engine, I subtract 5-10 for 327 CID and 10-15 for 302 CID. These again are only my "ballpark numbers" and should be use with discretion. Have you noticed I keep saying that? 205-210 truck/RV 210-215 mild performance 215-220 high performance street 220-225 street/strip 225-230 emphasis on strip, stall converter 230-235 poor street manners, high rpm use 235+ race only
Your basic understanding is correct. You can look through the various cam mfgr catalogues and see the same pattern. If you look at the oem cam specs for the 455 and compare to the 350 (Buick, Pontiac or Olds?) you will also see a pattern if the intended service is similar. The cam specs for the same brand 400 will likely be in between. .
Thanks, the cams im looking at are spec'd for 300-340 buicks, though im working on an olds 215. I just want some street performance without going to big for a stock stall. The cam in particular has 210 duration int 218 exh
A smaller engine usually wants a smaller cam, so it will not loose too much low end torque...which it doesn't have as much of just because it has less displacement. With more cubes, you can "afford" to lose some bottom end, so a bigger cam will work fine.
For comparison, I sell a lot of cams for the 241 Dodge Hemi and your 210/218 is about as big as I would ever normally recommend. I think that in a 215 it might be a tad bit big. I would probably look at something closer to the 195-200 mark if all else is stock. .
I was figuring that would be about the biggest I could go without being to big. It is stock now but if I do a cam ill go with an edelbrock performer and may pull the heads and do some bowl work. It is rated as 10.25:1 comp.
I reread the OP and noticed a reference to a 4cyl 182. The recommendations you get are generally made for V8's. A 182 4 is equal to a 364 V8. For your 215 there is a large market for the Rover performance parts. Just google Rover aluminum V8. The 210-218 should be ok, it might help to advance the cam 2 - 4 degrees to help low end.
I was using my 181ci nova as an example, It has a 212 duration at .050 .490 lift single pattern. Idk if being a four cylinder makes it a little different but if not I think that the 210/218 cam in the 215 would be just fine.
To the camshaft it's CID per cylinder; 181/4= 45.25 215/8 = 26.875 But the can should be ok, as I said you may want to advance it 2 - 4 degrees to help the bottom end.
The cam in my 215 is a KENNE BELL C-114A hydraulic flat camshaft. The C-114-A number is stamped on the rear of the cam. Advertized in KENNE BELL'S BUICK 1984 catalog as the first cam that obtained 100 mph in the 1/4 mile in his Buick 300. The Applications are; BUICK 215, 300, 340, OLDSMOBILE 215, Rover all 3.5, 3.9, 4.2, or any 4.0, 4.6 V8 using a DISTRIBUTOR. The 114 degree lobe separation angle makes this cam good for moderate street performance with good torque with a wide power band. It has been discontinued for 27 years. The specs are: LIFT ( with stock 1.6 rocker arm ratio).. INTAKE (I) .488. EXHAUST (E) .494. DURATION.. (I) 284 (E) 294.... DURATION AT .050, (I) 218...(E) 228...CAM LIFT...(I) .304 (E). .309. INSTALLED INTAKE CENTER LINE (I) 109. LASH 0. LOBE SEPERATION ANGLE 114.
anyone know what the early 60's isky e-2 cam specs are for the 215? I found an old article where they made good power with one.
These numbers are R/S ratio related not CI, they are generally too wide, especially at the small ci end of the scale, and theres WAAAAY more to it than that. For instance, 283 chevy SS motors run LCA's in the area of 102-104. As general rules, the "right" LCA will narrow as the duration goes up, R/S ratio goes down, engine becomes more intake port restricted relative to bore size, or mech. compression ratio goes down. Also, if the combination is octane limited, which almost all HAMB motors are, the intake closing point (Which is governed by LCA+duration)is pretty much dictated by the mech. compression ratio that you are going to run. This info is worse than vague and oversimplified, its downright misleading.
Generally speaking the bigger the cubic inches the cam will act tamer. Example: When I built my first 502 I put in a cam that was quite nasty in a 396. The engine ran almost as mild as a stocker. Called Comp Cams and their recommendation was light years wilder. Frank
will be running 455 olds with manual trans 215 2bbl 3 on the tree 215 4bbl auto floor shift the wagon is the one i want to put a cam in
The relationship is really on stroke, just so happens larger CID engines usually have longer strokes. The piston tends to dwell at TDC and BDC for longer times on engines with longer strokes so you can have more cam overlap and reversion becomes less apparent. If you were to plot a sign wave of the cam vs the pistons speed you would see engines with longer strokes would have less piston speed during the over lap and thus less reversion. So engine with longer stroke are less cam sensitive or can tolerate more cam timing.
Well, you know, I still think it is, in spite of the of the huge volume of complete BS that seems to gain credibility just by being out in print on some website. At the same time as crap like the above gets spread around, theres also tons of really worthwhile stuff. But the trick is, like you said on the thread about the hemi book, you have to look at it and think carefully about what is being said, and learn to discriminate. Like I said on that cam thread with the bs about "overlap bleeding off compression" the more you learn about the basic fundamental physics and geometry of how the 4 stroke engine actually works, like understanding the four strokes, and the relationship of the crank/valve motion through those events, and understanding how changes to rod/stroke ratio change the motion/accelleration of the piston through the stroke, the more you can at least start to weed out the complete bs. Asking people to hand you fish is a waste of time, the best thing to do is learn how to fish.
Two critical questions to be answered before anyone even starts thinking about a cam recommendation for this deal, unless they are pretty much just pulling numbers out of thier ass . What casting number are your heads? According to what I have read, theres three different head castings for these motors, all with different sized chambers, #829 at 43 cc nom, #534 at 38cc nom, and #746 at 51cc nom. This is going to govern LCA... next IMPORTANT question here, are you actually building a motor, or looking for a cam to bolt into a stock, running engine? FWIW, if my memory serves, there was a guy named Phil Baker in the Seattle area that used to build a lot of these motors. Whether he is still around or not, I dont know.
ok, what heads are on it? Theres a difference of two full points of compression (8.3/1, 9.4/1 and 10.3/1) across the three heads. Is it a factory 4bbl motor? I assume you are keeping the original trans and 3.07 rear?
Its a factory 4bbl, I dont know what heads are on it. yes stock trans, stock rear but I dont know what gears.
One more thing, the reason i asked if this was a bolt-it-in deal, or if the OP was building the engine? If he were building an engine, I would have suggested getting a set of the 43cc chamber #829 heads, and cutting .020 off the decks, so he could build a 10/1 motor with tighter squish. This would have been the ideal situation.
You will like having a 455. Here's a nice example of a cam, compression, & gear upgrade. I'm building a w-30 spec 455 right now with the factory cam https://www.youtube.com/watch?v=10i1y2ZFFT4 Here's my w-30 motivation https://www.youtube.com/watch?v=qzBOsbcvOxk On your 455, it will take up to 230* @ 050 & .500 lift max. Beyond that, you will need to plan for aftermarket adjustable rockers. Here's a nice sounder https://www.youtube.com/watch?v=mfC0icZ-FQs
Well written , because I run chevy 302 , in ot car and I wouldn't want to run a 114 lca in it, I would have to wait till next week to make any power ! Lca depends on how tight you want to rev your engine ,cruiser needs lower rpm drivability ( 114-116 Lca) performance street ( 110-112 Lca) and high performance ( 102-108 ) just a suggestion !
FG, I think applying empirical 4 inch bore SBC knowledge to a 3.5 bore engine with a spark plug located almost dead center of the bore may be skewing the results. We have a smaller bore, shallow chamber, and great plug location. I believe it's going to be very knock resistant. Thoughts?
In order for the DCR to mean much you have to charge the cylinder. I think the tiny ports flowing 130 cfm will throttle the intake charge enough to make it work at 8.11 or higher. Of course instead of guessing we can draw on a wealth of Rover enthusiast experience. just my 2c
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