Cam selection for 340 stroker

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xring

xring

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From what I have read and heard, the stroker engines can use more camshaft duration than the stock-stroke engines. The one book I have says for a given camshaft duration in a stock-stroke engine, the stroker engine will have similar idle and power characterstics with about 6* more duration. In other words, the same cam in a stroker will appear to be more mild than it would be in a stock-stroke engine.

Should the manufacturers camshaft application charts be skewed to lower RPM's for use in strokers?

What is the "biggest" cam I can get away with using a 3000 rpm stall converter in my 340/416? (Assuming the rest of the build is made to match...compression ratio, intake/carb, gears, etc)

Thanks!
 
Are You Wanting A Hyd. Or Solid Or A Poller??
 
Oops. Should have said, mechanical flat tappet cam.

As mentioned in another post, Comp recommends the XS282S.

Intended car use is weekend cruiser/occasional drag strip.

Thanks.
 
call cam-motion tell them evry thing about your motor and what you want to do and thay will fix you right up.that way there is no gessing and spending alot of money tring things.thay have always done good for me.
 
The 282s isn't a bad cam. It idles pretty raspy in a 340, a 408/416 will make it idle like a 262H.
 
Cams around 250°@.050 will still have a street idle quality. If you use that as a guide, you can pick a cam regardless of the engine size they have in the catalogs.
 
crackedback said:
The 282s isn't a bad cam. It idles pretty raspy in a 340, a 408/416 will make it idle like a 262H.
Click to expand...

But will that hold true for the RPM range of the cam as well, or just the idle quality?
 
It won't rev to the top of the range that comp says it will, not in a 408.

Strokers eat up cam duration pretty easy. A 250* cam in a 340 will run to a higher rpm range than the same cam in a bigger inch engine, so yes, the top end range number will be reduced as well.
 
crackedback said:
It won't rev to the top of the range that comp says it will, not in a 408.

Strokers eat up cam duration pretty easy. A 250* cam in a 340 will run to a higher rpm range than the same cam in a bigger inch engine, so yes, the top end range number will be reduced as well.
Click to expand...

I'm learning things here. Now, what about the bottom end? Will a cam that specs at, say, 3500-7000 in a 340 be more like 3000-6500 in a stroker?

Thanks!
 
Xring,
had you considered the comp 'extreme high lift' series the XE285HL has given me the best numbers of any cam I put into the computer. I will be using it on a 416 stroker and pump gas. It is also just a little bit bigger than the 282 but the curves are more to my liking. It reads 586Hp @ 6500 and 547 ftlbs @ 5000. On a desktop dyno program, which we all know is just an estimate.
As for the bottom end with RHOADS lifters it reads 216Hp/453ftlbs @ 2500, I dont know if thats enough bottom end for you :-D
Andrew
 
I'll check out the XE285HL. I've just been using Comp's CamQuest software and seeing what it recommends. I'm just trying to get an understanding of how the cams that are spec'ed for a standard-stroke small block will behave in a stroker.

Without actually just buying a cam and putting it in there, that is!

Thanks
 
Not exactly an apples:apples comparison, but close. I have a 360/408 stroker, Edel heads, 9.6:1 static compression, M1 intake, 1 5/8 hookers into 3" exhaust, with a 4000 stall 9.5" dynamic converter into 727 with 3.73 gears.

I am runnig a Comp Hydraulic Roller for a factory roller engine that has the following specs: 236/242 in/ex @ 0.050", .544/.541 lift. I have a best time of 12.26 @ 109 mph. I get cylinder pressures of aroun 175 psi on a cold check. Idles at 900 with 12" vacuum.

I should have gone much bigger in duration, and am trying to figure what to do now. Car runs great, plenty of bottom end torque, but not so much up high. The idle is lopey, but completely drivable. Best times come when i shift at 5300 rpm!

Hope this helps.
 
That does help.

I've got to decide how radical I want to go...the engine will eventually be in a car that will be a weekend cruiser...so it doesn't have to be very practical.

If I had the budget I'd go for a mechanical roller...it looks like it would make more peak power than the mechanical flat tappet cam and still not require a any more than a 3000 rpm converter.
 
I have the following cam, NEW in the box with NEW lifters.


http://www.jegs.com/i/Mopar+Performance/312/P4120233/10002/-1

If you send me your e-mail address I would be happy to send photos for your review.

I would like to see a member as yourself on here end up with it and saver them some money as well.

The shipping cost would be $120 plus $15 for insurance and packaging to protect it from damage (Hope That Is OK?)

If you would like to buy it you can paypal the $135 to [email protected] or mail me a certified bank check to my home address.

KP
 
I run this in mine at it idles but is barely a street ride by many standards. Again a lot of other stuff in it but here is what I run and crane went bye bye so I think the above post comp cams 282 is the way to go, more on a stroker for sure is OK!

Part Number: 690911 Grind Number: F-248/3602-2-8
Engine Identification:
Start Yr. End Yr. Make Cyl Description
1964 Up PLYMOUTH-DODGE-CHRYSLER 8 ROUGH IDLE, PERFORMANCE USAGE, GOOD MID-RANGE HP, LIMITED OVAL TRACK, BRACKET RACING, AUTO TRANS W/2000+ CONVERTER, 10.5 TO 12.0 COMPRESSION RATIO ADVISED. BASIC RPM 3500-7000
Engine Size Configuration
273-360 C.I. V

Valve Setting: Intake .026 Exhaust .026 HOT

Lift: Intake @Cam 3602 @Valve 540 All Lifts are based
on zero lash and theoretical rocker arm ratios.
Exhaust @ Cam 3735 @Valve 560
Rocker Arm Ratio 1.5

Cam Timing: TAPPET @.020
Lift: Opens Closes ADV Duration
Intake 38 BTDC 66 ABDC 284 °
Exhaust 79 BBDC 35 ATDC 294 °
 
I'm not sure I get what you're asking... If you need a cam for your package, give the rest of the info.. Car, gearing, use, etc. The extra stroke is about 20%. so a very basic plan is to figure it will be 20% lower rpm for similar power. So a cam that peaks at 6K in a 340 will peak at 4800. Very simplified, b ut it's close.
 
crackedback said:
It won't rev to the top of the range that comp says it will, not in a 408.

Strokers eat up cam duration pretty easy. A 250* cam in a 340 will run to a higher rpm range than the same cam in a bigger inch engine, so yes, the top end range number will be reduced as well.
Click to expand...

moper said:
I'm not sure I get what you're asking... If you need a cam for your package, give the rest of the info.. Car, gearing, use, etc. The extra stroke is about 20%. so a very basic plan is to figure it will be 20% lower rpm for similar power. So a cam that peaks at 6K in a 340 will peak at 4800. Very simplified, b ut it's close.
Click to expand...

I'm building the engine first, the car will come later...in part, the rest of the setup will depend on what I build now. But this info is what I was looking for.

Thanks!
 
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