Oval Track cam selection

-
T

threeforty

New Member
Joined
Sep 11, 2010
Messages
3
Reaction score
0
Location
North Pole
Hi, what is a good 3/8 mile oval track mechanical flat tappet cam? A power band of 2500-7000. I'am building a street stock duster with a 340.My current build is:

340 replacement block
forged steel 273 crank
eagle SIR I beam con. rods
.030 KB 10.5:1 hypereutectic pistons
indy/rhs LA-X heads 62cc 2.02 / 1.62 (gonna switch to beehive springs with titanium retainers)
1 7/8 TTI headers
chromoly pushrods
ductile iron adjustable shaft based 273 rocker arms
ported rpm performer air gap intake
750 chuck nuytten carb
canton oval track oil pan
melling high volume oil pump
windage tray
4 speed transmission

Iam looking for the correct mechanical flat tappet cam for the said power band and short track.Any help aiming me in the right direction is appreciated.

Thanks,
isaac




http://en.wikipedia.org/wiki/Hypereutectic_piston
 
40418

Cam Style Mechanical flat tappet
Basic Operating RPM Range 4,200-7,500
Intake Duration at 050 inch Lift 256
Exhaust Duration at 050 inch Lift 268
Duration at 050 inch Lift 256 int./268 exh.
Advertised Intake Duration 292
Advertised Exhaust Duration 302
Advertised Duration 292 int./302 exh.
Intake Valve Lift with Factory Rocker Arm Ratio 0.550 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio 0.571 in.
Valve Lift with Factory Rocker Arm Ratio 0.550 int./0.571 exh. lift
Lobe Separation (degrees) 106
Intake Valve Lash 0.024 in.
Exhaust Valve Lash 0.026 in.
Computer-Controlled Compatible No
Grind Number SPI2-292-302


40418 N/A 290/302 256/268 .550"/.571" 106/102 .024"/.026" 70937 73949 75702LUN
77002 73949K1LUN 93003LUN/ N/A N/A 4200-7500 Solid; Rough idle. Good cam for all out bracket racing in a heavy car. Needs
93010LUN 4500-5000 RPM stall converter or 4 speed transmission, headers, 11:1
compression ratio and 4.56 gearing or better.
 
I had this cam in my ss with your exact same combo except with 58cc edelbrock heads and a 750 quick fuel it made 488hp @6800rpm and 449ftlbs @5600 It pulled well up to around 7400.
 
Circle track engine, that cam is designed for peak power, not a broad power band. Look at the CL, timing, etc...........

Even the info says it......

Really, the mech ISKY 310/310 was a great sportsman cam, if they still make it. built a couple 360's than ran real hard at the track. BRB.
 
Ergh...

Mopar Perf used to have circle track cams, they acted suprisingly different than the other cams that looked like the same. Issue with a track engine, is you HAVE to have the broad power band, a spin out, a slick track, it's better to have the low end than shifting down.

That said, if it was me, I for one would run a cam with the same duration on both sides, while a little bit of top end on the RPM range is lost, you probably aren't up there anyway, and the same/same cams will have a more mid range snap. On the DYNO, it doesn't matter, but on the track, the object is to have the most responsive, snappy engine with the least throttle pressure. If that makes sense.

It is also a catastrohe on a circle track to go to big, while too little isn't a big deal.

Just M-O though.
 
Racer Brown ST21 call Jim Dowell his # is around here some were
I agree with dodgetkboy78, I run a 1/4 mile Dirt with a small 238@ .050 solid wth a nice flat torqe curve works great, its an old MP grind.
 
We road race a 427 inch small block Mopar with a 236 at 050 roller cam. The engine has a big fat torque curve and pulls hard down the straight. Car is a 1968 Valiant and it hits about 150 mph at the end of the straight.

Cam choice depends on gears, car weight, etc. but if it was me I'd start small and work up from there. Comp Cams has a big selection of oval track cams in their catalog for the SB Mopar engine.
 
do u have to run a 340?why not a 360!we ran a 340 for a year but it dont have the TQ that a 360 does.If u want a good cam for tq and hp call Dave at Hughes engines 309-745-9558.The last 3 years we ran 54 races and won 32 races and won the championship all three years running a 360.
 
ya i like to run 340s.i may have considered using a 360 for budget concerns but i already had the little 340. iam here asking for a little advice since my engine builder (my dad) passed away about a year ago. We used to run a 12.25:1 roller cammed W2 340 in our modified car. turned the motor 8000.We came up to alaska from texas,showed up at the track one summer and stomped everyone with our little bullet lol.Even though it isnt a power track you could still tell who had it. I can't really afford all of the exotic stuff anymore to run how i want to run in my modified.the W2s are on the shelf for now.Since my fathers passing ive chose to step down into a more budget friendly class and wanted some advice from you folks here at A-bodies.If not anything else, shoot the **** with some chrysler guys. If your not running a chevrolet up here your not in with these guys.. especially when you show up out of nowhere with a chrysler and wax everyone... repeatadly.
 
Settled on

Solid Flat Tappet

* Advertised Duration (Int/Exh): 280/288
* Duration @ .050 (Int/Exh): 251/259
* Gross Valve Lift (Int/Exh): .566"/.586"
* LSA/ICL: 110/106
* Valve Lash (Int/Exh): .016"/.016"
* RPM Range: 2800-7000

Part Number: 60442

thanks for the replys =)
 
You must log in or register to reply here.
-

Back
Top